Effect of molybdenum additives on the mechanical properties of iron-copper pseudoalloys

The effect of molybdenum additives (10%) on mechanical properties and the microstructure of iron-copper (Fe-30% Cu) pseudoalloys is investigated. The tensile strength, hardness, and electrical resistivity are determined, and the microstructure of specimens is analyzed quantitatively. It is established that during both solid-and liquid-phase sintering, no solid-phase solutions are formed, and a stable heterophase microstructure develops as the components undergo mutual diffusion. The heterophase nature of structure hinders grain growth of the refractory phase. The grain size of the sintered specimens does not exceed 1–5 µm. The plasticity of Fe-30% Cu-10% Mo pseudoalloys obtained during solid-phase sintering is increased significantly as compared with Fe-Cu alloys, and the elongation is 13.8% at a porosity of about 1%. Specimens produced by liquid-phase sintering experience greater elongation, but during prolonged liquid-phase sintering (more than 10 min), grain growth is restored, and the plasticity of the Fe-Cu-Mo specimens is reduced.