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  • 1.
    Abdollahifakhr, Hamon
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsområde Datorstödd konstruktion.
    Sengul, Ceyhun
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsområde Datorstödd konstruktion.
    AUTOMATIC DESIGN OF WIRING PATTERN FOR CAR SEAT HEATERS2010Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This projects aims to develop design automation in product development. Design automation causes increase in producibility and decrease in product cost and manufacturing lead time.

    The study at hand is proposed to provide a new method and to introduce procedure to the design of wiring pattern for a car seat heater for Kongsberg Automotive, KA. KA is a Norwegian company and a global provider of engineering, design, and manufacture for seat comfort, driver and motion control systems, fluid assemblies, and industrial driver interface products. The method that currently is used in the company to create a wiring pattern is neither sufficient enough nor automated.

    In order to design the wiring pattern, at first procedure is handled by the designer. Secondly, car seat heater 2D layout is imported and then, the dimensions of the elements are defined as constraints. Then VBA codes are opened and the program is run. The result will be a wiring pattern in different 2D layouts. To make the design process easier, we have modeled five different layouts; wiring pattern of one element, two elements, three elements, five elements (with two back sides) and one element trapezoidal 2D layout.

    The algorithm written in VBA (Visual basic for application) creates the pattern according to the dimensions of the elements which are used as inputs to define constrained parameters. The created macros are simple to use and easy to modify, independent from the programming knowledge. The user is only responsible with parameter input and running the program. The solution gives wiring pattern for a car seat heater.

    Fulltekst (pdf)
    FULLTEXT01
  • 2.
    Afsaridis, Kimon
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsområde Datorstödd konstruktion. Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    Investigation of residual stresses generation in aluminum flywheel2009Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    Abstract [en]

    Quality of the castings is affected by several factors which the designer should take into consideration during the product development process. Although residual stress is one of those, it is often not considered in practical computations. Hence residual stresses are one of the forgotten areas in designing of machine parts. This master thesis is focused on the investigation of residual stresses in a high pressure die casted component, with the aim of extending its service life, by taking results from the study as a feedback.

    The investigation of residual stresses was done on a variety of specimens, cast aluminum flywheel, provided by Husqvarna AB. This flywheel is a component in a product of the same company.In evaluating the residual stresses in the part, two tools-simulation and physical measurement were used. Moreover, comparison with these two methods is also done at an area of interest on the flywheel. The simulation was carried out by using MAGMAhpdc-a module for high pressure die casting process, from the commercial software package MAGMAsoft; while for the physical measurements, the hole drilling method was used, a method believed to be less accurate at low stresses areas.

    The findings obtained from this study show that the results from both procedures are close, with small deviations observed, which reveals the reliability of the hole drilling method even when the stress levels are low. It is also found that the compressive residual stresses dominate in the component-a preferred phenomenon with regards to residual stress.

    Fulltekst (pdf)
    FULLTEXT01
  • 3.
    Agarwalla, Pritha
    et al.
    Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA.
    Ogunnaike, Edikan A.
    Center for Nanotechnology in Drug Delivery, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
    Ahn, Sarah
    Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
    Froehlich, Kristen A.
    Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC, USA; Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA, USA.
    Jansson, Anton
    Analytical Instrumentation Facility, North Carolina State University, Raleigh, NC, USA.
    Ligler, Frances S.
    Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA.
    Dotti, Gianpietro
    Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
    Brudno, Yevgeny
    Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
    Bioinstructive implantable scaffolds for rapid in vivo manufacture and release of CAR-T cells2022Inngår i: Nature Biotechnology, ISSN 1087-0156, E-ISSN 1546-1696, Vol. 40, nr 8, s. 1250-1258Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Despite their clinical success, chimeric antigen receptor (CAR)-T cell therapies for B cell malignancies are limited by lengthy, costly and labor-intensive ex vivo manufacturing procedures that might lead to cell products with heterogeneous composition. Here we describe an implantable Multifunctional Alginate Scaffold for T Cell Engineering and Release (MASTER) that streamlines in vivo CAR-T cell manufacturing and reduces processing time to a single day. When seeded with human peripheral blood mononuclear cells and CD19-encoding retroviral particles, MASTER provides the appropriate interface for viral vector-mediated gene transfer and, after subcutaneous implantation, mediates the release of functional CAR-T cells in mice. We further demonstrate that in vivo-generated CAR-T cells enter the bloodstream and control distal tumor growth in a mouse xenograft model of lymphoma, showing greater persistence than conventional CAR-T cells. MASTER promises to transform CAR-T cell therapy by fast-tracking manufacture and potentially reducing the complexity and resources needed for provision of this type of therapy.

  • 4.
    Ahlgren, Dennis
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    Patriksson, Daniel
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    Konstruktion av värmeelement2008Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This report aims to describing the work behind the development of a masonry heater.

    The masonry heater is developed in collaboration with the company Transient Design KB that is a product development company located in Alingsås. The company sees a possibility to cover a market segment where modern technology and design are missing.

    The report presents those methods and approaches that have been used and gives an overview to how the project has been carried out. It describes how the ideas behind the final results have produced and how they have been developed during the project's time. In the report you can also read about the final concept with its choices of construction and materials.

    The report is completed with a presentation of a final concept and a ground for possible future production.

    Fulltekst (pdf)
    FULLTEXT01
  • 5.
    Ahlqvist, Max
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    23 full factorial heat treatment experiment on Cu-Ni-Mo alloyed ADI: A literature study in HCF-VHCF properties of ADI and heat treatment experiments using a 23 full factorial design for potentially improved very high cycle fatigue strength2019Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Increasing knowledge and suggesting new heat treatment parameters for improved very high cycle fatigue (VHCF) strength of austempered ductile iron (ADI) are the main purposes of this thesis. The work was performed within Epiroc a mining and infrastructure company. They have performed internal research on VHCF properties of ADI had previously for one set of heat treatment parameters. The scientific community in contrast have extensively studied fatigue properties of ADI in the low to high cycle regime (≤108 cycles) but only scarcely in the VHCF regime (>108 cycles). Therefor the thesis is built upon the hypothesis: ‘Improvements in HCF strength should also mean improvements in VHCF strength’. Enabling utilization of published research on heat treatment effects on fatigue strength in the HCF regime (≥107 cycles).

    Finding an efficient way of exploring heat treatment parameters and their effects on the given Cu-Ni-Mo ADI alloy were a main objective. Thus, finding mechanical- and material properties characteristic for high cycle fatigue strength in the HCF regime became crucial. The potential in using these properties to develop and execute an experimental plan to evaluate heat treatments, yet minimizing the amount of fatigue testing required.

    The first step was identifying the heat treatment parameters (and parameter ranges) that showed high HCF strength, which are: Austempering temperature (Taus), austempering time (taus) and austenitization temperature (Tγ). Then finding the characteristic mechanical- and material properties for said high HCF strength material, found to be: high- ductility, unnotched impact energy and volume fraction of carbon stabilized austenite (VRA). With both heat treatment parameters, mechanical- and material properties distinctive of high HCF strength material an experimental plan was developed based on a full factorial design (23). The factorial design was chosen for its simplicity and inherent strengths, especially as both individual and interaction effects can be estimated for all factors (heat treatment parameters). Two levels (23), one high and one low, for each of the three factors (23) were determined necessary, giving a total of 8 heat treatment trials. The primary response variables of interest (evaluated properties) for each heat treatment trial were: ductility, unnotched impact energy and volume fraction of carbon stabilized austenite. Meaning usage of the following tests: Tensile testing, impact energy testing, and X-ray diffraction. Specimens for testing were extracted from austempered Y-block type III, initially cast by a commercial foundry with an Epiroc specified chemical composition. The main and interaction effects from the heat treatment parameters on the response variables were both calculated and visually determined. The experimental data was validated against literature found data for similar heat treatments. The evaluated experimental results showed good correlation with literature for the given chemical composition. Ultimately resulting in recommendations for a new heat treatment parameters for improved high cycle fatigue strength.

