超音速等离子喷涂Al-35Si-4Fe涂层制备工艺优化及摩擦学性能

为改善铝硅合金的摩擦学性能,以YL113铝硅合金为基体,喷涂功率、总气流量和喷涂距离为试验因素,显微硬度和孔隙率为考核指标,采用三因素三水平的正交试验法得到了超音速等离子喷涂Al-35Si-4Fe涂层的最佳制备工艺；研究了此工艺下涂层的摩擦学性能。结果表明：喷涂功率为65 kW,总气流量为110 L/min,喷涂距离为95 mm时,涂层质量为最佳。此时,Al-35Si-4Fe涂层的显微硬度达到465±24.4 HV0.2,涂层孔隙率为1.3%。实验条件下,Al-35Si-4Fe涂层的磨损机制以疲劳磨损为主,磨粒磨损为辅。Al-35Si-4Fe涂层的磨损率为1.88 ×10-4 ^mm3^/Nm,摩擦因数为0.37。优化后的Al-35Si-4Fe涂层能有效保护内部YL113铝硅合金,延长其使用寿命,并应对更加复杂的工况。

Optimization of preparation process and tribological properties of Al-35Si-4Fe coating prepared by supersonic plasma spraying

To improve the tribological properties of Al-Si alloy, YL113 Al-Si alloy was used as the substrate, with spraying power, total gas flow rate, and spraying distance as experimental factors, microhardness and porosity as assessment indicators. The optimal preparation process of supersonic plasma spraying Al-35Si-4Fe coating was obtained using a three factor and three level orthogonal experimental method, studied the tribological properties of the coating under this process. The results show that the coating quality is optimal when the spraying power is 65 kW, the total air flow rate is 110 L/min, and the spraying distance is 95 mm. At this point, the microhardness of the Al-35Si-4Fe coating reaches 465±24.4 HV0.2, and the porosity of the coating is 1.3%. Under experimental conditions, the wear mechanism of Al-35Si-4Fe coating is mainly fatigue wear, supplemented by abrasive wear. The wear rate of Al-35Si-4Fe coating is 1.88×10-4 ^mm3/Nm, and the friction coefficient is 0.37. The optimized Al-35Si-4Fe coating can effectively protect the internal YL113 Al-Si alloy, extend its service life, and cope with more complex working conditions.