Bergant Zoran, Batič Barbara Šetina, Felde Imre, Šturm Roman, Sedlaček Marko
Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva 6, 1000 Ljubljana, Slovenia.
Institute of Metals and Technology Ljubljana, Lepi pot 11, 1000 Ljubljana, Slovenia.
Materials (Basel). 2022 Jan 4;15(1):342. doi: 10.3390/ma15010342.
NiCrBSi, WC-12Co and NiCrBSi with 30, 40 and 50 wt.% WC-12Co coatings were produced on low carbon steel by laser cladding with an Nd:YAG laser with a multi-jet coaxial cladding-nozzle. The microstructure properties after WC-12Co alloying were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and Vickers hardness tests. The resulting microstructures consisted of a γ-Ni and NiB matrix, strengthened with Co and W, NiSi, CrB, CrC3, CrC, WC/WC phases. In coatings with 30, 40 and 50 wt.% WC-12Co, a solid solution, strengthened multi-matrix NiCrWCo phase formed, which yielded a higher matrix hardness. Wear tests that monitored the friction coefficients were performed with a tribometer that contained a ball-on-disc configuration, AlO counter-body and reciprocal sliding mode at room temperature. The major wear mode on the NiCrBSi coatings without the WC-12Co was adhesive with a high wear rate and visible material loss by flaking, delamination and micro-ploughing. The addition of WC-12Co to the NiCrBSi coating significantly increased the wear resistance and changed the major wear mechanism from adhesion to three-body abrasion and fatigue wear.
采用Nd:YAG激光器和多喷嘴同轴熔覆头，通过激光熔覆在低碳钢上制备了NiCrBSi、WC-12Co以及含有30%、40%和50%（质量分数）WC-12Co的NiCrBSi涂层。通过扫描电子显微镜（SEM）、能谱仪（EDS）、X射线衍射仪（XRD）、电子背散射衍射仪（EBSD）和维氏硬度测试，研究了WC-12Co合金化后的微观结构性能。所得微观结构由γ-Ni和NiB基体组成，并通过Co、W、NiSi、CrB、CrC3、CrC、WC/WC相强化。在含有30%、40%和50%（质量分数）WC-12Co的涂层中，形成了一种固溶强化的多基体NiCrWCo相，其基体硬度更高。在室温下，使用含有球-盘配置、Al2O3对偶体和往复滑动模式的摩擦磨损试验机进行了监测摩擦系数的磨损试验。不含WC-12Co的NiCrBSi涂层的主要磨损模式为粘着磨损，磨损率高，有明显的材料剥落、分层和微犁削造成的材料损失。向NiCrBSi涂层中添加WC-12Co显著提高了耐磨性，并将主要磨损机制从粘着磨损转变为三体磨料磨损和疲劳磨损。
