Geng Zhanji, Zhang Mengling, Zhu Jianyong, Peng Yingbo, Zhang Wei, Liu Feng
Powder Metallurgy Research Institute, Central South University, Changsha 410083, China.
Changsha Huaxi New Material Co., Ltd., Changsha 410083, China.
Materials (Basel). 2023 Jun 25;16(13):4580. doi: 10.3390/ma16134580.
CrC-modified NiCr-TiC composite coatings were prepared using the plasma spraying technique for different CrC contents on the microstructure and the properties of the Ni-based TiC cladding layer were investigated. The microstructures of the coatings were characterized using scanning electron microscopy, and the friction and wear performance of the coating was evaluated by the wear tests. The results revealed that the surfaces of the CrC-modified NiCr-TiC composite coatings with varying CrC contents were dense and smooth. TiC was uniformly distributed throughout the entire coating, forming a gradient interface between the binder phase of the Ni-based alloy and the hard phase of TiC. At high temperatures, CrC decomposes, with some chromium diffusing and forming complex carbides around TiC, some chromium solubilizes with Fe, Ni, and other elements. An increase in chromium carbide content leads to an upward trend in hardness. The measured hardness of the coatings ranged from 600 to 850 HV3 and tended to increase with increasing CrC content. When the mass fraction of CrC reached 30%, the hardness increased to 850 HV3, and the cracks and defects were observed in the coating, resulting in a wear resistance decline.
采用等离子喷涂技术制备了不同CrC含量的CrC改性NiCr-TiC复合涂层，研究了CrC含量对Ni基TiC熔覆层组织和性能的影响。利用扫描电子显微镜对涂层的微观结构进行了表征，并通过磨损试验对涂层的摩擦磨损性能进行了评估。结果表明，不同CrC含量的CrC改性NiCr-TiC复合涂层表面致密光滑。TiC均匀分布在整个涂层中，在Ni基合金的粘结相和TiC的硬质相之间形成了梯度界面。在高温下，CrC分解，部分铬扩散并在TiC周围形成复合碳化物，部分铬与Fe、Ni等元素溶解。碳化铬含量的增加导致硬度呈上升趋势。涂层的实测硬度范围为600至850 HV3，并随CrC含量的增加而增加。当CrC的质量分数达到30%时，硬度增加到850 HV3，涂层中出现裂纹和缺陷，导致耐磨性下降。
