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  • 1.
    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 strength2019Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Uppsatsen syfte är att öka förståelsen och föreslå nya värmebehandlingsparametrar för att förbättra gigacykelutmattningsegenskaperna för austempererat segjärn (ADI). Arbetet utfördes hos gruv- och infrastrukturföretaget Epiroc där de tidigare undersökt gigacykelutmattnings-egenskaper för ADI men endast för ett värmebehandlingsrecept. Utmattningsegenskaperna för ADI har undersökts akademiskt i stor utsträckning men då framförallt i låg- till högcykelområdet (≤108 cykler) med endast ett fåtal studier i gigacykelområdet (>108 cykler). Därför baserades arbetet på tesen: ’förbättringar i högcykelutmattning bör ge en förbättring vid gigacykelutmatning’. Den tesen möjliggör nyttjande av större mängd publicerad forskning som genomförts i området för värmebehandlingens inverkan på högcykelutmattning (>107 cykler).

    För att effektivt kunna utföra värmebehandlingsexperiment på den Cu-Ni-Mo legerade segjärnet var det kritisk att finna material- och mekaniska egenskaper som kännetecknar hög högcykelutmattningsgräns. Potentialen att kunna nyttja dessa egenskaper nyttjas för experimentering med värmebehandling men samtidigt hålla nere mängden utmattningsprov är hög.

    Identifiering av de kritiska värmebehandlingsparameterana (och parameterområdena) som visades ge hög högcykelutmattningsstyrka var de första steget, vilka är: Austempereringstemperatur (Taus), austempereringstid (taus), och austenitiseringstemperatur (Tγ). Hög dukilitet, slagseghet (onotchat) och hög volymfraktion kolstabiliserad austenit identifierades som de mekaniska och material-egenskaper som var karaktäriserande för dessa väl presterande material i högcykelutmattning. Med värmebehandlingsparameterar, material- och mekaniska egenskaper utmärkande för hög högcykelutmattningsgräns utvecklades en experimentell testserie baserat på faktoriell design (23). Metodiken valdes för sin enkelhet och styrka, framförallt att kunna se effekten av både de individuella värmebehandlingsparameterna men även interaktionseffekterna mellan dem. För varje parameter (23) testas två nivåer (23), en hög och en låg vilket resulterar i totalt 8 olika värmebehandlingsförsök. Svarsvariablerna som utvärderas för varje värmebehandlingsförsök var primärt dukilitet, slagseghet och volymfraktion kolstabiliserad austenit. Vilket medger att följande provning utfördes på de 8 test materialen: dragprov, slagprov, röntgendiffraktion. Råmaterial för värmebehandling och provning gjöts av ett kommersiellt gjuteri i form av Y-block typ III med kemisk sammansättning enligt Epiroc’s specifikation. Provresultaten i form av individuella och interaktionseffekter bedömdes både grafiskt och beräknades fram samt att resultaten validerades genom jämförelse med resultat från litteraturen. Bra överrensstämmelse mellan de experimentella resultaten i arbetet och jämförd litteratur sågs för denna kemiska sammansättning. Slutligen föreslogs en ny uppsättning värmebehandlingsparameterar för ökad högcykelutmattningsgräns.

  • 2.
    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 coatings2018Ingår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 769, s. 1080-1087Artikel i tidskrift (Refereegranskat)
    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.

    Publikationen är tillgänglig i fulltext från 2020-08-04 00:00
  • 3.
    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 Mg2017Konferensbidrag (Refereegranskat)
    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.

  • 4.
    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 Mg2018Ingår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 53, nr 24, s. 16585-16597Artikel i tidskrift (Refereegranskat)
    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. 

  • 5.
    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 particles2017Konferensbidrag (Övrigt vetenskapligt)
    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.

  • 6.
    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 coatings2019Ingår i: Coatings, ISSN 2079-6412, Vol. 9, nr 9, artikel-id 554Artikel i tidskrift (Refereegranskat)
    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. 

  • 7.
    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 arrays2018Ingår i: St. Petersburg Polytechnical University Journal: Physics and Mathematics, ISSN 2405-7223, Vol. 11, nr 3, s. 39-51Artikel i tidskrift (Refereegranskat)
    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.

  • 8.
    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 ashes2017Ingår i: European Journal of Glass Science and Techology. Part B. Physics and Chemistry of Glasses, ISSN 1753-3562, Vol. 58, nr 6, s. 231-236Artikel i tidskrift (Refereegranskat)
    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.

  • 9.
    Alonso, Patricia
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Effect of graphite morphology on the thermo-physical properties in cast iron2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    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. 

  • 10.
    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 iron2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    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%.

  • 11.
    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 matrix2018Ingår i: Journal of the mechanics and physics of solids, ISSN 0022-5096, E-ISSN 1873-4782, Vol. 111, s. 333-357Artikel i tidskrift (Refereegranskat)
    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. 

  • 12.
    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 layer2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Sammanfattning

     

    Avhandlingsarbetet har genomförts på KEMET AB i samarbete med yttekniklaboratoriet vid JTH i syfte att karakterisera den etsade anodiska aluminiumfolien som grundprov med anodisering och etsning för ytbehandling.

