Effect of Silicon Particles on the Tensile Properties of Heat Resistant Al-Si-Cu-Ni-Mg Alloy Pertaining to Different Tensile Temperature

The deformation behavior of Al-1 Si and Al-11 Si aluminum alloy in hot tensile procedure from 200 C to 450 C was investigated in this study. The results indicated that the flow stress was strongly dependent on second phase particles of δ (Al₃CuNi), Q (Al₅Cu₂Mg₈Si₆), τ1 (Al₉FeNi) and Si particles. At 200 °C to 300 °C, the yield and ultimate tensile strength of Al-11 Si were higher than Al-1 Si. It can be found that the mount of intermetallic δ particles increasing will increase the deformation resistance whereas Si particle is detrimental. However, at elevated temperatures, Al-1 Si would exhibit a higher elongation at 450 °C but Al-11 Si was higher than Al-1 Si after 400 °C. Microstructural observations showed Si particles would restrain the failure of matrix and increase the ductility.