Review article

The article considers the main factors affecting the micro-structure and mechanical properties of welded joints, the initial condition of welding billets, the chemical composition of structural steels, the structural and phase transformations of metal in the melting and crystallization process. It is shown that the strongest influence on formation of the welded joint and the welding zone adjacent with the overheating zone is imposed by various welding conditions and the initial structural condition of the welded steel. To evaluate the influence of the initial structure of welded billets, there were selected structural steels 08ps, 10, 20, St3, 09G2S and 10ХСНД, which had undergone preliminary thermal and thermal-cycling processing. Welded samples for subsequent structural, mechanical and corrosion tests have been manufactured.