论文部分内容阅读
采用激光熔覆技术在H13钢表面制备出原位自生TiC颗粒增强Ni基复合涂层,利用扫描电镜、能谱仪和X射线衍射仪对熔覆层组织、成分和物相进行了分析,并测试了熔覆层显微硬度和耐磨性能。结果表明,激光熔覆层与基体呈良好的冶金结合,涂层中无裂纹、气孔等缺陷。涂层组织由γ-Ni、Cr7C3和TiC等相组成,原位自生TiC颗粒多呈菱形,尺寸在1~3μm之间,涂层显微硬度(800~1000 HV0.2)明显高于基体的显微硬度(300 HV0.2)。激光熔覆层中存在颗粒强化和细晶强化等多种强化作用,显著提高了H13钢的耐磨性能。
The in-situ TiC particles reinforced Ni-based composite coatings were prepared by laser cladding on the surface of H13 steel. The microstructure, composition and phase of the coatings were analyzed by scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. The micro-hardness and wear resistance of the coating were tested. The results show that the laser cladding layer has a good metallurgical bond with the substrate and no defects such as cracks and pores in the coating. The microstructure of the coating consists of γ-Ni, Cr7C3 and TiC phases. In-situ TiC particles are mostly rhomboid with the size of 1 ~ 3μm. The microhardness (800 ~ 1000 HV0.2) of the coating is obviously higher than that of the matrix Microhardness (300 HV0.2). There are many strengthening effects such as grain strengthening and fine grain strengthening in the laser cladding layer, which significantly improve the wear resistance of H13 steel.