Research Progress on Microstructure Control and Strengthening Mechanisms of Aluminum Alloys for New Energy Vehicles

Against the backdrop of rapid advancements in lightweighting and integrated die-casting technologies for new energy vehicles, aluminum alloys have emerged as the core lightweight material for automotive structural components due to their excellent specific strength, corrosion resistance, and formability. However, traditional die-cast aluminum alloys generally rely on heat treatment processes to achieve strength and toughness. This not only significantly increases process costs and production lead times, but also leads to critical defects such as blistering and dimensional distortion in large integrated die-castings during heat treatment. Consequently, the development of high-strength and high-toughness die-cast aluminum alloys that meet service requirements in their as-cast state has become an urgent industry need. Although significant progress has been made in recent years in the research on microstructural control and performance enhancement of die-cast aluminum alloys for automotive applications, a systematic, integrated analysis of the strengthening mechanisms for the two mainstream alloy systems-Al-Si-Mg and Al-Mg-Si-remains lacking. This paper systematically reviews the microstructural evolution patterns and intrinsic mechanisms of performance enhancement for these two alloy systems, providing important theoretical references for the composition design and microstructural control of next-generation high-strength, high-toughness aluminum alloys without subsequent heat treatment, as well as supporting the further development of lightweighting technologies for new energy vehicles.