joining AISI304 to A351CF-3M stainless steels with pure copper filler metal in furnace brazing

in this study type 304 stainless steel 304SS was brazed to A351CF-3Mstainless steel A351SS in the furnace using pure copper AWS Bcu-1 as a filler material single lap specimens were prepared various tests were carried out in the temperature ranging between 1105 C -1150C and time varies from 0-20 minutes in argon atmosphere 99.99% the wetting angle between the A351SS and the copper filler metal was less than that between the 304 ss and copper filler metal however the depth of copper diffusion in 304 ss was higher than that in A351 ss due to formation of non coherent interface . the thicknesses of interface in the 304SS and A351SS were 13.1mm and 3.14mm respectively the results show the best brazing temperature and time are 1120c-1135 and 10-15 minutes respectively .microstructures of joint zone were examined by optical and scanning electron microcopy equipped with EDS detector.

Keywords:

brazing , stainless steel , microstructural analysis , shear strength