Analytical model of stress field in submerged arc welding butt joint with thorough penetration

Abstract

Abstract. Analytical model of temporary and residual stresses for butt welding with thorough penetration was described assuming planar section hypothesis and using integral equations of stress equilibrium of the bar and simple Hooke's law. In solution the effect of phase transformations (structure changes and structural strains) has been taken into account. Phase transformations during heating are limited by temperature values at the beginning and at the end of austenitic transformation, depending on chemical composition of steel while the progress of phase transformations during cooling is determined on the basis of TTT-welding diagram. Temperature values at the beginning and at the end of transformation are conditioned by the speed of heating. Kinetics of diffusional transformation is described basing on Johnson-MehlAvrami-Kolmogorov equation, while martensitic transformation, basing on KoistinenMarburger equation. Stresses in elasto-plastic state are determined by iteration, using elastic solutions method with changeable longitudinal modulus of elasticity, conditioned by stress-strain curve. Computations of stress field have been conducted for one-side butt welded of two steel flats made from S235 steel. It has enabled a clear interpretation of influence of temperature field and phase transformation on stresses caused by welding using Submerged Arc Welding (SAW) method.

Analytical Model for Distortion Prediction in Wire + Arc Additive Manufacturing

“…The stress gradient, which drops linearly towards the top of the wall can be calculated using Eq. (10).…”

“…This makes it time consuming to compare cross-sectional variations. Analytical approaches, as they exist for buttwelding [10] or cladding processes [11], can estimate distortion fast and effortless. Colegrove et al [2] proposed the analogy of the behaviour of residual stresses in WAAM and bending distortion according to cantilever beam theory, which will be elaborated and validated in this paper.…”