烧结破碎粉末反应等离子喷涂制备TiN基陶瓷涂层

Reactive plasma sprayed TiN-based ceramic coating prepared with sintered-crushed powders

采用烧结破碎法对Ti和B4C反应喷涂粉末进行了处理。制备的粉末经反应等离子喷涂制备了TiN基陶瓷涂层,并对涂层的微观形貌、物相、显微硬度以及在3.5wt%NaCl溶液中的极化行为进行了分析。结果表明,经900℃真空压块烧结粉末制备的涂层致密,涂层厚度达250μm,显微硬度显著提高。与碳钢相比,TiN基陶瓷涂层在3.5wt%NaCl溶液中自腐蚀电位发生正移,钝化区较宽,在很宽的电位范围内电流密度较低,耐蚀性优异。

Ti and B4C reactive spraying powders were sintered and crushed. TiN-based ceramic coatings were prepared by reactive plasma spraying with the sintered powders. Microstructure, phases, microhardness and polarization behavior in 3.5wt% NaCl solution of the TiN- based ceramic coatings were analyzed. The results show that the coating prepared with powders compacted and sintered in vacuum at 900 ℃ is compact, its thickness is about 250 μm and micro-hardness is enhanced remarkably. Compared with carbon steel, the corrosion potential of the ceramics coating in 3.5wt% NaCl solution is more positive. The passivation zone is board and the current density in passivation zone is lower, and the corrosion resistance of the reactive plasma sprayed coating prepared with compacted and sintered powders is excellent.