及其耐腐蚀性能
( 1. 南通工学院 机械工程系, 南通 226007;
2. 南京航空航天大学 机电工程学院, 南京 210016;
3. 江苏大学 机械工程学院, 镇江 210013)
摘 要: 以纳米Al2O3粉末为填料, 采用激光重熔等离子喷涂陶瓷涂层技术, 在45号钢表面制备了纳米改性Al2O3+13%（质量分数）TiO2/nano-Al2O3复合陶瓷涂层。用X射线衍射仪、 扫描电镜研究了纳米Al2O3改性后的陶瓷涂层的组织及涂层的耐腐蚀性能。结果表明, 在激光的作用下, 原等离子喷涂层Al2O3+13%TiO2的片层状组织得以消除；激光重熔区亚稳相 γ-Al2O3转变为稳定相α-Al2O3, 重熔层由α-Al2O3和TiO2组成。 与等离子喷涂Al2O3及Al2O3+13%TiO2陶瓷涂层相比, 纳米Al2O3改性后的Al2O3+13%TiO2/nano-Al2O3陶瓷涂层致密化程度明显提高, 耐腐蚀性能也得到了明显的改善。
关键字: 纳米Al2O3颗粒; TiO2; 等离子喷涂; 激光重熔; 微观组织; 腐蚀
（ 1. Department of Mechanical Engineering,
Nantong Institute of Technology,
Nantong 226007, China;
2. College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and
Astronautics, Nanjing 210016, China;
3. College of Mechanical Engineering,
Jiangsu University, Zhenjiang 212013, China）
Abstract: Using nano-Al2O3 powder material as the coating stuff, laser was employed to remelt the plasma spraying coating. Composite ceramic coating of Al2O3＋13%TiO2/nano-Al2O3 was formed on 45# steel surface. The microstructure of laser-remelting nano-Al2O3 composite ceramic coating was investigated by using X-ray diffraction and scanning electronmicroscopy, and the corrosion behavior of the coatings was studied. The results show that lamella structure characteristic of plasma-sprayed coatings is eliminated after the laser-remelting. The metastable γ-Al2O3 in the remelting area transfers into stable phase of α-Al2O3 and composite ceramic coating consists of α-Al2O3 and TiO2 on Al2O3+13%TiO2/ nano-Al2O3 coatings. So laser-remelting nano-Al2O3 ceramic coating has higher densification and better corrosion resistance than plasma sprayed Al2O3 and Al2O3+13%TiO2 coatings does.
Key words: nano-Al2O3 particle; titania; plasma-spraying; laser remelting; microstructure; corrosion behavior
