Al-Ti-Si-RE高速电弧喷涂层热震与电化学腐蚀行为  

Thermal Shock and Electrochemical Corrosion Behaviors of High Speed Arc Sprayed Al-Ti-Si-RE Coating

作　　者：童辉[1,2] 魏世丞[2] 刘毅[2] 田浩亮[2] 王新坤[2] 徐滨士[2] 

机构地区：[1]北京工业大学,北京100124 [2]装甲兵工程学院装备再制造技术国防科技重点实验室,北京100072

出　　处：《稀有金属材料与工程》2015年第4期1000-1005,共6页Rare Metal Materials and Engineering

基　　金：国家重点基础研究发展计划('973'计划)(2011CB013403);国家自然科学基金项目(51222510);国家高技术研究发展计划('863'计划)(2013AA040203)

摘　　要：通过对Al-Ti-Si-RE涂层抗热震性能以及热震前后电化学腐蚀行为分析研究,发现Al-Ti-Si-RE涂层在500℃时能够保持良好的抗热震性能,且在热震前后耐电化学腐蚀性能没有明显下降,主要原因是Ti在高速电弧喷涂过程中,与Al结合反应放热,使涂层与基体'冶金结合'部位增多,提高了涂层结合强度。同时经透射电镜(TEM)观察,喷涂层中晶粒尺寸较小,且Al与钛铝金属间化合物具有良好共格关系,降低了Al-Ti-Si-RE涂层开裂敏感度。另外Al-Ti-Si-RE涂层具有发达的'骨架'结构,电化学腐蚀过程中形成的Al氧化物能够有效填充到'骨架'孔隙和热震引起的微裂纹当中,对涂层同时起到'自封闭'与'自修复'作用,使其更加致密并兼具良好抗热震性能与耐电化学腐蚀性能。The thermal shock resistance and electrochemical corrosion behaviors of A1-Ti-Si-RE coating before and after thermal shock were investigated. The results show that the AI-Ti-Si-RE coating could keep good thermal shock resistance at 500 ℃, and the electrochemical corrosion resistance before and after thermal shock does not decline sharply, which is caused by more metallurgical combinations between the coating and the substrate due to the reaction heat of Ti and A1 in the high speed electric arc spraying process. At the same time, by transmission electron microscopy （TEM） observation, the grain sizes of the coating are small, and AI and Ti-A1 intermetallics have a good coherency, which could all reduce the coating cracking sensitivity. In addition, A1-Ti-Si-RE coating has a good cage construction, whose voids and coating cracks could be sealed by A1 oxides, and it could play the role of self-sealing and self-healing, and make the coating thicker with good resistances of thermal shock and electrochemical corrosion.

关 键 词：高速电弧喷涂 Al-Ti-Si-RE涂层 结合强度 热震试验 电化学腐蚀 

分 类 号：TG174.4[金属学及工艺—金属表面处理]