Attainment of high specific hardness and specific modulus in spark plasma sintered aluminium‐copper‐silicon carbide‐titanium carbide hybrid composite

Abstract

AbstractAluminium matrix hybrid composites have been consolidated effectively by spark plasma sintering with new combinations of reinforcement and high volume percentage of ceramic particulates to maximize specific hardness and specific modulus through the powder metallurgy route. The aforementioned techno‐scientific accomplishment with regard to metal matrix composite aims to meet a continuous increase in the global demand for a material with minimum structural weight and high‐modulus for structural (automotive and aerospace) applications. The new aluminium based hybrid composite developed by incorporating ceramic particulate reinforcements (12.5 wt.% silicon carbide and 12.5 wt.% titanium carbide) along with 22.5 wt.% copper as the metallic reinforcement attains significantly high specific hardness (85 HV/gcm−3), specific Young's modulus (33.56 GPa/g cm−3), specific bulk modulus (27.97 GPa/g cm−3) when compared with the reported range of specific hardness (13 HV/g cm−3–89 HV/g cm−3), specific Young's modulus (24 GPa/g cm−3–27 GPa/g cm−3) and specific bulk modulus (20 GPa/g cm−3–22 GPa/g cm−3) possessed by structural steels. This is accredited to the genesis of a novel microstructure that consists of fine copper, silicon carbide and titanium carbide particulates together with a nominal in‐situ originated aluminium‐copper equilibrium phases distributed in a highly substructured aluminium based matrix with a significant dislocation density (7.56 ⋅ 1014 m‐2).