Fan Li, Chen Haiyan, Zhu Guangkuo, Cao Qizheng, Dong Lihua
College of Mechanical and Electronic Engineering, Shanghai Jian Qiao University, Shanghai 201306, China.
College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China.
Materials (Basel). 2023 Sep 27;16(19):6444. doi: 10.3390/ma16196444.
Three groups of spherical WB-reinforced Co-based coatings (Co coating, Co + 15%WB coating, Co + 45%WB coating) were fabricated by laser-cladded technology. The microstructure and constituent phase of spherical WB-reinforced Co-based coatings were examined through scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The low-temperature tribological properties were analyzed by coefficient of friction, 2D and 3D profiles across the wear track, and wear surface morphology, respectively. The results showed that the phases in the WB-reinforced Co-based coatings are mainly γ-Co, carbides CrC and CrC, WB, and WO. Under dry sliding friction at -20 °C, the more spherical WB, the lower the friction coefficient. The wear rate of Co + 45%WB coating was as low as 3.567 × 10 mm/N·m, indicating the outstanding wear resistance. Abrasive wear was observed on the rough surface of the WB-added coatings. Compared with dry sliding, due to the plastic deformation of micro-convexes and lubrication function in the 3.5 wt.% NaCl solution, the wear tracks on the surfaces of the three tested coatings were shallower, exhibiting distinct elongated plough grooves.
采用激光熔覆技术制备了三组球形WB增强Co基涂层（Co涂层、Co + 15%WB涂层、Co + 45%WB涂层）。通过扫描电子显微镜（SEM）结合能谱仪（EDS）和X射线衍射（XRD）对球形WB增强Co基涂层的微观结构和组成相进行了研究。分别通过摩擦系数、磨损轨迹的二维和三维轮廓以及磨损表面形貌分析了低温摩擦学性能。结果表明，WB增强Co基涂层中的相主要为γ-Co、碳化物CrC和CrC、WB以及WO。在-20℃干滑动摩擦条件下，球形WB越多，摩擦系数越低。Co + 45%WB涂层的磨损率低至3.567×10⁻⁶mm²/N·m，表明其具有优异的耐磨性。在添加WB的涂层粗糙表面观察到磨粒磨损。与干滑动相比，由于微凸体的塑性变形以及3.5 wt.% NaCl溶液中的润滑作用，三种测试涂层表面的磨损轨迹更浅，呈现出明显的拉长犁沟。
