Sarkar N K, Redmond W, Schwaninger B, Goldberg A J
J Oral Rehabil. 1983 Mar;10(2):121-8. doi: 10.1111/j.1365-2842.1983.tb00106.x.
Potentiodynamic cyclic polarization of four orthodontic alloys (wires), namely Permachrome, Elgiloy, a beta-titanium alloy and Nitinol in a 1% NaCl solution within -500 mV and +300 mV (SCE) indicated the first three alloys to be passive whereas breakdown of passivity was observed on Nitinol. The SEM examination of the pre- and post-polarized alloy surfaces provided evidence which was consistent with the electrochemical measurements, in that the first three alloys exhibited no appreciable corrosion damage whereas pitting corrosion was observed on Nitinol. The results obtained from X-ray analysis of the pitted surface indicated that this pitting could be due to selective dissolution of nickel from Nitinol.
四种正畸合金（金属丝），即帕马铬合金、埃尔吉洛伊耐蚀合金、一种β钛合金和镍钛合金，在1%氯化钠溶液中于-500毫伏至+300毫伏（饱和甘汞电极）范围内进行动电位循环极化，结果表明前三种合金呈钝态，而镍钛合金出现了钝化膜破裂。对极化前后合金表面进行的扫描电子显微镜检查所提供的证据与电化学测量结果一致，即前三种合金没有明显的腐蚀损伤，而镍钛合金上观察到了点蚀。对出现点蚀的表面进行X射线分析所得到的结果表明，这种点蚀可能是由于镍从镍钛合金中选择性溶解所致。
