Abstract In powder metallurgy, a high-cost method that is widely used to increase the useful life of the mechanical components is the addition of alloying elements. A less-exploited process is surface enrichment by plasma, where the same result is obtained only on the surface of the component at a rather lower cost. This paper reports on the improvement of the tribological properties of powder injection molding (PIM) self-lubricating composites produced by surface Mo-enrichment. The tribological properties were evaluated in terms of the scuffing resistance, friction coefficient, and wear rate values of enriched and non-enriched specimens, and counter-bodies. Scanning electron microscopy with energy dispersive X-ray spectroscopy and μRaman spectroscopy were used to characterize the wear scars. The results showed that Mo enrichment increased the scuffing resistance by an impressive 2000%, with a 90% decrease in the wear rate of the specimens and counter-bodies. These results were ascribed to several factors, including the microstructural modification, hardness increase, and tribolayer formation.

中文翻译：

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表面富钼烧结自润滑复合材料摩擦学性能的改善

摘要 在粉末冶金中，添加合金元素是一种被广泛采用的提高机械部件使用寿命的高成本方法。一种较少使用的工艺是通过等离子体进行表面富集，其中仅在部件表面以相当低的成本获得相同的结果。本文报道了通过表面钼富集生产的粉末注射成型 (PIM) 自润滑复合材料的摩擦学性能的改进。根据富集和非富集样本以及反体的耐划伤性、摩擦系数和磨损率值评估摩擦学性能。使用具有能量色散 X 射线光谱和μ拉曼光谱的扫描电子显微镜来表征磨痕。结果表明，Mo 富集使耐磨性提高了 2000%，同时试样和反体的磨损率降低了 90%。这些结果归因于几个因素，包括微观结构改性、硬度增加和摩擦层形成。