摘要
TiN-matrix composite coating was prepared on 45# steel by reactive high-velocity oxy-fuel （HVOF） spraying. Its microstructure, phase composition, micro-hardness, corrosion resistance in 3.5% NaC1 solution and wear resistance were analyzed. The results suggest that the TiN-matrix composite coating is well bonded with the substrate. The micro-hardness measured decreases with the increase of applied test loads. And the micro-hardness of the coating under heavy loads is relatively high. The TiN-matrix composite coating exhibits an excellent corrosion resistance in 3.5% NaC1 solution. The corrosion potential of coating is positive and the passivation zone is broad, which indicates that the TiN-matrix composite coating is stable in the electrolyte and provides excellent protection to the substrate. The wear coefficient of the coating under all loads maintains at 0.49-0.50. The wear mechanism of the coating is revealed to be three-body abrasive wear. Yet the failure forms of TiN-matrix composite coating under different loads have an obvious difference. The failure form of coating under light loads is particle spallation due to the stress concentration while that of coating under heavy loads is crackin~ between inter-lamellae.
采用反应超音速喷涂方法在45#钢基体上制备TiN基复合涂层,并对涂层的显微结构、相成分、显微硬度和在3.5%NaCl溶液中的腐蚀行为和耐磨性进行研究。结果表明,TiN复合涂层与基体结合良好,在较大载荷下显微硬度较高。TiN基复合涂层的耐蚀性优异,其腐蚀电位较正,钝化区很宽,这表明涂层在电解液中很稳定,有效地保护了基体。磨损实验表明在196、294和735 N的载荷下摩擦因数基本保持在0.49～0.5。磨损机制为三体磨料磨损,轻载荷下的失效形式为应力集中造成的涂层颗粒剥落,而在重载荷下为涂层间的开裂。
基金
Project(KFJJ10-15M) supported by the Open Fund of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,China
Project(E2013208101) supported by the Nature Science Fund of Hebei Province,China
Project(Z2012100) supported by Colleges and Universities Science and Technology Research Fund of Hebei Province,China
Project supported by the Outstanding Youth Fund of Hebei University of Science and Technology,China