     

    I inledningsskedet gjordes provberedningen med användning av teknikerna för anodisk etsning och anodbildande processer där en upprepad provnings- och felmetod för provberedning ledde ut mot att utarbeta en lämplig provuppsättning med avseende på karakterisering. Efter detta steg infördes uppsättningen av 2 olika industriella prover och anodoxidbildande process utfördes i olika elektrolyter.

     

    I provpreparaten användes 4 olika elektrolyter 15 % vikt Ammoniumadiphat, 1,5 vikt% Ammoniumfosfat, 7 vikt% Borsyra och 15 % Penta-borat vid olika steg för utförande av anodoxidbildningsförfarandet. Minimala formningsspänningar på 20V till ett maximum av 100V användes i provframställningen och för att övervinna väntetiden vid bildning av de etsade proven användes en högre ström av 0,5A.

     

    Efter provberedningen användes elektrokemisk impedansspektroskopi som ett verktyg för att karakterisera de olika grupperna av prover och för att observera mikrostrukturerna i olika prover, de bröts och de observerades i tvärsnittet av SEM.

     

    Efter att analysen av de etsade proverna gjordes ett försök att jämföra resultaten av data från dessa prover till den för de två uppsättningarna av industriella prover.

    Det är konstaterat att de resulterande data inte var stabila nog att karakterisera eftersom stor spridning inträffade och varigenom simuleringen av CPE-kretsen för den valda kretsen i analysen inte var möjlig.

     

    Under analysen användes också ett slumpmässigt valt industriellt prov och de resulterande data användes för att förstå systemets respons till olika elektrolyter.

  • 13.
    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
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Void formation and plastic deformation mechanism of a cold-rolled dual-phase steel during tension2019Ingår i: Acta Metallurgica Sinica (English Letters), ISSN 1006-7191, E-ISSN 2194-1289Artikel i tidskrift (Refereegranskat)
    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.

  • 14.
    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 applications2016Ingår i: Proceedings and Abstracts Book of European Advanced Materials Congress, At Stockholm, Sweden / [ed] Ashutosh Tiwari, Linköping: VBRI Press , 2016Konferensbidrag (Refereegranskat)
  • 15.
    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 performance2017Ingår i: Advanced Materials Letters, ISSN 0976-3961, E-ISSN 0976-397X, Vol. 8, nr 6, s. 695-701Artikel i tidskrift (Refereegranskat)
    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.

  • 16.
    Beckius, Fredrik
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling.
    Gustafsson, Robin
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling.
    Connecting casting simulation and FE software including local variation of physical properties.: Investigation on local material properties and microstructure in a grey iron cylinder head.2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 17.
    Belov, Ilja
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning - Ytteknik.
    Reliability study of GaN HEMTs2016Konferensbidrag (Övrigt vetenskapligt)
  • 18.
    Belov, Ilja
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Alavizadeh, Zahra
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Lindgren, Mats
    Omnisys Instruments AB, Västra Frölunda, Sweden.
    Ryden, Jan
    Saab AB, Göteborg, Sweden.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. RISE Research Institutes of Sweden, Borås, Sweden.
    Experimental and CFD evaluation of active anti-condensation methods for non-hermetic cabinets2018Ingår i: 19th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE, 2018, Institute of Electrical and Electronics Engineers (IEEE), 2018, s. 1-6Konferensbidrag (Refereegranskat)
    Abstract [en]

    Experimental evaluation of several active anti-condensation methods for application in non-hermetic electronics enclosures was performed in harsh climatic conditions, including RH = 70% and T = 43 °C. The studied methods included blowing the air along the exposed surface, combination of blowing and air heating as well as local heating of the exposed surface in natural convection conditions. The purpose was to prevent/remove the dew on/from the exposed surface of a micro-condensation sensor. The difference between the methods was quantified in terms of time for dew removal. The power consumption aspects were discussed. A CFD based optimization methodology was developed to determine the heating profiles for the local anti-condensation PCB heater in a non-hermetic cabinet exposed to the quickly changing climatic conditions. The potential for 60% energy savings was revealed by simulation.

  • 19.
    Belov, Ilja
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Nordh, Andreas
    Salomonsson, Kent
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Produktutveckling.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Fin‐Tube and Plate Heat Exchangers: Evaluation of Transient Performance2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    A methodology for evaluation of transient performance of, and comparison between plate heat exchanger and plate-fin-and-tube heat exchanger was developed and realized, including experiment and 3-D simulation. Heat transfer from water to a gas medium was addressed. The heated gas volume was the same for both heat exchanger designs. This was achieved by placing the plate-fin-and-tube heat exchanger into enclosure. The volume average temperature of the gas as function of time was computed. Estimated material cost for the studied designs was at least seven times lower than for the stainless steel plate heat exchanger. The performance of the selected plate-fin-and-tube heat exchanger design was found comparable to the plate heat exchanger, when both fin and tube materials were set to Al, and the enclosure was a light-weight thermal insulator. Transient behavior of the studied heat exchangers should be of interest for micro-grid applications, but also for thermal management in electronic cabinets and data centers.

