原位轧制对电弧增材修复高强度低合金钢微观组织和力学性能的影响  

Effect of in-situ rolling on the microstructure and mechanical properties of wire-arc additive-remanufacturing renovated high-strength low-alloy steel

作　　者：任杰 王锐 王行涛 折洁 任欣 卢兵 祝弘滨 REN Jie;WANG Rui;WANG Xingtao;SHE Jie;REN Xin;LU Bing;ZHU Hongbin(CRRC Industrial Institute Co.,Ltd.,Beijing 100070,China;CRRC Industrial Technology Innovation(Beijing)Co.,Ltd.,Beijing 100096,China;School of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China;CRRC Industrial Institute(Qingdao)Co.,Ltd.,Qingdao,Shandong 266109,China)

机构地区：[1]中车工业研究院有限公司,北京100070 [2]中车科技创新(北京)有限公司,北京100096 [3]北京工业大学材料科学与工程学院,北京100124 [4]中车工业研究院(青岛)有限公司,山东青岛266109

出　　处：《轨道交通材料》2024年第6期8-15,共8页Materials for Rail Transportation System

基　　金：中车集团重点科研项目(CIJS23-KJ011)。

摘　　要：研究采用低合金钢焊丝,通过电弧熔丝结合原位轧制(HR-WAAM)复合增材技术对42CrMo电机轴进行修复,并利用电子背散射衍射(EBSD)等方法系统研究了原位轧制和热循环效应对增材修复高强度低合金(HSLA)钢微观组织和力学性能的影响。结果表明,引入原位轧制后,原奥氏体晶粒尺寸由457.7μm减小至68.1μm,变形组织和再结晶组织的占比分别增加了27%和13%。逐层沉积过程中的热循环效应可进一步促进材料的亚动态与静态再结晶并细化晶粒。受热循环影响的修复组织平均晶粒尺寸进一步减小至26.4μm,变形组织占比降低至11%,再结晶组织占比增长至31%。经过原位轧制和热处理后,HR-WAAM样品的屈服强度、抗拉强度和总延伸率分别提高至934 MPa、1002 MPa和10.8%,其综合力学性能优于42CrMo母材。本研究成果为HR-WAAM技术在轨道交通轴类零部件高性能修复领域的应用提供了理论依据和数据参考。Low-alloy steel welding wire combined with in-situ rolling(HR-WAAM)complex additive manufacturing techniques are applied to repair 42CrMo motor shafts.The effects of in-situ rolling and thermal cycling on the microstructure and mechanical properties of high-strength low-alloy(HSLA)steel for additive-manufacturing repair are systematically investigated using methods such as electron backscattering diffraction(EBSD).The research results show that,with the introduction of in-situ rolling,the original austenite grain size decreases from 457.7μm to 68.1μm,and the proportion of deformed and recrystallized structures increases by 27%and 13%,respectively.The thermal cycling effect during the layer-by-layer deposition process can further promote the sub-dynamic and static recrystallization of the material and refine the grain size.The average grain size of the repaired microstructure under the thermal cycling influence further decreases to 26.4μm,the proportion of deformed structure decreases to 11%,and the proportion of recrystallized structure increases to 31%.After in-situ rolling operation and heat treatment,the yield strength,tensile strength and total elongation of the HR-WAAM sample are increased to 934 MPa,1002 MPa,and 10.8%,respectively.Its comprehensive mechanical properties are superior to those of the 42CrMo base material.The results of this study provide theoretical basis and data reference for the application of HR-WAAM technology in the field of high-performance repair of axle components for rail transit industry.

关 键 词：原位轧制 电弧增材 高强度低合金钢 微观组织 力学性能 

分 类 号：U270.64[机械工程—车辆工程]