On the Possibility to Increase Maximum Operating Temperature (MOT) of Al 20%SiC Composites for Mechanical Properties
2020 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Student thesis
Abstract [en]
The main objective of this project is to seek the possibility to increase the maximum temperature, to improve mechanical properties and also analyse the microstructure of Al-20%SiC composite by manipulating its transition metals using four different additions of Zr, Ni, Si, Ti, Mg, Mn, Cr, Fe and Cu and conduct tensile and compression test to find out the mechanical properties of the composite of Brake Discs at ambient and elevated temperatures as company’s requirements(AC Floby) the casting will be done using vertical high pressure die casting process at Jönköping University which is collaborated with AC Floby for the materials and machining. The tensile and compression tests were conducted at Jönköping University in accordance to standard ASTM B557M for standard tension test of metals at room temperature and ASTM E21 for the tensile test of metal at elevated temperature, ASTM E9 for compression test.
The scope of this project is to obtain stronger brake discs that can withstand high temperature and loads, to reduce vehicle’s weight and emissions by using the Al-20%SiC alloy since it has low density, high thermal conductivity, good corrosion resistance, strength and wear property.
This project is part of a large project which was done by the next group that handles with the possibility to increase the maximum operating temperature of Al-20%SiC alloys to obtain wear friction and thermal physical properties. Hence, this gives the opportunity to understand the mechanical properties and thermal physical properties of the same newly developed Al-20%SiC alloys that is shared with the other group to validate the outcome of compositions of alloy 1 and alloy2 used in the project and compare between the two alloys. The operating temperature will rise, and the alloy strength falls due to elevated temperature and other microstructure defects hence our aim is to make the properties of alloy sustain at elevated temperature and reduce coarsening and wear in Brake Discs. Hence, we initiated by narrowing down the additions into the metal matrix Aluminium by using Thermo calc software to study the effect of each element on the Aluminium and the binary phase diagram of each alloying element in aluminium primary matrix. And to determine the effect of reinforcing SiC particles that provides strength, tensile and compressive properties at elevated temperature and came up with the satisfying additions for the alloy which will be explained further below in the report. A validation of the alloy was carried out against the tensile and compression experimental results to evaluate the predictive and better properties of the newly developed alloy for brake discs by comparing with the alloy 1 and alloy 2 compositions.
Place, publisher, year, edition, pages
2020. , p. 65
Keywords [en]
Zirconium, Nickel, Titanium, Copper, Chromium, Iron, Magnesium, Manganese and Silicon, Tensile and compression tests, friction co-efficient, thermal coefficient of expansion, sludge factor, stress-strain diagram, SEM, eutectic particles, grain structure, vertical high pressure die casting, eutectic solidification, Hall Petch equation and Hollomon’s equation.
National Category
Composite Science and Engineering
Identifiers
URN: urn:nbn:se:hj:diva-47726ISRN: JU-JTH-PRU-2-20200181OAI: oai:DiVA.org:hj-47726DiVA, id: diva2:1391324
External cooperation
AC Floby
Subject / course
JTH, Product Development
Supervisors
Examiners
2020-02-042020-02-042020-02-04Bibliographically approved