激光熔覆Ni+20%Cr3C2涂层的成形特性  

Forming Characteristics of Ni+20% CrC Coating by Laser Cladding

作　　者：李大胜 张杰 孟普 杨丽 Li Dasheng;Zhang Jie;Meng Pu;Yang Li(College of Mechanical and Vehicle Engineering,Bengbu University,Bengbu,Anhui 233000,China)

机构地区：[1]蚌埠学院机械与车辆工程学院,安徽蚌埠233000

出　　处：《应用激光》2021年第3期447-453,共7页Applied Laser

基　　金：安徽省教育厅高校自然科学重点项目(KJ2018A0568);蚌埠学院自然科学重点研究项目(2020ZR01zd);蚌埠学院自然科学研究项目(2020ZR01)。

摘　　要：针对高含量陶瓷相的熔覆层容易出现裂纹的问题,研究了不同工艺参数下Ni45+20%Cr3C2熔覆层的成形特性,为调节工艺参数制备出高含量陶瓷相的无裂纹熔覆层提供相应的理论指导。研究结果表明:随着激光电流的增加,稀释率、熔高及熔宽均增大,熔宽的增加值大于熔高的增加值,熔覆层的组织比较粗大,晶距较大,晶粒生长方式由细小的树枝晶向胞状树枝晶转变;在优化的工艺参数下(电流150 A,扫描速度200 mm/min,搭接率60%),熔覆层的稀率为25.3%,多道熔覆层的硬度值略低于单道熔覆层,但性能相对均匀稳定。对于高含量陶瓷相的熔覆层,适当放宽对稀释率的控制范围,通过调节工艺参数,可以获得无裂纹、成形质量较好的熔覆层。Aiming at the problem that the cladding layer with high content of ceramic phase is prone to crack, the forming characteristics of Ni45 + 20% Cr3C2 cladding layer with different process parameters were studied, which provides the corresponding theoretical guidance for preparing the crack free cladding layer with high content of ceramic phase by adjusting the process parameters. The results show that: with the increase of laser current, the dilution ratio, melting height and melting width increase, the increase value of melting width is bigger than that of melting height, the microstructure of cladding layer is coarse, the crystal spacing is large, and the crystal growth mode changes from fine dendrite to cellular dendrite. Under the optimized process parameters(current 150 A, scanning speed 200 mm/min, lapping rate 60%), the rarefaction ratio of cladding layer is 25.3%, and the hardness of multi pass cladding layer is slightly lower than that of single pass cladding layer, but the performance is relatively uniform and stable. For the cladding layer with high content of ceramic phase, the control range of dilution ratio should be appropriately relaxed. By adjusting the process parameters, the cladding layer with good crack free forming quality can be obtained.

关 键 词：激光熔覆 Cr3C2/Ni涂层 工艺参数 成形质量 

分 类 号：TG132[一般工业技术—材料科学与工程]