Microscopic characteristics and corrosion resistance of 7075 aluminum alloy modified by friction stir processing

This study aimed to carry out the friction stir processing (FSP) modification of 7075 aluminum alloy mainly by slotting the base metal and adding the reinforcing phase, and to explore the electrochemical corrosion performance of the modified area. The results showed that the added phases with different mass fractions of TiB2, TiC, and Cf were beneficial to improve the electrochemical corrosion performance of the modified area. Among them, the TiB2 and TiC at different mass fractions had a relatively small improvement in the electrochemical corrosion performance of the FSP-modified area of the base metal, and both had a negative effect when the mass fraction was 5%. The Cf addition phase with a mass fraction of 2% had the most obvious improvement effect. Its corrosion potential E0 was −0.771 V, and the corrosion current density I0 was 4.80875E-6 A · cm2. The analysis showed that the electrochemical performance of Cf and the bonding performance with the base metal were better, and the corrosion process of the base metal could be suppressed during the corrosion process.