Modeling and analysis of the effects of age hardening, magnesium dissolution, and SiC reinforcement on wear properties in eutectic Al-Si composites using full factorial techniques

Abstract This study aims to explore the effects of age-hardened traces, magnesium (Mg) dissolution, and silicon carbide (SiC) reinforcement on the wear properties of eutectic aluminum-silicon (Al-Si) matrix composites, focusing on optimizing their performance for industrial applications. A systematic investigation was conducted using a full factorial experimental design, with analysis of variance (ANOVA) performed through Minitab software to quantify the individual and interactive effects of these factors on the wear rate and coefficient of friction (COF). The results demonstrated that age-hardened traces significantly enhance wear resistance by promoting the formation of finely dispersed hardening precipitates at moderate ageing temperatures, while over-ageing negatively impacts performance due to precipitate coarsening. SiC reinforcement emerged as a key factor in improving wear resistance, attributed to its high hardness and superior abrasion resistance. The role of Mg dissolution was found to be multifaceted, contributing to solid solution strengthening and grain refinement but also interacting with other variables in complex ways. The study concludes that the optimal combination of 1.5% Mg, 4% SiC, and a peak ageing temperature of 100 °C achieves the best balance between wear resistance and frictional performance. These findings offer valuable insights into the design of high-performance Al-Si composites, highlighting the importance of microstructural control to meet the demands of advanced engineering applications.