基于残余应力分布优化的TBM滚刀刀圈激光熔覆涂层制备工艺研究  

Preparation of Laser Cladding Coating for TBM Cutter Ring Based on Optimization of Residual Stress Distribution

作　　者：崔少杰 王好平 莫继良[1,2] 蒙树立 段文军[1,3] 冯鉴 CUI Shao-jie;WANG Hao-ping;MO Ji-liang;MENG Shu-li;DUAN Wen-jun;FENG Jian(Tribological Design Laboratory of Shield/TBM Equipment,Southwest Jiaotong University,Chengdu 610031,China;School of Mechanical Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Engineering Services Co.,Ltd.,Chengdu 610083,China;Zongtech Genting(Sichuan)Tool Manufacturing Co.,Ltd.,Chengdu 611936,china)

机构地区：[1]西南交通大学盾构/TBM装备摩擦学设计实验室,成都610031 [2]西南交通大学机械工程学院,成都610031 [3]中铁工程服务有限公司,成都610083 [4]中德云岭(四川)工具制造有限责任公司,成都611936

出　　处：《表面技术》2023年第8期413-423,共11页Surface Technology

基　　金：国家自然科学基金(U22A20181、52005419);四川省科技重点研发项目(21ZDYF3658)。

摘　　要：目的为改善TBM(全断面隧道掘进机)涂层刀圈残余应力分布,针对刀圈涂层制备过程中的激光扫描路径开展研究,以优化刀圈涂层及涂层/基材界面的残余应力分布。方法使用MSC.Marc 2016软件建立了刀圈涂层制备的三维完全热机耦合模型,通过试验验证了模型的准确性,并针对激光熔覆过程中扫描顺序、扫描方向和扫描终点夹角等3个工艺变量开展了应力场分析研究。结果刀圈表面近涂层区周向/径向残余应力数值计算结果分布趋势与试验基本一致,且在涂层与基材结合的界面处,残余应力梯度达到最大,当激光扫描方向为安装孔到刃顶时,涂层刀圈残余应力的不合理分布得到了明显改善且应力最值显著降低,其中基材部分残余应力最高降低35 MPa,而调整扫描顺序和扫描终点夹角未能有效改善刀圈残余应力的分布及应力最值。结论通过合理设计熔覆过程中的扫描路线,可以有效改善刀圈涂层的残余应力分布并降低残余应力最值,对延长TBM涂层刀圈服役寿命具有重要的指导意义。Metal-matrix ceramic coating can be prepared on the surface of TBM(Tunnel Boring Machine)cutter ring by laser cladding technology to improve the wear resistance,but the residual stress distribution of cutter ring significantly changes in the preparing process.The unreasonable distribution of residual stress of coating may cause low cycle fatigue fracture of cutter ring in service.In this study,the influence of scanning path on stress distribution and maximum/minimum value of stress is studied during the process of coating preparation to decrease the failure risk of TBM coated cutter ring,which will provide theoretical guidance for optimizing the residual stress distribution of coated cutter ring.A 3D fully thermo-mechanical coupling model of coated cutter ring is established based on the practical laser cladding process(the scanning sequence is"cutter edge→cutter edge→blade",the scanning direction is from blade to mounting hole and the angle between scanning end points is 120°)of coated TBM cutter ring by MSC.Marc 2016.The radial and hoop residual stress at eight points on the coated cutter ring is measured by X-ray residual stress tester.Compared to the simulation results,it is indicating that the distribution of hoop and radial residual stress near the coated region on the surface of cutter ring by numerical simulation are basically consistent with the experimental results.Moreover,the average residual stress in coating region is 2-3 times higher than that in substrate.The residual stress gradient is the largest at the interface between the coating and substrate.To explore the influence of process variables(scanning sequence,scanning direction and angle between scanning end points)on residual stress distribution of coated cutter ring in laser cladding process,four optimization schemes are designed based on the practical process.Note that these four schemes only change one of process variables compared with the practical process.In summary,according to the numerical simulation results,the unreasonable distr

关 键 词：TBM滚刀刀圈 激光熔覆涂层 数值仿真 工艺优化 残余应力分布 

分 类 号：V261.8[航空宇航科学与技术—航空宇航制造工程]