Loading patent…
AssigneeThyssenKrupp Automotive AG
InventorsHans Vondracek, Hans DziemBalla, Lutz Manke, Alexander Borowikow, Reinhard Uhrich, Matthias Hüttner
Estimating the term…
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-crystallisation temperature, the structure is austenitised, held at an equalised temperature and then formed and subsequently quenched to form martensite and tempered. Round steel bars, whose re-crystallisation temperature is adjusted over the bar length in a compensation furnace, constitute the parent material. The round steel bars are subsequently re-modelled by cross-rolling, remaining substantially straight and after the critical deformation degree has been exceeded are subjected to dynamic re-crystallisation 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-crystallisation and finally are quenched from the austenitic state to form martensite and tempered.
Method for the thermomechanical treatment of steel, wherein the starting material is heated to a temperature above the recrystallization temperature, austenitized, held for equalization of temperature, then deformed and finally quenched to martensite and tempered, characterized by starting out with round steel rods, the heating temperature of which is equalized over the rod length and which then are transformed by skew rolling, while remaining approximately straight, so that a predetermined twisting of the material in the marginal area and a desired transformation gradient is achieved over the cross section, and wherein, after the critical degree of transformation is exceeded, dynamic recrystallization processes take place, whereupon the rods are reheated to a temperature above Ac3, in order finally to be hardened and tempered.
Dependencies are inferred from the claim text.