Microstructure And Wear Resistance Of Different Sprayed Coatings On T10 Steel Surface

According to statistics, 70% of the cause in the die failure is surface wear and corrosion, also, about 1/3 of the energy in the mould manufacturing and use is directly consumed in friction and wear. If the failure surface can be repaired or the die surface can be given a more superior performance, this will significantly improve the die life, save costs and resources. The surface spraying of the composite material can significantly improve the wear resistance of the base material, and the process is also applicable to the mold manufacturing. In recent years, the surface spraying technology has been gradually showing its important role in improving the life of various die and reducing the production costs.Although T10 steel is regarded as a kind of commonly used cold die materials, there is not yet an effective method to improve its useful life at present. In order to find a thermal spraying method which can improve the wear resistance of the cold die steel surface, the WC-10Co-4Cr coatings were deposited on the T10 steel substrate by High Velocity Oxygen Fuel spray process and the Al2O3+13%Ti O2 coatings were prepared on the T10 steel substrate by plasma spray process in this paper. In addition, the microstructure, phase structure of the powders and coatings and interfacial bonding mechanism were analyzed, and the surface roughness, microhardness and friction and wear properties of the coatings were investigated.The two kinds of coatings prepared under the optimal spray process had a well-distributed structure, and the combine between layers and layers was very tight. The combine between coatings and substrate was mainly the mechanical with some metallurgical bonding. After spraying, the surface roughness of the two original coatings could not reach the requirements of the die surface roughness, so the coatings could be used only after the grinding machine processing with the diamond grinding paste. The microhardness of the surface and cross-section of the two coatings was obviously higher than that of T10 steel, and the microhardness of the WC-10Co-4Cr coatings was higher than that of the Al2O3+13%Ti O2 coatings. In oil lubrication and no lubrication friction and wear test, the fluctuation of the friction coefficient in the two coatings was less than that of T10 steel, including the wear process of WC-10Co-4Cr coating was the most stable and the binding performance between WC-10Co-4Cr coating and substrate was significantly better than that of Al2O3+13%Ti O2 coating. The wear depth of WC-10Co-4Cr coating was about 1/3 of that of T10 matrix, and the wear resistance of WC-10Co-4Cr coating was better than that of Al2O3+13%Ti O2 coating. For the wear mechanism, the WC-10Co4 Cr coating exhibited abrasive wear, the T10 matrix was adhesive wear, but the Al2O3+13%Ti O2 coating showed embrittlement fracture and schistose exfoliation. The research results provide an important basis for improving the wear resistance of T10 steel suface.