Stress state and the static strength of mechanically inhomogenous welded joints. Report 2. Effect of a small degree of mechanical inhomogeneity on the strength of butt welded joints

The characteristics of the stress state in the presence of a small amount of mechanical inhomogeneity (k_u<2) have been uncovered for welded joints containing a soft interlayer. An approach has been developed for estimating the weight carrying ability of these joints. The association of the contact tangential stresses with the basic structural-geometric parameters of a welded joint (k_u, k) under conditions of plane strain has been established based on the mathematical theory of plasticity. More accurate formulas describing the stress tensor components and the mean stresses during ductile failure have been presented. These formula are in good agreement with the experimental data. In assuming an equilibrium distribution of the strength characteristics over the volume of the soft interlayer, expressions were obtained which can be used at the design stage for choosing the optimum parameters for the welded joint, thus increasing its reliability.Translated from Problemy Prochnosti, No. 4, pp. 35–38, April, 1991.