Consolidation of Al-5083 alloy powders by ECAP

Abstract

Mechanically alloyed Al-5083 powders with different milling times are consolidated by equal channel angular pressing (ECAP) at room temperature (RT), at high temperature (HT), up to two passes in Route A and their mechanical and physical properties are studied in this paper. Microstructural and tensile tests of RT ECAPed samples reveal weaker bonds between the particles which result in poor tensile strength and ductility. Furthermore, the fractograph of RT ECAPed samples shows that the failure is due to particle pull-out as a result of poor metallurgical bonding. Unmilled (0 h) powder is found to have achieved 99.22% of its theoretical density and 45 HRB after the first pass in HT ECAP. However, microstructural studies and tensile tests revealed good metallurgical bonds between the particles. Furthermore, the fractured surface of compacts shows that the failure surface is dominated by the ductile fracture mode. HT ECAP followed by sintering is a suitable method for achieving metallurgical bonding between microparticles.