Effect of Alumina on Green Properties of Al-Fe-Cr Powder Composites

Abstract

This work illustrates the results of the effect of aluminum oxide (Al2O3) on the green density, hardness and electrical conductivity of Al-Fe-Cr-Al2O3 powder composites at different compaction pressures (470 MPa, 550 MPa and 600 MPa). SEM analysis for different Al2O3 composition was done. The composite consisted of Al-75%, Fe-25%, Cr-5% by weight as matrix material and alumina (Al2O3) was added in varying percentage by weight (0-30), as reinforcement. Powders of Al, Fe, Cr and Al2O3 having average particle size of 48 µm, 150 µm, 100 µm and 100 µm respectively with all having purity ≥ 99% were used. Ethanol (5 wt. %) had been used as a process control agent (PCA). Synthesis of Al-Fe-Cr-Al2O3 composites was carried in shaker mill. The ball to powder ratio was kept 20:1. The characterization of the powder was followed by Scanning Electron Microscopy (SEM). There was an increase in green density, hardness and electrical conductivity with increase in compaction pressure but no significant effect of adding alumina on these properties was observed.