High-temperature deformation of ESR En 36 steel

Abstract

The mechanical properties of electroslag-refined (ESR) En 36 steel have been studied in the temperature range 1140-1520K and compared with conventionally cast material. The properties included hot workability (hot torsion), and high-temperature tensile and creep properties. The hot ductility in torsion was improved considerably in the ESR material, and the temperature at which peak ductility occurred was 1470K. There were slight improvements in the high-temperature tensile ductility and creep resistance in the ESR steel. The improvements in the mechanical properties have been attributed essentially to the removal of larger non-metallic inclusions and a reduced sulphur content. From the estimated apparent activation energies, 460 kJ/mol for deformation in hot torsion and 270 kJ/mol for tensile and creep deformation, a rate-controlling mechanism of dynamic recrystallization and one based on self-diffusion, respectively, have been identified.