    Download (pdf)
    sammanfattning
  • 6.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Ascani, D.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    High entropy alloy deposition from an aqueous bath2023Konferansepaper (Fagfellevurdert)
  • 7.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Eriksson, F.
    Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, SE-581 83, Sweden.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Optimizing heat treatment for electroplated nip and NiP/SiC coatings2020Inngår i: Coatings, ISSN 2079-6412, Vol. 10, nr 12, s. 1-19, artikkel-id 1179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    NiP (P > 10 wt.%) coatings are amorphous coatings whose structure can be transformed by heat treatment into a crystalline structure and hardened by precipitation of Ni3P. In this study, NiP coatings and composite ones with SiC nanoparticles were produced by electrodeposition, and their structural transformation by heat treatment was studied using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The microhardness and the scratch and corrosion resistance of the coatings were evaluated and compared before and after different heat treatments. The results showed that in as-plated condition, the addition of SiC particles in the coatings did not modify the microstructure, microhardness, or electrochemical behavior. However, the SiC particles’ role was disclosed in combination with heat treatment. Composite coatings that were heat treated at 300◦C had higher microhardness and scratch resistance than the pure NiP one. In addition, composite coatings maintained their scratch resistance up to 400◦C, while in the case of the NiP ones, there was a reduction in scratch resistance by heating at 400◦C. It was also concluded that heating temperature has the main role in hardness and corrosion resistance of NiP and composite coatings, rather than heating time. The optimum heat-treatment protocol was found to be heating at 360◦C for 2 h, which resulted in a maximum microhardness of about 1500 HV0.02 for NiP and its composite coating without sacrificing the corrosion resistance.

  • 8.
    Ahmadkhaniha, Donya
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Eriksson, Fredrik
    Linkopings universitet, Department of Physics, Linkoping, Sweden.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. RISE Research Institute of Sweden, Borås, Sweden.
    Zanella, Caterina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Effect of SiC particle size and heat-treatment on microhardness and corrosion resistance of NiP electrodeposited coatings2018Inngår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 769, s. 1080-1087Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Electrodeposition of NiP composite coatings with nano and sub-micron sized SiC has been carried out to investigate the possibility of replacing hard chromium coatings. The composition and structure of the coatings were evaluated by energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analysis, respectively. Microhardness was measured by Vickers indentation and polarization measurements were carried out to study the corrosion behavior of the coatings. The results showed that submicron particles can be codeposited with a higher content as compared to nano sized ones. However, even if a smaller amount of the nano-sized SiC particles are incorporated in the coating, the contribution to an increasing microhardness was comparable with the submicron sized particles, which can be related to the higher density of codeposited particles. SiC particles did not change the anodic polarization behavior of NiP coatings in a 3.5% NaCl solution. Finally, the effect of heat-treatment on the coatings properties at 400 °C for 1 h was studied to investigate the contribution of particles and heat-treatment on hardness and corrosion properties. It was found that the heat-treatment doubled the microhardness and changed the anodic polarization behavior of the coatings from passive to active with respect to the as-plated conditions.

    Fulltekst (pdf)
    fulltext
  • 9.
    Ahmadkhaniha, Donya
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Huang, Y.
    University of Southampton, Southampton, UK.
    Jaskari, M.
    University of Oulu, Nivala, Finland.
    Järvenpää, A.
    University of Oulu, Nivala, Finland.
    Heydarzadeh Sohi, M.
    University of Tehran, Tehran, Iran.
    Zanella, Caterina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Karjalainen, L.P.
    University of Oulu, Oulu, Finland.
    Langdon, T.G.
    University of Southampton, Southampton, UK..
    Effect of high-pressure torsion on microstructure, mechanical properties and corrosion resistance of cast pure Mg2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    High-pressure torsion (HPT) processing was applied to cast pure Mg pieces and its effects on microstructure, hardness and tensile properties as well as corrosion resistance were evaluated. The microstructure of the processed samples was examined by electron backscatter diffraction (EBSD) and the mechanical properties were determined by microhardness and tensile tests. Corrosion resistance of the samples was studied via electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution. The results showed that HPT refined the grain size of Mg very effectively from millimeters in the cast structure to a few micrometers homogeneously through the thickness and created a basal texture on the surface. One or five turns of HPT produced no significant difference in the grain size of the processed Mg but the hardness was a maximum after one turn. The yield strength of the cast Mg was increased by seven times whereas the corrosion resistance was not affected by the HPT processing.

  • 10.
    Ahmadkhaniha, Donya
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Huang, Yi
    Materials Research Group, Department of Mechanical Engineering, University of Southampton, Southampton, United Kingdom.
    Jaskari, Matias
    Kerttu Saalasti Institute, University of Oulu, Nivala, Finland.
    Järvenpää, Antti
    Kerttu Saalasti Institute, University of Oulu, Nivala, Finland.
    Sohi, Mahmoud Heydarzadeh
    School of Metallurgy and Materials, College of Engineering, University of Tehran, Tehran, Iran.
    Zanella, Caterina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Karjalainen, L. Pentti
    Centre for Advanced Steels Research, University of Oulu, Oulu, Finland.
    Langdon, Terence G.
    Materials Research Group, Department of Mechanical Engineering, University of Southampton, Southampton, United Kingdom.
    Effect of high-pressure torsion on microstructure, mechanical properties and corrosion resistance of cast pure Mg2018Inngår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 53, nr 24, s. 16585-16597Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    High-pressure torsion (HPT) processing was applied to cast pure magnesium, and the effects of the deformation on the microstructure, hardness, tensile properties and corrosion resistance were evaluated. The microstructures of the processed samples were examined by electron backscatter diffraction, and the mechanical properties were determined by Vickers hardness and tensile testing. The corrosion resistance was studied using electrochemical impedance spectroscopy in a 3.5% NaCl solution. The results show that HPT processing effectively refines the grain size of Mg from millimeters in the cast structure to a few micrometers after processing and also creates a basal texture on the surface. It was found that one or five turns of HPT produced no significant difference in the grain size of the processed Mg and the hardness was a maximum after one turn due to recovery in some grains. Measurements showed that the yield strength of the cast Mg increased by about seven times whereas the corrosion resistance was not significantly affected by the HPT processing. 

    Fulltekst (pdf)
    Fulltext
  • 11.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Kruemmling, J.
    Department of Electrochemistry and Electroplating, Technische Universität Ilmenau, Ilmenau, Germany.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. Department of Industrial Engineering, University of Trento, Trento, Italy.
    Electrodeposition of High Entropy Alloy of Ni-Co-Cu-Mo-W from an Aqueous Bath2022Inngår i: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 169, nr 8, artikkel-id 082515Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study aimed to deposit high entropy alloy (HEA) coatings with five different elements, Ni, Co, Cu, Mo, and W, from a single aqueous bath. The influence of pH, current density, and complex agent on the composition of deposited coating was examined. It was shown that Mo and W were codeposited mainly with Ni and Co. pH had the most impact on the codeposition of reluctant elements like Mo and W, while current density had the minimum effect. The deposited coating had a metallic, dense, and nodular morphology with configurational entropy of around 1.6 R.

    Fulltekst (pdf)
    Postprint
  • 12.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Lattanzi, Lucia
    Department of Engineering, University of Ferrara, Ferrara, Italy.
    Bonora, Fabio
    Department of Engineering, University of Ferrara, Via Saragat 1, Ferrara, 44122, Italy.
    Fortini, Annalisa
    Department of Engineering, University of Ferrara, Ferrara, Italy.
    Merlin, Mattia
    Department of Engineering, University of Ferrara, Ferrara, Italy.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    The effect of co-deposition of sic sub-micron particles and heat treatment on wear behaviour of ni–p coatings2021Inngår i: Coatings, ISSN 2079-6412, Vol. 11, nr 2, s. 1-16, artikkel-id 180Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of the study is to assess the influence of SiC particles and heat treatment on the wear behaviour of Ni–P coatings when in contact with a 100Cr6 steel. Addition of reinforcing particles and heat treatment are two common methods to increase Ni–P hardness. Ball-on-disc wear tests coupled with SEM investigations were used to compare as-plated and heat-treated coatings, both pure and composite ones, and to evaluate the wear mechanisms. In the as-plated coatings, the presence of SiC particles determined higher friction coefficient and wear rate than the pure Ni–P coatings, despite the limited increase in hardness, of about 15%. The effect of SiC particles was shown in combination with heat treatment. The maximum hardness in pure Ni–P coating was achieved by heating at 400◦C for 1 h while for composite coatings heating for 2 h at 360◦C was sufficient to obtain the maximum hardness. The difference between the friction coefficient of composite and pure coatings was disclosed by heating at 300◦C for 2 h. In other cases, the coefficient of friction (COF) stabilised at similar values. The wear mechanisms involved were mainly abrasion and tribo-oxidation, with the formation of lubricant Fe oxides produced at the counterpart.

