【摘要】 采用电化学测试技术对TiNi形状记忆合金在Hank′s人工模拟体液和NaCl溶液中的腐蚀行为进行了研究。结果表明 ,TiNi合金阳极极化时 ,出现了低电位活性溶解。体系温度对TiNi合金的阳极极化无明显影响。但随着 pH的降低和Cl-的浓度的升高 ,孔蚀电位Eb 值负移 ,孔蚀敏感性增大。通过EPMA分析和SEM观察发现 ,低电位活性溶解形成的蚀孔内存在富Ti贫Ni的Ti2 Ni析出相 ,孔蚀主要在该处形成更多还原

【Abstract】 Corrosion behavior of TiNi shape memory alloys in artificial body fluids was investigated with electrochemical measurement technique. The results showed that the TiNi shape memory alloys sometimes dissolved at low electric potential when they were anodically polarized. The temperature had little effect on the anodically polarization behavior. But with the decrease of pH and increase of Cl - concentration, pitting potential(E b) shifted negatively. As a result, was also increased observations the pitting corrosion sensitivity. By means of EPMA and SEM were carried out on specimens showing dissolution at low potential, and many precipitates were found with high Ti and low Ni concentration in comparison with the matrix in the pitting hole. The Ti 2Ni intermetallic phase might provide preferential sites for pit initiation in TiNi shape memory alloys.更多还原