铸轧辊套超高速激光熔覆表面修复工艺研究  

Study on Surface Repairing Technology of Cast Rolling Sleeve by Ultra-high Speed Laser Cladding

作　　者：李辉 刘鹏宇 李志慧 魏小红 肖梦智 尹燕 张瑞华[1,3] LI Hui;LIU Pengyu;LI Zhihui;WEI Xiaohong;XIAO Mengzhi;YIN Yan;ZHANG Ruihua(Central Iron and Steel Research Institute,Beijing 100081,China;Sichuan Provincial Key Lab of Process Equipment and Control,Sichuan University of Science&Engineering,Zigong 643000,China;Yangjiang Hardware Knife Cut Industrial Technology Research Institute,Yangjiang 529533,China;Xinxiang Aviation Industry(Group)Co.,Ltd.,Xinxiang 453000,China;Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]钢铁研究总院,北京100081 [2]四川轻化工大学过程装备与控制工程四川省高校重点实验室,四川自贡643000 [3]阳江市五金刀剪产业技术研究院,广东阳江529533 [4]新乡航空工业(集团)有限公司,河南新乡453000 [5]兰州理工大学,甘肃兰州730050

出　　处：《热加工工艺》2024年第11期72-77,共6页Hot Working Technology

基　　金：国家自然科学基金项目(52161007);过程装备与控制工程四川省高校重点实验室开放基金资助项目(GK202104,GK202106);深圳市创新创业计划技术攻关重点项目(JSG G20210420091802007);海上风电高速激光熔覆防腐涂层制备工艺及应用项目(SDZX2020009)。

摘　　要：采用超高速激光熔覆在32Cr3Mo1V铸轧辊辊套表面制备了钴基合金层。采用单因素法分析了激光功率、熔覆速率、送粉速率对熔覆层成形质量的影响。结合铸轧辊套实际使用工况确定以熔覆层的厚度以及显微硬度作为考察对象,利用正交试验确定最优工艺参数,并借助扫描电镜对优选参数制备的熔覆层进行分析。结果表明,在一定参数范围内,熔覆层的厚度随送粉速率的增大而增大,随熔覆速率的增大而减小,并且与激光功率无明显相关性。优选的工艺参数为:激光功率2500 W、熔覆速率15 m/min和送粉速率30 g/min。该工艺制备的熔覆层显微组织非常均匀细小,存在明显的拱接分层现象,熔覆层底部和中部区域多为垂直于熔覆层/基体界面熔合线或搭接熔合线生长的柱状晶,生长方向具有高度的一致性,熔覆层顶部区域枝晶的生长方向相对紊乱,熔覆层的显微硬度显著高于基体,有利于提高铸轧辊辊套的耐磨性。Cobalt-based alloy layer was prepared on the surface of 32Cr3Mo1V cast rolling sleeve by ultra-high speed laser cladding.The effects of laser power,cladding rate and powder feeding rate on the forming quality of the cladding layer were analyzed by single factor method.Combined with the actual working conditions of the cast rolling sleeve,the thickness and microhardness of the fusion layer were determined as the investigation objects.The optimal process parameters were determined by orthogonal test,and the cladding layer prepared by the optimized parameters was analyzed by scanning electron microscope.The results show that within a certain range of parameters,the thickness of the cladding layer increases with the increase of the powder feeding rate and decreases with the increase of the cladding rate,and it has no obvious correlation with laser power.The optimized parameters are laser power of 2500 W,cladding rate of 15 m/min and powder feeding rate of 30 g/min.The microstructure of the fusion coating prepared by this process is very uniform and fine,and there is an obvious arching delamination phenomenon.The bottom and middle regions of the fusion coating are mostly columnar crystals perpendicular to the fusion line of the fusion layer/substrate interface or overlap fusion line.The growth direction has high consistency.The growth direction of dendrites at the top of the fusion layer is relatively disordered.The microhardness of the fusion layer is significantly higher than that of the substrate,which is beneficial to improve the wear resistance of the cast rolling sleeve.

关 键 词：超高速激光熔覆 钴基熔覆层 显微组织 

分 类 号：TG456.7[金属学及工艺—焊接]