Stainless steel alloys, turbocharger components formed from the stainless steel alloys, and methods for manufacturing the same

Abstract

Disclosed is an austenitic stainless steel alloy that includes or consists of, by weight, about 22.0% to about 23.0% chromium, about 4.0% to about 5.0% nickel, about 4.0% to about 5.0% manganese, about 0.2% to about 0.4% molybdenum, about 0.2% to about 0.4% niobium, about 0.5% to about 1.5% silicon, about 0.35% to about 0.45% carbon, about 0.2% to about 0.28% nitrogen, a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts. The elements phosphorus and sulfur are excluded from the alloy beyond impurity levels. Turbocharger turbine housings made of the stainless steel alloy, and methods of making the same, are also disclosed. The stainless steel alloy is suitable for use in turbocharger turbine applications for temperatures up to about 1,000° C.

1 . An austenitic stainless steel alloy, comprising, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         2 . The austenitic stainless steel alloy of  claim 1 , comprising about 22.3% to about 22.7% chromium. 
     
     
         3 . The austenitic stainless steel alloy of  claim 1 , comprising about 4.3% to about 4.7% nickel. 
     
     
         4 . The austenitic stainless steel alloy of  claim 1 , comprising about 4.3% to about 4.7% manganese. 
     
     
         5 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.25% to about 0.35% molybdenum. 
     
     
         6 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.8% to about 1.2% silicon. 
     
     
         7 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.37% to about 0.43% carbon. 
     
     
         8 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.22% to about 0.26% nitrogen. 
     
     
         9 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.25% to about 0.35% niobium. 
     
     
         10 . The austenitic stainless steel alloy of  claim 1 , consisting of, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         11 . The austenitic stainless steel alloy of  claim 1 , comprising about 0.3% to about 0.5% copper. 
     
     
         12 . The austenitic stainless steel alloy of  claim 11 , consisting of, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.3% to about 0.5% copper;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         13 . A turbocharger turbine component comprising:
 an austenitic stainless steel alloy, wherein the austenitic stainless steel alloy comprises, by weight:   about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         14 . The turbocharger turbine component of  claim 13 , wherein the austenitic stainless steel alloy consists of, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         15 . The turbocharger turbine component of  claim 13 , wherein the austenitic stainless steel alloy comprises about 0.3% to about 0.5% copper. 
     
     
         16 . The turbocharger turbine component of  claim 15 , wherein the austenitic stainless steel alloy consists of, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.3% to about 0.5% copper;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         17 . The turbocharger turbine component of  claim 13 , wherein the turbocharger turbine component comprises a turbocharger turbine housing. 
     
     
         18 . A vehicle comprising the turbocharger turbine component of  claim 13 . 
     
     
         19 . A method of making a turbocharger turbine component comprising forming the turbocharger turbine component using an austenitic stainless steel alloy, wherein the austenitic stainless steel alloy comprises, by weight:
 about 22.0% to about 23.0% chromium;   about 4.0% to about 5.0% nickel;   about 4.0% to about 5.0% manganese;   about 0.2% to about 0.4% molybdenum;   about 0.2% to about 0.4% niobium;   about 0.5% to about 1.5% silicon;   about 0.35% to about 0.45% carbon;   about 0.2% to about 0.28% nitrogen; and   a balance of iron, and other inevitable/unavoidable impurities that are present in trace amounts, wherein phosphorus and sulfur are excluded from the alloy beyond impurity levels.   
     
     
         20 . The method of  claim 19 , wherein the austenitic stainless steel alloy comprises about 0.3% to about 0.5% copper.