Method for Producing a Component Having Improved Elongation at Break Properties

Abstract

The invention relates to a process for producing a component having improved elongation at break properties, in which a component ( 6 ) is firstly produced, preferably in a hot forming or press curing process ( 4 ), and the component ( 6 ) is heat treated after hot forming and/or press curing ( 4 ), where the heat treatment temperature T and the heat treatment time t essentially satisfy the numerical relationship T≧900·T −0.087 , where the heat treatment temperature T is in ° C. and the heat treatment time t is in seconds. The invention also relates to a component, in particular an automobile body component or the chassis of a motor vehicle, which has been produced by such a process. The invention further relates to the use of such a component as part of an automobile body or a chassis of a motor vehicle.

1 . Method for manufacturing a component with improved elongation at break properties, comprising: producing a component ( 6 ) that is firstly produced, by one of a hot forming and press curing process ( 4 ), and in which the component ( 6 ) is tempered after one of hot forming and press curing ( 4 ) characterised in that the tempering temperature T and the tempering time t substantially satisfy the numerical relationship T≧900·t −0.087 , wherein the tempering temperature T is to be expressed in ° C. and the tempering time t in seconds. 
     
     
         2 . Method according to  claim 1 ,
 characterised in that   the tempering temperature T is lower than the AC 1  temperature, in particular lower than 700° C.   
     
     
         3 . Method according to  claim 1 ,
 characterised in that   the tempering time at a tempering temperature of approximately 500° C. is at least 20 minutes, at a tempering temperature of approximately 550° C. at least 5 minutes, and at a tempering temperature of approximately 600° C. at least 3 minutes.   
     
     
         4 . Method according to  claim 1 ,
 characterised in that   the tempering temperature is at least 500°, preferably 550° C., in particular 600° C. and the tempering time is selected to be high enough that the elongation at break value A 80  of the component ( 10 ) is increased by approximately 15%, in particular by approximately 20%, preferably by approximately 25%.   
     
     
         5 . Method according to  claim 1 ,
 characterised in that   the component ( 6 ,  10 ) substantially consists of a manganese-boron steel, in particular a manganese-boron tempering steel, preferably a 22MnB5 tempering steel.   
     
     
         6 . Method according to  claim 1 ,
 characterised in that   the component ( 6 ,  10 ) is coated or uncoated.   
     
     
         7 . Method according to  claim 1 ,
 characterised in that   prior to tempering, the component ( 6 ) is coated with an inorganic, an organic and/or an inorganic-organic coating.   
     
     
         8 . Method according to  claim 1 ,
 characterised in that   the component ( 6 ,  10 ) is coated with a corrosion protection coating.   
     
     
         9 . Method according to  claim 1 ,
 characterised in that   prior to tempering, the component ( 6 ) is coated electrolytically and/or by hot-dip processing.   
     
     
         10 . Method according to  claim 1 ,
 characterised in that   the component ( 6 ,  10 ) is a body part or a chassis of a motor vehicle.   
     
     
         11 . A component, produced by one of a hot forming and press curing process ( 4 ), and in which the component ( 6 ) is tempered after one of hot forming and press curing ( 4 ), the tempering temperature T and the tempering time t substantially satisfy the numerical relationship T≧900·t −0.087 , wherein the tempering temperature T is to be expressed in ° C. and the tempering time t in seconds, comprising a component that has a tensile strength Rm of 700-1100 MPa, a yield point Rp0.2 of 750-1000 and an elongation at break value A 80  of more than 6%. 
     
     
         12 . Component according to  claim 11 ,
 characterised in that   in the event of a crash, the component ( 10 ) is subjected to a tensile loading.   
     
     
         13 . Component according to  claim 11 ,
 characterised in that   the component ( 10 ) is a side rail ( 32 ,  34 ) of a vehicle frame ( 30 ).   
     
     
         14 . The component of  claim 11 , wherein the component is incorporated into a body or chassis of a motor vehicle.