The NiCrBSi-Y2O3 composite coatings were prepared on the surface of 45 carbon steel by plasma spray, the microstructure and tribological properties of the coatings were investigated. The results show that the NiCrBSi-...The NiCrBSi-Y2O3 composite coatings were prepared on the surface of 45 carbon steel by plasma spray, the microstructure and tribological properties of the coatings were investigated. The results show that the NiCrBSi-Y2O3 composite coatings are mainly composed of γ-Ni, CrB, Cr7C3 and Y2O3. With addition of Y2O3, hard phases such as CrB, Cr7C3 emerge in composite coating, and the density of the composite coatings also increases. The NiCrBSi-0.5Y2O3 composite coating presents excellent tribological properties. Its friction coefficient is 0.175, which is about 37% of that of the pure NiCrBSi coating. The mass wear loss is 1.2 mg, which is reduced by 43% compared with the pure NiCrBSi coating. When the loads are 6-10 N, the NiCrBSi-0.5Y2O3 composite coating suffers from slight wear and the wear mechanisms are mainly adhesive wear accompany with slight micro-cutting wear and micro-fracture wear. As the load increases to 12 N, the wear mechanisms are adhesive wear and severe micro-cutting wear.展开更多
Mo-based alloys are widely used for their excellent wear and corrosion resistance as well as high temperature resistance.Mo-NiCrBSi and Mo-Ni alloy coatings were prepared on 1020 water wall tube by laser cladding tech...Mo-based alloys are widely used for their excellent wear and corrosion resistance as well as high temperature resistance.Mo-NiCrBSi and Mo-Ni alloy coatings were prepared on 1020 water wall tube by laser cladding technology in the present study.The microstructure and phase compositions were analyzed by means of the scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS)and X-ray diffractometry(XRD).The corrosion properties of the coatings were evaluated by an electrochemical experiment at room temperature in 3.5 wt.%NaCl electrolyte.With increasing content of Mo,the structure homogeneity in Mo-Ni coatings deteriorated,the grain size increased,the average hardness and the corrosion resistance declined,due to the more content of harmful phases.Compared to the Mo-Ni coatings,the overall performance was better for the Mo-NiCrBSi,which had the higher hardness contributed by the element B and Si as well as the better corrosion resistance due to the addition of Cr.展开更多
文摘The NiCrBSi-Y2O3 composite coatings were prepared on the surface of 45 carbon steel by plasma spray, the microstructure and tribological properties of the coatings were investigated. The results show that the NiCrBSi-Y2O3 composite coatings are mainly composed of γ-Ni, CrB, Cr7C3 and Y2O3. With addition of Y2O3, hard phases such as CrB, Cr7C3 emerge in composite coating, and the density of the composite coatings also increases. The NiCrBSi-0.5Y2O3 composite coating presents excellent tribological properties. Its friction coefficient is 0.175, which is about 37% of that of the pure NiCrBSi coating. The mass wear loss is 1.2 mg, which is reduced by 43% compared with the pure NiCrBSi coating. When the loads are 6-10 N, the NiCrBSi-0.5Y2O3 composite coating suffers from slight wear and the wear mechanisms are mainly adhesive wear accompany with slight micro-cutting wear and micro-fracture wear. As the load increases to 12 N, the wear mechanisms are adhesive wear and severe micro-cutting wear.
基金supported by the National Natural Science Foundation of China(Grant Nos.11372110and 51101056)+1 种基金the National Science and Technology Support Program(Grant No.2011BAE12B03)the Fundamental Research Funds for the Central Universities(Grant No.12MS07)
文摘Mo-based alloys are widely used for their excellent wear and corrosion resistance as well as high temperature resistance.Mo-NiCrBSi and Mo-Ni alloy coatings were prepared on 1020 water wall tube by laser cladding technology in the present study.The microstructure and phase compositions were analyzed by means of the scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS)and X-ray diffractometry(XRD).The corrosion properties of the coatings were evaluated by an electrochemical experiment at room temperature in 3.5 wt.%NaCl electrolyte.With increasing content of Mo,the structure homogeneity in Mo-Ni coatings deteriorated,the grain size increased,the average hardness and the corrosion resistance declined,due to the more content of harmful phases.Compared to the Mo-Ni coatings,the overall performance was better for the Mo-NiCrBSi,which had the higher hardness contributed by the element B and Si as well as the better corrosion resistance due to the addition of Cr.