TiC添加量对高能激光熔覆Inconel718基陶瓷涂层显微组织和摩擦磨损性能的影响  

Effect of TiC Content on Microstructure,Friction and Wear Properties of Inconel718 Based Ceramic Coatings Prepared by High Energy Laser Cladding

作　　者：吴军[1,2] 金杰 朱冬冬[1,2] 徐军飞[1,2] 张玉良 WU Jun;JIN Jie;ZHU Dong-dong;XU Jun-fei;ZHANG Yu-liang(Quzhou University,Quzhou 324000,China;Key Laboratory of Air-driven Equipment Technology of Zhejiang Province,Quzhou 324000,China;Zhejiang University of Technology,Hangzhou 310032,China)

机构地区：[1]衢州学院,浙江衢州324000 [2]浙江省空气动力装备技术重点实验室,浙江衢州324000 [3]浙江工业大学,杭州310032

出　　处：《表面技术》2021年第9期225-235,共11页Surface Technology

基　　金：国家自然科学基金项目(51801112,51501100);浙江省自然科学基金项目(Y18E01)。

摘　　要：目的针对Inconel718镍基高温合金耐磨性不足的问题,制备小尺度TiC增强Inconel718镍基高温合金耐磨复合材料,提升其硬度及耐磨性。方法利用4000 W高能激光束快速熔融制备TiC/Inconel718基陶瓷复合涂层,并针对TiC质量分数分别为5%、15%、25%的复合涂层,依次进行物相成分、显微组织、压痕硬度、摩擦磨损性能等方面的分析。结果随着TiC含量的增加,γ-(Ni,Cr,Fe)基体上析出的TiC小尺度颗粒逐渐增多,显微组织明显细化,TiC晶界处偏聚了大量Nb、Mo元素,并与Ti元素置换生成了铌、钼类碳化物。同时,(Nb,Ti)C复合型碳化物和Laves相的析出,进一步提升了复合涂层的显微硬度,由297 HV_(0.2)逐步提升至408 HV_(0.2),摩擦系数从0.3402降低至0.2628,磨损率从35.15×10^(-4)g/(N·m)减少至5.96×10^(-4)g/(N·m),磨损机制由严重的粘着磨损转变为以磨粒磨损和氧化磨损为主。结论通过高能激光熔覆制备小尺度TiC增强体颗粒,可细化复合涂层的显微组织,其显微硬度随TiC含量的增加而相应提高。在磨损试验过程中,TiC/Inconel718陶瓷复合涂层表现出良好的减摩和耐磨性能。In order to solve the problem of poor wear resistance of Inconel 718 superalloy,small scale TiC reinforced Inconel718 superalloy composites were prepared to improve its hardness and wear resistance.The TiC/Inconel718-based ceramic composite coating was prepared by melting with 4000 W high energy laser beam.The phase composition,microstructure,microhardness,friction and wear properties of the composite coatings with 5wt.%,15wt.%and 25wt.%TiC were systematically analyzed.The results show that the volume fraction of small scale TiC particles,which precipitated on theγ-(Ni,Cr,Fe)matrix,increased gradually with the increase of TiC content and the grain size of the matrix obviously decreased.A large amount of Nb and Mo elements were segregated at the grain boundary of TiC and the titanium element was replaced by niobium and molybdenum elements to form niobium and molybdenum composite carbides.Meanwhile,the microhardness of the composite coating was further improved by the precipitation of(Nb,Ti)C composite carbides and Laves phase.The microhardness of the coating increased gradually from 297HV_(0.2)to 408HV_(0.2).The friction coefficient decreased from 0.3402 to 0.2628.The wear rate decreased from35.15×10^(-4)g/(N·m)to 5.96×10^(-4)g/(N·m),the typical wear mechanism changed from severe adhesive wear to abrasive wear and oxidative wear.After high energy laser cladding,the grain size of the composite coating was refined and the microhardness was increased gradually with the increase of TiC contents.During the wear test,excellent friction reduction and wear resistance of TiC/Inconel718 ceramic composite coating were obtained.

关 键 词：激光熔覆 复合涂层 显微组织 摩擦磨损 

分 类 号：TG115.58[金属学及工艺—物理冶金]