论文部分内容阅读
用动电位极化和电化学阻抗等方法检测1Cr18Ni9Ti、304和316三种奥氏体不锈钢在3.5%NaCl溶液中的点蚀敏感性;用恒电位下的计时电流法结合激光电子散斑干涉技术(ESPI)实时监测这三种材料在3.5%NaCl溶液中阳极极化过程的表面动态变化及点蚀感应时间(τ)。结果表明,当电极表面发生点蚀时,激光电子散斑干涉图上会出现由点蚀产物扩散引起的亮斑。1Cr18Ni9Ti和304不锈钢的τ值分别是1s和9s,316不锈钢的τ值大于50s。由此可以判断1Cr18Ni9Ti的点蚀敏感性最大,304居中,316的点蚀敏感性最小。此结果与动电位极化和电化学阻抗等电化学方法得出的结果一致。激光电子散斑干涉技术可以做为一种实验室方法监测金属早期点蚀敏感性。
The pitting sensitivity of three kinds of austenitic stainless steels 1Cr18Ni9Ti, 304 and 316 in 3.5% NaCl solution was measured by potentiodynamic polarization and electrochemical impedance spectroscopy. Chronopotentiometry under constant potentials combined with laser speckle speckle interferometry (ESPI) real-time monitoring of the surface dynamic changes and pitting induction time (τ) of these three materials in anodic polarization in 3.5% NaCl solution. The results show that when the pitting occurs on the surface of the electrode, the speckle of laser speckle will appear on the interference pattern caused by the proliferation of pitting products caused by bright spots. The values of τ of 1Cr18Ni9Ti and 304 stainless steel are 1s and 9s, respectively, while those of 316 stainless steel are greater than 50s. It can be judged 1Cr18Ni9Ti maximum pitting sensitivity, 304 middle, 316 pitting sensitivity of the smallest. The results are consistent with those obtained by electrochemical methods such as potentiodynamic polarization and electrochemical impedance. Laser-electronic speckle speckle interferometry can be used as a laboratory method to monitor metal pitting susceptibility early.