Steel and processing method for the manufacture of high strength, fracture-splittable machinery components

Abstract

The invention relates to a steel and a processing method for high-strength fracture-splittable machine components that are composed of at least two fracture-splittable parts. The steel and method are characterized in that the chemical composition of the steel (expressed in percent by weight) is as follows: 0.40%≦C≦0.60%; 0.20%≦Si≦1.00%; 0.50%≦Mn≦1.50%; 0%≦Cr≦1.00%; 0%≦Ni≦0.50%; 0%≦Mo≦0.20%; 0%≦Nb≦0.050%; 0%≦V≦0.30%; 0%≦Al≦0.05%; 0.005%≦N≦0.020%, the rest being composed of iron and smelting-related impurities and residual matter.

1 . A steel and the processing method for the manufacture of high strength, fracture-splittable machinery components, wherein they consist of at least two fracture-splittable parts, wherein their chemical composition has the following components in percentages by weight:
 0.40%≦C≦0.60%   0.20%≦Si≦1.00%   0.50%≦Mn≦1.50%   0%≦Cr≦1.00%   0%≦Ni≦0.50%   0%≦Mo≦0.20%   0%≦Nb≦0.050%   0%≦V≦0.30%   0%≦Al≦0.05%   0.005%≦N≦0.020%   whereby the remainder consists of iron and impurities from the melting process and residues.   
   
   
       2 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.10%≦V≦0.20%   
   
   
       3 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.020%≦Nb≦0.030%   
   
   
       4 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.010%≦N≦0.020%   
   
   
       5 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.45%≦C≦0.55%   0.50%≦Si≦0.70%   0.90%≦Mn≦1.10%   0.10%≦Cr≦0.40%   0.10%≦Ni≦0.30%   0.10%≦V≦0.20%   0.010%≦Al≦0.020%   0.020%≦Nb≦0.030%   0.010%≦N≦0.020%   
   
   
       6 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.45%≦C≦0.55%   0.50%≦Si≦0.70%   0.90%≦Mn≦1.10%   0.10%≦Cr≦0.40%   0.10%≦Ni≦0.30%   0.10%≦V≦0.20%   0.010%≦Al≦0.020%   0.020%≦Nb≦0.030%   0.010%≦N≦0.020%   0.020%≦Ti≦0.030%   
   
   
       7 . A steel in accordance with  claim 1 , wherein its chemical composition is the same except that:
 0.45%≦C≦0.55%   0.50%≦Si≦0.70%   0.90%≦Mn≦1.10%   0.30%≦Cr≦0.40%   0%≦Ni≦0.20%   0.10%≦V≦0.20%   0.010%≦Al≦0.020%   0.020%≦Nb≦0.030%   0.015%≦N≦0.020%   
   
   
       8 . The use of a steel in accordance with  claim 1  to manufacture fracture-splittable components used in the construction of vehicles, whereby they have a predominantly pearlitic structure from the precipitation of special carbides after forging and controlled cooling. 
   
   
       9 . A component in accordance with  claim 8 , wherein the apparent limit of elasticity is over 750 N/mm 2  after cooling down from the forming temperature. 
   
   
       10 . A component in accordance with  claim 9 , wherein the tensile strength falls between 950 N/mm 2  and 1200 N/mm 2  after cooling down from the forming temperature. 
   
   
       11 . A component in accordance with  claim 10 , wherein the elongation to fracture exceeds 10% after cooling down from the forming temperature. 
   
   
       12 . A component in accordance with  claim 11 , wherein the reduction in area at fracture exceeds 25% after cooling down from the forming temperature. 
   
   
       13 . A component in accordance with  claim 12 , wherein it is fracture splittable. 
   
   
       14 . A component in accordance with  claim 13 , wherein it is suitable for induction hardening. 
   
   
       15 . A component in accordance with  claim 14 , wherein the mechanical properties can be adjusted both in the material prior to forging as well as in the component through the use of thermomechanical treatment.