Optimization of powder metallurgy parameters to obtain low corrosion rate and high compressive strength in Al-MoO3 composites using SN ratio and ANOVA analysis

Abstract

The powder metallurgy technique is considered and proved to be one of the successful fabrication methods in fabricating metal matrix composites. In this work aluminium matrix was reinforced with 5, 10, 15 wt% MoO3 through powder metallurgy route. The objective of this paper is to optimize the powder metallurgy process parameters to obtain low corrosion rate, high compressive strength and high compressive strain percentage. The significance and the effect of process parameters on corrosion rate, compressive strength and compressive strain percentage was studied. Taguchi method and ANOVA were employed to perform optimization and the run order to conduct experiments was chosen using L9 orthogonal array. Through analysis of the experimental data, the reinforcement weight percentage was identified to be the most influencing factor for attaining maximum compressive strength and compressive strain percentage and sintering temperature plays vital role in corrosion rate. The optimum condition to obtain low corrosion rate is 5 wt% MoO3, 300 MPa compaction pressure, 400 °C sintering temperature, high compressive strength is 15 wt% MoO3, 300 MPa compaction pressure, 400 °C sintering temperature, and for high compressive strain percentage is 5 wt% MoO3 , 250 MPa compaction pressure, 400 °C sintering temperature. The uniform distribution of reinforcement over the matrix and the absence of clusters and agglomeration of reinforcement particles were confirmed through SEM test.