Systems and methods for making blade sheaths

Abstract

A method of making a sheath for an airfoil may include the steps of forming an upper sleeve and a lower sleeve, and forming a central portion bonded to the upper sleeve and the lower sleeve. The central portion may be formed by depositing a material on the upper sleeve and the lower sleeve. A portion of the material may be removed from at least one of the central portion, the upper sleeve, or the lower sleeve. The sheath may include a first flank, a central portion bonded to the first flank, and a second flank bonded to the central portion. The central portion may have a substantially uniform microstructure resulting from additive manufacturing.

What is claimed is: 
     
         1 . A sheath for an airfoil comprising:
 a first flank having a contour matching a suction side of the airfoil;   a central portion bonded to the first flank, wherein the central portion is deposited using additive manufacturing; and   a second flank bonded to the central portion and having a contour matching a pressure side of the airfoil.   
     
     
         2 . The sheath of  claim 1 , wherein the central portion comprises a substantially uniform microstructure. 
     
     
         3 . The sheath of  claim 2 , wherein the first flank is formed from a sheet of a metal. 
     
     
         4 . The sheath of  claim 3 , wherein the metal comprises at least one of titanium, aluminum, nickel, or steel. 
     
     
         5 . The sheath of  claim 1 , wherein the central portion comprises a titanium alloy. 
     
     
         6 . The sheath of  claim 1 , further comprising an inner surface having a curved surface to join the first flank and the second flank. 
     
     
         7 . The sheath of  claim 6 , wherein the inner surface is substantially smooth with a substantially uniform microstructure. 
     
     
         8 . A fan comprising:
 a blade having a leading edge, a pressure side, a suction side, and a trailing edge; and   a sheath bonded to the blade by an adhesive, wherein the sheath comprises a first flank on the pressure side, a second flank on the suction side, and a central portion joining the first flank and the second flank, wherein the central portion comprises a substantially uniform microstructure.   
     
     
         9 . The fan of  claim 8 , wherein the central portion is formed by applying a heat source to a wire to deposit material on the first flank and the second flank. 
     
     
         10 . The fan of  claim 8 , wherein the sheath comprises at least one of titanium, aluminum, nickel, or steel. 
     
     
         11 . The fan of  claim 8 , wherein an inner surface of the central portion that joins the first flank and the second flank is substantially smooth.