Grindability of Powder Compacted Al/SiCp Metal Matrix Composites

Intense reseach in material science has been directed towards the development of new light-weight engineering materials possessing high specific strength and stiffness at elevated temperatures combined with good creep, fatigue and wear resistance. Advanced automotive and aerospace technologies require such material specification for enhanced performance. These properties are not achievable with light weight monolithic titanium, aluminium and magnesium alloys. Hence designers resort to composite materials such as Fiber Reinforced Plastics (FRP), Metal Matrix Composites (MMC) and Ceramic Matrix Composites (CMC). The density of most MMC's is approximately one third that of steel, resulting in high specific strength and stiffness. MMC's find application in different industries like aerospace (for fuselage of space shuttle orbiter, vertical tail section of advanced fighter planes), automobile engine parts (piston, cylinder liners, brake drums), sports equipment and shipping application etc.,. Especially aluminium alloys reinforced with silicon carbide are relatively new, potentially useful structural materials with high specific stregth and modulus values. Although components made of these materials, can be produced by near-net-shape manufacturing, they usually require subsequent machining to attain the desired geometry, assembling tolerance and surface integrity. However, being non-hoogeneous, anisotropic and reinforced b abrasive components, these materials are difficult t achne. Machinability is one of the major problems, which restricts the wide spread engineering application of meal matrix composites. Grinding is partislarly needed to acquire controlled specifications such as high dimensional acuracy and surface finish. The presen study is concerned with evaluation of grindability of Al/SiCp composite in terms of work material and wheel material response to grinding environment. Surface grinding was carried out on a tool and cutter grinder and the performance indicators namely grinding force, temperature, acoustc emision (AE) and vibration induced were monitored online. Ground surfaces were observed through scanning electron microscope (SEM), for assessing the surface texture. samples of chips collected during grinding were observed through scannng electron microscope, for process status evaluation.