  • 13.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Moller, H.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. Department of Materials Science and Metallurgical Engineering, University of Pretoria, Pretoria, South Africa.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. Department of Industrial Engineering, University of Trento, Trento, Italy.
    Studying the Microstructural Effect of Selective Laser Melting and Electropolishing on the Performance of Maraging Steel2021Inngår i: Journal of materials engineering and performance (Print), ISSN 1059-9495, E-ISSN 1544-1024, Vol. 30, nr 9, s. 6588-6605Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Selective laser melting is one of the additive manufacturing technologies that have been known for building various and complicated shapes. Despite numerous advantages of additive manufacturing technologies, they strongly influence the microstructure and typically show a relatively high surface roughness. In this study, maraging steel was produced by selective laser melting (SLM), and its microstructure, hardness and corrosion behavior before and after heat treatment were studied and compared to traditionally manufactured ones (wrought, forged samples). In addition, the effect of electropolishing on the surface roughness was evaluated. The microstructural study was carried out by scanning electron microscopy equipped with electron backscattered diffraction in three different sections: parallel to the top surface (xy), transverse cross section (xz) and longitudinal cross section (yz). The same characterization was applied to heat-treated samples, austenitized and quenched as well as the aged ones. The results showed that selective laser melting produced a fine grain martensitic structure (in the as-printed condition) with a surface roughness (R-a) of about 10 mu m. There was no sign of preferred texture or anisotropy in the microstructure of as-print SLM materials. The SLM microstructure was similar in all 3 sections (xy, xz and yz). Despite finer microstructure, nano-hardness and corrosion behavior of SLM and conventional wrought maraging steel in heat-treated conditions were similar. Aging resulted in the maximum nano-hardness and the minimum corrosion potential values. Precipitation has the main role in both hardness and corrosion behavior. Electropolishing was optimized and reduced the surface roughness (R-a) by 65%.

  • 14.
    Ahmadkhaniha, Donya
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Pinate, Santiago
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. RISE Research Institute of Sweden, Borås.
    Zanella, Caterina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Electrodeposition of Ni high P composite coatings containing nano and submicro ceramic particles2017Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    In this study, electrodeposition of Ni-P composite coatings has been carried out to investigate the possibility of replacing hard chromium coatings. Therefore, electrodeposition of Ni-P based composite coating with different SiC particle size (50 nm, 100 nm and 500 nm) or B4C (500 nm) was performed. The coating’s composition was evaluated by energy dispersive spectroscopy (EDS), microhardness of the coatings was measured by Vickers indentor and polarization measurements were carried out to study the corrosion behavior of the coatings. The results showed that B4C particles can codeposit in higher percent respect to SiC ones. Ceramic particles increased microhardness of Ni-P coatings to 700HV0.01. The polarization behavior of all the coatings in 3.5% NaCl was similar in as plated state proving that particles did not hindered the passive behaviour. Finally, the effect of heat-treatment (at 400 ºC for 1 hour) on the coating’s properties was studied to compare the contribution of particles and heat-treatment on mechanical and corrosion properties of the coatings. Heat-treatment increased the coating’s microhardness and changed the anodic polarization behavior of the coatings respect to the as plated conditions.

  • 15.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Sieber, M.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Improving the electroplating simulation model for producing uniform coating thickness distribution2023Konferansepaper (Fagfellevurdert)
  • 16.
    Ahmadkhaniha, Donya
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Tsongas, K.
    Centre for Research and Technology–Hellas, Institute for Bio-Economy and Agri-Technology, Thessaloniki, Greece.
    Tzetzis, D.
    Centre for Research and Technology–Hellas, Institute for Bio-Economy and Agri-Technology, Thessaloniki, Greece.
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Study of the effect of pulse plating parameters on the electrodeposition of NiP and NiP/SiC coatings and their microhardness values2021Inngår i: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 99, nr 1, s. 29-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study is focused on finding optimised conditions for electrodeposition of NiP and NiP/SiC coatings, which enhance the coatings' microhardness. Both the effect of particles and the effect of heat treatment at 400°C for 1 h on the microhardness of the coating were studied. The effects of pulse electrodeposition parameters including duty cycle, frequency, and peak current density on the composition of NiP and NiP/SiC composite coatings were examined, and the results were compared with those from direct current plating. Pulse plating increased the current efficiency of NiP deposition while decreasing the phosphorus content of these coatings in comparison to direct plating, resulting in higher microhardness values. It was also shown that wt.%P in NiP coating depends not only on peak current density but also on bath charge of pulse plating. Pulse plating parameters (duty cycle and frequency) and the low incorporation of SiC particles did not affect microstructure or the microhardness of the coatings, while heat treatment was the main factor that increased microhardness.

  • 17.
    Ahmadkhaniha, Donya
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Zanella, Caterina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    The effects of additives, particles load and current density on codeposition of SiC particles in NiP nanocomposite coatings2019Inngår i: Coatings, ISSN 2079-6412, Vol. 9, nr 9, artikkel-id 554Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, electrodeposition of NiP composite coatings with the addition of SiC 100 nm was carried out on low carbon steel studying the effect of additives (sodium dodecyl sulfate, saccharin), particles load (10 or 20 g/L) and current density (1, 2 and 4 A/dm2). As a benchmark, coatings from an additive-free bath were also deposited, despite additives being essential for a good quality of the coatings. The coating's morphology and composition were evaluated by scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS). It was shown that by addition of sodium dodecyl sulfate (SDS), pure NiP coating with a higher P content was achieved, and their morphology changed to nodular. SDS also reduced the codeposited fraction of SiC particles, while saccharin increased it. SiC loading and current density had less impact respect to the additives on codeposition of SiC particles. Finally, the microhardness of NiP coatings did not increase linearly by codeposition of SiC particles. 

  • 18.
    Akhavan Attar, Ali
    et al.
    Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Alavi Nia, Ali
    Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Mazaheri, Y.
    Department of Materials Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Ghassemali, Ehsan
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Improving the fracture toughness of multi-layered commercial pure aluminum via warm accumulative roll bonding2021Inngår i: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 116, s. 3603-3617Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, the fracture toughness of the multi-layered commercial pure aluminum samples (AA1050) prepared by warm accumulative roll bonding (WARB) was investigated for the first time. Based on the ASTM E561 standard, the R-curve method was utilized to measure the plane stress fracture toughness. Compact tension (CT) samples were prepared from the sheets that were processed by different ARB cycles. Mechanical properties, microstructure, and fracture surfaces of the CT samples were studied by uniaxial tensile test, electron backscatter diffraction (EBSD), and scanning electron microscopy (SEM), respectively. By increasing the number of WARB cycles, fracture toughness increased; after five cycles, 78% enhancement was observed compared to the pre-processed state. A correlation was seen between the fracture toughness variations and ultimate tensile strength (UTS). WARB enhanced UTS up to 95%, while the grain size showed a reduction from 35 to 1.8 μm. Measured fracture toughness values were compared with the room temperature ARB outcomes, and the effective parameters were analyzed. Fractography results indicated that the presence of tiny cliffs and furrows and hollow under fatigue loading zones and shear ductile rupture in the Quasi-static tensile loading zone.

