Gas turbine engine fan blade tip treatment

Abstract

A method of manufacturing a fan blade includes providing a metallic fan blade body, and applying at least a 200 volt potential to the fan blade body in a solution to produce a crystalline oxidation layer. A fan blade for a gas turbine engine includes a metallic fan blade body having a tip with a crystalline oxidation layer. A fan blade for a gas turbine engine includes a metallic fan blade body having a tip with a titanium dioxide layer.

What is claimed is: 
     
         1 . A method of manufacturing a fan blade comprising:
 providing a metallic fan blade body; and   applying at least a 200 volt potential to the fan blade body in a solution to produce a crystalline oxidation layer.   
     
     
         2 . The method according to  claim 1 , wherein the fan blade body includes a tip, and comprising the step of masking the fan blade body to leave at least the tip exposed, the tip having the crystalline oxidation layer. 
     
     
         3 . The method according to  claim 1 , wherein the fan blade body provides an electrode in an alkaline solution. 
     
     
         4 . The method according to  claim 3 , comprising generating a plasma discharge on a surface of the fan blade body. 
     
     
         5 . The method according to  claim 1 , wherein the crystalline oxidation layer is aluminum oxide. 
     
     
         6 . The method according to  claim 5 , wherein the crystalline oxidation layer has a thickness of at least 0.0005 inch (0.013 mm). 
     
     
         7 . The method according to  claim 5 , wherein the crystalline oxidation layer has a hardness of at least 1700 HV. 
     
     
         8 . The method according to  claim 5 , wherein the fan blade body is one of a 7000 series and a 2000 series aluminum alloy. 
     
     
         9 . The method according to  claim 2 , comprising the steps of removing the masking and adhering a sheath to a leading edge of the fan blade body. 
     
     
         10 . The method according to  claim 9 , wherein the adhering step includes arranging an adhesive-saturated scrim between the sheath and the leading edge. 
     
     
         11 . The method according to  claim 10 , comprising the step of coating the fan blade body with polyurethane to provide a fan blade contour along with the sheath. 
     
     
         12 . The method according to  claim 11 , wherein the crystalline oxidation layer is left exposed subsequent to the coating step. 
     
     
         13 . A fan blade for a gas turbine engine comprising:
 a metallic fan blade body having a tip with a crystalline oxidation layer.   
     
     
         14 . The fan blade according to  claim 13 , wherein the crystalline oxidation layer has a thickness of at least 0.005 inch (0.12 mm). 
     
     
         15 . The fan blade according to  claim 14 , wherein the crystalline oxidation layer has a hardness of at least 1700 HV. 
     
     
         16 . The fan blade according to  claim 15 , wherein the fan blade body is one of a 7000 series and a 2000 series aluminum alloy. 
     
     
         17 . The fan blade according to  claim 16 , comprising a sheath adhered to a leading edge of the fan blade body. 
     
     
         18 . The fan blade according to  claim 17 , comprising a polyurethane coating arranged over the fan blade body and adjoining the sheath to provide a fan blade contour. 
     
     
         19 . A fan blade for a gas turbine engine comprising:
 a metallic fan blade body having a tip with a titanium dioxide layer.   
     
     
         20 . The fan blade according to  claim 19 , wherein the tip includes a plasma spray coating arranged on the titanium dioxide layer, which is provided between the plasma spray coating and the metallic fan blade body. 
     
     
         21 . The fan blade according to  claim 19 , wherein the amorphous titanium oxidation layer has a thickness of at least 0.0005 inch (0.13 mm). 
     
     
         22 . The fan blade according to  claim 21 , wherein the amorphous titanium oxidation layer has a hardness of at least 640 HV. 
     
     
         23 . The fan blade according to  claim 22 , wherein the fan blade body is one of a 7000 series and a 2000 series aluminum alloy. 
     
     
         24 . The fan blade according to  claim 23 , comprising a sheath adhered to a leading edge of the fan blade body. 
     
     
         25 . The fan blade according to  claim 24 , comprising a polyurethane coating arranged over the fan blade body and adjoining the sheath to provide a fan blade contour.