Tribological analysis of Al-Si alloy based MMCs at elevated temperature

Abstract

In the current study, investigates the tribological behaviour of aluminium-based metal matrix composites (MMCs) and aluminium-based hybrid metal matrix composites (HMMCs) fabricated through the stir casting process. Reinforcements like Al2O3 and SiC are vastly used to enhance the quality of metal facets and reduce the rate of wear. In this work, the matrix metal Al alloy (LM6) is reinforced with 10 wt% of (Al2O3), 10 wt% of (SiC) & (5%SiC + 5%Al2O3) to manufacture MMCs & HMMCs respectively, and 1 wt% of Mg mainly used for wettability of composites. The whole tribological experiment carried out through a computerized pin-on-disc setup by varying the input parameters like elevated temperature (T) i.e. 50,100,150 °C, sliding distance (D) i.e. 500, 1000, 1500 m, and sliding velocity (V) i.e. 1,2,3 m/s with a constant load of 24.5 N. The outcome response is considered as wear rate (WR) (mm3/m) and coefficient of friction (COF). The observations are designed based on one of the robust methods i.e. taguchi (L9) orthogonal array. Analysis of variance(ANOVA) revealed that both elevated temperature and sliding distance are the most regulating factors compared to sliding velocity. All the observations are conducted at a persistent load of 24.5 N and ANOVA revealed that elevated temperature is an outrageous regulating factor followed by sliding distance, sliding velocity. Elevated temperature is the most influencing factor in HMMCs (Al2O3 & SiC) whereas both sliding distance and elevated temperature are the regulating factor for MMCs (Al2O3/SiC). Finally, worn-out areas of specimens were analysed through scanning electron microscope (SEM) and Regression equations value by a confirmation test.