Joining of two materials by powder injection moulding

Abstract

Joining of components of cylindrical shape made of two materials chosen from Fe2Ni, 316L and M2 steels and manufactured by powder injection moulding (PIM) are studied in this paper. In general, joining of PIM cylindrical components requires that the to be joined outer part has a bigger shrinkage than the inner part during sintering. The sintered composite part consisting of Fe2Ni as outer layer and 316L as inner layer is a good example satisfying the above condition. Although the shrinkage of 316L and M2 are less than that of Fe2Ni, the composite parts with Fe2Ni as inner layer and 316L or M2 as outer layer can be successfully produced when different pretreatments are applied to Fe2Ni. Perfect diffusion joining without detectable pores in the vicinity of the bonding area is formed in Fe2Ni-1(or Fe2Ni-2)/316L(or M2) components. Diffusion of Cr and Ni elements has been verified by EDX analysis and it is shown that the diffusion accounts for the hardness of the transition zone.