Li D G, Wang J D, Chen D R, Liang P
State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
Ultrason Sonochem. 2015 Sep;26:99-110. doi: 10.1016/j.ultsonch.2015.02.013. Epub 2015 Mar 5.
The influences of oxygen and nitrogen on the ultrasonic cavitation erosion of Ti in 0.35%NaCl solution at room temperature, were investigated using a magnetostrictive-induced ultrasonic cavitation erosion (CE) facility and scanning electron microscopy (SEM). The roles of oxygen and nitrogen in the composition and the electronic property of the passive film on Ti, were studied by Mott-Schottky plot and X-ray photoelectron spectroscopy (XPS). The results showed that the mass loss of Ti in 0.35%NaCl solution increased with increasing cavitation time. Bubbling oxygen can evidently increase the resistance of ultrasonic cavitation erosion comparing with bubbling nitrogen. XPS results showed that the thickness of the passive film on Ti in 0.35%NaCl solution in the case of bubbling oxygen for 3 weeks, was about 7 nm, and the passive film was mainly composed of TiO2 with an anatase structure. While TiO2 with a rutile structure was found to be the major component of the passive film on Ti in 0.35%NaCl solution in the case of bubbling nitrogen for 3 weeks, and the film thickness was 5 nm. The results extracted from Mott-Schottky plot showed that the passive film on Ti in the case of bubbling oxygen had more donor density than the passive film on Ti in the case of bubbling nitrogen.
利用磁致伸缩诱导超声空蚀（CE）装置和扫描电子显微镜（SEM），研究了氧和氮对室温下0.35%NaCl溶液中Ti超声空蚀的影响。通过Mott - Schottky曲线和X射线光电子能谱（XPS）研究了氧和氮在Ti上钝化膜的组成和电子性质中的作用。结果表明，Ti在0.35%NaCl溶液中的质量损失随空蚀时间的增加而增加。与通入氮气相比，通入氧气能明显提高超声空蚀的抗性。XPS结果表明，在0.35%NaCl溶液中通入氧气3周的情况下，Ti上钝化膜的厚度约为7nm，钝化膜主要由具有锐钛矿结构的TiO₂组成。而在0.35%NaCl溶液中通入氮气3周的情况下，发现具有金红石结构的TiO₂是Ti上钝化膜的主要成分，膜厚度为5nm。从Mott - Schottky曲线得出的结果表明，通入氧气情况下Ti上的钝化膜比通入氮气情况下Ti上的钝化膜具有更高的施主密度。
