Effect of Calcium Silicate on Mechanical and Frictional Wear Behaviors of AA7075 Hybrid Composites: A Statistical Analysis

Abstract

Recently, Aluminium Alloy (AA) 7075 based Metal Matrix Composites (MMC) have been widely used in aerospace applications due to their high strength to density ratio, but it mostly fails in tribo applications. The addition of ceramic material like Al2O3 to the AA7075 Hybrid Composites (AHCs) has improved their wear and thermal properties, but the density of the AHCs has also increased. In this regard, it is essential to identify a low-density ceramic to improve the wear resistance of the AHCs without affecting their density or mechanical strength. For the study on the effect of Ca2SiO4 on the AHCs, the AHCs/Al2O3/Ca2SiO4 samples were successfully fabricated and tested in terms of mechanical and frictional wear properties. The fabricated AHCs had a relative density of around 3.54±0.05% higher than AA7075, which is due to the impact of high-density ceramic Al2O3 reinforcement. The lowest specific wear rate is obtained for the AHCs/Al2O3(10 wt. %)/Ca2SiO4(8 wt. %) at the high applied load and the low sliding velocity, which is around 1.44 x 10-6 g/Nm, and its corresponding CoF is 0.158. Finally, the wear maps are developed from the contour plots of responses to identify the cause and consequences of the wear mechanism during the dry sliding of AHCs.