  • 20.
    Belov, Vladimir
    et al.
    Ogarev Mordovia State University, Saransk, Russian Federation.
    Leisner, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. RISE, Swedish Research Institute, Safety and Transport/Electronics, Borås, Sweden.
    Mannikoff, Anders
    Herrljunga Elektriska AB, Herrljunga, Sweden.
    Belov, Ilja
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Mathematical Model of Multi-Phase Power Converter for Parallel Computation2018Ingår i: International Journal of Emerging Electric Power Systems, ISSN 2194-5756, E-ISSN 1553-779X, Vol. 19, nr 1, artikel-id 20170114Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A mathematical model of a multi-phase power conversion system composed of modified bridge-elements (B-system) capable for parallel computation has been developed. Experimental validation on the example of a power system including a synchronous generator and an AC-DC rectifier has been performed. A mathematical algorithm for B-system assembly and steps to obtain mathematical model of the B-system have been developed. Integration of mathematical models of conversion system into the complete model of a multi-phase power system has been explained and evaluation of computational efficiency of parallel computation techniques for the developed model of an AC-DC-AC converter has been performed. The presented modelling method can be employed in the design phase of smart grids, for power quality and conducted emission analysis. 

  • 21.
    Bhat, Abhishek Govind
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Thermodynamic apporach for reduction of solag amount and viscosity in CGI production process2018Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The work presented aims to reduce the amount and viscosity of the slag produced in the furnace during the production of Compacted Graphite Iron in SCANIA foundry and simulate the actual process using thermodynamic calculations to estimate the amount and the composition of the slag.

    The estimation of slag amount and slag compositions was done using CALPHAD (Calculation of Phase Diagram) method which can be done using the thermodynamic software Thermo-Calc using the composition of the raw materials and the phase diagrams calculation. In the present work, an appropriate calculation method to estimate the amount and composition of slag was established and based on the calculations, strategies to decrease the viscosity were suggested.

  • 22.
    Bjurenstedt, Anton
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    On the influence of imperfections on microstructure and properties of recycled Al-Si casting alloys2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Genom att återvinna aluminium kan stora energibesparingar göras eftersom återvinning kan förbruka så lite som 5% av den energi som behövs för produktion av primär aluminium. Vid gjutning av högkvalitativa aluminiumprodukter krävs förståelse för defekter i mikrostrukturen och denna kunskap är extra viktig vid användning av återvunnen aluminium, som i regel innehåller mer defekter än primär aluminium. Defekterna består bland annat av Si, Fe och Mn samt oxider. Si behövs för gjutbarhet men kan också initiera brott. Järnrika intermetaller kan ha olika morfologier som generellt påverkar gjutna komponenter negativt. Oxider, som kan utgöra sprickor, är gäckande då de är svåra att kvantifiera.

    Denna avhandlings syfte är att öka kunskapen om defekter i gjutna komponenter av återvunnen aluminium. Experiment utfördes med avancerad laborationsutrustning så som röntgenfotografering av prover under stelning och dragprovning i svepelektronmikroskop. Experiment utfördes också i industrimiljö.

    Experimenten visade att kärnbildningstemperaturen steg för primära α-Fe intermetaller med ökade andelar av Fe, Mn och Cr. Resultaten tyder starkt på att primär α-Fe kärnbildas på oxider och att de växer i fyra olika morfologier. Lägre kärnbildningstäthet av α-Fe främjade snabbare tillväxt av kristaller med håligheter men högre kärnbildningstäthet främjade långsammare tillväxt av massiva kristaller. Resultaten visade också att minskad storlek av eutektiskt Si och β-Fe intermetaller ledde till förbättring av dragprovsresultaten, främst brottförlängningen. I legeringar med β-Fe ledde transversellt orienterade intermetaller till makrosprickor vilka kan initiera brott. I legeringar med primär α-Fe var det främst kluster av intermetaller som orsakade makrosprickor. I utmattningsprovning orsakade modifiering av β-Fe till α-Fe förflyttning av sprickinitieringen från oxider och porer till α-Fe, vilket resulterade i en reducerad utmattningshållfasthet. Oxiderna i Al-Si-legeringar fortsätter att gäcka; ingen korrelation mellan försök att kvantifiera oxiderna och draghållfasthet kunde påvisas.

  • 23.
    Bjurenstedt, Anton
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Casari, Daniele
    Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Mathiesen, Ragnvald H.
    Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway.
    Dahle, Arne K.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    In-situ study of morphology and growth of primary α-Al(FeMnCr)Si intermetallics in an Al-Si alloy2017Ingår i: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 130, s. 1-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Morphology and growth of primary α-Al(FeMnCr)Si intermetallics have been studied in-situ during solidification of a commercial secondary aluminum alloy employing X-radiographic imaging combined with deep-etching. The α-Al(FeMnCr)Si intermetallics were found to nucleate primarily on surface oxides, and the continued growth yielded both rhombic dodecahedrons and elongated rod-like morphologies. Both morphologies were observed as hopper and massive types, where the hopper intermetallics had the higher growth rates. The growth rate, which determines the type, appears to be linked to nucleation frequency; higher nucleation frequency promoted massive types and lower nucleation frequency promoted hopper intermetallics. 

