The influence of particle sizes and compaction pressure on surface hardness of aluminum composite fabricated via powder metallurgy

Abstract

A statistical analysis was used to anticipate the influence of particles sizes and compaction pressure on surface hardness of aluminum composites after compacted in a rigid die under an uniaxial compaction. Al-20 wt.% slag powder mixtures with various particle sizes (38μm to 212μm) were prepared and their compressibility was studied in a wide range of compaction pressure up to 300 MPa. All of compacted specimens were sintered at 500°C for 2hrs. The surface hardness of each sintered specimens was measured by using Vikers Macrohardness. The outcomes of the statistical analysis are predicted by using linear or nonlinear correlation. A direct correlation between compaction pressure and surface hardness of composites was noticed. The correlation between particle sizes and surface hardness are in positive quadratic relationship. It can be concluded that the particle size and compaction pressure significantly influence the surface hardness of aluminum composite.