Abstract
Al-Si alloy, known for its excellent corrosion resistance and high strength, is utilized across various industries, such as electric vehicles, requiring light metal parts for efficiency. Heat treatment is an effective process for enhancing the performance of Al-Si alloys by controlling the microstructure and precipitation. Optimized heat treatment improves the mechanical properties of Al-Si alloy, including strength, hardness, and corrosion resistance. In this study, the effect of heat treatment on the microstructure, corrosion resistance, and hardness of A356 casting alloy, which has recently been used in electric vehicles, was analyzed. The as-cast A356 alloy was used as a control sample, with a solid solution treatment, followed by aging treatment. The results showed that the hardness and corrosion resistance of A356 alloy can be changed by controlling the formation and distribution of Mg(2)Si precipitates within the microstructure through the solution heat treatment and following aging. Additionally, the distribution and strengthening mechanism of Mg(2)Si precipitates were examined using XRD. With increasing aging time, more Mg(2)Si precipitates were formed, increasing hardness. However, the precipitation of Mg(2)Si reduces the corrosion resistance of A356 alloy. Thus, it was revealed that the heat treatment of A356 alloy for enhancing mechanical properties by precipitating Mg(2)Si causes a side effect of corrosion resistance.