摘要
采用微弧表面处理技术(微弧氧化MAO和微弧复合MCC)在AZ31B镁合金基体上制备出不同断面结构的防护涂层。通过电化学腐蚀及腐蚀疲劳测试方法,研究了MAO、MCC涂层的电化学腐蚀及腐蚀疲劳性能。结果表明,生长10 min的MAO涂层具有较好的耐电化学腐蚀性能。MAO涂层表面存在微孔和微裂纹,在应力条件下微孔和微裂纹作为疲劳断裂的裂纹萌生点,可加速裂纹的萌生与扩展,使其腐蚀疲劳寿命相较AZ31B合金基体降低了55%。而具有MCC涂层的AZ31B合金试样腐蚀疲劳极限为(64.0±5.4) MPa,比AZ31B合金基体提高了59%。在低应力载荷下(<80 MPa),微弧复合涂层试样的腐蚀疲劳强度得到明显提高。
Protective coatings with different section structures were prepared on AZ31 B magnesium alloy by using micro-arc surface treatment(micro-arc oxidation MAO and micro-arc composite MCC). The electrochemical corrosion and corrosion fatigue properties were studied by electrochemical corrosion and corrosion fatigue tests. The results show that the MAO coating treated for 10 min shows better corrosion resistance. It is observed that there are micro-pores and micro-cracks on the surface of MAO coating on the AZ31 B alloy. These micro-pores and micro-cracks are deemed as crack initiation points of fatigue cracks and can accelerate the initiation and propagation of cracks under stress conditions, which lead to a reduction of 55% in the corrosion fatigue life compared with that of the AZ31 B alloy substrate. The corrosion fatigue limit of AZ31 B alloy with MCC coating is(64.0±5.4) MPa, which is 59% higher than that of the AZ31 B alloy substrate. Under low stress condition(<80 MPa), the corrosion fatigue strength of the AZ31 B alloy with MCC coating is significantly improved.
作者
申毅
薛玉娜
陈汉
戴荣
王秒
耿永辉
张鑫圆
蒋百灵
Shen Yi;Xue Yuna;Chen Han;Dai Rong;Wang Miao;Geng Yonghui;Zhang Xinyuan;Jiang Bailing(School of Materials Science and Engineering,Xi'an Shiyou University,Xi'an Shaanxi 710065,China;Technical Monitoring Center of Changqing Oilfield Branch,Xi'an Shanxi 710018,China;Training Center of Changqing Oilfield Branch,Xi'an Shaanxi 710014,China;School of Materials Science and Engineering,Xi'an University of Technology,Xi'an Shaanxi 710048,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2022年第8期257-265,共9页
Heat Treatment of Metals
基金
陕西省自然科学基础研究计划青年项目(2022JQ-339)
陕西省自然科学基础研究计划面上项目(2021JM-412)。
关键词
AZ31B镁合金
微弧表面处理
电化学腐蚀
腐蚀疲劳
AZ31B magnesium alloy
micro-arc surface treatment
electrochemical corrosion
corrosion fatigue
