Effect of Deep Cryogenic Treatment on Wear and Corrosion Resistance of an Al–Zn–Mg–Cu Alloy

The 7075 aluminum alloy was subjected to deep cryogenic treatment (DCT) at –196°C with liquid nitrogen for different hours. The wear and corrosion behaviors of the alloy were investigated by hardness, friction and wear, intergranular corrosion (IGC), and electrochemical corrosion tests. The microstructure of the alloy was observed by transmission electron microscope (TEM). The results showed that both the wear and corrosion resistance of the alloy treated with DCT could be improved. After the DCT 12 h, the matrix precipitates of the alloy were fine and homogeneously distributed, and the grain boundary precipitates of the alloy were discontinued, so that the alloy performed better comprehensive properties.