Underwater friction surfacing of AA7075 aluminum alloy

This paper takes AA7075 aluminum alloy friction plates and homogeneous bar materials as the materials, and successfully conducts the friction surfacing experiment in the underwater environment, and compares it with the surfacing situation in the air environment. Through a systematic analysis of the macroscopic morphology, microstructure, hardness, tensile properties, and corrosion resistance of the underwater surfacing layer, the research results show that the underwater environment has a promoting effect on the friction surfacing process. The deposition efficiency is increased by 13.6 % compared with that of surfacing in the air, and the cooling rate of the surfacing layer is significantly accelerated. In this environment, the grains of the surfacing layer are refined by about 17 % compared with those in the air environment, and the heat - affected zone is greatly reduced due to the cooling effect of water. In terms of tensile properties, the tensile strength of the surfacing layer in underwater environment is increased by 12 %, and the elongation is significantly increased by 124 %, and the plasticity and toughness are improved. In terms of corrosion resistance, the corrosion rate of the surfacing layer in the water bath environment decreases, and the corrosion resistance is enhanced. This research provides a new theoretical basis for the optimization and application of the aluminum alloy friction surfacing process.