  • 24.
    Bjurenstedt, Anton
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Ghassemali, Ehsan
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. 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.
    Dahle, Arne
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    The effect of Fe-rich intermetallics on crack initiation in cast aluminium: an in-situ tensile study2019Ingår i: Materials Science & Engineering: A, ISSN 0921-5093, E-ISSN 1873-4936, Vol. 756, s. 502-507Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To evaluate the role of Fe-rich intermetallics on crack initiation, two fully modified Al-Si alloys, one containing plate-like β-Fe and the second containing primary α-Fe intermetallics, were investigated by in-situ tensile testing in the scanning electron microscope. In the first alloy, large plate-like β-Fe intermetallics oriented parallel to the test direction were the first to crack at an elongation of about 1.8%. More transversely oriented intermetallics caused crack initiation in the matrix which linked up with the final fracture. In the second alloy, the cracking of α-Fe intermetallics initiated at an elongation of about 0.9%. It is concluded that large α-Fe intermetallics crack first and that clusters of α-Fe are the most potent crack initiation sites.

  • 25.
    Bogdanoff, Toni
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Development of aluminium-silicon alloys with improved properties at elevated temperature2017Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Aluminium-silicon alloys have gained increasing market share in the automotive and aerospace industry because of increased environmental demands. These alloys have a high strength-to-weight ratio, good corrosion resistance, castability and recycling potential. However, variations in properties and limited performance at elevated temperature are restricting these alloys from use at elevated temperatures. During the last decades, researchers have investigated ways to improve the properties at elevated temperatures. However, the effect of some transition elements is not well understood. The aim of this work is to investigate the aluminium-silicon alloys with addition of cobalt and nickel for high temperature applications. Tensile testing and hardness testing were conducted on samples produced by directional solidification in a Bridgman furnace with condition generating a microstructure corresponding to that obtained in high pressure die casting, i.e. SDAS ~ 10 µm. The results show that cobalt and nickel improve the tensile properties up to 230 °C.

  • 26.
    Bogdanoff, Toni
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Dahle, Arne K.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Effect of Co and Ni Addition on the Microstructure and Mechanical Properties at Room and Elevated Temperature of an Al–7%Si Alloy2018Ingår i: International Journal of metalcasting, ISSN 1939-5981, E-ISSN 2163-3193, Vol. 12, nr 3, s. 434-440Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Increasing environmental demands are forcing the automotive industry to reduce vehicle emissions by producing more light-weight and fuel efficient vehicles. Al–Si alloys are commonly used in automotive applications because of excellent castability, high thermal conductivity, good wear properties and high strength-to-weight ratio. However, most of the aluminium alloys on the market exhibit significantly reduced strength at temperatures above 200 °C. This paper presents results of a study of the effects of Co and Ni in a hypoeutectic Al–Si alloy on microstructure and mechanical properties at room and elevated temperature. Tensile test specimens with microstructures comparable to those obtained in high-pressure die casting, i.e. SDAS ~ 10 µm, were produced by directional solidification in a Bridgman furnace. The results show an improvement in tensile properties up to 230 °C.

  • 27.
    Bogdanoff, Toni
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Ghassemali, Ehsan
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Riestra, Martin
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Prototyping of a high pressure die cast al-si alloy using plaster mold casting to replicate corresponding mechanical properties2019Ingår i: Minerals, Metals and Materials Series, Springer, 2019, s. 435-442Konferensbidrag (Refereegranskat)
    Abstract [en]

    Prototyping prior high pressure die casting (HPDC) is used for product/mold design optimization. Plaster mold casting is a cost-efficient prototyping technique providing good surface quality and dimension accuracy, similar to HPDC components. However, the corresponding mechanical properties of a component produced with these two methods are diverging significantly, mainly due to differences in the cooling rate. This work presents a procedure to optimize the plaster mold casting for prototyping to replicate mechanical properties of a commonly used Al-Si alloy (A380). Two commercial alloys with compositions close to the A380 alloy (A356.0 and A360.2) were used. Yield strength was considered as the main design criteria, thus the target mechanical property. Tensile testing results showed that with an optimized T6 heat treatment, not only the yield strength, but also ultimate tensile strength and elongation correspond well to the properties in the HPDC component.

  • 28.
    Bogdanoff, Toni
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    Dahle, Arne K.
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning.
    The effect of SI content on microstructure and mechanical properties of Al-Si alloy2016Ingår i: La Metallurgia Italiana, ISSN 0026-0843, Vol. 108, nr 6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Al-Si alloys are the most popular casting alloys due to their excellent castability combined with high strengthto-weight ratio. This paper investigates the role of Si content in the range of 6.5 wt. % to 14.4 wt. % on the microstructure and mechanical properties of Al-Si-Mg casting alloys. All alloys were modified with 90-150 ppm Sr. No grain refiner was added. The samples were produced by directional solidification providing a microstructure that corresponds to microstructures found in die castings. From the phase diagram and coupled zone, increasing the Si level up to 14.4 wt. % is expected to start a competition between formation of α- dendrites and a fully eutectic microstructure. However, it is known that Sr-modification shifts the eutectic to higher Si contents. For the lower Si contents, the microstructure of the samples consisted of α-dendrites and a modified Al-Si eutectic. At 12.4 wt. % Si and above, a cellular eutectic microstructure was observed. No primary Si was observed even at 14.4 wt. % Si. The mechanical properties in terms of yield and tensile strength did not vary remarkably as a function of the Si level unlike the elongation to failure that dropped from 12 % at 6.5 wt. % Si to nearly 6 % at 14.4 wt. % Si; but still the material is exhibiting an elongation to failure that is far higher than normally expected.

