Evading Strength-plasticity Conflict in Microstructure-optimized Fe-Cu-Ni-P Sintered Alloy via Layered-composite Powder

Abstract To acquire the improved mechanical properties of engineering sintered alloys, optimizing their internal grain boundaries through tuning powder characteristics is a sophisticated practice. Here a creative element-doping in powder mixture method is reported based on deposition reactions, to obtain novel Fe-Cu-(Ni+P) triple-layered composite powder. A multi-phase microstructure with in-situ γ-(Cu,Fe,Ni) interfacial phase as a grain boundary reinforcement is developed in the as-sintered Fe-Cu-Ni-P alloy, attaining a better yield strength (1538MPa) and plasticity (23.3%) combination. This investigation is a successful demonstration of applying the layered-composite powder to overcome the strength-plasticity trade-off dilemma in sintered materials.