超声空化下不锈钢钝化膜的半导行为

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.

Semiconducting properties of passive films of stainless steel in ultrasonic cavitation

Abstract: The corrosion behaviors of passive films of stainless steel 0Cr13Ni5Mo at the conditions of static state (quiescence) and ultrasonic cavitations in the hydrochloric acid solutions have been studied by means of electrochemical impedance spectroscopy (EIS) and capacitance potential measurements. The results indicated that the passive films showed a distribution of multi-layer structure and properties of p-type semiconducting in the conditions of quiescence. The outer-layer passive films were damaged and transformed to n-type semiconducting properties in the conditions of ultrasonic cavitations, with anode currents increased and corrosion rate accelerated. The local high temperature caused by cavitations lead to the increase of densities of donor (electron) in layer of passive films and the inversion of semiconducting properties.