The prediction of residual stress and its influence on the mechanical properties of weld joint

Abstract

Abstract.A three-dimensional metallo-thermo-mechanical analysis of bead on plate welding is performed in this work. This coupled model enables to capture the microstructural development and temperature history at local region. As a result, the residual stress is evaluated based on the temperature-dependent mechanical properties computed by the mixture of individual phase. Isotropic hardening is assumed in the finite element (FE) analysis. At the same time, the distribution of residual stress is also predicted by treating the mechanical properties as integral values of sheet metal. The two simulated fields of stress and strain after welding are analysed and compared. Moreover, as it is known that welding changes the mechanical properties of the original material, especially in fusion zone (FZ) and heat affected zone (HAZ), the stress and strain data at interested areas (HAZ and FZ) are subtracted for comparison. The predicted stress and strain fields are imported to subsequent simulation of standard tensile test. The stress-strain curves are compared with the one of base material. It is found that residual stress has significant influence on the structural performance of weld joints.

Life Prediction Method of Dissimilar Lightweight Materials Welded Joints with Precrack under Coupled Impact-Fatigue Loading

“…However, the welding process generates residual stresses and defects such as porosity and incomplete penetration, which are prone to produce macroscopic crack under fatigue or impact loading [ 2 , 3 ]. Therefore, it is important to reveal the fatigue failure mechanism of dissimilar light metal welded joints including initial defects under complex loadings [ 4 , 5 ].…”

Design of welding parameters for laser welding of thick-walled structures made of aluminum alloy

“…It mostly includes coupled thermal, metallurgical, and mechanical analysis [1][2][3][4][5][6]. In modeling and numerical simulation, the influence of the laser beam on the material during the fusion welding process can be defined by means of different heat source models [7][8][9][10][11][12][13][14]. Understanding thermal phenomena and the heat transfer during the welding process is crucial for the analysis of microstructure, mechanical properties, and a quality of the weld joints [15][16][17][18].…”