Effect of carbusintering on densification behavior and mechanical properties of Fe–2%Ni–x%Cu alloys

Densification behavior and mechanical properties of Fe–Ni–Cu alloys prepared by carbusintering (CBS) and conventional sintering (CS) were studied. Carbusintering process showed the improved properties and high density compared with conventional sintering process. These differences can be explained by the microstructure and the diffusion of copper in iron powder. Microstructure observations indicated that the carbusintering process favored to refine grain size. Diffusion model analysis indicated that the diffusion coefficient of copper in iron was up to 0.63 × 10−14 m2/s during carbusintering process. After heat treatment, the hardness, impact energy and ultimate fracture strength of carbusintered compact are increased to 48HRC (484 HV), 13 J and 531 MPa, respectively. The use of CBS process was able to make process simple by taking sintering and carburizing as one step. The higher carbon content of the surface in P/M parts can be easily achieved compared to conventional carburizing.

► A novel process that takes sintering and carburizing as one step is proposed. ► A diffusion model based on specially designed compact with copper wire is proposed. ► Compared to CS, densification and mechanical properties of CBS are improved.