Diamond wire drawing die blanks and methods of making the same

Claim 1

The method of forming wire drawing die blanks comprising the steps of: a. forming a compact of a superalloy powder containing a diamond and having an outside diameter smaller than the diameter of the drawing apparatus die aperture in which it is to be used by: (1) metering substantially one half of a metal powder required to form said compact into a die cavity for receiving powder metal; (2) partially compressing said substantially one half of the metal powder into a flat member of substantially uniform thickness in said die cavity; (3) forming a central conical shaped depression in the top surface of said compacted powder metal; (4) placing a diamond in said conical depression without removing the compacted powder metal from said die cavity; (5) adding the remaining metal powder required to form a compact into said die cavity over the diamond and said partially compressed one half without removing the compacted powder metal from said die cavity; (6) compressing said remaining metal powder and said substantially one half of metal powder around said diamond in said die cavity; and (7) sintering said metal powder compact; b. pressing a ring of powdered stainless steel having an inner annular opening adapted to receive the sintered superalloy compact containing a diamond and an outer diameter adapted to fit a drawing die apparatus aperture in which it is to be used, said powdered stainless steel having a shrinkage coefficient on sintering sufficient to cause the ring to shrink onto and tightly engage said compact, and c. sintering the stainless steel at a temperature below the melting point of the compact to consolidate and shrink the stainless steel onto the compact and to metallurgically bond the stainless steel and the superalloy of the compact.

Claim 2

The method of forming wire drawing die blanks comprising the steps of: a. forming a compact of a superalloy powder containing a diamond and having an outside diameter smaller than the diameter of the drawing apparatus die aperture in which it is to be used by: (1) metering substantially one half of a metal powder required to form said compact into a die cavity for receiving powder metal; (2) partially compressing said substantially one half of the metal powder into a flat member of substantially uniform thickness in said die cavity; (3) forming a central conical shaped depression in the top surface of said compacted powder metal; (4) placing a diamond in said conical depression without removing the compacted powder metal from said die cavity; (5) adding the remaining metal powder required to form a compact into said die cavity over the diamond and said partially compressed one half without removing the compacted powder metal from said die cavity; (6) compressing said remaining metal powder and said substantially one half of metal powder around said diamond in said die cavity; and (7) sintering said metal powder compact; b. pressing a ring of powdered stainless steel having an inner annular opening adapted to receive the sintered superalloy compact containing a diamond and an outer diameter adapted to fit a drawing die apparatus aperture in which it is to be used, said powdered stainless steel having a shrinkage coefficient on sintering sufficient to cause the ring to shrink onto and tightly engage said compact, and c. sintering the stainless steel at a temperature below the melting point of the compact to consolidate and shrink the stainless steel onto the compact and to metallurgically bond the stainless steel and the superalloy of the compact.