(1. 南昌航空大学 材料科学与工程学院,南昌 330063;
2. 南昌航空大学 信息工程学院,南昌 330063;
3. 海军工程大学 理学院,武汉 430033)
摘 要: 采用激光-感应复合熔覆方法,在黄铜基材表面制备Cu-Fe合金涂层,研究涂层的显微组织与性能特征。结果表明,当激光扫描速度为3000 mm/min、粉末流量为110 g/min时,在黄铜基材上获得表面较光滑、无气孔与裂纹的Cu-Fe合金涂层。另外,Cu-Fe合金在激光-感应复合熔覆过程中发生液相分离,在涂层底部,过饱和的金属基体α-Fe呈平面状与柱状枝晶生长;在涂层中上部,直径不等的球状颗粒α-Fe镶嵌在过饱和的金属基体ε-Cu内,许多细小的白色粒状物ε-Cu在球状颗粒α-Fe内均匀弥散析出,涂层的平均显微硬度相对于基材的提高约 2.8倍。
关键字: Cu-Fe合金涂层;黄铜基材;激光-感应复合熔覆;显微结构
(1. School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, China;
2. School of Information Engineering, Nanchang Hangkong University, Nanchang 330063, China;
3. School of Science, Naval University of Engineering, Wuhan 430033, China)
Abstract:Cu-Fe alloy coating was produced on the brass substrate by laser-induction hybrid cladding (LIHC). The microstructure and property of the coating were investigated. The results show that during LIHC when the laser scanning speed and powder feeding rate are 3000 mm/min and 110 g/min, respectively, the smooth, pore-free and crack-free Cu-Fe coating on the substrate is obtained. Furthermore, the liquid phase separation of Cu-Fe alloy takes place during LIHC. At the bottom of the coating, the supersaturated metal matrix identified as α-Fe presents the characteristics of planar growth and columnar dendritic growth. In the center of the coating, the spherical particles identified as α-Fe with different sizes are embedded in the supersaturated metal matrix ε-Cu. Large amounts of fine and white grains identified as ε-Cu phase precipitate inside the spherical α-Fe particles. As a result, the average microhardness of coating is about 2.8 times higher than that of the brass substrate.
Key words: Cu-Fe alloy coating; brass substrate; laser-induction hybrid cladding (LIHC); microstructure