Technical specifications for hot-rolled thermomechanically processed weldable fine-grain structural steels

This specification defines the delivery conditions for hot-rolled structural steels produced through thermomechanical rolling, a controlled process combining precise temperature schedules and continuous deformation. This manufacturing technique refines the steel microstructure, enabling the attainment of high yield and ultimate tensile strengths with lower carbon equivalent values compared to normalized equivalents. The fine-grain structure provides favorable weldability. Depending on the used thickness this may minimize or eliminate the necessity for preheating prior to welding operations. The standard prescribes strict parameters for yield strength, tensile strength, and impact energy at designated test temperatures.