摘要
为增强轧辊表面硬度以提升轧辊工作寿命,采用1 kW光纤激光器在Cr12MoV表面制备M2高速钢熔覆层,探索最优激光工艺参数。通过着色探伤剂、X射线衍射仪及显微硬度仪,对不同激光功率和扫描速度下的熔覆层显微组织、成分、物相、硬度进行检测分析。结果表明:激光功率对熔覆层表面成形质量影响较大,扫描速度对其影响不明显;随激光功率增加,熔覆层表面平整度增强,裂纹数量降低,熔覆层组织成分分布越均匀,晶界偏析现象减弱,枝晶组织逐渐粗大,熔覆层显微硬度降低;熔覆层主要由Martensite、Austensite、Fe-Cr、MC、M_(2)C相组成,熔覆层内的组织主要是树枝晶和胞状晶,MC、M_(2)C等硬质相弥散分布在组织内;激光功率为1000 W,扫描速度为180 mm/min时,熔覆层表面无裂纹,最大显微硬度为1092HV_(0.2),是基体的2.63倍,满足工业性能需求。
In order to enhance the surface hardness of rolls to improve the working life of rolls,the M2 HSS fusion cladding layer on the surface of Cr12MoV was prepared by using a 1 kW fiber laser to explore the optimal laser process parameters.The microstructure,composition,physical phase and hardness of the molten layer at different laser power and scanning speed were examined and analyzed by using coloring probe,X-ray diffractometer and microhardness tester.The results show that the laser power has a large influence on the surface forming quality of the molten layer,and the scanning speed has no significant influence;with the increase of laser power,the surface flatness of the clad layer is enhanced,the number of cracks is reduced,the composition of the clad layer is more uniformly distributed,the grain boundary segregation phenomenon is weakened,the dendrite organization is gradually coarsened,and the microhardness of the clad layer is reduced;the melt layer is mainly composed of Martensite,Austensite,Fe-Cr,MC and M_(2)C phases,the organization within the melt layer is mainly dendritic and cytosolic,and hard phases such as MC and M_(2)C are diffusely distributed in the organization;when the laser power is 1000 W and the scanning speed is 180 mm/min,the surface of the molten layer is crack-free and the maximum microhardness is 1092HV_(0.2),which is 2.63 times that of the substrate,meeting the industrial performance requirements.
作者
陈皓
周浩
王新林
Chen Hao;Zhou Hao;Wang Xinlin(School of Mechanical Engineering,University of South China College,Hengyang,Hunan 421001,China;Ultra-fast Wiener Technolog‐yand Laser Advanced Manufacturing Hunan Provincial Key Laboratory,University of South China College,Hengyang,Hunan 421001,China;School of Electrical Engineering,University of South China College,Hengyang,Hunan 421001,China)
出处
《机电工程技术》
2023年第4期150-154,共5页
Mechanical & Electrical Engineering Technology
