铝镁及稀土铝镁电弧喷涂涂层的耐腐蚀性能研究  

Study of Corrosion Resistance of Al-Mg and Re-Al-Mg Arc Spraying Coatings

作　　者：李承宇[1] 严生贵[1] 王会阳[1] 晁兵[1] 

机构地区：[1]江苏中矿大正表面工程技术有限公司,徐州221008

出　　处：《热喷涂技术》2012年第4期20-26,共7页Thermal Spray Technology

基　　金：2010年江苏省科技支撑计划项目(BZ2010049)

摘　　要：采用电弧喷涂技术在Q235钢表面制备了Al-Mg和Re-Al-Mg涂层,分别研究了这两种涂层的耐腐蚀性能,利用中性盐雾试验及电化学测试等试验方法研究了两种涂层的防腐蚀性能并通过扫描电子显微镜分析了Al-Mg和Re-Al-Mg涂层腐蚀前后的微观组织形貌,并讨论了涂层的结构及耐蚀机理,结果表明两种涂层在极化过程中都出现了明显的钝化现象,两种涂层在腐蚀过程中表面都会生成一层氧化膜,起到了物理屏蔽作用延缓了涂层的腐蚀速率,但稀土铝镁合金涂层的防腐蚀性能明显优于铝镁合金涂层,这是由于稀土元素的加入,降低了涂层的孔隙率,使涂层具有了良好的耐腐蚀性能。稀土铝镁合金涂层在中性盐雾试验中表现出的腐蚀速率是最慢的,电化学试验过程中其表现出钝化区域最大,具有良好的腐蚀与防护性能。Al-Mg and Re-Al-Mg coatings are prepared on Q235 steel surface by arc spraying technology. The corrosion resistance of Al-Mg and Re-Al-Mg coatings was studied respectively. The neutral salt spray test and electrochemical test have been used to study the corrosion resistance of the two coatings, and the microstructure of Al and Re-Al-Mg coatings before and after corrosion were analyzed by scanning electronic microscope. Then, the structure and anticorrosive mechanism are analyzed. The results show that there is a clear passive phenomenon of two kinds of coatings in the polarization process, and a layer of oxide film on the coating surface in the process of corrosion is generated, it is a physical shield which can delay the corrosion rate of coating, but the corrosion resistance performance of Re-Al-Mg coating is better than Al-Mg coating obviously, it＇ s because by the rare earth elements added, it reduces the porosity of the coating, increasing the hardness of the coating and the bond strength with substrate, resulting in a coating with good corrosion resistance.

关 键 词：电弧喷涂 涂层 稀土 防腐蚀 

分 类 号：TG174.4[金属学及工艺—金属表面处理]