ZM6镁合金冷喷涂Al涂层结构与耐蚀性研究

Structure and Anti-corrosion Properties of Cold Sprayed Al Coatings on ZM6 Magnesium Alloy

为提高镁合金耐蚀性,在ZM6基体上采用冷喷涂技术制备了纯铝涂层。用扫描电镜(SEM)、能量色散谱(EDS)、显微硬度测试仪等研究了涂层形貌结构和性能;利用电化学方法和中性盐雾实验对涂层的抗腐蚀性能进行了评价。结果表明:在ZM6基体上冷喷涂的铝涂层结构致密,孔隙率为0.8%,显微硬度HV平均为59.8,高于镁合金;结合力达到21MPa;涂层抗腐蚀性能优于镁合金,冷喷涂铝涂层的自腐蚀电位与镁合金相比较,提高了约700mV,中性盐雾实验200h无腐蚀,可为ZM6提供长效保护。

In order to improve anti-corrosion properties of magnesium alloy,Al coating on the ZM6 magnesium alloy was prepared by cold spray.The morphology and properties of coating were studied by scanning electronic microscope（SEM）,energy dispersive spectroscopy（EDS） and micro-hardness tester.The electrochemical method and the neutral salt-spray test were used to evaluate the corrosion resistance of coating.The results indicated that pure Al coatings with high density were obtained on the surface of ZM6 alloy by means of cold spray technology successfully and the porosity was 0.8%.The micro-hardness was 59.8,which was higher than that of ZM6 alloy.Bonding force reached 21MPa.The corrosion resistance of coatings was superior to that of ZM6.Corrosion potential of ZM6 shifted positively by about 700mV after being cold sprayed Al,and salt-spray fog resistance reached 200 hours.ZM6 with coatings got long-life protection.