热腐蚀和盐雾腐蚀影响氮化物涂层冲蚀行为的机制

Nitride coatings have been applied and regarded as key erosion resistant coating system for aircraft compressor. In order to consider the effect of thermophysical and chemical environment as well as stress environment, it was important to study the coupling behavior of corrosion and erosion for these nitride coatings. In the present work, the erosion behaviors of original coating, the hot corroded coating and the salt spray corroded coating were compared for both TiN/Ti coating and TiN/ZrN coating. The results show that for TiN/Ti coating, the pittings caused by coating defects are weak regions to erosion. The salt spray corroded TiN/Ti coating has lower adhesion and erosion resistance than original coating and hot corroded coating. For TiN/ZrN coating, loose corrosion and oxide products form on the surface of droplets during hot corrosion, so they are easier to fall off during erosion. Moreover, the generative interlayer thermal stress in hot corrosion process weakens the adhesion between the coating and substrate. The surface of the hot corroded coating shows the most severe spiral peeling after erosion, and the hot corroded TiN/ZrN coating has lower adhesion and erosion resistance than original coating and salt spray corroded coating.