The characteristic evaluation of brazing joint according to the Ni plating to one-side of the base metal

Vacuum interrupters (VIs) as the most important part of a vacuum circuit breaker play a role to interrupt the fault current by rapidly extinguishing the arc. VIs has been manufactured by the vacuum brazing of a various of materials such as a stainless steel-stainless steel, stainless steel-copper, stainless steel-ceramic, etc. It has been reported by existing studies that wettability and flowability are improved by the Ni plating on a stainless steel surface in brazing of a stainless steel-stainless steel. In this research, in brazing of a stainless steel-stainless steel using AgCu filler metal we performed the Ni plating to only one-side of the base metal, and then observed the microstructure of joints and the melting properties of the base metal according to the brazing time. Additionally, the mechanical properties of the bonded specimens were measured by a tensile strength test and the composition of an image of joints were investigated by SEM and EDS analysis.