Numerical and experimental studies on temperature and distortion patterns in butt-welded plates

A computationally efficient solution is adopted for 3D transient analyses of both thermal and structural responses of steel plates to single-pass gas tungsten arc welding. Considering the temperature-varying thermal and mechanical properties of the steel material, the temperature distribution in the plate calculated by the numerical approach turned out to have a good agreement with the experimental results of butt welding tests. The structural response of welded plates including the residual stress and deformation has also been studied. The numerical results generally agree well with the experimental measurements. The effect of the Element Birth-Death technique has been discussed in detail, considering the double ellipsoidal moving heat source. The magnitude of peak temperature in the plates is found 8.76 % higher when taking into account the Element Birth-Death effect. The effects of finite element mesh size and convection coefficient on the simulation result have been discussed. The convection coefficient has a very low effect on the maximum temperature but is critical to the temperature gradient in the cooling stage.