摘要
采用放电等离子烧结技术(SPS)制备铜基石墨复合材料,研究不同烧结温度对铜-石墨复合材料的致密度、维氏硬度、电导率和载流摩擦磨损性能的影响。结果表明:在所制备的铜-石墨复合材料中,石墨均匀分布,铜与石墨界面结合紧密;随着烧结温度的升高,复合材料的致密度、维氏硬度和电导率均升高,但摩擦系数和磨损率均先减小后增大,其中烧结温度为780℃时,摩擦系数和磨损率同时达到最小值;同时,在设定的烧结温度范围内,载流效率和载流稳定性在很小的范围内波动。在设定工况下,载流摩擦损伤机理主要为磨粒磨损,烧结温度在780℃左右时摩擦损伤较轻,烧结温度超过780℃时所制备的材料,磨损时伴有严重电弧烧蚀现象。综合考虑,780℃为制备铜-石墨复合材料的最优烧结温度。
Copper-based graphite composites were fabricated by spark plasma sintering(SPS), and effects of different sintering temperatures on relative density, Vickers hardness, electrical conductivity and current-carrying friction and wear properties of the copper-based graphite composites were studied. The results show that the graphite is uniformly distributed in the copper-graphite composite materials, and the interface between copper and graphite is tightly bonded. With the increase of sintering temperature, the relative density, Vickers hardness, and electrical conductivity of the composites increase, but the friction coefficient and wear rate decrease first and then increase. When the sintering temperature is 780 ℃, the friction coefficient and wear rate reach the minimum. Within the setting sintering temperature, the current-carrying efficiency and current-carrying stability fluctuate in a very small range. Under the setting condition, the wear mechanism of current-carrying friction is mainly abrasive wear. The friction damage of the copper-graphite composite materials is light when sintering temperature is about 780 ℃, and the material prepared above 780 ℃ is accompanied by serious arc ablation phenomenon. Therefore, the optimum sintering temperature of the copper-graphite composites is 780 ℃.
引文
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