  • 29.
    Borkar, Hemant
    et al.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning. Discipline of Metallurgy Engineering and Materials Science, Indian Institute of Technology Indore, India.
    Seifeddine, Salem
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Jarfors, Anders E.W.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Microstructure, texture and mechanical properties of al alloy a380 prepared by directional solidification method2019Ingår i: Manufacturing Sciences and Technologies IX: 9th International Conference on Manufacturing Science and Technology (ICMST 2018), Trans Tech Publications, 2019, Vol. 287, s. 18-23Konferensbidrag (Refereegranskat)
    Abstract [en]

    The mechanical properties of Al-Si alloys are affected by several microstructural features such as secondary dendrite arm spacing (SDAS), size and shape of eutectic Si-particles, presence of intermetallics as well as by porosity. In the current study, Al-Si-Cu alloy A380 was prepared by a unique directional solidification method to produce samples with two different SDAS of 9 μm and 27 μm. The lower solidification rate resulted in larger SDAS, larger grain size, larger eutectic Si and larger intermetallics including Fe-rich β phase. The microstructure with higher solidification rate was found to be finer and more homogeneous with smaller eutectic Si and intermetallics. The specimen with larger SDAS exhibited stronger texture than the one with smaller SDAS. The specimen with smaller SDAS showed improved mechanical properties including YS, UTS and ductility. 

  • 30.
    Burman, E.
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, M. G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Massing, A.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    A stable cut finite element method for partial differential equations on surfaces: The Helmholtz–Beltrami operator2020Ingår i: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 362, artikel-id 112803Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider solving the surface Helmholtz equation on a smooth two dimensional surface embedded into a three dimensional space meshed with tetrahedra. The mesh does not respect the surface and thus the surface cuts through the elements. We consider a Galerkin method based on using the restrictions of continuous piecewise linears defined on the tetrahedra to the surface as trial and test functions. Using a stabilized method combining Galerkin least squares stabilization and a penalty on the gradient jumps we obtain stability of the discrete formulation under the condition hk<C, where h denotes the mesh size, k the wave number and C a constant depending mainly on the surface curvature κ, but not on the surface/mesh intersection. Optimal error estimates in the H1 and L2-norms follow.

  • 31.
    Burman, Erik
    et al.
    University College London, London, United Kingdom.
    Elfverson, Daniel
    Umeå University, Umeå, Sweden.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Umeå University, Umeå, Sweden.
    Larsson, Karl
    Umeå University, Umeå, Sweden.
    Cut topology optimization for linear elasticity with coupling to parametric nondesign domain regions2019Ingår i: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 350, s. 462-479Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a density based topology optimization method for linear elasticity based on the cut finite element method. More precisely, the design domain is discretized using cut finite elements which allow complicated geometry to be represented on a structured fixed background mesh. The geometry of the design domain is allowed to cut through the background mesh in an arbitrary way and certain stabilization terms are added in the vicinity of the cut boundary, which guarantee stability of the method. Furthermore, in addition to standard Dirichlet and Neumann conditions we consider interface conditions enabling coupling of the design domain to parts of the structure for which the design is already given. These given parts of the structure, called the nondesign domain regions, typically represent parts of the geometry provided by the designer. The nondesign domain regions may be discretized independently from the design domains using for example parametric meshed finite elements or isogeometric analysis. The interface and Dirichlet conditions are based on Nitsche's method and are stable for the full range of density parameters. In particular we obtain a traction-free Neumann condition in the limit when the density tends to zero. 

  • 32.
    Burman, Erik
    et al.
    University College London, UK, Department of Mathematics.
    Elfverson, Daniel
    Umeå universitet, Institutionen för matematik och matematisk statistik.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Umeå universitet, Institutionen för matematik och matematisk statistik.
    Larsson, Karl
    Umeå universitet, Institutionen för matematik och matematisk statistik.
    Hybridized CutFEM for Elliptic Interface Problems2019Ingår i: SIAM Journal on Scientific Computing, ISSN 1064-8275, E-ISSN 1095-7197, Vol. 41, nr 5, s. A3354-A3380Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We design and analyze a hybridized cut finite element method for elliptic interface problems. In this method very general meshes can be coupled over internal unfitted interfaces, through a skeletal variable, using a Nitsche type approach. We discuss how optimal error estimates for the method are obtained using the tools of cut finite element methods and prove a condition number estimate for the Schur complement. Finally, we present illustrating numerical examples.

  • 33.
    Burman, Erik
    et al.
    University College London, United Kingdom.
    Elfverson, Daniel
    Umeå universitet, Sweden.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats
    Umeå universitet, Sweden.
    Larsson, Karl
    Umeå universitet, Sweden.
    Shape optimization using the cut finite element method2018Ingår i: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 328, s. 242-261Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a cut finite element method for shape optimization in the case of linear elasticity. The elastic domain is defined by a level-set function, and the evolution of the domain is obtained by moving the level-set along a velocity field using a transport equation. The velocity field is the largest decreasing direction of the shape derivative that satisfies a certain regularity requirement and the computation of the shape derivative is based on a volume formulation. Using the cut finite element method no re-meshing is required when updating the domain and we may also use higher order finite element approximations. To obtain a stable method, stabilization terms are added in the vicinity of the cut elements at the boundary, which provides control of the variation of the solution in the vicinity of the boundary. We implement and illustrate the performance of the method in the two-dimensional case, considering both triangular and quadrilateral meshes as well as finite element spaces of different order.

