The microstructure and mechanical properties of powder-forged Fe-C-Cu alloys manufactured at an elevated temperature were evaluated. It was found that the mechanical properties of the alloys were no worse than those in the literature, and the contribution of copper to the strength was quantified: the major strengthening mechanism of copper is grain-refinement strengthening rather than precipitation strengthening. Then, to ensure the safety of the elevated-temperature manufacturing, the hot-deformation behaviour of the Fe-C-2.5Cu alloy was investigated via construction of the constitutive equation and the hot-processing map, which proved that the high-temperature manufacturing was not only safe but also efficient. Finally, fatigue tests were conducted on the powder-forged connecting rods and 5154 wrought steel connecting rods for the same engine application, and the results showed that the powder-forged connecting rods had better fatigue strength and higher reliability.

评价了在高温下制造的粉末锻造Fe-C-Cu合金的显微组织和力学性能。发现合金的机械性能不比文献中的差，并且量化了铜对强度的贡献：铜的主要强化机理是细化强化而不是析出强化。然后，为确保高温制造的安全性，通过本构方程和热加工图的构建，研究了Fe-C-2.5Cu合金的热变形行为，证明了高温制造不仅安全而且高效。最后，