Alloys for high temperature applications, articles made therefrom, and method for repair of articles

Abstract

An alloy for use in high temperature applications is presented. The alloy comprises, in atom percent, at least about 50% rhodium (Rh); at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof; from about 5% to about 24% ruthenium (Ru); and from about 1% to about 40% chromium (Cr); wherein the alloy comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in the alloy, respectively. Articles comprising the alloy and methods employing the alloy for repairing articles are also presented.

1 . An alloy comprising, in atom percent: 
 at least about 50% rhodium (Rh);    at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof;    from about 5% to about 24% ruthenium (Ru); and    from about 1% to about 40% chromium (Cr);    wherein said alloy comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in said alloy, respectively.    
     
     
         2 . The alloy of  claim 1 , comprising in atom percent 
 from about 7% to about 20% ruthenium, and    from about 1% to about 25% chromium.    
     
     
         3 . The alloy of  claim 1 , comprising in atom percent 
 from about 8% to about 20% ruthenium, and    from about 1% to about 10% chromium.    
     
     
         4 . An article for use in a high temperature, oxidative environment, said article comprising: 
 an alloy comprising, in atom percent,    at least about 50% rhodium (Rh);    at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof;    from about 5% to about 24% ruthenium (Ru); and    from about 1% to about 40% chromium (Cr);    wherein said alloy comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in said alloy, respectively.    
     
     
         5 . The article of  claim 4 , wherein said article comprises a coating disposed on a substrate, and wherein said coating comprises said alloy.  
     
     
         6 . The article of  claim 4 , wherein said article comprises a component of a gas turbine assembly.  
     
     
         7 . The article of  claim 6 , wherein said component comprises at least one of a turbine blade, a turbine vane, and a combustor component.  
     
     
         8 . The article of  claim 7 , wherein said alloy is disposed at at least one component section selected from the group consisting of a leading edge, a trailing edge, and a blade tip.  
     
     
         9 . The article of  claim 4 , wherein said alloy comprises 
 from about 7% to about 20% ruthenium, and    from about 1% to about 25% chromium.    
     
     
         10 . The article of  claim 4 , wherein said alloy comprises 
 from about 8% to about 20% ruthenium, and    from about 1% to about 10% chromium.    
     
     
         11 . The article of  claim 4 , wherein said article comprises a repaired article.  
     
     
         12 . A gas turbine engine component comprising: 
 an alloy comprising, in atom percent,    at least about 50% rhodium (Rh);    at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof;    from about 7% to about 20% ruthenium (Ru); and    from about 1% to about 25% chromium (Cr);    wherein said alloy comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in said alloy, respectively; wherein said turbine engine component comprises one of a blade and a vane and said alloy is disposed in at least one section of said component selected from the group consisting of a leading edge, a trailing edge, and a blade tip.    
     
     
         13 . A method for repairing an article, said method comprising: 
 providing an article;    providing a repair material, said repair material comprising, in atom percent,    at least about 50% rhodium (Rh),    at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof,    from about 5% to about 24% ruthenium (Ru), and    from about 1% to about 40% chromium (Cr),    wherein said repair material comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in said repair material, respectively; and    joining said repair material to said article.    
     
     
         14 . The method of  claim 13 , wherein said repair material comprises, in atom percent, 
 from about 7% to about 20% ruthenium, and    from about 1% to about 25% chromium.    
     
     
         15 . The method of  claim 13 , wherein said repair material comprises, in atom percent, 
 from about 8% to about 20% ruthenium, and    from about 1% to about 10% chromium.    
     
     
         16 . The method of  claim 13 , wherein joining comprises disposing a coating onto said article, said coating comprising said repair material.  
     
     
         17 . The method of  claim 16 , wherein disposing said coating comprises disposing said coating by at least one process selected from the group consisting of thermal spraying, plasma spraying, HVOF spraying, and laser deposition.  
     
     
         18 . The method of  claim 13 , wherein joining comprises at least one of welding, brazing, and diffusion bonding.  
     
     
         19 . The method of  claim 13 , wherein said article comprises a component of a gas turbine engine selected from the group consisting of a blade, a vane, and a combustion component.  
     
     
         20 . The method of  claim 19 , wherein joining comprises disposing said repair material at at least one component section selected from the group consisting of a leading edge, a trailing edge, and a blade tip.  
     
     
         21 . A method for repairing a gas turbine engine component, said method comprising: 
 providing at least one gas turbine engine component selected from the group consisting of a blade, a vane, and a combustion component;    providing a repair material, said repair material comprising, in atom percent,    at least about 50% rhodium (Rh),    at least about 5% of a metal selected from the group consisting of platinum (Pt), palladium (Pd), and combinations thereof,    from about 7% to about 20% ruthenium (Ru), and    from about 1% to about 25% chromium (Cr),    wherein said repair material comprises less than about 50% by volume of an A3-structured phase, and wherein the quantity defined by the expression ([Cr]+2[Ru]) is in the range from about 25% to about 50%, where [Ru] and [Cr] are the atom percentages of ruthenium and chromium in said repair material, respectively; and    joining said repair material to said component by disposing said repair material at at least one component section selected from the group consisting of a leading edge, a trailing edge, and a blade tip.