Assessment and comparison of the bearing capacity of a welded joint with a semi-elliptical crack of high-strength steel welded using different welding technologies

Abstract

Assessment of the bearing capacity of the welded joint (all its zones) of high-strength steel has an important role for the safe use of the welded structure. The welded joint represents a key problem due to heterogeneity, mechanical, and operational properties, as well as the presence of a crack-type defects. The behaviour of a welded joint with a crack is unpredictable due to the influence of many factors. To better understand the behaviour of the base material and its welded joint, it is necessary to carry out appropriate tests. This study presents the determination of the bearing capacity of a welded plate (S960MC) with a semi-elliptical crack in the heat affected zone (HAZ), comparing two welding technologies: electron and laser beam. The hardness of the material was measured experimentally and the mechanical properties of the material were determined using correlation equations. Then, as per ASTM E1820 standard for bending the test specimens in three points, the results of the material toughness were obtained. Finally, using all the calculations, the SINTAP method was used to analytically determine the critical forces that would cause the structure to break.