铁基激光熔敷层搭接与非搭接区摩擦性能  

Tribological properties of overlap and non-overlap zones in laser-clad iron-based coatings

作　　者：吴影[1,2] 刘艳 陈文静[3] 陈辉[1] WU Ying;LIU Yan;CHEN Wenjing;CHEN Hui(School of Materials Science and Engineering,Southwest Jiaotong University,Chengdu 610031,China;Department of Mechanical Engineering,Tsinghua University,Beijing 100084,China;School of Materials Science and Engineering,Xihua University,Chengdu 610039,China)

机构地区：[1]西南交通大学材料科学与工程学院,成都610031 [2]清华大学机械工程系,北京100084 [3]西华大学材料科学与工程学院,成都610039

出　　处：《清华大学学报（自然科学版）》2022年第3期476-481,共6页Journal of Tsinghua University(Science and Technology)

基　　金：国家重点研发计划项目(2016YFB1100202)。

摘　　要：多层多道激光熔敷涂层的组织呈周期性变化规律,总体分为搭接区和非搭接区。为研究涂层中不同区域的摩擦磨损性能,该文采用线性往复摩擦试验,分别设定5和25 N的压力,150和300 s的摩擦时长对铁基涂层的搭接区与非搭接区的摩擦磨损性能进行研究,并结合不同区域的组织和物相的分析,讨论了摩擦性能与组织之间的关系,及摩擦过程中组织的演变规律。研究结果表明:在低压力下,抗磨损性能受组织影响较大,搭接区由于组织粗大、α-Fe含量较少,其抗磨损性能较差;而非搭接区组织细密、α-Fe含量较多,其抗磨损性能较好。在高压力下,抗磨损性能受组织影响较小,搭接区与非搭接区的抗磨损性能相似。在摩擦试验过程中,磨痕浅表层产生剪切变形层,其厚度、硬度及等效应变量随压力和摩擦时长的增加而增加,其中搭接区硬度增加速率高于非搭接区。The microstructures of multi-pass laser cladding coatings exhibit periodic changes that are generally divided into overlap and non-overlap zones. The tribological properties of these two zones were studied using linear reciprocating friction tests with forces of 5 and 25 N and friction times of 150 and 300 s. This study analyzed the tribological characteristics with analyses of the microstructures and phases in the two zones. The results show the relationship between the tribological effects and the microstructure and the evolution of the microstructure during the friction process. The results show that at low pressures, the anti-wear characteristics are greatly affected by the microstructure. The overlap zone has poor wear resistance due to the coarse microstructure and less α-Fe content while the non-overlap zone with a finer microstructure and high α-Fe content has better wear resistance. At high pressures, the wear characteristics are less affected by the microstructure with the anti-wear characteristics of the overlap zone being similar to those of the non-overlap zone. The subsurface below the wear scar had a shear deformation layer after the friction test whose thickness, hardness and equivalent strain increased with increasing pressure and friction time. The overlap zone hardness increases faster than that of the non-overlap zone.

关 键 词：多道激光熔敷 搭接区与非搭接区 组织 摩擦性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]