Influence of SiC on solid particle erosion and mechanical behaviour of Al–25Zn alloy based novel metal matrix composites fabricated through stir casting technique

Abstract

ABSTRACT This investigation studied the influence of SiC reinforcement (0, 10, 15 and 20 wt.%) on solid particle erosion and mechanical behaviour of novel Al–25Zn alloy metal matrix composites fabricated by the stir casting technique. The erosion wear experiments were conducted following the ASTM G-76 standard for various impact velocity, impingement angle, and erodent temperature as per Taguchi L16 orthogonal array using air jet erosion test rig with erodent silica sand particles of irregular shapes with size approximately 150 µm. The attempt has been made to establish linear and nonlinear correlations between input parameters and erosion rates. The artificial neural network and the Taguchi approach were used to identify the optimal parameter combination for the minimum erosion rate. The results show a significant alteration in properties with reinforcement of SiC content. The analysis of variance, signal to noise ratio, and morphology of eroded surfaces indicates that impact velocity is the most dominating parameter for the erosion rate among studied parameters. The erosion rate increased with the rise in impact velocity, whereas the highest erosion rate is observed with 30° impingement angle. For identical test conditions, optimum mechanical and erosion characteristics are noticed for the composite with 15% SiC.