Railroad steels having improved resistance to rolling contact fatigue

Abstract

Steels having a pearlitic structure and containing 0.6 to 0.8 wt. % carbon; 0.70 to 1.00 wt. % silicon and 0.8 to 1.2 wt. % manganese can be further alloyed with chromium, molybdenum, vanadium, niobium and/or copper and used to make railway wheels, railway rims and railway rails that are particularly resistant to rolling contact fatigue and, hence, shelling.

1 . A railroad steel having a pearlitic structure and comprised of:
 0.60 to 0.80 wt. % carbon;   0.70 to 1.00 wt. % silicon;   0.80 to 1.20 wt. % manganese;   0.10 to 0.30 wt. % chromium;   0.05 to 0.10 wt. % niobium;   0.00 to 0.10 wt. molybdenum;   0.00 to 0.10 wt. % vanadium;   0.00 to 0.30 wt. % copper;   
     with the balance being iron and incidental impurities. 
   
   
       2 . The railroad steel of  claim 1  having a Brinell hardness between 363 and 400. 
   
   
       3 . The railroad steel of  claim 1  having rolling contact fatigue resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       4 . The railroad steel of  claim 1  having thermal cracking resistance at least equal to that of MR Grade C railroad wheel steel. 
   
   
       5 . The railroad steel of  claim 1  having a strength at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       6 - 10 . (canceled) 
   
   
       11 . A railroad steel having a pearlitic structure and comprised of:
 0.60 to 0.80 wt. % carbon;   0.70 to 1.00 wt. % silicon;   0.80 to 1.20 wt. % manganese;   0.01 to 0.30 wt. % chromium;   0.01 to 0.10 wt. % niobium;   0.20 to 0.30 wt. % vanadium;   0.10 to 0.30 wt. % copper;   
     with the balance being iron and incidental impurities. 
   
   
       12 . The railroad steel of  claim 11  having a Brinell hardness between 363 and 400. 
   
   
       13 . The railroad steel of  claim 11  having rolling contact fatigue resistance at least equal to that of MR Grade C railroad wheel steel. 
   
   
       14 . The railroad steel of  claim 11  having thermal cracking resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       15 . The railroad steel of  claim 11  having a strength at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       16 . A railroad wheel made of a steel having a pearlitic structure and comprised of:
 0.60 to 0.80 wt. % carbon;   0.70 to 1.00 wt. % silicon;   0.80 to 1.20 wt. % manganese;   0.10 to 0.30 wt. % chromium;   0.05 to 0.10 wt. % niobium;   0.00 to 0.10 wt. % molybdenum;   0.00 to 0.10 wt. % vanadium;   0.10 to 0.30 wt. % copper;   
     with the balance being iron and incidental impurities. 
   
   
       17 . The railroad wheel of  claim 16  having a Brinell hardness between 363 and 400. 
   
   
       18 . The railroad wheel of  claim 16  having rolling contact fatigue resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       19 . The railroad wheel of  claim 16  having thermal cracking resistance at least equal to that of MR Grade C railroad wheel steel. 
   
   
       20 . The railroad wheel of  claim 16  having a strength at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       21 . A railroad wheel made of a steel having a pearlitic structure and comprised of:
 0.60 to 0.80 wt. % carbon;   0.70 to 1.00 wt. % silicon;   0.80 to 1.20 wt. % manganese;   0.10 to 0.30 wt. % chromium;   0.05 to 0.10 wt. % niobium;   0.20 to 0.30 wt. % molybdenum;   0.20 to 0.80 wt. % vanadium;   0.10 to 0.30 wt. % copper;   
     with the balance being iron and incidental impurities. 
   
   
       22 . The railroad wheel of  claim 21  having a Brinell hardness between 363 and 400. 
   
   
       23 . The railroad wheel of  claim 21  having rolling contact fatigue resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       24 . The railroad wheel of  claim 21  having thermal cracking resistance at least equal to that of MR Grade C railroad wheel steel. 
   
   
       25 . The railroad wheel of  claim 21  having a strength at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       26 . A railroad wheel made of a steel having a pearlitic structure and comprised of:
 0.60 to 0.80 wt. % carbon;   0.70 to 1.00 wt. % silicon;   0.80 to 1.20 wt. % manganese;   0.01 to 0.30 wt. % chromium;   0.01 to 0.10 wt. % niobium;   0.20 to 0.30 wt. % vanadium;   0.10 to 0.30 wt. % copper;   
     with the balance being iron and incidental impurities. 
   
   
       27 . The railroad wheel of  claim 26  having a Brinell hardness between 363 and 400. 
   
   
       28 . The railroad wheel of  claim 26  having rolling contact fatigue resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       29 . The railroad wheel of  claim 26  having thermal cracking resistance at least equal to that of AAR Grade C railroad wheel steel. 
   
   
       30 . The railroad wheel of  claim 26  having a strength at least equal to that of MR Grade C railroad wheel steel.