Influence of pores on workability of porous Al/SiC composites fabricated through powder metallurgy + mechanical alloying

• Compressive formability of porous Al/SiC composites fabricated MA was studied.
• Effect of milling time on different aspects of composites was studied.
• Instantaneous density coefficient and work hardening exponent decrease with increasing density.
• Strength increased with increasing milling time and amount of SiC particles and decreasing SiC size.

In the present work, the compressive formability of porous Al/SiC composites fabricated through mechanical alloying (MA) is investigated. Aluminum matrix composites consisting of pure Al reinforced with different amounts of 5, 10, 20 wt.% SiC with mean particle size of 16 μm and other composites containing 10 wt.% SiC with particle sizes of 12, 16 μm were produced by a powder metallurgy route. The effect of milling time on microstructure and mechanical properties of the composites was studied. The phased compression tests coupled with density measurement and continuous compression of the samples were indicative of increases in strength and decreases in ductility of the composites with increasing milling time, increasing amount of reinforcement particles and decreasing their size. Instantaneous density coefficient and instantaneous work hardening exponent of the samples, during deformation stages, show decreasing trends when density increased. It was also revealed that instantaneous work hardening exponent increase with increasing milling time, increasing weight percentage of the reinforcement and decreasing its particle size. The samples having higher initial densities, containing lower amounts of larger SiC particles show better workability.