ZrO2薄膜/不锈钢基腐蚀性能的数值模拟研究

Numerical Simulation of Corrosion Behavior of ZrO2 Film/Stainless Steel Substrate

采用溶胶-凝胶法在不锈钢基体上制备得到ZrO2薄膜.利用电化学工作站对不锈钢与覆膜不锈钢试样在5%的NaCl溶液进行动电位扫描测试.结果表明:ZrO2薄膜可以提高不锈钢的耐腐蚀性能.运用有限单元法(FEM)建立了覆膜不锈钢腐蚀的数值模型,模拟结果表明:实验中动电位扫描下的电流密度与模拟结果具有良好的一致性.通过有限元模型所建立的电解质电位分布图发现,随着电位的正向移动,电极表面的缺陷区与非缺陷区易形成腐蚀微电池体系,从而发生点蚀现象.

ZrO 2 thin films were prepared on stainless steel substrate by sol-gel method.The electrochemical workstation was used for potentiodynamic scanning of stainless steel and coated stainless steel in 5% NaCl solution.The results show that ZrO 2 film can improve the corrosion resistance of stainless steel.A numerical model of corrosion of coated stainless steel was established by finite element method (FEM).The simulation results show that the current density under potentiodynamic scanning is in good agreement with the simulation results.Through the electrolyte potential distribution map established by finite element model,it is found that with the positive movement of the potential, the corrosion micro-battery system is easy to form in the defective and non-defective areas of the electrode surface ,which results in pitting corrosion.