海水环境下镍铝青铜合金的滑动摩擦-腐蚀行为及机理研究

Nickel-Aluminium-Bronze alloy（NAB）has good mechanical properties and excellent corrosion resistance, such as pitting corrosion resistance and stress corrosion resistance, especially under seawater condition. Compared with stainless steels and duplex stainless steels, NAB has better cost-effectiveness and become a potential marine structure material, so it is widely used to manufacture crucial parts and components in marine circumstance. In order to improve the reliability of such parts and components applied in seawater, tribocorrosion behavior and mechanism of NAB for sliding contacts under seawater condition is put forward and will be studied in this project. The project shows the important application of tribocorrosion, which has been a newly developing science, in marine engineering. The main researches are as follows: The dynamic relationships of the depassivation and repassivation process happened to NAB will be studied by electrochemical experiments. The synergistic effects between seawater corrosion and mechanical friction will be tested by tribocorrosion experients. On the basis of these experiments above, triobocorrosion mechanism model will be built, during which the "third body" appeared usually in friction and wear process will be taken into account adequately. The research results to be attained in the project will provide the important theory for the life forecasting and evaluation of NAB parts and components applied in seawater, and can direct the further application of other passive metal alloys in marine engineering in theoretical and practical way.

镍铝青铜合金具有良好的力学及耐腐蚀性能，其耐海水腐蚀性尤其突出，在抗点蚀、氯化物应力腐蚀等方面显著优于双相不锈钢，是具有良好成本效益且极具发展潜力的海洋结构材料，目前在国内外被广泛用于制造海洋设备关键零部件。为提高海水环境下镍铝青铜合金零部件的应用可靠性，本项目针对该类零部件的常见工况，提出研究其在海水腐蚀及机械摩擦共同作用下的滑动摩擦-腐蚀行为及机理。 本项目属"摩擦-腐蚀"这一新兴研究领域在海洋工程的应用，主要研究内容包括：通过电化学实验，研究镍铝青铜合金"去钝化-再钝化"的动力学规律；通过滑动摩擦-腐蚀实验，研究海水腐蚀与机械摩擦的协同效应；在实验基础上，充分考虑摩擦系统中"第三体"的作用，构建镍铝青铜合金的滑动摩擦-腐蚀机理模型。 本项目的研究结果不仅可为镍铝青铜合金关键零部件的寿命预测与评估提供重要理论依据，而且将为进一步开发钝化合金在海洋工程的广泛应用提供理论和实践指导。