Capillary electron beam brazing of stainless steel tube-to-plate joint

Stainless steel capillary tube-to-plate brazed joint by electron beam has been achieved using electron beam brazing system based on Virtual Instruments.Effects of electron beam brazing parameters including beam current,heating time,focus current and scanning amplitude on the quality of brazing joints are discussed.Experimental results show that fillet height and diffusion depth of BNi-2 filler metal to capillary tube wall both increase with electron beam input power density increasing.Penetration rate of the stainless steel tube-to-plate joint is up to 100% and erosion phenomena of capillary tube are not found when optimized processing parameters of electron beam brazing are adopted.Chemical composition of phases at brazed joint is also investigated by an electron probe microanalyser.Brazed joint consists of nickel boride,nickel silicide,chromium boride and solid solution.