28.5.2019 Brazing

Influence of Gap Clearance on Brazing Joint Strength for Ni- and Fe-base Filler Metals for Brazing Ferritic Stainless Steels

Ferritic stainless steels are gaining increasing interest for brazed components due to the combination of low cost, low thermal expansion and good high temperature scaling resistance, compared to the commonly used austenitic stainless steels. As a continuation of our recent work on the effect of gap clearance on joint strength for austenitic stainless steels, the same effect has been studied for ferritic stainless steels. Due to differences in diffusivity of elements in ferritic stainless steels compared to austenitic stainless steels, the data from austenitic stainless steels cannot easily be extrapolated to ferritic stainless steels. In this investigation, AISI 430 butt-joint specimens were brazed with different nominal gap clearances ranging up to 300 μm, and the effect on the joint tensile strength was measured.