  • 34.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Stabilized nonconforming finite element methods for data assimilation in incompressible flows2018Ingår i: Mathematics of Computation, ISSN 0025-5718, E-ISSN 1088-6842, Vol. 87, nr 311, s. 1029-1050Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider a stabilized nonconforming finite element method for data assimilation in incompressible flow subject to the Stokes equations. The method uses a primal dual structure that allows for the inclusion of nonstandard data. Error estimates are obtained that are optimal compared to the conditional stability of the ill-posed data assimilation problem.

  • 35.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    A cut finite element method with boundary value correction2018Ingår i: Mathematics of Computation, ISSN 0025-5718, E-ISSN 1088-6842, Vol. 87, nr 310, s. 633-657Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this contribution we develop a cut finite element method with boundary value correction of the type originally proposed by Bramble, Dupont, and Thomée in [Math. Comp. 26 (1972), 869-879]. The cut finite element method is a fictitious domain method with Nitsche-type enforcement of Dirichlet conditions together with stabilization of the elements at the boundary which is stable and enjoy optimal order approximation properties. A computational difficulty is, however, the geometric computations related to quadrature on the cut elements which must be accurate enough to achieve higher order approximation. With boundary value correction we may use only a piecewise linear approximation of the boundary, which is very convenient in a cut finite element method, and still obtain optimal order convergence. The boundary value correction is a modified Nitsche formulation involving a Taylor expansion in the normal direction compensating for the approximation of the boundary. Key to the analysis is a consistent stabilization term which enables us to prove stability of the method and a priori error estimates with explicit dependence on the meshsize and distance between the exact and approximate boundary.

  • 36.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    A simple approach for finite element simulation of reinforced plates2018Ingår i: Finite elements in analysis and design (Print), ISSN 0168-874X, E-ISSN 1872-6925, Vol. 142, s. 51-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a new approach for adding Bernoulli beam reinforcements to Kirchhoff plates. The plate is discretised using a continuous/discontinuous finite element method based on standard continuous piecewise polynomial finite element spaces. The beams are discretised by the CutFEM technique of letting the basis functions of the plate represent also the beams which are allowed to pass through the plate elements. This allows for a fast and easy way of assessing where the plate should be supported, for instance, in an optimization loop.

  • 37.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    A simple finite element method for elliptic bulk problems with embedded surfaces2019Ingår i: Computational Geosciences, ISSN 1420-0597, E-ISSN 1573-1499, Vol. 23, nr 1, s. 189-199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we develop a simple finite element method for simulation of embedded layers of high permeability in a matrix of lower permeability using a basic model of Darcy flow in embedded cracks. The cracks are allowed to cut through the mesh in arbitrary fashion and we take the flow in the crack into account by superposition. The fact that we use continuous elements leads to suboptimal convergence due to the loss of regularity across the crack. We therefore refine the mesh in the vicinity of the crack in order to recover optimal order convergence in terms of the global mesh parameter. The proper degree of refinement is determined based on an a priori error estimate and can thus be performed before the actual finite element computation is started. Numerical examples showing this effect and confirming the theoretical results are provided. The approach is easy to implement and beneficial for rapid assessment of the effect of crack orientation and may for example be used in an optimization loop. 

  • 38.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Augmented Lagrangian and Galerkin least-squares methods for membrane contact2018Ingår i: International Journal for Numerical Methods in Engineering, ISSN 0029-5981, E-ISSN 1097-0207, Vol. 114, nr 11, s. 1179-1191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we propose a stabilized finite element method for the numerical solution of contact between a small deformation elastic membrane and a rigid obstacle. We limit ourselves to friction-free contact, but the formulation is readily extendable to more complex situations. 

  • 39.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Augmented Lagrangian finite element methods for contact problems2019Ingår i: Mathematical Modelling and Numerical Analysis, ISSN 0764-583X, E-ISSN 1290-3841, Vol. 53, nr 1, s. 173-195Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose two different Lagrange multiplier methods for contact problems derived from the augmented Lagrangian variational formulation. Both the obstacle problem, where a constraint on the solution is imposed in the bulk domain and the Signorini problem, where a lateral contact condition is imposed are considered. We consider both continuous and discontinuous approximation spaces for the Lagrange multiplier. In the latter case the method is unstable and a penalty on the jump of the multiplier must be applied for stability. We prove the existence and uniqueness of discrete solutions, best approximation estimates and convergence estimates that are optimal compared to the regularity of the solution. 

  • 40.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Dirichlet boundary value correction using Lagrange multipliers2019Ingår i: BIT Numerical Mathematics, ISSN 0006-3835, E-ISSN 1572-9125Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose a boundary value correction approach for cases when curved boundaries are approximated by straight lines (planes) and Lagrange multipliers are used to enforce Dirichlet boundary conditions. The approach allows for optimal order convergence for polynomial order up to 3. We show the relation to a Taylor series expansion approach previously used in the context of Nitsche’s method and, in the case of inf-sup stable multiplier methods, prove a priori error estimates with explicit dependence on the meshsize and distance between the exact and approximate boundary. 

