Effect of nano-SiC content on mechanical properties of SiC/2014Al composites fabricated by powder metallurgy combined with hot extrusion

Nano-SiC particulates (n-SiCp) reinforced 2014Al matrix composites with different reinforcement volume fractions (0, 0.25, 0.5 and 1 vol.-%) were fabricated by powder metallurgy combined with hot extrusion. The effect of volume fraction of n-SiCp on mechanical properties of composites was studied at both ambient and elevated temperatures. The increase of n-SiCp content led to an increase in yield strength (YS) and ultimate tensile strength (UTS) and a slight decrease in elongation which is much better than the composites reinforced with micro-SiCp. The 0.5 vol.-% n-SiCp/2014Al composite observed the highest YS and UTS of similar to 378 and similar to 573 MPa at room temperature and of similar to 303 and similar to 409 MPa at 473 K. The enhancement of the properties is suggested to be induced by uniformly dispersed and well-bonded n-SiCp reinforcements as well as the age-hardening effect of the more and finer precipitates.