中国激光, 2014, 41 (12): 1203003, 网络出版: 2014-11-03
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
激光光学 激光熔覆 复合涂层 纳米TiC 微观组织 性能 laser optics laser cladding composite coating nano-TiC microstructure properties
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。
Abstract
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, Ni3B, 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 nano-TiC/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 nano-TiC/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.
柴龙顺, 王存山, 韩立影, 张娈. 纳米TiC/C对激光熔覆镍基合金涂层组织和性能的影响[J]. 中国激光, 2014, 41(12): 1203003. Chai Longshun, Wang Cunshan, Han Liying, Zhang Luan. Influence of Nano-TiC/C Content on Microstructure and Properties of Laser Clad Ni-based Alloy Coatings[J]. Chinese Journal of Lasers, 2014, 41(12): 1203003.