  • 41.
    Burman, Erik
    et al.
    University College London, London, UK.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G
    Umeå University, Umeå, Sweden.
    Solving ill-posed control problems by stabilized finite element methods: an alternative to Tikhonov regularization2018Ingår i: Inverse Problems, ISSN 0266-5611, E-ISSN 1361-6420, Vol. 34, nr 3, artikel-id 035004Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tikhonov regularization is one of the most commonly used methods for the regularization of ill-posed problems. In the setting of finite element solutions of elliptic partial differential control problems, Tikhonov regularization amounts to adding suitably weighted least squares terms of the control variable, or derivatives thereof, to the Lagrangian determining the optimality system. In this note we show that the stabilization methods for discretely illposed problems developed in the setting of convection-dominated convection– diffusion problems, can be highly suitable for stabilizing optimal control problems, and that Tikhonov regularization will lead to less accurate discrete solutions. We consider some inverse problems for Poisson’s equation as an illustration and derive new error estimates both for the reconstruction of the solution from the measured data and reconstruction of the source term from the measured data. These estimates include both the effect of the discretization error and error in the measurements.

  • 42.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Larsson, Karl
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Cut finite elements for convection in fractured domains2019Ingår i: Computers & Fluids, ISSN 0045-7930, E-ISSN 1879-0747, Vol. 179, s. 728-736Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a cut finite element method (CutFEM) for the convection problem in a so called fractured domain, which is a union of manifolds of different dimensions such that a d dimensional component always resides on the boundary of a d+1 dimensional component. This type of domain can for instance be used to model porous media with embedded fractures that may intersect. The convection problem is formulated in a compact form suitable for analysis using natural abstract directional derivative and divergence operators. The cut finite element method is posed on a fixed background mesh that covers the domain and the manifolds are allowed to cut through a fixed background mesh in an arbitrary way. We consider a simple method based on continuous piecewise linear elements together with weak enforcement of the coupling conditions and stabilization. We prove a priori error estimates and present illustrating numerical examples.

  • 43.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Larsson, Karl
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Massing, André
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Finite element approximation of the Laplace–Beltrami operator on a surface with boundary2019Ingår i: Numerische Mathematik, ISSN 0029-599X, E-ISSN 0945-3245, Vol. 141, nr 1, s. 141-172Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a finite element method for the Laplace–Beltrami operator on a surface with boundary and nonhomogeneous Dirichlet boundary conditions. The method is based on a triangulation of the surface and the boundary conditions are enforced weakly using Nitsche’s method. We prove optimal order a priori error estimates for piecewise continuous polynomials of order (Formula presented.) in the energy and (Formula presented.) norms that take the approximation of the surface and the boundary into account. 

  • 44.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Massing, André
    Department of Mathematics and Mathematical Statistics, Umeå University, Sweden.
    Cut finite element methods for partial differential equations on embedded manifolds of arbitrary codimensions2019Ingår i: Mathematical Modelling and Numerical Analysis, ISSN 0764-583X, E-ISSN 1290-3841, Vol. 52, nr 6, s. 2247-2282Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a theoretical framework for the analysis of stabilized cut finite element methods for the Laplace-Beltrami operator on a manifold embedded in Rd of arbitrary codimension. The method is based on using continuous piecewise linears on a background mesh in the embedding space for approximation together with a stabilizing form that ensures that the resulting problem is stable. The discrete manifold is represented using a triangulation which does not match the background mesh and does not need to be shape-regular, which includes level set descriptions of codimension one manifolds and the non-matching embedding of independently triangulated manifolds as special cases. We identify abstract key assumptions on the stabilizing form which allow us to prove a bound on the condition number of the stiffness matrix and optimal order a priori estimates. The key assumptions are verified for three different realizations of the stabilizing form including a novel stabilization approach based on penalizing the surface normal gradient on the background mesh. Finally, we present numerical results illustrating our results for a curve and a surface embedded in R3.

  • 45.
    Burman, Erik
    et al.
    Department of Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Massing, André
    Department of Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Zahedi, Sara
    Department of Mathematics, KTH Royal Institute of Technology, Stockholm, Sweden.
    A stabilized cut streamline diffusion finite element method for convection–diffusion problems on surfaces2020Ingår i: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 358, artikel-id 112645Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a stabilized cut finite element method for the stationary convection–diffusion problem on a surface embedded in Rd. The cut finite element method is based on using an embedding of the surface into a three dimensional mesh consisting of tetrahedra and then using the restriction of the standard piecewise linear continuous elements to a piecewise linear approximation of the surface. The stabilization consists of a standard streamline diffusion stabilization term on the discrete surface and a so called normal gradient stabilization term on the full tetrahedral elements in the active mesh. We prove optimal order a priori error estimates in the standard norm associated with the streamline diffusion method and bounds for the condition number of the resulting stiffness matrix. The condition number is of optimal order for a specific choice of method parameters. Numerical examples supporting our theoretical results are also included. 

