Method of Forming a Workpiece
A method of forming a ceramic metal composite workpiece comprises a step of providing a forming assembly with first and second shaping surfaces that together form a chamber. The chamber is shaped substantially similar to a desired external geometry of a green body of the workpiece, and at least one of the surfaces comprises a pressing mechanism adapted to move the surface with respect to the other surface. The method also comprises placing into the chamber a malleable composite material and an insert comprising a shape substantially similar to a desired internal surface geometry of the green body. The method also comprises a step of pressing the malleable composite material to form the green body such that at least a portion of the malleable composite material flows around at least a portion of the insert to form the green body with the desired external and internal surface geometries.
1 . A method of forming a ceramic metal composite workpiece, comprising the steps of:
providing a forming assembly with first and second shaping surfaces together forming a chamber shaped substantially similar to a desired external geometry of a green body of the workpiece, and at least one of the surfaces comprising a pressing mechanism adapted to move the surface with respect to the other surface;
placing a malleable composite material and an insert comprising a shape substantially similar to a desired internal surface geometry of the green body within the chamber;
pressing the malleable composite material to form the green body such that at least a portion of the malleable composite material flows around at least a portion of the insert to form the green body with the desired external and internal surface geometries.
2 . The method of claim 1 , wherein the method comprises an additional step of sintering the green body.
3 . The method of claim 2 , wherein the step of sintering is done under pressure.
4 . The method of claim 2 , wherein the insert vaporizes and/or melts out of the green body during the step of sintering the green body.
5 . The method of claim 2 , wherein the method further comprises a step of brazing the sintered workpiece to an impact tip comprising a superhard material disposed on an impact surface of the tip.
6 . The method of claim 1 , wherein the step of pressing the malleable composite material comprises pressing the material with a pressure of at least 5000 psi.
7 . The method of claim 1 , wherein the insert comprises a vaporization temperature of 600° C. or lower.
8 . The method of claim 1 , wherein the insert comprises a diffusion barrier.
9 . The method of claim 1 , wherein the insert comprises an insert material selected from the group consisting of plastics, metals, waxes, polymers, and combinations thereof.
10 . The method of claim 1 , wherein at least a portion of the insert has a shape comprising a generally spherical geometry, a generally hourglass-shaped geometry, a generally cone-shaped geometry, or combinations thereof.
11 . The method of claim 1 , wherein the insert comprises at least one ledge, lip, taper, protrusion, ridge, prong, slot, or combinations thereof.
12 . The method of claim 1 , wherein the insert comprises inner and outer diameters.
13 . The method of claim 1 , wherein the insert comprises a thread form disposed on an outer surface of the insert.
14 . The method of claim 1 , wherein the composite material comprises a tungsten carbide.
15 . The method of claim 1 , wherein the composite material comprises a polycrystalline diamond.
16 . The method of claim 1 , wherein the malleable composite material comprises a sintering temperature of at least 1300° C.
17 . The method of claim 1 , wherein the green body comprises a ledge, lip, taper, protrusion, ridge, slot, or combinations thereof.
18 . The method of claim 1 , wherein the insert is placed into the chamber prior to placing the malleable composite material in the chamber.
19 . The method of claim 1 , wherein the malleable composite material is placed into the chamber prior to placing the insert in the chamber.
20 . The method of claim 1 , wherein at least one of the shaping surfaces comprises an insert connection and/or release mechanism.