Influence of the scale factor on the constraint effect in welded joints with soft interlayers

Abstract

Abstract The influence of the scale effect on the strength of mechanically inhomogeneous welded structures with a soft zone was studied. The investigated welded samples were made of two 12Kh18N10T austenitic steel plates and a low-carbon ferritic insert connected between them by two dissimilar welded joints performed by electron beam welding. Tensile strength as a function of relative thickness for tensile specimens with a thickness of 1.2 to 10 mm was plotted. It was shown that with a relative thickness of the soft zone in the range from 0.2 to 0.5, the scale effect did not manifest during tension. This can be explained by low plastic compressive deformations in the soft zone after heat treatment, which typically leads to a decrease in the constraint effect due to the Bauschinger effect.