KUBIAK Marcin Czestochowa University of Technology

Spoluautoři PIEKARSKA Wiesława, SATERNUS Zbigniew, DOMAŃSKI Tomasz, STANO Sebastian

Numerical analysis of the distortion of welded joints is very important at the initial stage of the design, in terms of the quality and the durability of welded constructions. Mathematical and numerical model of coupled thermal, structural and mechanical phenomena should allow the execution of a comprehensive analysis taking into account phase transformations during material’s state changes, phase transformations in solid state and the influence of structural strain on the deformation of welded joints. This work concerns numerical simulations of laser beam butt-welding of modern T-beam constructions I-core type, made of S355 steel. Numerical analysis of thermomechanical phenomena is performed in ABAQUS FEA engineering software. Additional, author’s subroutines are implemented in designed three dimensional models using Fortran programming language. Developed subroutines describe the distribution of volumetric laser beam heat source power, the kinetics of phase transformations in solid state as well as isotropic strain generated by the temperature field and structural strain during heating and cooling of welded steel. Performed computational model takes into account thermomechanical properties of S355 steel changing with temperature. In order to verify the results of numerical simulations real butt-welded T-joints are executed on Yb:YAG laser. Characteristic zones of the cross section of the joint are compared to numerically predicted geometry of fusion zone and heat affected zone. Moreover, numerically predicted transverse and longitudinal displacement in the joint is compared to real displacement, measured using profilographometer New Form Talysurf 2D/3D 120.