超声空化下不锈钢钝化膜的半导行为

SEMICONDUCTING BEHAVIORS OF PASSIVE FILMS OF STAINLESS STEEL UNDER ULTRASONIC CAVITATION

采用极化曲线、电化学阻抗谱(EIS)和电位电容法,在静态和超声波空化的条件下,研究了不锈钢在1 mol/L HCl溶液中的电化学腐蚀行为.结果表明,静态条件下,0Cr13Ni5Mo和1Cr18Ni9Ti不锈钢均发生了钝化,钝化膜呈多层结构分布;空化条件下,钝化膜的稳定性降低,半导特性发生反转.静态条件下,0Cr13Ni5Mo不锈钢钝化膜的半导特性是p-型;空化使半导特性转变为n-型.静态条件下,在低电位区1Cr18Ni9Ti不锈钢钝化膜的半导特性是n-型,在高电位区是p-型;空化条件下,在低电位区1Cr18Ni9Ti不锈钢钝化膜半导特性显示p-型,在高电位区显示n-型.钝化膜半导性质转变的差异与其Fermi能级的高低相关.

The corrosion behaviors of passive films of two stainless steels, OCrl3Ni5Mo and 1Cr18Ni9Ti, under the conditions of static state （quiescence） and ultrasonic cavitations in 1 mol/L HC1 solution have been studied by means of polarization curves, EIS and capacitance potential measurements. The results indicate that the stainless steels all were passivated, and the passive films show a distribution of multi-layer structure under the is decreased, and the semiconducting properties conditions of quiescence; the stability of passive films are inversed at the situations of cavitation. For the film of OCrl3Ni5Mo the property transfored from p-type under the conditions of quiescence to n-type under the conditions of cavitation. For the film of 1Crl8Ni9Ti the property transfored from n-type in low potential and p-type in high potential under the conditions of quiescence to p-type and n- type under the conditions of cavitation, respectively. The transformation difference of semiconducting properties for different passive films is related to Fermi energy level of semiconductor.