  • 19.
    Akhavan Attar, Ali
    et al.
    Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Alavi Nia, Ali
    Department of Mechanical Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Mazaheri, Yousef
    Department of Materials Engineering, Bu-Ali Sina University, Hamedan, Iran.
    Ghassemali, Ehsan
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    High Strength-Elongation Balance in Warm Accumulative Roll Bonded AA1050 Sheets2022Inngår i: Metals and Materials International, ISSN 1598-9623, E-ISSN 2005-4149, Vol. 28, s. 346-360Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several studies had been performed on accumulative roll bonding (ARB) for AA1050; however, most of them were conducted at room temperature. Here, the ARB process was performed on AA1050 plates through nine cycles at elevated temperature. An innovation introduced a new parameter (UTS×El.ε) to compare the strength-elongation balance between the present study and previous works. Also, as another parameter, the toughness was compared. Comparing these parameters with previous works showed that the considered samples in the present study performed 14 to 63% better than the other samples, so they were more industrially favorable in terms of mechanical behavior and performance. ARB process at elevated temperature may slightly lead to grain growth compared to room/cryogenic temperature, but creates a better elongation, which ultimately leads to a better balance of the strength-elongation parameter. The results showed that the effect of inter-cycle heating was found significant on microstructural evolution and mechanical behavior. Upon five cycles of the process, the grain size was decreased from 35 to 1.8 μm. The yield strength and ultimate strength increased up to 305% and 94%, respectively. Microhardness test showed that warm ARB reduces inhomogeneity factor in the thickness after 3 cycles. Fractography by SEM showed that the sample failed through shear ductile rupture and that the dimples became smaller, more elongated, and shallower onto the failure surface as the number of ARB cycles increased. In short, the warm process is preferred to the cold process to achieve better mechanical performance and toughness.

  • 20.
    Aladov, V ,A.
    et al.
    RAS, Submicron Heterostruct Microelect Res & Engn Ctr, St Petersburg, Russia.
    Belov, Ilja
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Valyukhov, V. P.
    Peter Great St Petersburg Polytech Univ, St Petersburg, Russia.
    Zakgeim, A. L.
    RAS, Submicron Heterostruct Microelect Res & Engn Ctr, St Petersburg, Russia.
    Chernyakov, A. E.
    RAS, Submicron Heterostruct Microelect Res & Engn Ctr, St Petersburg, Russia.
    A study of thermal regime in the high-power LED arrays2018Inngår i: St. Petersburg Polytechnical University Journal: Physics and Mathematics, ISSN 2405-7223, Vol. 11, nr 3, s. 39-51Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal resistance and temperature distribution for high-power AlGaInN LED chip-on-board arrays were measured by different methods and tools. The p-n junction temperature was determined through measuring a temperature-dependent forward voltage drop on the p-n junction, at a low measuring current after applying a high heating current. Furthermore, the infrared thermal imaging technique was employed to obtain the temperature map for the test object. A steady-state 3D computational model of the experimental setup was created including temperature-dependent power dissipation in the LED chips. Simulations of the heat transfer in the LED array were performed to further investigate temperature gradients observed in the measurements. Simulations revealed possible thermal deformation of the assembly as the reason for the hot spot formation. The bending of the assembly was confirmed by surface curvature measurements.

  • 21.
    Albo Zieme, Louise
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Industriell produktutveckling, produktion och design.
    Bergstedt, Pontus
    Jönköping University, Tekniska Högskolan, JTH, Industriell produktutveckling, produktion och design.
    A pre-study for functional coatings evaluated on light metals to be applied on a new HPDC Mg-alloy: Investigating tribological and thermophysical properties, as-cast and coated2021Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Magnesium with two-thirds of the density compared to aluminium and one-quarter of steel, intrigues product developers and material scientists due to the light metal’s excellent combination of strength to weight ratio as well as their capability of being produced as a High Pressure Die Cast component compared to other ferrous or light metal alloys.

     

    However, a magnesium alloy inherits some concerning drawbacks, limiting the exploitation in structural applications and mechanical design such as automotive, heavy machinery and aerospace components. The need for a magnesium alloy that could withstand a sufficient amount of wear, temperature and corrosive environment, leads towards the investigation and evaluation of a suitable, functional coating as a solution to exploit the evident advantages a magnesium alloy exhibits. A substantial amount of research is required in order to reduce an existing knowledge gap that is the ongoing development in the search for a sufficient functional coating and adherence capability to the highly reactive substrate that is a magnesium alloy.

     

    This industrial master thesis is an early stage investigation to evaluate how the currently used aluminium substrate with an electrodeposited coating relate and compares to a heat-treated electroless deposited coating through tribological and thermophysical induced stresses. These properties are tested with proven industrial standard methods resulted in a comprehensive conclusion and discussion regarding the feasibility of applying the coating onto a commercial magnesium alloy closely related to the Mg-alloy developed by Husqvarna and thereby contributing to technological advances to the highly relevant topic within product development in materials engineering.

    Fulltekst (pdf)
    A pre-study for functional coatings evaluated on light metals to be applied on a new HPDC Mg-alloy
  • 22.
    Aleni, Afshin H.
    et al.
    Department of Mechanical Engineering, Aalto University, Espoo, Finland.
    Kretzschmar, Niklas
    Department of Mechanical Engineering, Aalto University, Espoo, Finland.
    Jansson, Anton
    Department of Mechanical Engineering, Örebro University, Örebro, Sweden.
    Ituarte, Iñigo F.
    Department of Materials and Production, Aalborg University, Copenhagen, Denmark.
    St-Pierre, Luc
    Department of Mechanical Engineering, Aalto University, Espoo, Finland.
    3D printing of dense and porous TiO2 structures2020Inngår i: Ceramics International, ISSN 0272-8842, E-ISSN 1873-3956, Vol. 46, nr 10, s. 16725-16732Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Direct foam writing allows the fabrication of highly porous and hierarchical ceramic structures with high specific mechanical properties. This manufacturing technique, however, has mainly used stabilized Al2O3 foam inks. In this work, we pressent a novel foam ink based on TiO2. This ink uses polyvinyl alcohol (PVA) as a binder and a small amount of zinc as a frothing agent. We used this ink to produce cylindrical foam samples via direct foam writing. The foams had a porosity of up to 65% and a mean pore size of 180 μm, which is significantly larger than previously reported for direct foam writing with Al2O3. The foams were tested in compression and were found to have an elastic modulus of 0.5 GPa and a compressive strength of 12–18 MPa. These mechanical properties are similar to those of porous ceramics produced by conventional manufacturing routes. Therefore, this work represents a step forward by broadening the direct foam writing process to a wider range of porous ceramics.

  • 23.
    Ali, Sharafat
    et al.
    Science and Technology Division, Corning Incorporated, Corning, NY, United States.
    Bogdanoff, Toni
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Jonson, Bo
    School of Engineering, Department of Built Environment and Energy Technology, Linnæus University, Växjö, Sweden.
    Hardness, elastic modulus and refractive index of oxynitride glasses prepared from woody biofuel ashes2017Inngår i: European Journal of Glass Science and Techology. Part B. Physics and Chemistry of Glasses, ISSN 1753-3562, Vol. 58, nr 6, s. 231-236Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper reports the hardness, elastic modulus and refractive index values of the oxynitride glasses prepared from woody biofuel ashes. The glasses were prepared in nitrogen atmosphere at 1350-1500°C with addition of Ca metal as a precursor to the extra addition of this modifier. The glasses were homogenous, but appeared translucent grey to black. They contained up to 23 eq% of Ca and 5 eq% of N. The glass densities vary slightly between 2·76 to 2·92 g/cm3. The molar volume and compactness values vary between 8·01 cm3/mol to 8·31 cm3/mol and 0·446 to 0·462 respectively. Mechanical properties like hardness and reduced elastic modulus show values, up to 10 and 105 GPa, respectively. These properties are strongly correlated with the amount of N in the glass. The refractive index (1·54-1·75) increases with increasing N and Ca contents.

  • 24.
    Aliana Cervera, Gerard
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. CERN.
    Development of acomplex robot structure: Development and analysis of a cast triple traction system for the robotoperating at CERN facilities2023Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    All devices working in hazardous environments have specific requirements to reduce the intervention of human power as much as possible. The robot that this thesis is focused on is no exception to this rule. This dissertation summarized theprocess followed to achieve a theoretical design of a traction system for the CERNBot, the robot that operates at CERN facilities.

    This traction system had to be capable of achieving a speed of 10 km/h, going upstairs and make tight turns without draining completely the battery of the device. For that purpose, it was decided to include three types of traction systems such apneumatic wheel, a track system and a mecanum-wheel (an omnidirectional wheel capable of moving in any direction). This design had to include as many commercially available pieces as possible to maintain the costs contained.

