A combined approach to grey relational analysis and principal component analysis for development of input parameters in the wear characterization of Al7075 (SiC+Al2O3) hybrid metal matrix composites

The mechanical stir casting effect on Al7075 based lightweight alloy established with Al2O3 and SiC has been studied with varied stirrer time and speed. Hybrid metal matrix improved wear resistance of composite material Al7075 (SiC+Al2O3). Experimental designs are formulated using Taguchi’s DoE. Considered 4 level 4 parameters, L16 OA is selected. Grey Relational Analysis (GRA) and Principle component analysis (PCA) coupled has been employed to calculate matrix composition. POD test (Pin-on-Disc) was used to measure the wear resistance of the casted pins. Further, mechanical characterization tests like tensile, hardness, impact, density and porosity were also accomplished. Optimum parameters are found, SiC of 6%, Al2O3 of 4%, Stirrer time of 15 min and stirrer speed of 600rpm, which gives low wear loss of 0.0034g, superior micro hardness 154.22 BHN, the tensile strength of 443.61 Mpa and Impact energy is 3J. From the ANOVA results, Stirrer speed is the most influential parameter with 49.40%. SEM-EDX analysis characterized the worn surfaces.