内燃机用Ti600高温合金表面激光熔覆Ti/TiB2涂层组织和性能分析  

Surface Modification of Ti600 Alloy with Laser Cladded Ti/TiB2 Coatings for Internal Combustion Engine

作　　者：王洪波 靳兆文 康宝印 徐建 Wang Hongbo;Jin Zhaowen;Kang Baoyin;Xu Jian(Nanjing Vocational College of Science and Technology,Nanjing 210048,China;Zhejiang Industrial Vocational and Technical College,Shaoxing 312000,China;Nanjing Shuo'an Electromechanical Equipment Installation Co.,Ltd,Nanjing 210048,China)

机构地区：[1]南京科技职业学院,南京210048 [2]浙江工业职业技术学院电气电子工程学院,绍兴312000 [3]南京硕安机电设备安装有限公司,南京210048

出　　处：《真空科学与技术学报》2019年第12期1149-1153,共5页Chinese Journal of Vacuum Science and Technology

摘　　要：选择激光熔覆技术在Ti600表面制得Ti/TiB2复合涂层,分析不同激光比能条件下得到的涂层组织结构及其性能测试结果。研究表明:激光熔覆涂层和与基体达到了良好结合。TiB2发生熔融后生成了胞状TiB2,进一步固溶变为须状结构。涂层中部弥散态TiC与TiN晶核获得充分生长并跟TiB2颗粒一起生成发达枝晶结构。在涂层下部生成了颗粒状TiB2以及许多片层结构的双相组织。激光比能15 kJ/cm^2时,涂层达到了最高的显微硬度990HV,达到了基体硬度的近2.5倍。磨损量随着激光比能的增加表现出单调减小的变化,平均摩擦系数整体上随着激光比能的增加也表现出单调减小的变化。基体在磨损过程中形成了许多犁沟结构。在涂层的磨损表面形成了浅短磨痕与部分碎屑颗粒。The surfaces of Ti600 alloy,an internal combustion engine material,were modified with Ti/TiB2 composite coatings synthesized by laser cladding of Ti and TiB2 powders.The influence of the specific energy of laser on the microstructures,tribological behavior of the Ti/TiB2 coatings was investigated with X-ray diffraction,scanning electron microscopy and conventional mechanical probes.The results show that the specific energy of laser had a major impact.For instance,the Ti/TiB2 coatings with strong interfacial adhesion comprised cellular TiB2 grains/whiskers on the top,dispersed TiC/TiN nuclei and dendritic structures in the middle,and TiB2 grains and lamellar biphasic clusters at the bottom.As the specific energy increased,the micro-hardness changed in an increase-decrease mode,peaking to 990 HV at 15 kJ/cm^2,and the wear-rate and average friction coefficient monotonically decreased.Shallow wear-tracks and some scraps existed on worn surface of the coatings.

关 键 词：激光熔覆 激光比能 Ti600 Ti/TiB2涂层 微观组织 

分 类 号：TG174.44[金属学及工艺—金属表面处理]