激光与等离子复合制备的隔热涂层微观特性与力学性能研究  

Microstructure and Mechanical Properties of Thermal Insulating Coating Prepared by Laser and Plasma

作　　者：崔静[1] 郭玉珠 庞铭 杨广峰[1] Cui Jing;Guo Yuzhu;Pang Ming;Yang Guangfeng(Airport College,Civil Auiation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学机场学院,天津300300

出　　处：《激光与光电子学进展》2020年第15期134-140,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金联合基金(U1633111);中国民航大学蓝天青年学者培养经费项目;中国民航大学科研启动基金(2011QD21X,09QD05X)。

摘　　要：采用超音速等离子喷涂技术与激光重熔工艺复合制备氧化锆隔热涂层,通过光学显微镜、扫描电镜、能谱仪、X射线衍射仪和硬度仪分别表征了氧化锆涂层的宏观形貌、显微组织、元素分布、物相结构以及硬度分布。结果表明,激光与等离子复合制备的涂层物相由亚稳定四方晶相与立方晶相组成。涂层的横截面呈碗状形貌,且上边缘凹凸不平。复合制备工艺消除了原超音速等离子喷涂涂层内部的层状结构以及孔隙、微裂纹,提高了涂层的致密度,且重熔后涂层与基体的连接方式变为冶金结合。重熔后得到的基体组织自上而下从条状晶、针状晶逐渐变为细小的针状晶和珠光体,热影响区组织为等轴晶。重熔涂层的平均硬度约为原等离子涂层硬度的3倍。In this work,supersonic plasma spraying technology and the laser remelting process are used to prepare the zirconia thermal insulating coating.The macroscopic morphology of the zirconia coating is characterized by optical microscope,scanning microscope,energy spectrometer,X-ray diffractometer,and hardness tester.The results show that the coating phase prepared by laser and plasma composite consists of metastable tetragonal crystal phase and cubic crystal phase.The cross-section of the coating is bowl-shaped,and the upper edge is uneven.The composite preparation process eliminates the layered structure,pores,and micro-cracks in the original supersonic plasma spray coating,improves the density of the coating,and the connection between the coating and the substrate becomes metallurgical after remelting.The matrix structure obtained after remelting gradually changes from strip-shaped crystal and needle-shaped crystal to fine needle-shaped crystal and perlite from top to bottom,and the structure of the heat-affected zone is equiaxed crystal.The average hardness of the remelted coating is about three times of the hardness of the original plasma coating.

关 键 词：激光重熔 等离子喷涂 氧化锆 微观组织 显微硬度 

分 类 号：V261.8[航空宇航科学与技术—航空宇航制造工程]