Mechanical Properties of Weld Joints of High-Strength Steel under Dynamic Loading

摘要

The paper represents a computational model for predicting the mechanical behavior of welded joints in steel constructions under dynamic load, taking into account the change in the properties of the steel in the welding zone. Plastic deformation localization and formation of cracks in welded joints subjected to tensile loading have been studied numerically. Numerical modeling confirms that the model proposed in the work can predict the strength and mechanical behavior of welded joints in steel constructions in a wide range of strain rates, taking into account the phase and granular structure in the weld area. The results confirm that residual stresses of ∼ 100–150 MPa do not significantly affect the formation of the fracture zone in arc welded joints of 09G2S steel subjected to dynamic loading. Fracture of considered welded joints exhibits ductile behavior at initial temperature of 295K and high strain rates. The results have shown that mesoscopic cracks nucleate in the heat-affected zone at effective strains above 12%.