Age-Hardening Responses of Al–Cu Alloy Powders Processed by Equal Channel Angular Pressing

Mixed powders of Al plus 4 wt % Cu were processed compacting by two different methods which were i) equal channel angular pressing (ECAP) and ii) conventional powder metallurgy (P/M). All specimens were sintered at 600°C for 2 hours under inert argon (Ar) gas atmosphere. These sintered materials were solution treated for 4 and 8 hours at 550°C and then they were quenched to room temperature. After that, all of them were age hardened at particular time periods up to 10 hours at 190°C. Microhardness, microstructures (SEM-EDS analysis) and relative densities of the specimens were studied subsequent to compacting, sintering and age hardening processes respectively. Hardening improvement was achieved after ageing process in the samples produced by both processes. According to the ageing times, the highest microhardness values were obtained with ECAPed specimens which were 101 HV and 105 HV.