Study on surface modification and wear and corrosion resistance of A356 aluminum alloy
In order to improve the surface wear resistance and corrosion resistance of A356 aluminum alloy, four kinds of high entropy alloy coatings (FeCoCrNi and FeCoCrNi+Mn/Cu/Ti) were prepared on the surface of A356 aluminum alloy by plasma spraying. The phase composition, microstructure, hardness, wear resistance and corrosion resistance of plasma spraying coatings were compared and ana-lyzed. The results show that the four kinds of plasma spraying coatings all have the diffraction peaks of face centered cubic solid solution and oxide, when the element Cu/Ti is added to FeCoCrNi, the Cu/Ti diffraction peaks also appear in the coatings. The thickness of the four plasma spraying coatings is be-tween 210 µm and 300 µm, and the interface between the coating and the substrate is mainly mechani-cal. The hardness and average friction coefficient of the four plasma spraying coatings are higher than that of A356 aluminum alloy substrate, the order of wear rate from low to high is: FeCoCrNi (coating Ⅰ)<FeCoCrNiTi(coating Ⅳ)<FeCoCrNiMn(coating Ⅱ)<FeCoCrNiCu(coating Ⅲ)<substrate. Com-pared with A356 aluminum alloy substrate, the corrosion potential of coating shifted forward, and the corrosion current density and pitting potential decreased, the Nyquist arc radius, impedance modulus |Z|0.01 Hz and charge transfer resistance Rct increased. The corrosion resistance of the four plasma spraying coatings is better than that of A356 aluminum alloy substrate, and the corrosion resistance of coating Ⅳ is the best.
万方数据
维普
