Ni/G含量对TiN-Ni/G复合涂层抗泥浆冲蚀性能的影响

Effect of Ni/G content on the anti-mud erosion performance of TiN-Ni/G composite coatings

摘要:

等离子喷涂涂层中不可避免存在残余应力和微裂纹,为了减少TiN涂层的残余应力,在等离子喷涂TiN涂层中添加了Ni/G,在45#钢表面制备了TiN-Ni/G复合涂层。研究了Ni/G含量对涂层的微观组织、显微硬度以及抗冲蚀性能的影响,并分析了涂层在不同pH值泥浆中的冲蚀机理。结果表明：TiN-Ni/G 复合涂层的平均硬度值在1000HV0.2左右,在5wt.%NaCl 泥浆中涂层冲蚀过程中受到SiO2颗粒的冲击以及溶液的腐蚀；pH=10的NaOH泥浆对涂层冲蚀表现为SiO2冲击作用。涂层在含NaOH泥浆中的质量损失较中性溶液有明显减少,在两种冲蚀液中Ni/G含量为11wt.%时涂层都表现出良好的抗冲蚀性能

Abstract:

Residual stress and microcracks inevitably exist in plasma spraying coatings. In order to reduce the residual stress of the TiN coating prepared by reactive spraying, Ni/G was added to the TiN coating. TiN-Ni/G composite coatings were prepared on the surface of 45# steel. The effects of Ni/G content on the microstructure, microhardness and erosion resistance of the coating were studied, and the erosion mechanism of coatings in slurries with different pH values was analyzed. The results showed that the average hardness of the TiN-Ni/G composite coating was about 1000HV0.2, and coatings were impacted by SiO2 particles and corroded by the solution during the erosion process of the coating in 5wt.%NaCl slurry; the coating was mainly subjected to the impact of SiO2 during the erosion process in the NaOH mud at pH=10, and the mass loss of the coating in NaOH mud was significantly reduced compared with that in the neutral solution. When the Ni/G content is 11wt.%, the coatings show good impact resistance.