Method for making blade protective sheaths

Claim 1

A method for protecting the edge of an aerodynamic blade comprising: providing a metal sheath mid-section element having a top and a bottom surface, said mid-section element being selected from the group consisting of titanium, nickel and alloys thereof; covering said top and bottom surface with an aluminum bonding material; laying up a metal top and bottom sheath cover element on each of said top and bottom surfaces of said mid-section element, said top and bottom cover elements being selected from the group consisting of titanium, nickel and alloys thereof and having contact surfaces wider than said top and bottom surfaces of said sheath mid-section element to overhang opposite sides of the same and thereby form channels adapted to receive the edge of said blade; said aluminum bonding material having a solidus temperature which is lower than the solidus temperature of each of said mid-section element and said top and bottom cover elements; subjecting the layup to heat and pressure in a die for a time sufficient to bring the temperature of said bonding material to a temperature which is below but within approximately 20° F of its solidus temperature to solid state diffusion bond said mid-section and cover elements together without forming intermetallics, said temperature being 900°-1075° F, said pressure being 1,000-10,000 psi and said time being 2-90 minutes; severing the bonded product through said top surface, said mid-section element and said bottom surface to form two U-shaped protective sheaths; finishing said U-shaped protective sheath to final shape; and bonding said U-shaped protective sheath to said blade edge.

Claim 2

A method for protecting the edge of an aerodynamic blade comprising: providing a metal sheath mid-section element having a top and a bottom surface, said mid-section element being selected from the group consisting of titanium, nickel and alloys thereof; covering said top and bottom surface with an aluminum bonding material; laying up a metal top and bottom sheath cover element on each of said top and bottom surfaces of said mid-section element, said top and bottom cover elements being selected from the group consisting of titanium, nickel and alloys thereof and having contact surfaces wider than said top and bottom surfaces of said sheath mid-section element to overhang opposite sides of the same and thereby form channels adapted to receive the edge of said blade; said aluminum bonding material having a solidus temperature which is lower than the solidus temperature of each of said mid-section element and said top and bottom cover elements; subjecting the layup to heat and pressure in a die for a time sufficient to bring the temperature of said bonding material to a temperature which is below but within approximately 20° F of its solidus temperature to solid state diffusion bond said mid-section and cover elements together without forming intermetallics, said temperature being 900°-1075° F, said pressure being 1,000-10,000 psi and said time being 2-90 minutes; severing the bonded product through said top surface, said mid-section element and said bottom surface to form two U-shaped protective sheaths; finishing said U-shaped protective sheath to final shape; and bonding said U-shaped protective sheath to said blade edge.