Niobium-silicide based compositions, and related articles

Abstract

A refractory composition comprising niobium and silicon is disclosed. The amount of silicon present is less than about 9 atom %, based on total atomic percent for the composition. A turbine engine component (e.g., a gas turbine) is also described herein. The component comprises an alloy of niobium and silicon, wherein the amount of silicon present is less than about 9 atom %.

1 . A refractory composition comprising niobium and silicon, wherein the amount of silicon present is less than about 9 atom %, based on total atomic percent.  
   
   
       2 . The composition of  claim 1 , further comprising at least one element selected from the group consisting of titanium, hafnium, chromium, and aluminum.  
   
   
       3 . The composition of  claim 2 , wherein the amount of titanium present is in the range of about 5 atom % to about 45 atom %, based on total atomic percent.  
   
   
       4 . The composition of  claim 3 , wherein the amount of titanium present is in the range of about 10 atom % to about 30 atom %.  
   
   
       5 . The composition of  claim 2 , wherein the amount of hafnium present is in the range of about 1 atom % to about 20 atom %, based on total atomic percent.  
   
   
       6 . The composition of  claim 5 , wherein the amount of hafnium present is in the range of about 2 atom % to about 15 atom %.  
   
   
       7 . The composition of  claim 2 , wherein the amount of chromium present is in the range of about 1 atom % to about 25 atom %, based on total atomic percent.  
   
   
       8 . The composition of  claim 7 , wherein the amount of chromium present is in the range of about 5 atom % to about 15 atom %.  
   
   
       9 . The composition of  claim 2 , wherein the amount of aluminum present is in the range of about 1 atom % to about 20 atom %, based on total atomic percent.  
   
   
       10 . The composition of  claim 9 , wherein the amount of aluminum present is in the range of about 5 atom % to about 15 atom %.  
   
   
       11 . The composition of  claim 2 , wherein the amount of silicon present is in the range of about 5 atom % to about 8.5 atom %.  
   
   
       12 . The composition of  claim 2 , further comprising at least one platinum group metal selected from the group consisting of rhenium, osmium, iridium, platinum, ruthenium, rhodium, and palladium.  
   
   
       13 . The composition of  claim 2 , further comprising up to about 20 atom % rhenium, based on total atomic percent.  
   
   
       14 . The composition of  claim 2 , further comprising at least one element selected from the group consisting of tungsten, tantalum, and molybdenum.  
   
   
       15 . The composition of  claim 12 , further comprising at least one element selected from the group consisting of tungsten, tantalum, and molybdenum.  
   
   
       16 . The composition of  claim 2 , further comprising at least one rare earth metal.  
   
   
       17 . The composition of  claim 2 , further comprising at least one element selected from the group consisting of boron, carbon, germanium, zirconium, vanadium, tin, nitrogen, iron, and indium.  
   
   
       18 . The composition of  claim 15 , further comprising at least one element selected from the group consisting of boron, carbon, germanium, zirconium, vanadium, tin, nitrogen, iron, and indium.  
   
   
       19 . The composition of  claim 1 , wherein the amount of silicon present is at least about 0.5 atom %.  
   
   
       20 . The composition of  claim 1 , characterized by a microstructure comprising a metallic Nb-base phase and at least one metal silicide phase of the formula M 3 Si or M 5 Si 3 , wherein M is at least one element selected from the group consisting of Nb, Hf, Ti, Mo, Ta, W, a platinum group metal, and combinations thereof.  
   
   
       21 . A turbine engine component, formed of a material comprising an alloy of niobium and silicon, wherein the amount of silicon present is less than about 9 atom %, based on total atomic percent.  
   
   
       22 . A niobium-silicide based composition, comprising niobium, silicon, and at least one element selected from the group consisting of titanium, hafnium, chromium, and aluminum; 
 wherein the amount of silicon in the composition is less than about 9 atom %, based on total atomic percent; and    wherein the composition comprises a metallic Nb-base phase and at least one metal silicide phase of the formula M 3 Si or M 5 Si 3 , wherein M is at least one element selected from the group consisting of Nb, Hf, Ti, Mo, Ta, W, a platinum group metal, and combinations thereof.