다이캐스팅으로 제조된 Silafont-36 합금의 기계적 특성에 미치는 T6 열처리 영향

Silafont-36 alloy is an Al-Si-Mg based alloy widely used in automotive applications. Its mechanical properties can be changed through T5 or T6 heat treatment. In this study, we investigated the influence of T6 heat treatment on the mechanical properties of Silafont-36 alloy prepared by die casting. The standard T6 heat treatment condition is as follows: (1) solution heat treatment for 2 hours in vacuum atmosphere at 510°C and water quenching, and (2) artificial aging treatment for 4 hours at 180°C in vacuum atmosphere and air cooling. Heat treatments were applied based on the above treatment conditions with changes in the solution treatment and artificial aging treatment conditions. Tensile test, hardness test, and microstructure analysis were performed on the heat-treated specimens. As the solution treatment temperature increased, the tensile strength increased. On the other hand, tensile strength decreased with increasing aging temperature and holding time. From a microstructure analysis, it was confirmed that the tensile strength increased with decreasing secondary dendrite arm spacing.