Microstructure of an Al-SiC Metal Matrix Composite

1. Collection and preparation of the raw materials to put as charge Placing raw materials in a graphite crucible under nitrogen gas into a furnace Heating the crucible above the liquidus temperature and allowing time to become completely liquid During cooling stirring is started at the semi-solid condition and continued until a temperature where less than 30% of the metal is solidified is reached 0.005m 0.065m Pouring into the mould W V Withdrawal of the composite from the mould U Desired fabricated MMCs ingots 100µm 0.105m Examination of the Semi-Solid Stir Casting Method for Producing Al-SiC Metal Matrix CompositesSumsun Naher, Dr. Dermot Brabazon and Dr. Lisa LooneyMaterials Processing Research Centre, Dublin City University, Dublin 9, Ireland Introduction: Metal matrix composites (MMCs) are a range of advanced materials that can be used for a wide range of applications within the aerospace, automotive, nuclear, biotechnology, electronic and sporting goods industries. MMCs consist of a non-metallic reinforcement incorporated into a metallic matrix which can provide advantageous properties over base metal alloys. These include improved thermal conductivity, abrasion resistance, creep resistance, dimensional stability, exceptionally good stiffness-to-weight and strength-to-weight ratios and better high temperature performance. Flow Chart for the MMC Fabrication Process Project Aims: Casting methods are considered the cheapest route to produce MMCs. Therefore, the main aim of this project is to optimise the sir casting method for an AL-SiC MMC. Computer simulation and simple experiments will examine process variables such as constituent materials, stirrer geometry and position, speed and mixture temperature. Problems in stir casting arise from particle distribution, mixing, solidification, porosity and chemical reactions. Schematic of the Compocaster set up Microstructure of an Al-SiC Metal Matrix Composite