Effect of SiC particle size and content on strain-based pore closure rate studies on Al-SiC P/M composites during cold upsetting

A series of laboratory-scale powder metallurgical upsetting experiments was conducted during cold upsetting on sintered Al-SiC composites. Aluminium-silicon carbide composites containing 5%, 10%, 15% and 20% SiC of four different particle sizes, namely 50, 65, 120 and 180 mu m, were completely investigated. The pore closing rate and the formability strain index value were evaluated and discussed in terms of matrix and geometric work hardenings. Three novel strain-based pore closure rate indices were proposed and analysed for all the above said preforms, and their variations with respect to their relative density were plotted and discussed.