Improved sweep through process for making polycrystalline compacts

Claim 2

An improved process for making a polycrystalline diamond compact comprising subjecting a mass of diamond particles, which mass is in contact with a source of catalyst for diamond recrystallization, to a high pressure/high temperature process which results in a compact characterized by diamond-to-diamond bonding and containing an interstitial metal phase comprising catalyst; wherein the improvement comprises placing in contact with the mass of diamond particles an additional metal or metal alloy selected from the group consisting of: (a) single metals. which: (i) have a lower melting point than the catalyst; (ii) do not interfere with the function of the catalyst; and (iii) are miscible with the catalyst; and (b) alloys of metals as described in (a) above, which alloys d& not interfere with the function of the catalyst.

Claim 3

The improved process of claim 1 wherein the additional metal or metal alloy forms an alloy with the catalyst.

Claim 4

The improved process of claim 1 wherein the additional metal or metal alloy is mixed with the diamond.

Claim 5

The improved process of claim 1 wherein the catalyst is part of an alloy with the additional metal which alloy fmctions both as the catalyst source and the additional metal alloy.

Claim 6

The improved process of claim 4 wherein the alloy is selected from the group consisting of alloys of cobalt and copper and alloys of nickel and copper.

Claim 7

The improved process of claim 1 which further comprises removing substantially all of the metal phase from the compact.

Claim 8

The improved process of claim 1 wherein the additional metal or metal alloy is placed between the diamond and-the catalyst source.

Claim 9

The improved process of claim 7 in which the additional metal is a single metal which sweeps through the diamond mass ahead of the catalyst.

Claim 10

The improved process of claim 8 wherein the additional metal is selected from the group consisting of copper, tin, aluminum, zinc, magnesium and antimony.

Claim 11

The improved process of claim 9 wherein the additional metal is copper.

Claim 12

The improved process of claim 9 wherein the catalyst source is a mass selected from the group consisting of cemented metal carbide and carbide molding powders wherein at least part of the cementing agent is a catalyst.

Claim 13

The process of claim 11 wherein the catalyst source is in the form of an annulus surrounding the diamond particles.

Claim 14

The compact produced by the process of claims 2, 4, 8, 11 or 12.

Claim 15

An improved process for making a polycrystalline cubic boron nitride compact comprising subjecting a mass of cubic boron nitride particles, which mass is in contact with a source of sintering catalyst to a high pressure/high temperature process resulting in a compact having at least 70 volume percent cubic boron nitride content and an interstitial metal phase comprising catalyst within the resulting polycrystalline mass; wherein the improvement comprises placing in contact with the mass of cubic boron nitride particles an additional metal or metal alloy selected from the group consisting of: (a) single metals which: (i) have a lower melting point than the catalyst; (ii) do not interfere with the function of the catalyst; and (iii) are miscible with the catalyst; and (b) alloys of metals as described in (a) above, which alloys do not interfere with the function of the catalyst.

Claim 16

An improved process for making a polycrystalline cubic boron nitride compact comprising subjecting a mass of cubic boron nitride particles, which mass is in contact with a source of sintering catalyst to a high pressure/high temperature process resulting in a compact having at least 70 volume percent cubic boron nitride content and an interstitial metal phase comprising catalyst within the resulting polycrystalline mass; wherein the improvement comprises placing in contact with the mass of cubic boron nitride particles an additional metal or metal alloy selected from the group consisting of: (a) single metals which: (i) have a lower melting point than the catalyst; (ii) do not interfere with the function of the catalyst; and (iii) are miscible with the catalyst; and (b) alloys of metals as described in (a) above, which alloys do not interfere with the function of the catalyst.

Claim 17

The improved process of claim 14 wherein the additional metal or metal alloy forms an alloy with the catalyst.

Claim 18

The improved process of claim 14 wherein the additional metal or metal alloy is mixed with the cubic boron nitride.

Claim 19

The improved process of claim 14 wherein the sintering catalyst is part of an alloy with the additional metal which alloy functions both as the catalyst source and the additional metal alloy.

Claim 20

The improved process of claim 14 which further comprises removing substantially all of the metal phase from the compact.

Claim 21

The improved process of claim 14 wherein the additional metal or metal alloy is placed between the cubic boron nitride and the catalyst source.

Claim 22

The improved process of claim 19 in which the additional metal is a single metal which sweeps through the cubic boron nitride mass ahead of the catalyst.

Claim 23

The improved process of claim 20 wherein the additional metal is selected from the group consisting of copper, tin, aluminum, zinc, magnesium and antimony.

Claim 24

The improved method of claim 21 wherein the additional metal is copper.

Claim 25

The improved method of claim 21 wherein the catalyst source is a mass selected from the group consisting of cemented metal carbide and carbide molding powders wherein at least part of the cementing agent is a catalyst.

Claim 26

The compact produced by the process of claims 15, 17, 20 or 23.

Claim 27

A polycrystalline diamond or cubic boron nitride compact containing within the interstices between crystal grains a catalyst and an additional metal which: has a lower melting point than the catalyst; does not interfere with the function of the catalyst; and is miscible with the catalyst.

Claim 28

A polycrystalline diamond or cubic boron nitride compact containing within the interstices between crystal grains a catalyst and an additional metal which: has a lower melting point than the catalyst; does not interfere with the function of the catalyst; and is miscible with the catalyst.

Claim 29

The polycrystalline diamond or cubic boron nitride compact of claim 25 wherein the additional metal will sweep through the abrasive particle mass ahead of the catalyst in the high pressure/high temperature sintering process.

Claim 30

The polycrystalline diamond or cubic boron nitride compact of claim 26 wherein the additional metal is copper.

Claim 31

The polycrystalline compact of claim 26 which contains an alloy of the additional metal and the catalyst.