Hot workability and processing maps of aluminium based discontinuously reinforced composites

Hot deformation behaviour under tensile conditions of Al6061/20%Al2O3, Al2618/20%,Al2O3, and Al2618/20%SiC particle reinforced composites and of an unreinforced 6061 aluminium alloy was investigated in the temperature range 350 - 500degreesC and in the strain rate range 10(-3) - 10(-1) s(-1). Processing maps were generated from the obtained data and the domains of optimal hot workability were identified for the different materials. Microstructural analyses on deformed specimens allowed it to be stated that dynamic recovery was the main restoration mechanism for the composites investigated. The concurrent evaluation of ductility and flow stress data also suggested that differences in reinforcement properties can play a significant role on property definition. (C) 2002 IoM Communications Ltd.