45钢激光熔覆TiC涂层的制备及性能  

Preparation and properties of TiC coating on 45 steel by laser cladding

作　　者：刘志玲 常明丰[1] 韩贵生 戴姣燕[2] 徐金富 Liu Zhiling;Chang Mingfeng;Han Guisheng;Dai Jiaoyan;Xu Jinfu(School of Materials Science and Engineering,Chang'an University,Xi'an Shaanxi 710061,China;School of Materials Science and Chemical Engineering,Ningbo University of Technology,Ningbo Zhejiang 315211,China)

机构地区：[1]长安大学材料科学与工程学院,陕西西安710061 [2]宁波工程学院材料与化学工程学院,浙江宁波315211

出　　处：《金属热处理》2024年第3期269-274,共6页Heat Treatment of Metals

基　　金：宁波市重点研发计划(2023Z024)。

摘　　要：利用Ni60+TiC梯度层结构,通过CO_(2)恒流激光器在45钢表面制备了TiC涂层,研究了工艺参数(激光功率、搭接率和扫描速率)对TiC涂层组织和性能的影响。结果表明,随着激光功率和扫描速率的增加,涂层表面裂纹先减后增,当激光功率为4.0 kW,扫描速率为400 mm/min时,涂层表面裂纹消失;随着搭接率的增加,涂层表面裂纹先增后减,搭接率至50%时,涂层表面裂纹消失。最佳工艺参数为:激光功率4.0 kW、扫描速率400 mm/min、搭接率50%,其处理后的TiC梯度涂层厚度约为1.2 mm,与基体层呈冶金结合,最表层组织为树枝状TiC及少量Ni基固溶体,梯度层组织为TiC+Ni基固溶体,TiC含量由表及里呈梯度减少,Ni基固溶体含量由表及里呈梯度增加;TiC涂层的显微硬度由表及里从1968 HV0.2梯度下降至240 HV0.2;TiC涂层的磨损率为1.757×10^(-15)m^(3)/(N·m)。TiC coatings were cladded on the surface of 45 steel by a CO_2 constant current laser using Ni60+TiC gradient layer structure.The effect of process parameters(laser power,scanning rate and overlap rate)on the microstructure and properties of TiC coatings was investigated.The results show that the surface cracks of the coating decrease and then increase with the increase of laser power and scanning rate.The surface cracks disappear when the laser power is 4.0 kW and the scanning rate is 400 mm/min.With the increase of the overlap rate,the surface cracks of the coating increase and then decrease,and the surface cracks of the coating disappear when the overlap rate is 50%.The optimal process parameters are laser power 4.0 kW,scanning rate 400 mm/min,and overlap rate 50%.The thickness of TiC gradient coating is about 1.2 mm after the best process,and it is metallurgically bonded with the base layer.The microstructure of the most superficial layer is dendritic TiC and a small amount of Ni-based solid solution,the microstructure of the gradient layer is TiC+Ni-based solid solution,TiC content from the surface to the inside is in a gradient decrease,Ni-based solid solution content from the surface to the inside is in a gradient increase.The hardness of TiC coating decreases from 1968 HV0.2 to 240 HV0.2.In addition,the wear rate of the TiC coating is 1.757×10^(-15)m^(3)/(N·m).

关 键 词：TIC涂层 梯度层 工艺参数 摩擦磨损 

分 类 号：TG335.3[金属学及工艺—金属压力加工]