Numerical Modeling and Initial Fatigue Life Estimations of Welded Structural Components

Abstract

Numerical simulations are powerful tool for analyzing and research in domain of mechanical constructions. In welded joints is very important to determine residual stresses and temperature distribution in sample, apropos, element of construction. In some cases doing the experiment is not possible, so numerical simulations can give the required results and overview of stress state, residual stresses, critical areas, displacement, temperature distribution and other data is needed for analyzing and improvement of constructions or parts of constructions. This analysis includes finite element model for the thermal and mechanical welding simulation. Welding simulation was considered as a sequential coupled thermo-mechanical analysis. The residual stress distribution and magnitude in axial direction was obtained. The paper also shows the results obtained in a simultaneously test of a butt welded thin steel sheet specimen by conventional methods and thermography. Numerical methods are also used in order to predict the crack of specimen. The obtained results confirm that it is very useful to use thermography and Finite Element Method (FEM) for early diagnostics of the complex structures in the exploitation conditions. In this paper is obtained good agreement of results between experiment and Numerical simulations.