60Si2Mn钢表面激光熔覆铁基涂层的组织及耐磨性研究  

Microstructure and Wear Resistance of Laser Cladded Iron-based Coatings on 60Si2Mn Steel

作　　者：曹新娜 宋路阳 黄玲玲 江涛 张浩强 汪瑞军[3] 于华[1,2] 詹华 尹丹青[1,2] 鲍曼雨[3] 龙伟民 钟素娟[4] 纠永涛 CAO Xinna;SONG Luyang;HUANG Lingling;JIANG Tao;ZHANG Haoqiang;WANG Ruijun;YU Hua;ZHAN Hua;YIN Danqing;BAO Manyu;LONG Weimin;ZHONG Sujuan;JIU Yongtao(School of Material Science and Engineering,Henan University of Science and Technology,Henan Luoyang 471000,China;Longmen Laboratory,Henan Luoyang 471000,China;Chinese Academy of Agricultural Mechanization Sciences Group Co.,Ltd.,Beijing 100083,China;Zhengzhou Research Institute of Mechanical Engineering Co.,Ltd.,Zhengzhou 450000,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471000 [2]龙门实验室,河南洛阳471000 [3]中国农业机械化科学研究院集团有限公司,北京100083 [4]郑州机械研究所有限公司,郑州450000

出　　处：《表面技术》2024年第7期164-170,共7页Surface Technology

基　　金：2021年产业基础再造和制造业高质量发展专项项目(TC210H02X-04);金属材料磨损控制与成型技术国家地方联合工程研究中心2021年开放课题(HKDNM202104)。

摘　　要：目的提高60Si2Mn钢的表面耐磨损性能。方法采用同步送粉方式在60Si2Mn钢表面进行激光熔覆X1、X22种铁基粉末。通过金相显微镜、场发射扫描电镜和X射线衍射仪,观察和分析熔覆层的显微组织、化学元素分布及相组成,采用显微硬度仪、多功能摩擦磨损试验机进行硬度、耐磨损性能测试。结果2种熔覆层均无裂纹、气孔等缺陷,涂层内部存在大量树枝晶、等轴晶和少量沿基材表面生长的平面晶,其中X1熔覆层的顶部区域等轴晶数量较多,组织更细小均匀。2种熔覆层均由相同物相(α-Fe)固溶体组成,未出现明显的其他物相的衍射峰。基体60Si2Mn钢平均硬度约为300HV,X1熔覆层的硬度为950~1000HV,平均硬度为975HV。X2熔覆层的硬度为784~821HV,平均硬度为803HV。经过球-盘磨损试验后,X1、X2熔覆层以及基体的体积磨损率分别为1.32×10^(-4)、1.94×10^(-4)、3.29×10^(-4)mm^(3)/(N·m)。结论2种熔覆层的硬度和耐磨损性能均优于基体,其中X1熔覆层的平均硬度比X2熔覆层的高约21%,其体积磨损率最小,耐磨损性能更好。As an advanced surface strengthening and repairing technology,laser cladding is used to prepare metallurgically bonded coatings,which has the advantages of high surface quality,low dilution rate,small heat-affected zone in the base material,and low material loss.It has been widely utilized in many fields,such as agricultural machinery,aerospace,high-speed trains,railways,and mining machinery.In this study,laser cladding technology was employed to deposit two types of iron-based coatings on the surface of 60Si2Mn steel,which was commonly used as rotary tiller blade material.The microstructure,phase structure,hardness in the bonding zone,and wear resistance of the two cladding coatings were analyzed in detail.Both types of cladding coatings exhibited no cracks,pores,or other defects.They contained a significant number of dendritic crystals,equiaxed crystals,and a small number of planar crystals growing along the substrate surface.The different microstructures of the cladding coatings were related to the constitutional supercooling during the solidification process,which was primarily affected by the ratio of the temperature gradient(G)to the solidification rate(R).At the interface between the cladding coatings and the substrate,solidification firstly occurred with the largest temperature gradient and the slowest solidification rate.In this region,there was no significant constitutional supercooling,leading to the formation of a planar crystalline structure.As the solidification process continued,the temperature gradient decreased and the solidification rate increased.This resulted in a larger constitutional supercooling and interface instability.The microstructure changed from planar crystals to a mixture of columnar and dendritic crystals.When the solid-liquid interface approached the surface of the cladding coatings,the cooling rate was accelerated,corresponding to a smaller G/R.At this stage,the nucleation rate exceeded the growth rate of the grains,leading to the transformation of the microstructure into smalle

关 键 词：60SI2MN钢 激光熔覆 铁基粉末 微观组织 耐磨损性能 

分 类 号：TH117[机械工程—机械设计及理论]