Patent attributes
The invention relates to a method for the thermomechanical treatment of steel. According to said method, the parent material is heated to a temperature in excess of the re-crystallization temperature, the structure is austenitized, held at an equalized temperature and then formed and subsequently quenched to form martensite and tempered. Round steel bars, whose re-crystallization temperature is adjusted over the bar length in a compensation furnace, constitute the parent material. The round steel bars are subsequently re-modeled by cross-rolling, remaining substantially straight and after the critical deformation degree has been exceeded are subjected to dynamic re-crystallization processes. The round steel bars are then subjected to a post-heating process above the Ac3 temperature, in order to undergo a complete static re-crystallization and finally are quenched from the austenitic state to form martensite and tempered.