High temperature ceramic lubricant

Abstract

A gas turbine engine component having opposed surfaces in frictional contact with each other. An antifriction coating is disposed on one or more of the opposed surfaces. The antifriction coating includes a binder and a friction modifier. The weight ratio of the friction modifier to binder in the antifriction coating is greater than or equal to about 1:1.

1 . A gas turbine engine component comprising: 
 two or more opposed surfaces, the opposed surfaces being in frictional contact with each other;    an antifriction coating disposed on one or more of the opposed surfaces, the antifriction coating comprising a binder and a friction modifier; and    wherein the antifriction coating comprises a friction modifier and a binder in a weight ratio of friction modifier to binder greater than or equal to about 1:1.    
   
   
       2 . The component of  claim 1 , wherein the weight ratio of friction modifier to binder is at least about 1:1 to about 5:1  
   
   
       3 . The component of  claim 1 , wherein the weight ratio of friction modifier to binder is at least about 1.5:1 to about 3.5:1  
   
   
       4 . The component of  claim 1 , wherein the friction modifier is selected from the group consisting of tungsten sulfide, bismuth telluride, bismuth oxide and combinations thereof.  
   
   
       5 . The component of  claim 1 , wherein the binder is selected from the group consisting of titanium oxide, aluminum phosphate and combinations thereof.  
   
   
       6 . The component of  claim 1 , wherein the antifriction coating maintains a coefficient of friction between the opposed surfaces of less than about 0.95 in atmospheres substantially devoid of water vapor for at least 500,000 reciprocations.  
   
   
       7 . The component of  claim 1 , wherein the antifriction coating maintains a coefficient of friction between the opposed surfaces of less than about 0.95 at temperatures greater than about 400° F. for at least 500,000 reciprocations.  
   
   
       8 . The component of  claim 1 , wherein antifriction coating causes the opposed surfaces wear less than about 0.005 inches after at least 500,000 reciprocations.  
   
   
       9 . A variable stator vane comprising: 
 a bushing surface,    a vane surface, the bushing surface and vane surface being in frictional contact with each other;    an antifriction coating disposed on one or more of the bushing surface and vane surface, the antifriction coating comprising a binder and a friction modifier; and    wherein the antifriction coating comprises a friction modifier and a binder in a weight ratio of friction modifier to binder greater than or equal to about 1:1.    
   
   
       10 . The component of  claim 9 , wherein the vane surface further comprises a wear coating selected from the group consisting of nickel-based superalloys, titanium, titanium alloys, cobalt-based superalloys, iron-based superalloys, stainless steel, tungsten carbide and combinations thereof disposed thereon.  
   
   
       11 . The component of  claim 9 , wherein the weight ratio of friction modifier to binder is at least about 1:1 to about 5:1  
   
   
       12 . The component of  claim 9 , wherein the weight ratio of friction modifier to binder is at least about 1.5:1 to about 3.5:1  
   
   
       13 . The component of  claim 9 , wherein the friction modifier is selected from the group consisting of tungsten sulfide, bismuth telluride, bismuth oxide and combinations thereof.  
   
   
       14 . The component of  claim 9 , wherein the binder is selected from the group consisting of titanium oxide, aluminum phosphate and combinations thereof.  
   
   
       15 . The component of  claim 10 , wherein the antifriction coating maintains a coefficient of friction between the bushing surface and wear coated vane surface of less than about 0.95 in atmospheres substantially devoid of water vapor for at least 500,000 reciprocations.  
   
   
       16 . The component of  claim 10 , wherein the antifriction coating maintains a coefficient of friction between the bushing surface and wear coated vane surface of less than about 0.95 at temperatures greater than about 400° F. for at least 500,000 reciprocations.  
   
   
       17 . The component of  claim 10 , wherein antifriction coating causes the opposed surfaces wear less than about 0.005 inches after at least 500,000 reciprocations.  
   
   
       18 . A variable stator vane comprising: 
 a bushing surface,    a vane surface having a wear coating wear coating selected from the group consisting of nickel-based superalloys, titanium, titanium alloys, cobalt-based superalloys, iron-based superalloys, stainless steel, tungsten carbide and combinations thereof disposed thereon, the bushing surface and wear coated vane surface being in frictional contact with each other;    an antifriction coating disposed on one or more of the bushing surface and vane surface, the antifriction coating comprising a binder selected from the group consisting of titanium oxide, aluminum phosphate and combinations thereof and a friction modifier selected from the group consisting of tungsten sulfide, bismuth telluride, bismuth oxide and combinations thereof; and    wherein the antifriction coating comprises a friction modifier and a binder in a weight ratio of friction modifier to binder greater than or equal to about 1:1.    
   
   
       19 . The component of  claim 18 , wherein the antifriction coating maintains a coefficient of friction between the bushing surface and wear coated vane surface of less than about 0.95 at temperatures greater than about 400° F. in atmospheres substantially devoid of water vapor for at least 500,000 reciprocations.  
   
   
       20 . The component of  claim 18 , wherein antifriction coating causes the bushing surface and wear coated vane surface wear less than about 0.005 inches after at least 500,000 reciprocations.