Alloyed cast steel and article made therefrom

Abstract

Disclosed is structural low-alloy manganese cast steel having increased hardness and wear resistance, and an article made therefrom. In particular, after carrying out conventional bulk hardening followed by tempering, the disclosed steel has hardness of approximately 418 to 512 HB and is suitable for use in railway engineering, in particular for manufacturing parts of freight car trucks such as a friction wedge. Due to improved hardness and wear resistance of the parts made of the steel according to the present invention, an increase in inter-repair service life, in particular, of the friction wedge/friction plate friction pair is provided without a significant increase in cost for the parts.

1 . Alloyed case steel characterized by the following content of elements (wt. %): 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   Carbon (C) 
                   0.27 to 0.35 
                 
                     
                   Manganese (Mn) 
                   1.20 to 1.40 
                 
                     
                   Silicon (Si) 
                   0.60 to 0.80 
                 
                     
                   Chromium (Cr) 
                   0.10 to 0.25 
                 
                     
                   Aluminium (Al) 
                   0.02 to 0.05 
                 
                     
                   Vanadium (V) 
                   0.015 to 0.040 
                 
                     
                   Phosphorus (P) 
                   no more than 0.030 
                 
                     
                   Sulfur (S) 
                   no more than 0.030 
                 
                     
                   Nickel (Ni) 
                   no more than 0.30 
                 
                     
                   Copper (Cu) 
                   no more than 0.30 
                 
                     
                   Molybdenum (Mo) 
                   no more than 0.08 
                 
                     
                   Iron (Fe) 
                   the remainder 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
         wherein the complex alloying coefficient CE for said steel calculated as
   CE=C+(Mn+Si)/6+(Cr+Mo+V)/5+(Ni+Cu)/15 
 
         is no less than 0.68% wt. 
       
     
     
         2 . Alloyed cast steel according to  claim 1 , characterized in that its hardness after bulk hardening followed by tempering ranges from 418 to 512 HB. 
     
     
         3 . An article made of the steel according to  claim 1  by casting. 
     
     
         4 . The article according to  claim 3 , characterized in that the article made of the alloyed cast steel is a friction wedge of a freight car truck. 
     
     
         5 . An article made of steel according to  claim 2  by casting.