    In order to comply and extend the battery lifetime as much as possible, topological optimization was applied to the non-commercial pieces, reducing the weight of thepiece by 25%.

    After achieving the weight reduction, a discussion about the best manufacturing methodology is done, comparing the manufacture using a CNC machine or casting the device, including the possible defects and costs that both models can have.

    The results show that manufacturing this piece with casting can lead to a cheaper and more complex piece.

    Fulltekst (pdf)
    fulltext
  • 25.
    Almusaed, Amjad
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Byggnadsteknik och belysningsvetenskap. Jönköping university.
    asaad, Almssad
    Karlstad university.
    The wooden skyscraper in modern and sustainable buildings2022Inngår i: Wood Industry - Past, Present and Future Outlook / [ed] Prof. Guanben Du, UK: INTECH, 2022Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Today, the world vigorously promotes energy-saving, ecological, and environmentally friendly building materials. In constructing projects, green building materials are gradually recognized by building manufacturers. The development of environmental buildings largely depends on the development of bio-based building materials. Therefore, it is very important to develop and apply green building materials. Wood's organic warmth, softness, and other benefits, including its ability to act as a natural insulator and control moisture levels, make it an ideal building material for the future. Wood is sufficiently malleable and easy to process to create ready-made building modules from it at no extra cost. Wooden buildings fit into the surrounding landscape better than others. Wood is a lightweight, high strength, beautiful appearance, good workability, is renewable, recyclable, green, and pollution-free, so wood structure buildings have good stability and seismic performance. Wooden skyscrapers use wood as the primary building material. The architects are convinced that a lower carbon dioxide emission will accompany the construction of a wooden skyscraper compared to the construction of a conventional concrete building.

  • 26.
    Almusaed, Amjad
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Byggnadsteknik och belysningsvetenskap.
    Yitmen, Ibrahim
    Jönköping University, Tekniska Högskolan, JTH, Byggnadsteknik och belysningsvetenskap.
    Almsaad, A.
    Karlstad Univ, Dept Engn & Chem Sci, S-65188 Karlstad, Sweden.
    Akiner, İ.
    Akdeniz Univ, Dept Architecture, TR-07058 Antalya, Turkey.
    Akiner, M. E.
    Akdeniz Univ, Vocat Sch Tech Sci, TR-07058 Antalya, Turkey.
    Coherent investigation on a smart kinetic wooden façade based on material passport concepts and environmental profile inquiry2021Inngår i: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, nr 14, artikkel-id 3771Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wood is one of the most fully renewable building materials, so wood instead of non-renewable materials produced from organic energy sources significantly reduces the environmental impact. Construction products can be replenished at the end of their working life and their elements and components deconstructed in a closed-loop manner to act as a material for potential construction. Materials passports (MPs) are instruments for incorporating circular economy principles (CEP) into structures. Material passports (MPs) consider all the building’s life cycle (BLC) steps to ensure that it can be reused and transformed several times. The number of reuse times and the operating life of the commodity greatly influence the environmental effects incorporated. For a new generation of buildings, the developing of an elegant kinetic wooden façade has become a necessity. It represents a multidisciplinary region with different climatic, fiscal, constructional materials, equipment, and programs, and ecology-influencing design processes and decisions. Based on an overview of the material’s environmental profile (MEP) and material passport (MP) definition in the design phase, this article attempts to establish and formulate an analytical analysis of the wood selection process used to produce a kinetic façade. The paper will analyze the importance of environmentally sustainable construction and a harmonious architectural environment to reduce harmful human intervention on the environment. It will examine the use of wooden panels on buildings’ façades as one solution to building impact on the environment. It will show the features of the formation of the wooden exterior of the building. It will also examine modern architecture that enters into a dialogue with the environment, giving unique flexibility to adapt a building. The study finds that new buildings can be easily created today. The concept of building materials passport and the environmental selection of the kinetic wooden façade can be incorporated into the building design process. This will improve the economic and environmental impact of the building on human life.

  • 27.
    Alonso, Patricia
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Effect of graphite morphology on the thermo-physical properties in cast iron2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Cast iron is one of the most used materials in the industry due to its wide properties. Specifically, graphitic cast iron is used in applications where the material is submitted to high temperatures due to its high conductivity and thermal shock resistance. Depending on the graphite morphology, thermal conductivity or mechanical properties can be controlled in graphite cast iron. Spheroidal morphology (SGI) promotes good mechanical properties, while lamellar morphology (LGI) improves thermal conductivity. Graphite can also appear in an intermediate shape, called vermicular (CGI) that presents medium mechanical and thermos-physical properties. Nevertheless, how these properties change when the graphite change from SGI to LGI is still not completely known. 

    The present work pretends to clarify the relation between thermo-physical properties and the graphite morphology in cast iron, from SGI to LGI. This work uses solidification experiments to control the chemical composition of the alloy, more specifically, the Mg content. At higher content of Mg, the graphite nucleates and grows in nodular shape, at lower Mg content, the graphite appears in lamellar morphology [1, 2]. Once different graphite morphologies are obtained, the thermo-physical properties will be measured. 

    It was found that nodularity decreases linearly with the time that the alloy stays over the liquidus temperature. Nevertheless, to times longer than 80 min, the nodularity decreases slower, showing, and exponential variation. Thermal conductivity decreases abruptly when the graphite changes from lamellar to 5% of nodularity, then continues decreasing slower when the nodularity increases. 

    The conductivity of LGI decreases when the temperature increases while to CGI and SGI, the conductivity increases with temperature until it reaches a maximum, then the conductivity starts to decrease. The differences between LGI, CGI, and SGI conductivity shorten as temperature increases. 

    Download (pdf)
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  • 28.
    Amieva Llavona, Jose Manuel
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Influence of Molybdenum on mechanical and thermal properties in lamellar graphite cast iron2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In this work hypoeutectic lamellar graphite iron alloyed with seven different levels of molybdenum was studied in order to characterize its thermal and mechanical properties. Several tests were conducted and experimental data was collected from, laser flash (LFA), differential scanning calorimeter (DSC), dilatometer and tensile test.

    Micrographs taken from the polished specimens were captured and studied through quantitative measurements of several parameters, e.g. graphite fraction, shape, form. Afterward, the same samples were colour etched with picric acid in order to perform a qualitative analysis of the matrix.

    It was concluded from the data collected, that molybdenum has a significant influence in the UTS. Such influence, increases the UTS strongly with the amount of molybdenum. It was also found that the pearlitic matrix changes into ausferrite matrix, for the 0.96% of molybdenum, but ausferrite it is detected from 0.65% of molybdenum onwards. Regarding thermal properties, molybdenum does not have noticeable effect but it is possible to see a clear worsen in the conductivity in the specimen, which has ausferrite as matrix.

    Graphite does not seem to have a clear behavior with the different concentration of molybdenum but in the other hand, the matrix shows clear differences as it was mention before.

    During solid state reaction, it was detected a clear influence of molybdenum additions, where the latent heat and the volumetric change were measured during the eutectoid reaction and show a decreasing behavior for molybdenum contents above 0.65%.

  • 29.
    Anderfelt, Filip
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Äse, David
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Methodology for Obtaining S-N Curves using Fatigue Testing and Static FEA2022Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The use of recommended S-N curves, presented in current literature, to analyse and determine the fatigue life of a part is common practice in, inter alia, the construction industry.However, the recommended S-N curves are generally created for larger components used in mainly the construction industry. Hence, the use of S-N curves for the evaluation of smaller parts, may result in over-dimensioning of such parts. For this reason, evaluation and designing of smaller parts could benefit from the development of an in house S-N curve specific for the part.

    The purpose of this thesis is to generate and validate an in-house method for creating a S-N curve, for a specific part to be compared with recommended S-N curves in the literature. The specific part used for the generating of the method is a welded steel joint with the geometry of two steel pipes, welded together in a t-formation and which has been provided by Thule AB for the purpose of the thesis.

