Effects of nanoparticles on the solution treatment and mechanical properties of nano-SiCp/Al-Cu composites

In this study, through the comparison of the microstructure evolution between composites and matrix alloy, the effects of nano-sized SiC particles (i.e. nano-SiCp) on solution behavior and properties of 1 wt.% nano-SiCp/Al-Cu composites were investigated for the first time. Results indicate that different from the traditional solution treatment process of Al-Cu matrix alloy, due to the hindering effect of nano-SiCp on the solution behavior of Al2Cu phase, the composites need higher solution temperature to show better mechanical properties. The T6 treated composites exhibit excellent hardness and tensile properties after solution treatment at 540 °C for 10 h. Its hardness, ultimate tensile strength and yield strength are 150 HV, 500 MPa and 350 MPa, which are increased by 120 %, 82 % and 106 % than that of the as-cast composites respectively. Compared with the T6 treated Al-Cu matrix alloy, the UTS and YS of nano-SiCp/Al-Cu composites are elevated by 16.3 % and 34.6 %, respectively.