Relationship Between Heat Treatment And Mechanical Properties Of Al-Si-Mg Alloy

Abstract

Abstract The relationship between heat treatment and mechanical properties of Al-Si-Mg alloy was investigated. Solution treatment at 808K for 6 hours, preliminary aging at room temperature for 60 hours and artificial aging at 473K for 1 hours were conducted. Not preliminary aged samples were prepared for comparison. The strength improved and the elongation decreased with increasing the amount of Mg. This trend was seen both preliminary aged and not preliminary aged samples. However, preliminary aged samples showed relatively high tensile strength and elongation comparing with not preliminary aged samples. EPMA analysis revealed that the precipitation of Mg2Si in preliminary aged samples was larger than that of not preliminary aged samples, and which possibly contributed to the improvement of strength of the preliminary aged samples. Thermodynamic calculation showed that Mg2Si phase was not undissolved at the solution temperature, 808K, and these undissolved Mg2Si particles might influenced on mechanical properties negatively.