Investigation of Mechanical and Tribological Properties of Al–7 Wt.% Si alloy Metal Matrix Composites Reinforced with SiC

Abstract

Present work deals with the synthesis and characterization of Al-Si (7 wt.%) matrix composites reinforced with SiC up to 20 wt.% by the powder processing technique. Cold isostatic compaction was done by reinforcing ceramic material with silicon carbide in different proportions, i.e., x wt.% (x = 0, 5, 10, 15 and 20), sintered at different temperatures (optimized at 650 °C) in a vacuum atmosphere. The phase analysis, microstructure characterization, density measurement, flexural strength, hardness, and wear analysis were done. The X-ray Diffraction (XRD) of the composite reveals the emergence of a new phase Al4SiC4 which causes strengthening of the matrix. The Scanning Electron Microscope (SEM) shows the particle size reduced by using ball milling, which helps in densification as well as improvement of mechanical properties. Hardness increased by the addition of silicon carbide particulates in the matrix up to 280% with respect to the base matrix at 20 wt.% addition of SiC. Flexural strength increases by SiC addition in the matrix up to 170% compared to the base alloy at 15% SiC addition. The wear resistance of a 20 wt% SiC reinforced aluminium–silicon (7wt%) based alloy displayed the highest wear resistance. Due to smoother contact surfaces and thicker oxide layer formation, the average coefficient of friction value reduces significantly with the addition of SiC, as well as with greater loads. © 2023, The Author(s), under exclusive licence to Springer Nature B.V.