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Solid particle erosion wear (SPE) is one of the important failure modes of the turbine blades, the plating on the surface of the turbine blade material is the primary means to improve the material erosion resistance. In this paper, the multi-arc ion plating method of 2Cr10MoVNbN steel surface modification of the Organization of CrNx coating and focuses on the resistance of the coating and the base metal SPE performance. Analysis results for: surface-to-film-based interface phase composition, coating CrNx turn CRN Cr2N Cr, Cr2N Cr and Cr2N Cr Fe-Cr (solid solution body); plating dense, small defects, the coating and substrate combination of good; coating surface droplet projection, the particles of the coating in the presence of elemental Cr. Typical plastic material erosion wear characteristics, base metal 2Cr10MoVNbN steel reached the maximum erosion rate erosion angle of about 22 °; The coating has CrNx typical erosive wear characteristics of brittle materials, erosion wear rate of erosion angle reaches a maximum of 90 °. The greater the speed, the greater the rate of erosion wear. ANSYS / LS-DYNA finite element simulation and surface morphology analysis, the erosion wear mechanism of the two materials. \cut off, and therefore more severe erosive wear. High angle conditions, materials, mainly plastic deformation, repeated impact of the particles, the material plastic deformation capacity is exhausted, the final surface fatigue spalling. CrNx plating at low angles there are still traces of cutting, but the hardness of the coating is relatively large, uniform, dense, less defects, cutting only slight traces in the defect site and Cr droplet shedding parts the flaking and Cr droplet pulled out phenomenon. High angle conditions, the particles impact the surface of the coating, the local stress concentration generated in the surface, and the stress concentration along the interlayer expansion, the repeated impact of particles, cracks are connected together, coating flaking occurs. Experiments found that of the base metal and the resistance of the coating CrNx SPE: CrNx coating resistance to high temperature solid particle erosion wear performance is much larger than the base metal, speed of 210m / s, erosion angle of 18 °, base metal erosion wear rate is the coating CrNx 400 times, 90 ° when compared with about 27 times. Preform erosion wear rate is about 400 times CrNx plating speed of 420m / s, erosion angle of 18 °, 90 ° when compared to about 3.0 times. At the same time, often used with turbine protective layer boride layer erosion wear test results and mechanical properties are compared, regardless of 18 ° erosion angle or 90 ° erosion angle, boride layer erosion wear rate must be greater than CrNx for anti-solid particle erosion wear performance is better than the boride layer. Both hardness similar to the fracture toughness of the CrNx coating better than the boride layer. In Therefore, coating CrNx is an ideal solid particle erosion of turbine blade material anti-wear protection layer.
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