Characteristic of solute-diffusion bonding between stainless steel and Ni-based micro-crystal powder

Microstructures and properties of liquid film solute-diffusion bonding interface of 0Cr18Ni9Nb stainless steel (SS) was studied.It shows that Ni-based alloy powders with metastable structure can realize the solute-diffusion bonding of 0Cr18Ni9Nb stainless steels.The weld has good connection with base materials and the joint is composed of weld,bonding interface,and near interface base metal zone,of which,bonding interface zone is constructed by two parts:a single phase γ(Ni) layer of 185 μm thick and a poly-phase layer with γ phase and metallic compounds.The weld zone is composed of homogenous and fine equioxed γ(Ni) grains whose mean size is about 50 μm and intergranular (γ(Ni)+Fe4.5Ni8.5B6) eutectic.While the microstructure of γ-matrix in SS near interface shows no remarkable phase transformation.The joint has a tensile strengths up to 280 MPa and a reasonable distribution of hardness,therefore,good matching has been obtained between the weld and the stainless steel.