Optimization of wear parameters of a Hybrid MMC using Design of Experiments

Abstract

Aluminum metal matrix composites (MMC) are finding broad applications in aerospace, automobile and general engineering industries owing to their improved mechanical and wear behavior. Aluminium alloy Al-6Mg, graphite and flyash composites were obtained by stir casting technique. Four different weight percent (2, 4, 6& 8) of particulate reinforcement materials were added to the base alloy. The wear tests were conducted with a constant track radius of 50mm, constant speed of 500rpm, Loads varying from 10N to 40N, sliding distance varying from 0.5km to 2Km.The matrix alloy undergoes severe specific wear rate beyond 1.5 Km of sliding distance migrating toward seizure with the applied load beyond 20N. However, the MMCs maintains almost a linear trend with the sliding distance up to 2000 m with the applied load of 10 N. Similar trend is noticed for all the samples of MMCs even with applied loads of 30 N to 40 N with a little deviation in some of the composite specimens. The optimum values are Load=30N, 2% flyash and 6% graphite and 1.5 Km sliding distance. From the analysis of variance & S/N ratio, it is inferred that the sliding distance has the highest contribution on wear rate followed by load & reinforcement percentage.