    The method presented uses the results from 1) physical fatigue tests using a fatigue testing machine and 2) static FEA to derive a S-N curve for the specific part using the least squares method. A fatigue testing rig enables the gathering of data of the number of cycles to failure when the part is subject to a given cyclic load. The rig uses pneumatics to control the forces applied onto the part with the use of a cylinder. Furthermore, the fatigue testing rig was designed to be controlled by the applied force, meaning, that the rig ensured a homogeneous load cycle by measuring the force from a load cell and alternating the direction of the cylinder with an electrically controlled pressure valve. The performance of static FEA evaluations aim at locating stresses in the part. For this thesis the stresses were evaluated using the hot spot method due to the part's welded geometry.

    The data gathered from the physical fatigue tests and the static FEA evaluations are subsequently combined deriving S-N curves applicable to the part.

    From the fatigue tests and FEA evaluations for the t-shaped welded steel part, four S-N curves were derived of which two curves showed the results of a linear fitted curve whereas the other curves used the recommended slope of $-1/3$. The results showed that the S-N curves derived, using a set slope, resulted in similar curves to the recommended S-N curve provided by the literature. However, the linear fitted S-N curve showed that the part, according to the S-N curve, had a higher fatigue resistance than recommended.

     Due to limitations in the thesis work, the S-N curves derived within the framework of this thesis should be regarded as theoretical and have been strictly used to identify whether the method generated is applicable for deriving of S-N curves.

    Fulltekst (pdf)
    fulltext
  • 30.
    Andersson, Mattias
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Thermal Fatigue in low carbon steel2022Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Large caliber gun barrels are exposed to deferent kinds of high strain, from pressure to wear, with influence of chemical, and thermal effects. With the ever increasing demand on better guns, the demand on the barrel increases as well. This study will go through the thermal part of the strain that affect the gun barrel steel. The will be experiment on how thermal cyclic load affect low alloy steel, documentation the cracks, hardness and create computer simulations on the physical experiments.

    The heating experiment is carried though by the help of an induction coil that is the supplement for the burring propellant to not get any unwanted chemical residue. The heat and timeframe of one cycle, does not one hundred percent representative the reality but it will still give a got comparison of the materials tested. The experiment was completed on five different material 1.2709-A1, -A2, -B, CrMoV, and H13, which are all used in the tooling industry and therefore interesting material in a gun barrel.

    The material show vastly different cracks intensity and crack length, with is connected to grain size, thermal conductivity, coefficient of the thermal expansion, strength, toughness, and hardness. The hardness measurement showed a phenomena that does not happen in a fired gun barrel, which is thermal softening. Thermal softening happens in this test for the simple reason that the temperate was never high enough to make the steel phase change to austenite. This makes the secondary carbide crystals to recrystallize into larger ones to lower their energy, in turn reducing hardness and strength. The simulations show that there is tensile stress at the outside, closest to the induction coil, and compressive stress on the inside of the test sample. It also gave a good insight on how the properties affect the steel. 

    The material 1.2709B got the best results from the experiment conducted in the study, few and short cracks, almost nonexistent hardness softening. It has the ductility and toughness to reduce the softening and the strength and thermal conductivity to stand against the major crack formations.

  • 31.
    Andersson, Nils-Eric
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    High speed machine metallic structures NFFP-344 WE 2.2.2002Rapport (Annet vitenskapelig)
  • 32.
    Andersson, Nils-Eric
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik. Komponentteknologi.
    Structure and properties of thick plate and near surface properties after high speed machining af AA70102003Doktoravhandling, monografi (Annet vitenskapelig)
  • 33.
    Andersson, Nils-Eric
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik. Komponentteknologi.
    Structure and properties of thick plates of 70101998Licentiatavhandling, monografi (Annet vitenskapelig)
  • 34.
    Andersson, Petter
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Belysningslära.
    Petersson, Marcus
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Belysningslära.
    En undersökning av projicerat ljus i inomhusmiljö2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Fulltekst (pdf)
    En undersökning av projicerat ljus i inomhusmiljö
  • 35.
    Andriollo, Tito
    et al.
    Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
    Hellström, Kristina
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Sonne, Mads R.
    Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
    Thorborg, Jesper
    Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
    Tiedje, Niels
    Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
    Hattel, Jesper
    Department of Mechanical Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
    Uncovering the local inelastic interactions during manufacture of ductile cast iron: How the substructure of the graphite particles can induce residual stress concentrations in the matrix2018Inngår i: Journal of the mechanics and physics of solids, ISSN 0022-5096, E-ISSN 1873-4782, Vol. 111, s. 333-357Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recent X-ray diffraction (XRD) measurements have revealed that plastic deformation and a residual elastic strain field can be present around the graphite particles in ductile cast iron after manufacturing, probably due to some local mismatch in thermal contraction. However, as only one component of the elastic strain tensor could be obtained from the XRD data, the shape and magnitude of the associated residual stress field have remained unknown. To compensate for this and to provide theoretical insight into this unexplored topic, a combined experimental-numerical approach is presented in this paper. First, a material equivalent to the ductile cast iron matrix is manufactured and subjected to dilatometric and high-temperature tensile tests. Subsequently, a two-scale hierarchical top-down model is devised, calibrated on the basis of the collected data and used to simulate the interaction between the graphite particles and the matrix during manufacturing of the industrial part considered in the XRD study. The model indicates that, besides the viscoplastic deformation of the matrix, the effect of the inelastic deformation of the graphite has to be considered to explain the magnitude of the XRD strain. Moreover, the model shows that the large elastic strain perturbations recorded with XRD close to the graphite–matrix interface are not artifacts due to e.g. sharp gradients in chemical composition, but correspond to residual stress concentrations induced by the conical sectors forming the internal structure of the graphite particles. In contrast to common belief, these results thus suggest that ductile cast iron parts cannot be considered, in general, as stress-free at the microstructural scale. 

  • 36.
    Apelstedt, Kristoffer
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    Dahl, Andreas
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Maskinteknik.
    Utveckling av motocrossadel2008Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Fulltekst (pdf)
    FULLTEXT01
  • 37.
    Appusamy Boopathy, Harish
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Bonthala, Pavan Kumar
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Electrochemical etching and anodizing as key stages of surface treatment of aluminium foil for electrolytic capacitor industry: Application of Electro Chemical Impedance Spectroscopy as non-destructive characterization of etched anode foil with an anodized dielectric oxide layer2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In the initial stage, the sample preparation was done by using the techniques of Anodic etching and anodic forming processes where a repeated trial and error method of sample preparation headed towards making out a suitable sample set for characterization. After this step, the set of 2 different industrial samples were introduced and anodic oxide forming process was carried out in different electrolytes.

     

     In the sample preparations, 4 different electrolytes were used 15% wt. Ammonium Adiphate, 1.5% wt. Ammonium Phosphate, 7% wt. Boric acid and 15% Penta Borate at different stages for performing the anodic oxide forming process. Minimum forming voltages of 20V to a maximum of 100V was employed in the sample preparation and to overcome the waiting time in forming the etched samples a higher current of 0.5A was used.

     

    After the samples preparation, Electrochemical Impedance spectroscopy was used as a tool for characterising the various groups of samples and for observing the micro structures of various samples, they were fractured and the observed on the cross section by SEM.

     

    After the analysis of the etched samples was made, an attempt to compare the results of the data of these samples to that of the 2 set of industrial samples was made and found that the resultant data wasn’t stable enough to characterize since huge scattering were occurring and whereby the simulation of the CPE circuit for the chosen circuit in the analysis was not possible.

     

    Under the analysis, a randomly chosen industrial sample was also used and the resultant data was utilised in understanding the response of the system to different electrolytes.

    Fulltekst (pdf)
    fulltext
  • 38.
    Armanjo, Jahanmehr
    Högskolan i Jönköping, Tekniska Högskolan. j@armanjo.se.
    The influence of microstructural deformations and defects on mechanical properties in cast aluminium components by using Digital Image Correlation Techniques (DICT)2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Digital image correlation techniques (DICT), a non-contact deformation measuring technique based on gray value digital images, have become increasingly used over the last years. By using the DIC technique during a tensile test, the deformation behavior of different engineering material under an applied load can be determined and analyzed. Digital images, acquired from a tensile test, can be correlated by using DICT software and from that the local or global mechanical properties can be calculated. The local or global mechanical properties determination of a flat test specimens are based on the displacements or changes in a previous stochastic sprayed or natural pattern.

