热喷涂高铝含量锌铝涂层的耐腐蚀性能研究

Study on the Corrosion Resistance of Thermal Spraying Zinc Aluminum Coating with High Aluminum Content

为了探究高铝含量的锌铝涂层的耐腐蚀性能,通过热喷涂技术制备了3种高铝含量的锌铝涂层,采用超景深显微镜、电化学极化曲线、电化学阻抗谱(EIS)、X射线衍射仪(XRD)等手段,分析了不同铝含量的锌铝涂层的耐腐蚀性能。结果表明:含Zn涂层在腐蚀过程中首先发生锌的活化溶解,涂层表面附着的腐蚀产物使得涂层表现出微弱的自封闭效果;Zn-Al60涂层兼有锌的阴极保护作用和铝的钝化屏蔽作用,在3种涂层中表现出最优的耐腐蚀性能。

In order to explore the corrosion resistance of zinc-aluminum coatings with high aluminum content,the thermal spraying technology was applied to produce three kinds of high-aluminum zinc-aluminum coatings.The corrosion resistance of zinc aluminum coatings with different aluminum contents were investigated by ultra-depth filed microscope,electrochemical polarization curves,electrochemical impedance spectroscopy(EIS)and X-ray diffractometer(XRD).Results showed that the Zn-containing coating first underwent the activation and dissolution of zinc during the corrosion process,and the corrosion products attached to the coating surface induced that the coating exhibited a weak self-sealing effect.Furthermore,owing to holding the cathodic protection of zinc and the passivation shielding effect of aluminum,the Zn-Al60 coating presented the optimal corrosion resistance among the three kinds of coatings.