  • 46.
    Burman, Erik
    et al.
    Mathematics, University College London, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Mathematics and Mathematical Statistics, Umeå University, Umeå, Sweden.
    Samvin, David
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    A cut finite element method for elliptic bulk problems with embedded surfaces2019Ingår i: GEM - International Journal on Geomathematics, ISSN 1869-2672, E-ISSN 1869-2680, Vol. 10, nr 1, artikel-id 10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose an unfitted finite element method for flow in fractured porous media. The coupling across the fracture uses a Nitsche type mortaring, allowing for an accurate representation of the jump in the normal component of the gradient of the discrete solution across the fracture. The flow field in the fracture is modelled simultaneously, using the average of traces of the bulk variables on the fractures. In particular the Laplace–Beltrami operator for the transport in the fracture is included using the average of the projection on the tangential plane of the fracture of the trace of the bulk gradient. Optimal order error estimates are proven under suitable regularity assumptions on the domain geometry. The extension to the case of bifurcating fractures is discussed. Finally the theory is illustrated by a series of numerical examples. 

  • 47.
    Burman, Erik
    et al.
    UCL, Department of Mathematics, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Umeå Universitet, Department of Mathematics and Mathematical Statistics, Umeå, Sweden.
    Zahedi, Sara
    The Royal Institute of Technology (KTH), Department of Mathematics, Stockholm, Sweden.
    Stabilized CutFEM for the convection problem on surfaces2019Ingår i: Numerische Mathematik, ISSN 0029-599X, E-ISSN 0945-3245, Vol. 141, nr 1, s. 103-139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We develop a stabilized cut finite element method for the convection problem on a surface based on continuous piecewise linear approximation and gradient jump stabilization terms. The discrete piecewise linear surface cuts through a background mesh consisting of tetrahedra in an arbitrary way and the finite element space consists of piecewise linear continuous functions defined on the background mesh. The variational form involves integrals on the surface and the gradient jump stabilization term is defined on the full faces of the tetrahedra. The stabilization term serves two purposes: first the method is stabilized and secondly the resulting linear system of equations is algebraically stable. We establish stability results that are analogous to the standard meshed flat case and prove h3 / 2 order convergence in the natural norm associated with the method and that the full gradient enjoys h3 / 4 order of convergence in L2. We also show that the condition number of the stiffness matrix is bounded by h- 2. Finally, our results are verified by numerical examples. 

  • 48.
    Burman, Erik N.
    et al.
    UCL, Department of Mathematics, London, United Kingdom.
    Hansbo, Peter
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Larson, Mats G.
    Umeå Universitet, Department of Mathematics and Mathematical Statistics, Umeå, Sweden.
    A cut finite element method with boundary value correction for the incompressible Stokes equations2019Ingår i: Numerical mathematics and advanced applications ENUMATH 2017, Cham: Springer, 2019, Vol. 126, s. 183-192Konferensbidrag (Refereegranskat)
    Abstract [en]

    We design a cut finite element method for the incompressible Stokes equations on domains with curved boundary. The cut finite element method allows for the domain boundary to cut through the elements of the computational mesh in a very general fashion. To further facilitate the implementation we propose to use a piecewise affine discrete domain even if the physical domain has curved boundary. Dirichlet boundary conditions are imposed using Nitsche’s method on the discrete boundary and the effect of the curved physical boundary is accounted for using the boundary value correction technique introduced for cut finite element methods in Burman et al. (Math Comput 87(310):633–657, 2018). 

  • 49. Campbell, John
    et al.
    Svidró, József Tamás
    Högskolan i Jönköping, Tekniska Högskolan, JTH. Forskningsmiljö Material och tillverkning – Gjutning. Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Svidró, Judit
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Molding and Casting Processes2017Ingår i: ASM Handbook, Volume 1A: Cast Iron Science and Technology / [ed] Doru M. Stefanescu, Materials Park, Ohio: ASM International, 2017, s. 189-206Kapitel i bok, del av antologi (Refereegranskat)
  • 50.
    Ceschini, Lorella
    et al.
    Department of Industrial Engineering (DIN), Alma Mater Studiorum–University of Bologna, Bologna, Italy.
    Dahle, Arne
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Gupta, Manoj
    Department of Mechanical Engineering, National University of Singapore, Singapore.
    Jarfors, Anders E.W.
    Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning.
    Jayalakshmi, S.
    Department of Mechanical Engineering, Bannari Amman Institute of Technology (BIT), Sathyamangalam, India.
    Morri, Alessandro
    Interdepartmental Center for Industrial Research-Advanced Mechanics and Materials (CIRI-MAM), Alma Mater Studiorum–University of Bologna, Bologna, Italy.
    Rotundo, Fabio
    Interdepartmental Center for Industrial Research-Advanced Mechanics and Materials (CIRI-MAM), Alma Mater Studiorum–University of Bologna, Bologna, Italy.
    Toschi, Stefania
    Department of Industrial Engineering (DIN), Alma Mater Studiorum–University of Bologna, Bologna, Italy.
    Singh, R. Arvind
    Department of Aeronautical Engineering, Bannari Amman Institute of Technology (BIT), Sathyamangalam, India.
    Aluminum and Magnesium Metal Matrix Nanocomposites2017Bok (Övrigt vetenskapligt)
    Abstract [en]

    The book looks into the recent advances in the ex-situ production routes and properties of aluminum and magnesium based metal matrix nanocomposites (MMNCs), produced either by liquid or semi-solid state methods. It comprehensively summarizes work done in the last 10 years including the mechanical properties of different matrix/nanoreinforcement systems. The book also addresses future research direction, steps taken and missing developments to achieve the full industrial exploitation of such composites. The content of the book appeals to researchers and industrial practitioners in the area of materials development for metal matrix nanocomposites and its applications.

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