    The used material for this purpose is cast silicon (Si) based aluminium (Al) component, designated as AlSi7Mg0.3 (Anticorodal-78 dv). The hypoeutectic Al- Si alloy is widely applicable for engine constructions, vehicle and aerospace constructions, shipbuilding, electrical engineering and constructions for food industry.

    There are many microstructural parameters in a binary system Al- Si alloys, which the mechanical properties can be depended on, for instance phase distribution, Secondary Dendrite Arm Spacing (SDAS), morphology of Si particles (Roundness) and microscopic defects or pores. All these parameters can contribute to enhance the proper mechanical performance (e.g. Strength and ductility) in the Al-Si cast components.

    Fulltekst (pdf)
    fulltext
  • 39.
    Arvidsson, Lukas
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Industriell produktutveckling, produktion och design.
    Goncin, Dennis
    Jönköping University, Tekniska Högskolan, JTH, Industriell produktutveckling, produktion och design.
    Karusellsvarvs-magasin: En lösning för 150+ verktyg2022Independent thesis Basic level (university diploma), 80 poäng / 120 hpOppgave
    Abstract [sv]

    Sammanfattning

    Syfte – Syftet med studien är att ta fram en metod för att bevara ett stort antal verktyg för enstörre bearbetningsmaskin med en lösning för verktygsbyte. Frågeställningar sammanställdesgenom personlig kommunikation och kravspecifikationer som MFAB begärt.

    Metod – För att ta fram och producera koncept användes flera metoder som beskrivs i Produktutveckling – Effektiva metoder för konstruktion och design av Johannesson, Perssonoch Pettersson. Koncepten som skapats värderas mot krav i form av en Pughs matris.

    Resultat – I en informationssamling som utförs i förstudien samlas information om dagensvanligaste magasinlösning för fräs- och svarvmaskiner. Trum- och linjärmagasinet är devanligaste lösningarna för dagens bearbetningsmaskiner. Ett visuellt koncept beskrivs med hjälp CAD-programmet det är designat i samt en beskrivandetext för varje del. Det färdiga konceptet inkluderar:• En inhägnad för att hålla alla delar inom den förbestämda arbetsytan.• En serviceport för smidigt byte av verktyg utanför användning av magasinet.• Lösning för underhåll så att en person kan komma åt inuti magasinet.• Hyllor som agerar magasin då de håller verktygen som maskinen inte använder förtillfället.• En kedja som hyllorna är fästa på som roterar så att hyllorna kan nå dit de är behövda.• En linjärenhet som hämtar verktygen från hyllorna och lämnar vidare dem tillbufferten.• Bufferten som håller ett visst antal verktyg som maskinen är i behov av snart.• Restupplockning som tar hand om eventuellt skräp som kan förekomma på verktygen.Med dessa delar kan frågeställningarna besvaras.

    Begränsningar – Två begränsningar i studien har påträffats. Den första begränsningen varatt i konstruktionen gick mer plats åt till magasinet än vad som ursprungligen hade beräknatsför. Nästa begränsning var att storleken av studien över den givna tiden som projektet varadebegränsade möjligheten att fullt utveckla det slutgiltiga konceptet.

    Nyckelord – Bearbetningsmaskin, Automation, Magasin, Verktygshantering, Konstruktion, Skyddsinhägnad, Produktutveckling

    Fulltekst (pdf)
    Karusellsvarvs-magasin
  • 40.
    Ashrafi, Hamid
    et al.
    Faculty of Chemical and Materials Engineering, Shahrood University of Technology, Shahrood, Iran.
    Shamanian, Morteza
    Department of Materials Engineering, Isfahan University of Technology, Isfahan, 8415683111, Iran.
    Emadi, Rahmatollah
    Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
    Aghili, Sayyed Erfan
    Materials Engineering Group, Golpayegan College of Engineering, Isfahan University of Technology, Golpayegan, Iran.
    Ghassemali, Ehsan
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Damage Micromechanisms in Friction Stir-Welded DP600 Steel during Uniaxial Tensile Deformation2022Inngår i: Journal of materials engineering and performance (Print), ISSN 1059-9495, E-ISSN 1544-1024, Vol. 31, s. 10044-10053Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, damage initiation micromechanisms in friction stir-welded DP600 steel sheets during tensile deformation were studied by scanning electron microscopy (SEM) and electron backscatter diffraction. For this purpose, DP600 steel was welded using friction stir welding with two combinations of rotational and transverse speed, to prepare joints with low and high heats. Microhardness measurements on the cross section of the weldments revealed the formation of a softened zone in the HAZ as a result of the tempering of the martensite, which led to the localization of strain and failure during the tensile testing. SEM observations on the cross section of tensile tested specimens showed that ferrite–martensite interface decohesion and martensite fracture are the main void nucleation mechanisms in the DP600 steel. For the sample welded with low heat input, ferrite–martensite interface decohesion started at higher strains compared to the DP600 steel. A new void initiation mechanism including plastic deformation of tempered martensite, necking, separation of martensite fragments and formation of a void between the separated segments was also suggested for this sample. For the sample welded with high heat input, formation of void at the ferrite–cementite interface was the main void nucleation mechanism and ferrite–martensite interface decohesion was an inactive mechanism.

  • 41.
    Ashrafi, Hamid
    et al.
    Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
    Shamanian, Morteza
    Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
    Emadi, Rahmatollah
    Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
    Ghassemali, Ehsan
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Void formation and plastic deformation mechanism of a cold-rolled dual-phase steel during tension2020Inngår i: Acta Metallurgica Sinica (English Letters), ISSN 1006-7191, E-ISSN 2194-1289, Vol. 33, s. 299-306Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The void formation and plastic deformation micromechanisms of a cold-rolled DP600 steel during tensile loading were studied by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The SEM observations revealed that the main void nucleation mechanism in the DP600 steel is decohesion at the ferrite–martensite interfaces. The voids were mostly observed between the closely spaced martensite islands situated at the boundaries of relatively finer ferrite grains. The EBSD results indicated a strain gradient developed from the ferrite–martensite and ferrite–ferrite interfaces into the interior of ferrite grains during the tensile deformation, which led to a stress concentration at these interfaces. Moreover, it was demonstrated that local misorientation inside the finer ferrite grains surrounded by martensite islands was higher than that for the coarser ferrite grains, which made the former more prone to void initiation.

  • 42.
    Atefi, S.
    et al.
    Univ Tehran, Sch Met & Mat Engn, Coll Engn, Tehran 111554563, Iran..
    Parsa, M. H.
    Univ Tehran, Sch Met & Mat Engn, Coll Engn, Tehran 111554563, Iran.;Univ Tehran, Sch Met & Mat Engn, Ctr Excellence Low Energy Consumpt Mat, Tehran, Iran..
    Ahmadkhaniha, Donya
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. Jonkoping Univ, Sch Engn, Dept Mat & Mfg, Jonkoping, Sweden..
    Zanella, Caterina
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning. Jonkoping Univ, Sch Engn, Dept Mat & Mfg, Jonkoping, Sweden..
    Jafarian, H. R.
    Iran Univ Sci & Technol IUST, Sch Met & Mat Engn, Tehran 1684613114, Iran..
    A study on microstructure development and mechanical properties of pure copper subjected to severe plastic deformation by the ECAP-Conform process2022Inngår i: JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T, ISSN 2238-7854, Vol. 21, s. 1614-1629Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Commercially pure copper rod was successfully subjected to severe plastic deformation by applying the continuous equal channel angular pressing (ECAP-Conform) method at room temperature. Microstructural characterizations of copper rod samples at various stages of plastic deformation were carried out by optical microscopy and electron backscatter diffraction methods. X-ray diffractometry and Kernal average misorientation were used for dislocation density estimations. Microstructural evaluations revealed grain size change of 30 mm for the initial annealed copper rod to less than 5 mm and even 100 nm for severely deformed samples. Mechanical behaviors of samples after different deformation stages were characterized using tensile and hardness tests. The ultimate tensile strength of the severely deformed copper rod was increased threefold by ECAP-Conform while elongation halved in comparison to the initial annealed copper. Low-temperature annealing of severely plastic deformed samples led to bi-modal grain size distribution and lowering of strength accompanied by the increase of elongation. Tensile properties of severely deformed and then annealed copper samples showed around a 40% increase in both ultimate tensile strength and elongation in comparison to the initial annealed copper rod.

