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-1Si and Al-11Si 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 σ (Al₃CuNi), Q (Al₅Cu₂Mg₈Si₆), τ₁ (Al₉FeNi) and Si particles. At 200°C to 300°C, the yield and ultimate tensile strength of Al-11Si were higher than Al-1Si. It can be found that the mount of intermetallic σ particles increasing will increase the deformation resistance whereas Si particle is detrimental. However, at elevated temperatures, Al-1Si would exhibit a higher elongation at 450°C but Al-11Si was higher than Al-1Si after 400°C. Microstructural observations showed Si particles would restrain the failure of matrix and increase the ductility.