纳米TiC/C对激光熔覆镍基合金涂层组织和性能的影响  

Influence of Nano-TiC/C Content on Microstructure and Properties of Laser Clad Ni-based Alloy Coatings

作　　者：柴龙顺 王存山[1] 韩立影[1,2] 张娈[1] 

机构地区：[1]大连理工大学三束材料改性教育部重点实验室,辽宁大连116024 [2]辽宁科技大学材料与冶金学院,辽宁鞍山114051

出　　处：《中国激光》2014年第12期70-76,共7页Chinese Journal of Lasers

基　　金：中航工业产学研专项

摘　　要：采用激光熔覆技术在38CrMoAl钢表面制备了不同纳米TiC/C添加量的镍基复合涂层。利用现代微观分析技术和性能检测手段,系统分析了纳米TiC/C添加量对镍基复合涂层微观组织形貌和性能的影响规律。结果表明,不同纳米TiC/C添加量镍基复合涂层主要是由γ-Ni、Ni3B和M23C6相组成。但有所不同的是,随着纳米TiC/C添加量的增加,γ-Ni树枝晶的数量呈现出先增后减的变化趋势,而其尺寸的变化趋势则相反。在纳米TiC/C的质量分数超过3.5%时,组织中开始有明显TiC颗粒存在,且其数量和尺寸呈逐渐增加的变化趋势。由于受晶粒细化和TiC硬质强化这两个关键因素的影响,复合涂层的硬度随着纳米TiC/C添加量的增加而升高,而耐磨性则在纳米TiC/C添加量为5.0%时达到最高,其源于细小TiC硬质相低的缺陷及其与周围基体高的协调变形能力。Ni-based composite coatings with different nano-TiC/C additions are prepared by laser cladding on the 38CrMoAl steel substrate. The influence of nano-TiC/C on the microstructure and properties of the coatings is investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Vickers hardness tester, and friction wear testing machine. The results show that the composite coatings mainly consist of γ-Ni, Ni3 B, and M23C6 phases. But what changes is that with the increase of the nano-TiC/C additions, the numbers of the primary γ-Ni dendrites present the trend of first increasing and then decreasing, whereas their sizes change is reversed. The TiC particles are observed as the nano-TiC/C addition mass fraction is higher than 3.5%, and their sizes and number gradually increase with the further increase of the nanoiTiC/C addition. The hardness values of the composite coatings gradually increase with increase of the nano-TiC/C additions, as a result of the refinement of the solidified structure and the reinforcement of the TiC particle. Whereas the wear resistance is the highest as nanoiTiC/C addition is 5.0 %, which results from high surface and internal perfections of the fine TiC particle, as well as its good compatible deformation capability with the surrounding matrix.

关 键 词：激光光学 激光熔覆 复合涂层 纳米TIC 微观组织 性能 

分 类 号：TN249[电子电信—物理电子学] TG174.44[金属学及工艺—金属表面处理]