突破常规铁基粉末合金的制备工艺，设计出一种制备高密度Fe-Cu-C合金的新工艺.通过对铁粉表面进行硫化处理，Fe与S反应合成FeS，均匀包覆在Fe粉颗粒表面，形成一层FeS润滑薄膜，有利于降低压制摩擦力.通过X射线衍射、扫描电镜、和场发射扫描电镜分析研究材料的物相、元素分布和显微组织.研究结果表明：包覆在铁粉颗粒表面的FeS薄膜，有利于提高压坯密度，活化烧结.当S质量分数为0.5%时，硫化处理的Fe-2Cu-0.8C合金的力学性能优异，压坯密度7.31 g·cm-3，硬度78.6 HRB，抗拉强度485 MPa；当S质量分数达到0.8%时，多余的FeS占压制体积分数，导致试样的压坯密度降低，力学性能降低.
Breaking through the conventional P/M processing, a new process for preparing high density Fe-Cu-C alloys was designed. Through sulfuring treatments on the surface of iron powder, Fe reacts with moderate S to generate FeS, which is uniformly coated on the surface of iron powder particles and formed a thin-layered FeS lubrication film. The FeS lubrication film is useful for reducing the friction of compaction. The phase, element distribution and microstructure were characterized by X-ray diffraction, scanning electron microscopy and field emission scanning electron microscopy. The results show that the FeS lubrication film coating on the surface of iron powder is significant to improve the green density and activate sintering. After sulfuring treatments, Fe-2Cu-0.8C alloys with 0.5% S exhibit higher mechanical properties:the green density reaches 7.31 g·cm-3, the hardness 78.6 HRB, and the tensile strength 485 MPa. When the mass fraction of S is 0.8%, redundant FeS accounts for pressing volume fraction, resulting in the decreasing of green density and mechanical properties.