Process for producing tempered steel motor vehicle parts

Abstract

A process for production of tempered steel support structures for motor vehicles of multiple steel parts including the steps deforming and/or trimming at least two soft-hardened steel parts, hardening the at least two steel parts, joining the steel parts to form a support structure, wherein the support structure is subject to annealing and total stress relieving in a combined thermal treatment only after the joining step.

1 . A process for production of tempered steel support structures for motor vehicles of multiple steel parts including the steps 
 deforming and/or trimming at least two soft-annealed steel parts,    hardening the at least two steel parts,    joining the steel parts to form a support structure,    wherein an annealing and total stress relieving of the steel parts in the shape of the support structure is carried out in a combined thermal treatment only after joining.    
     
     
         2 . A process according to  claim 1 , wherein the combined thermal treatment is carried out in a temperature range of from 550 to 690° C.  
     
     
         3 . A process according to  claim 1 , wherein the combined thermal treatment is carried out in a temperature range of 570 to 650° C.  
     
     
         4 . A process according to  claim 1 , wherein the hardening is air hardening.  
     
     
         5 . A process according to  claim 1 , wherein the joining is by welding.  
     
     
         6 . A process according to  claim 1 , wherein the support structure is galvanized following the combined thermal treatment.  
     
     
         7 . A process according to  claim 1 , wherein the support structure is cathartically dip coated (KTL) following the combined thermal treatment.  
     
     
         8 . A process according to  claim 1 , wherein at least one sheet-shaped and one tubular-shaped steel part are employed.  
     
     
         9 . A process according to  claim 1 , wherein at least two steel parts of different thickness are employed.  
     
     
         10 . A process according to  claim 1 , wherein joining parts and/or joining means for securing of other components to the support structure are affixed to the support structure prior to the combined thermal treatment.  
     
     
         11 . A process according to  claim 8 , wherein the joining parts are screws, rivets or nuts and the joining means are bore holes, screw-in sleeve sockets or folds or creases.  
     
     
         12 . A process according to  claim 1 , wherein the steel parts are alloyed steel.  
     
     
         13 . A process for production of tempered steel support structures for motor vehicles of multiple steel parts including the steps 
 deforming and/or trimming at least two soft-annealed steel parts,    air hardening the at least two steel parts,    joining the air hardened steel parts to form a support structure,    annealing and total stress relieving the support structure in a combined thermal treatment after joining, and    galvanizing the support structure subsequent to the combined thermal treatment.