目的 研究影响超音速等离子喷涂 Cr₂O₃ 涂层硬度的主要因素,制备出高硬度涂层。 方法 首先采用单变量法研究超音速等离子生成气体压力( 空气压力) 和喷涂距离对涂层显微结构的影响,然后采用正交试验研究喷涂电流、空气压力、喷涂距离对 Cr₂O₃ 涂层硬度的影响。 结果 工艺参数对 Cr₂O₃涂层硬度影响的主次顺序为:空气压力> 喷涂电流> 喷涂距离。 结论 获得高硬度涂层的最佳工艺参数组合为:空气压力 0 . 4 MPa,喷涂电流 270 A,喷涂距离 200 mm。 在该工艺条件下获得的涂层致密、均匀,孔隙率小。

Objective To prepare coating with high hardness, this paper studied the main factors influencing the hardness of Cr₂O₃ coating. Methods The influences of spraying distance and air pressure on the coating microstructure were studied by single variable method, and then the effects of three factors including spraying current, air pressure and spray distance on the hardness of Cr₂O₃ coating were investigated with orthogonal experiments. Results The results showed that the primary and secondary order of the Cr₂O₃ coating hardness by technical parameters was: air pressure, spray current, and then spraying distance. Conclusion The optimal combination of process parameters for high hardness coating was: air pressure 0. 4 MPa, spraying current 270 A, spraying distance 200 mm. The coating was dense, uniform and with low porosity.