Abstract:In this paper, the Al-Si-Mg-Cr alloy was prepared by vacuum electromagnetic induction melting furnace. Thermo-calc software was used for thermodynamic simulation, and SEM, EDS and other test methods were used to characterize the microstructure of Al-Si-Mg-Cr alloy under different heat treatment conditions tissue and test its mechanical properties. The corrosion properties of the experimental alloys were tested by weight loss method and electrochemical method. The results show that the main phases of the experimental alloy include primary α-Al, (α-Al+Si) eutectic, Al13Cr4Si4, β-Al (Cr, Fe) Si, and Fe-rich phases (β-Al5FeSi and π-AlSiMgFe). After heat treatment, the experimental alloy structure was refined, the eutectic area is reduced, the eutectic Si was spheroidized, and the Al13Cr4Si4,β-Al(Cr, Fe)Si phases were dispersed and distributed in the alloy. The corrosion test results show that the main corrosion mode of the experimental alloy is intergranular corrosion. After heat treatment, the eutectic area of the experimental alloy decreases, which leads to the narrowing of the corrosion channel and improves the corrosion resistance of the alloy. When the heat treatment process is 535℃ 6h+160 26h, the micromechanical properties and corrosion resistance of the experimental alloy are the best.