Heat treatment method and heat treatment device

Abstract

The invention relates to a method and to a device for the heat treatment of a steel component directed specifically at individual zones of the component. In one or more first regions of the steel component a primarily austenitic structure can be set, from which, by quenching, a predominantly martensitic structure can be produced, and in one or more second regions of the steel component there is a predominantly ferritic-pearlitic structure. The steel component is first of all heated in a first furnace to a temperature below the Ac3 temperature, and the steel component is then transferred into a handling station. During the transfer the steel component can cool, and in the handling station, one or more second regions of the steel component are cooled within a residence time t 150 to a final cooling temperature ϑ S , and is then transferred to a second furnace, in which heat is delivered to the steel component. The temperature of the one or more second regions increases again during the residence time t 130 to a temperature below the Ac3 temperature, whilst the temperature of the one or more first regions is heated in the same residence time t 130 to a temperature above the Ac3 temperature.

1 . A method for the heat treatment of a steel component directed specifically at individual zones of the component, wherein in one or more first regions of the steel component a primarily austenitic structure can be set, from which, by quenching, a predominantly martensitic structure can be produced, and in one or more second regions a predominantly ferritic-pearlitic structure can be set, the method comprising:
 first heating the steel component in a first furnace to a temperature below the Ac3 temperature, transferring the steel component to a handling station, wherein the steel component is cooled cool during the transfer, cooling in the handling station the one or more second regions of the steel component within a residence time t 150  to a final cooling temperature ϑS, and transferring the steel component to a second furnace, in which heat is delivered to the steel component, wherein the temperature of the one or more second regions increases again during the residence time t 130  to a temperature below the Ac3 temperature, whilst the temperature of the one or more first regions is heated in the same residence time t 130  to a temperature above the Ac3 temperature.   
     
     
         2 . The method according to  claim 1 , wherein heat supply in the second furnace is achieved via thermal radiation. 
     
     
         3 . The method according to  claim 1 , wherein the one or more second regions of the steel component are blown with a gaseous fluid in the handling station within a residence time t 150  for cooling. 
     
     
         4 . The method according to  claim 3 , wherein the gaseous fluid contains water. 
     
     
         5 . The method according to  claim 1 , wherein the cooling of the one or more second regions of the steel component takes place in the handling station within a residence time t 150  via thermal conduction. 
     
     
         6 . The method according to  claim 5 , wherein the one or more second regions of the steel component are brought into contact with a die in the handling station within a residence time t 150  for cooling, wherein the die has a lower temperature than the second region or regions. 
     
     
         7 . The method according to  claim 1 , wherein the internal temperature ϑ 4  in the second furnace is greater than the Ac3 temperature. 
     
     
         8 . A heat treatment device, including a first furnace for heating a steel component to a temperature below Ac3 temperature, wherein the heat treatment device further includes a handling station and a second furnace, wherein the handling station includes a device for the rapid cooling of one or more second regions of the steel component and the second furnace includes a device for the introduction of heat, with which at least the first region or first regions of the steel component can be heated to a temperature greater than the Ac3 temperature. 
     
     
         9 . The heat treatment device according to  claim 8 , wherein the device for the rapid cooling of one or more second regions of the steel component has a nozzle for blowing the second region or regions of the steel component with a gaseous fluid. 
     
     
         10 . The heat treatment device ( 100 ) according to  claim 8 , wherein the device for the rapid cooling of one or more second regions of the steel component has a nozzle for blowing the second region or regions of the steel component with a gaseous fluid, to which water is added. 
     
     
         11 . The heat treatment device according  claim 8 , wherein the device for the rapid cooling of one or more second regions of the steel component includes dies for contacting the second region or regions of the steel component. 
     
     
         12 . The heat treatment device according to  claim 11 , wherein the die for contacting the one or more second regions of the steel component is executed to be coolable. 
     
     
         13 . The heat treatment device according to  claim 8 , wherein in that the handling station has a positioning device. 
     
     
         14 . The heat treatment device according to  claim 8 , wherein the second furnace is heated to a substantially homogeneous temperature ϑ 4 . 
     
     
         15 . The heat treatment device according to  claim 8 , wherein the handling station includes heat reflectors. 
     
     
         16 . The heat treatment device according to  claim 8 , wherein the handling station includes thermally insulated walls.