Correlations regarding the evolution of the welded structural steels microstructure in relation to welding conditions

Structural steels are widely used in civil and industrial construction, in the transport and energy industries, utilities, heavy industry, etc. Their mechanical properties and their performance in service depend directly on the microstructural characteristics of the welded joints in the deposited metal and in the heat-affected zone (HAZ). The paper presents a series of mathematical models that can be used to simulate the microstructure of the welded joint based on the CCT continuous cooling diagrams and welding parameters. These data can be used to optimize welding procedures in order to increase the quality, mechanical strength and performance of welded joints made of structural steels. These models can integrate correlations proposed by artificial intelligence (AI) and validated based on experimental data from industrial practice.