Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
153 words
An improved method for making a composite diamond compact having an inner polycrystalline diamond mass surrounded by and bonded to an outer mass of a material selected from metals, metal alloys and cermets, which method comprises: A. Positioning in an enclosure a sample comprising a formed hollow mass of a material selected from metals, metal alloys and cermets, which contains a diamond forming catalyst and a mass of non-diamond carbon within the formed hollow mass and in contact therewith; B. Subjecting the sample to pressure-temperature conditions within the diamond stable region and above the catalyst melting point; C. Reducing the temperature and pressure of the sample; and D. Recovering the resulting composite diamond compact; wherein the improvement comprises disposing a mono-layer of diamond seed crystals having a largest dimension of from 0.1 to 500 microns at the interface between the hollow outer mass and the inner mass of non-diamond carbon in Step A.
Claim 2
Dependent Claim
153 words
An improved method for making a composite diamond compact having an inner polycrystalline diamond mass surrounded by and bonded to an outer mass of a material selected from metals, metal alloys and cermets, which method comprises: A. Positioning in an enclosure a sample comprising a formed hollow mass of a material selected from metals, metal alloys and cermets, which contains a diamond forming catalyst and a mass of non-diamond carbon within the formed hollow mass and in contact therewith; B. Subjecting the sample to pressure-temperature conditions within the diamond stable region and above the catalyst melting point; C. Reducing the temperature and pressure of the sample; and D. Recovering the resulting composite diamond compact; wherein the improvement comprises disposing a mono-layer of diamond seed crystals having a largest dimension of from 0.1 to 500 microns at the interface between the hollow outer mass and the inner mass of non-diamond carbon in Step A.
Claim 3
Dependent Claim
28 words
The improved process as recited in claim 1 wherein the inner mass is in the form of a right circular cylinder and the hollow outer mass is cup-shaped.
Claim 4
Dependent Claim
14 words
The improved process as recited in claim 2 wherein the non-diamond carbon is graphite.
Claim 5
Dependent Claim
96 words
The improved method as recited in claim 3 wherein the hollow outer mass is made of material selected from the group consisting of: a metal bonded carbide selected from the group consisting of tungsten carbide, titanium carbide and tantalum carbide bonded with a material selected from cobalt, nickel and iron; a cermet of nickel-bonded chromium carbide; an alloy steel containing chromium, nickel and cobalt; a nickel based alloy; a cobalt based alloy; and an alloy steel containing at least ten weight percent of the carbide forming elements selected from chromium, titanium, zirconium, vanadium, tungsten and silicon.
Claim 6
Dependent Claim
57 words
The improved method as recited in claim 4 wherein the pressure in Step B ranges from about 55 to 80 Kbar and the temperature ranges from about 1300° to 1800° C., and wherein the diamond seed crystals have a largest dimension of from 1 to 50 microns and have a spacing of two crystal diameters or less.
Claim 7
Dependent Claim
22 words
The improved method as recited in claim 5 wherein the conditions of Step B are achieved by direct heating of the sample.
Claim 8
Dependent Claim
33 words
The improved method as recited in claim 5 wherein the cup-shaped outer mass has a coefficient of thermal expansion slightly higher than diamond, in order to place the inner mass in radial compression.
Claim 9
Dependent Claim
52 words
The improved method as recited in claim 7 wherein the cup-shaped outer mass is made of a material having a compressive strength of 2.8-5.5×10 6 K Pascals and a modulus of elasticity of from 2.1 to 6.6×10 6 K Pascals selected from the group consisting of steel, steel alloys and cemented carbides.
Claim 10
Dependent Claim
24 words
The improved method as recited in claim 7 wherein the cup-shaped outer mass has a stable carbide content of at least 10% by weight.