Wear resistant high toughness steel

Abstract

A steel article is provided for improved wear resistance due to optimized hardness, toughness and temper resistance. In one exemplary embodiment, the steel article may have a composition including about 0,2 to 0.43 percent by weight of carbon, about 0.5 to about 3.0 percent by weight of silicon, about 0.01 to about 3.0 percent by weight of chromium, and 0.43 to about 2.5 percent by weight of vanadium.

What is claimed is: 
     
         1 . A steel article, comprising:
 about 0.2 to 0.43 percent by weight of carbon;   about 0.5 to about 3,0 percent by weight of silicon;   about 0.01 to about 3.0 percent by weight of chromium; and   0.43 to about 2.5 percent by weight of vanadium.   
     
     
         2 . The steel article of  claim 1 , further including about 0.01 to about 0.25 percent by weight of titanium, and about 0.002 to about 0.025 percent by weight of nitrogen. 
     
     
         3 . The steel article of  claim 1 , further including about 0.15 to about 0.5 percent by weight of molybdenum, and about 0,40 to about 2.0 percent by weight of manganese. 
     
     
         4 . The steel article of  claim 1 , further including less than or equal to about 0.02 percent by weight of aluminum, and about 0.0001 to about 0.010 percent by weight of boron. 
     
     
         5 . The steel article of  claim 1 , further including less than or equal to about 0.005 percent by weight of oxygen. 
     
     
         6 . The steel article of  claim 1 , further including less than or equal to about 0.045 percent by weight of sulphur, and less than or equal to about 0.04 percent by weight of phosphorous. 
     
     
         7 . The steel article of  claim 1 , wherein the steel article has a microstructure that is martensitic, a hardness of between about 54-60 HRC, and a fracture toughness of greater than or equal to about 70 Mpa√m. 
     
     
         8 . The steel article of  claim 1 , wherein the concentration of vanadium is between 0.45 to about 1.0 percent by weight. 
     
     
         9 . The steel article of  claim 1 , wherein the article is part of a machine undercarriage. 
     
     
         10 . A steel article, comprising;
 about 0.35 to 0.43 percent by weight of carbon;   0. 45 to about 1.3 percent by weight of vanadium;   about 0.02 to about 0.06 percent by weight of titanium;   about 1.45 to about 1.8 percent by weight of silicon; and   a martensitic microstructure.   
     
     
         11 . The steel article of  claim 10 , further including about 0.5 to about 1.0 percent by weight of manganese, and about 1.5 to about 2.0 percent by weight of chromium. 
     
     
         12 . The steel article of  claim 10 , further including about 0.008 to about 0.015 percent by weight of nitrogen. 
     
     
         13 . The steel article of  claim 10 , further including about 0.0075 to about 0.02 percent by weight of aluminum. 
     
     
         14 . The steel article of  claim 10 , Wherein the concentration of silicon is about 1.45 to about 1.6 percent by weight, and the concentration of titanium is about 0.03 to about 0.05 percent by weight. 
     
     
         15 . The steel article of  claim 10 , wherein the steel article has a microstructure that is martensitic and a hardness between about 54-60 HRC. 
     
     
         16 . A steel article, comprising:
 about 0.38 to 0.43 percent by weight of carbon;   about 1.45 to about 1.60 percent by weight of silicon;   about 1.60 to about 1.80 percent by weight of chromium;   0.43 to about 1.0 percent by weight of vanadium; and   about 0.009 to about 0.014 percent by weight of nitrogen.   
     
     
         17 . The steel article of  claim 16 , further including about 0.03 to about 0.05 percent by weight of titanium, and about 0.01 to about 0.02 percent by weight of aluminum. 
     
     
         18 . The steel article of  claim 16 , further including about 0.70 to about 0.85 percent by weight of manganese, and about 0.30 to about 0.40 percent by weight of molybdenum. 
     
     
         19 . The steel article of  claim 16 , further including about 0.001 to about 0.004 percent by weight of boron. 
     
     
         20 . The steel article of  claim 16 , further including less than or equal to about 0.003 percent by weight of oxygen, less than or equal to about 0.01 percent by weight of sulphur, and less than or equal to about 0.01 percent by weight of phosphorous.