(南京航空航天大学 机电学院，南京 210016)
摘 要: 采用动态电位极化和交流阻抗方法研究工业纯钛(CP-Ti Grade 2)和钛钯合金(Ti-0.2Pd Grade7)在模拟体液中的耐蚀性；研究热处理和等通道径角挤压(ECAP)处理获得的两种钛金属的显微组织对耐蚀性的影响；利用交流阻抗谱对各种处理方式得到的表层特征进行研究。结果表明：ECAP处理大幅度提高了两种金属的耐蚀性，马氏体组织的CP-Ti比魏氏组织的CP-Ti具有更高的耐蚀性，均匀等轴粗晶的空冷CP-Ti的腐蚀电流密度较低。ECAP处理的Ti-0.2Pd表面显示双层膜结构，其余处理方式的试样表面显示具有单层膜结构。
关键字: 纯钛；Ti-0.2Pd合金；电化学；耐腐蚀性；显微组织
（College of Mechanical and Electrical Engineering,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China）
Abstract:The corrosion resistance of commercial pure titanium (CP-Ti) and Ti-0.2Pd alloy in a simulated body fluid was investigated by cyclic polarization and electrochemical impedance spectroscopy (EIS). The effect of microstructure obtained by heat treatment and equal-channel angular pressing (ECAP) on the corrosion resistance was also studied for two kinds of metals. The properties of surface produced by different microstructures were characterized by the EIS analysis. The results show that both metals composed of martensitic phase have higher corrosion resistance than the metals composed of Widmannstatten phase. ECAP process can improve the corrosion resistance of both metals evidently. A coarse equiaxial-grained CP-Ti with homogeneous microstructure shows low corrosion current density. The surface on ECAPed Ti-0.2Pd shows double layer structure, and the surface on the rest of specimens show single layer structure.
Key words: pure Ti; Ti-0.2Pd alloy; electrochemical; corrosion resistance; microstructure