  • 43.
    Atokaran, Albin Johny
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Implementation and Calibration of Material Property Prediction COMSOL Model for Cylindrical Castings of Pearlitic Lamellar Graphite Iron2021Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 44.
    Awe, Samuel A.
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Jarfors, Anders E. W.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Dahle, Arne
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Development of cast Al-Cu-Si ternary eutectic alloys for high temperature applications2016Inngår i: Proceedings and Abstracts Book of European Advanced Materials Congress, At Stockholm, Sweden / [ed] Ashutosh Tiwari, Linköping: VBRI Press , 2016Konferansepaper (Fagfellevurdert)
    Fulltekst (pdf)
    Abstract
  • 45.
    Awe, Samuel A.
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Jarfors, Anders E.W.
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Lee, Young C.
    Dahle, Arne
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Development of new Al-Cu-Si alloys for high temperature performance2017Inngår i: Advanced Materials Letters, ISSN 0976-3961, E-ISSN 0976-397X, Vol. 8, nr 6, s. 695-701Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a quest to develop new light metal alloys that can perform excellently at elevated-temperatures (from 300°C to 400°C), a ternary eutectic Al-Cu-Si alloy was exploited to gain a deeper understanding of the alloy system and its suitability for high temperature applications. The alloys studied, with chemical composition of Al-27%Cu-5%Si (by weight percent) with Ni addition in the range of 0 to 1.5%wt, were cast in a rapid solidification casting technique. The solidification characteristics of the alloy was studied using the Thermo-Calc software. Microstructures were characterized in a scanning electron microscope coupled with energy dispersive spectrometry (SEM-EDS). Finally, the elevated-temperatures tensile properties of the alloys were investigated. Comparing the microstructures and mechanical properties of these Al-Cu-Si(-Ni) alloys with conventional Al-Si alloy A319, the refined microstructure with dispersed Ni intermetallic particles formed in the as-cast Al-Cu-Si(-Ni) alloys deliver improved elevated temperature properties. In particular, the yield strength and ultimate tensile strength of the new alloy with 1.5% Ni at 400?C were observed to be 220% and 309% higher, respectively, than for conventional A319 alloy.

  • 46.
    Aziziderouei, Mona
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    The influence of Strontium level on the microstructure formations and mechanical properties of Al-Si alloys2013Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Abstract

    The aim of this thesis is to investigate the influence of Strontium (Sr) addition on the microstructure formation, including porosity and the mechanical properties of commercial Aluminum alloy ENAC 46000. In addition, it is intended to obtain an optimum Sr level in order to achieve the desired mechanical properties.

    Specimens were prepared with gradient solidification technique at different cooling rates in order to achieve samples with a variety of microstructural coarseness. Beside microstructural and mechanical properties studies, thermal analysis was employed to keep track of the time and temperature of phases during solidification.

    The achieved results indicate that Sr affects the mechanical properties except the strength. The analysis of the result indicates that the optimum level of Sr is 150 ppm.

    Porosity is a function of both Sr addition and cooling rate. Comparing the influence of cooling rate with Sr addition on the amount of porosity shows that the cooling rate can modify the ENAC 46000 alloy more than Sr addition.

    Thermal analysis technique used to study effect of phase formation on modification. Influence of solidification rate and Sr level on time and temperature of α-Al (Τ_α) and Al-Si eutectic (Τ_N) nucleation was observed.

  • 47.
    Bagare, Vinay Shrinivas
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling.
    Study on wear modelling using pilot jaw crusher2017Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    The crushers are used by mining and aggregate industries for crushing the rocks. Wear in these crushers wear parts causes a great wear loss and significant economic loss. This work aims to find the worn geometry, hardness and behavior of the wear parts as function of rock type.To perform this research, a series of tests such as scratch test, rock-crushing test, microstructural analysis and hardness test were carried out. From the scratch test, hardness test and microstructural analysis, wear mechanism and work hardening effects were studied using LOM, SEM and Vickers hardness measurement. The crushing test was carried out by crushing quartzite, diabase and gneiss rocks in a mini jaw crusher with respect to M1, M2 and M7 samples proposed by the company, which provides data to calculate volumetric loss, wear ratio and data for power consumption. The data collected from the experiments are used to create model to get a clear picture of the performance of each material with respect to different rock type.During pouring the rocks into the jaw crusher, several types of wear are expected to be occur, which substantially results in change of the geometry of the jaw crusher plates and hence the performance of the crusher will be affected. Controlling of such harsh wear situations requires introducing a material with high-performance wear resistance (particularly abrasion) and fundamentally modifying the operating conditions to minimize the risk of severe wear degradation. For this reason, it is desirable to simulate how the geometry and performance are changing due to wear.The results from the scratch test and microstructural analysis showed that at low applied loads severe plastic deformation is seen but as the load increases, the work hardening mechanism develops and provides wear resistance properties. The results from hardness test and modeling, M7 sample shows good wear resistance properties against hard and abrasive rocks which in this case is diabase and quartzite rocks, M2 sample shows good wear resistance against only quartzite rocks and gneiss rocks. M1 sample shows less volumetric loss against quartzite but when compared to M2 and M7’s mechanical property, M1 showed low wear resistance against all three rocks.

    Key words: Wear mechanism, work hardening, wear ratio, volumetric loss, power consumption, M1, M2, M7 samples, quartzite, diabase and gneiss rock.

  • 48. Bakowski, M.
    et al.
    Nee, H.-P.
    Belov, Ilja
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning - Ytteknik.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning - Ytteknik.
    High temperature electronic systems all in silicon carbide (SiC) for electric vehicles2011Inngår i: Workshop för 'Banbrytande IKT 2007, VINNOVA, Stockholm, 1 September 2011, 2011Konferansepaper (Annet vitenskapelig)
  • 49. Bakowski, Mietek
    et al.
    Nee, Hans-Peter
    Zetterling, Carl-Mikael
    Belov, Ilja
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning - Ytteknik.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning - Ytteknik.
    High temperature electronic systems all in silicon carbide for hybrid and electrical vehicles2015Inngår i: International SiC Power Electronics Applications Workshop, ISiCPEAW 2015, 2015Konferansepaper (Annet vitenskapelig)
  • 50.
    Balachandran Padmaja, Kailas Chandran
    et al.
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    Behera, Abhisek
    Jönköping University, Tekniska Högskolan, JTH, Material och tillverkning.
    EMPIRICAL MODELLING OF THERMAL AND TENSILE PROPERTY FORMATION IN NODULAR CAST IRON2021Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Owing to its many qualities, cast iron is one of the most commonly utilized materials in the industry. Cast iron having graphite spheroids scattered throughout the matrix is referred to as Ductile cast iron or Spheroidal graphite iron (SGI). The mechanical and thermo-physical properties of ductile iron are influenced by the microstructure phases that constitute the metallic matrix as well as the number, the size, and the nodularity of the graphite particles. Casting industries face challenges to optimize the shape and size of their casting components to reduce environmental impact and increase their performance. They also employ numerical simulation software for casting process simulation and material property prediction, as part of product development. Reliable material property models constitute an important prerequisite for cast component simulation. The microstructure of SGI can be adjusted by varying cooling conditions and the chemical composition. The purpose of this thesis is to investigate how the cooling rate and the carbon content influences the microstructure morphology and the mechanical and thermal properties of SGI. Five different cooling rates and two different carbon contents (hypereutectic and hypoeutectic) were utilized in this thesis. The results show that the mechanical and thermal properties do not depend on the cooling rates, as long as the matrix microstructure (ferrite/pearlite ratio) remain similar. Furthermore, the different carbon contents have no sizeable impact on the different microstructure features and consequently on the mechanical and thermal properties. The microstructure investigation shows that the increase in the cooling rate results in a significant increase of small graphite nodules at the thermal center of the castings. This observation indicates a secondary nucleation event at the last to solidify areas and requires further investigation. 

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