Low pressure bonding of PCD bodies and method

Claim 2

Claim 2. A temperature stable diamond product as set forth in Claim 1 wherein said diamond piece is a synthetic diamond piece which includes a face, at least a portion of said face being in contact with said matrix carrier, and said metal matrix carrier being tungsten carbide and extending to the rear of the face a predetermined distance and forming a backing integral with said diamond piece.

Claim 3

Claim 3. A temperature stable diamond product as set forth in Claim 1 wherein said temperature stable diamond includes at least one side face, and said side face being coated with said metal which is a carbide former and being at least partially in contact with said matrix carrier.

Claim 4

Claim 4. A temperature stable diamond product as set forth in claim 1 wherein said product includes a plurality of initially separate temperature stable diamond pieces arranged in a predetermined pattern and including opposed surface portions forming a small gap therebetween, and matrix carrier being located in said gap and contacting at least a portion of the surface portions of said temperature stable diamond elements.

Claim 5

Claim 5. A temperature stable diamond product as set forth in claim 4 wherein at least some of said temperature stable diamond elements are generally triangular in shape.

Claim 6

Claim 6. A temperature stable diamond product as set forth in claim 1 wherein said product is generally circular in shape and said temperature stable diamond is generally circular in shape.

Claim 7

Claim 7. A temperature stable diamond product as set forth in claim 1 wherein said product is a cutter for an earth boring bit.

Claim 8

Claim 8. A temperature stable diamond product as set forth in claim 7 in which said product includes more than one initially separate temperature stable diamond elements.

Claim 9

Claim 9. A temperature stable diamond product as set forth in claim 4 in which said gap is between 6 and 30 mils.

Claim 10

Claim 10. A temperature stable diamond product as set forth in claim 1 in which said coating has a thickness of up to about 30 microns.

Claim 11

Claim 11. A temperature stable diamond product as set forth in claim 1 in which said matrix carrier includes a carbide and a binder.

Claim 12

Claim 12. A temperature stable diamond product as set forth in claim 1 in which said matrix carrier is a sintered metal.

Claim 13

Claim 13. A temperature stable diamond product as set forth in claim 1 in which said coating includes at least one metal selected from the metals of Group IVA, VA, VIA, VIIA and alloys and mixtures thereof.

Claim 14

Claim 14. A temperature stable diamond product as set forth in claim 11 in which said carbide is selected from the group consisting of the carbides of tungsten, chromium, niobium, titanium, tantalum, zirconium and molybdenum.

Claim 15

Claim 15. A temperature stable diamond product as set forth in claim 12 in which said sintered metal is selected from the group consisting of tungsten, nickel, tantalum, molybdenum, cobalt and sintered tungsten body infiltrated by a copper based alloy.

Claim 16

Claim 16. A temperature stable diamond product as set forth in claim 1 wherein said diamond piece is composed of at least 60% by volume of diamond aggregates.

Claim 17

Claim 17. A temperature stable diamond product having a temperature stability up to about 1,200 degrees C. comprising: a metal matrix carrier selected from the group consisting of tungsten metal powder and the carbides of tungsten, titanium, tantalum and molybdenum, at least one diamond piece of a predetermined geometrical shape and which is temperature stable up to about 1,200 degrees C. at least some of which have at least one surface contacting at least a portion of said carrier, said diamond being a polycrystalline diamond composed of at least 60% by volume of diamond aggregates, each diamond piece being coated with a metal which is a carbide former on at least the portion thereof contacting said metal matrix carrier, said coating on said temperature stable diamond having a thickness of at least about one micron and including a carbide layer which is of a thickness of less than about 20 microns, said carbide former being a metal selected from the group consisting of Groups IVA, VA, VIA and VIIA metals and alloys and mixtures thereof, and said temperature stable diamond product being characterized by a chemical bond between said temperature stable diamond and said coating and said coating and the portion of said matrix carrier which is in contact with said coating.

Claim 18

Claim 18. A temperature stable diamond product as set forth in claim 17 which includes a plurality of initially separate temperature stable diamond elements arranged in a predetermined relationship and including opposed surface portions forming a gap therebetween, said gap being in the range of between less than 1 mil and 500 mils, and said matrix carrier being located in said gap and contacting at least a portion of the surface portions of said temperature stable diamond elements.

Claim 19

Claim 19. A temperature stable diamond product as set forth in claim 17 in which said product is a saw blade segment.

Claim 20

Claim 20. A temperature stable diamond product as set forth in claim 17 in which said product is a bearing element.

Claim 21

Claim 21. A temperature stable diamond product as set forth in claim 17 in which said product is a dressing tool.

Claim 22

Claim 22. A temperature stable diamond product as set forth in claim 17 in which said product is a cutter adapted to be mounted on an earth boring bit.

Claim 23

Claim 23. A temperature stable diamond product as set forth in claim 17 in which said product is a component of a twist drill.

Claim 24

Claim 24. A temperature stable diamond product as set forth in claim 17 in which said product is a lead bonding tool.

Claim 25

Claim 25. A temperature stable diamond product as set forth in claim 17 in which said product is a single point dressing tool.

Claim 26

Claim 26. In an earth boring bit including a body, the improvement comprising: at least one cutter element supported by said body, said cutter element including at least one polycrystalline diamond element which is temperature stable to at least about 1,200 degrees C. supported by a carrier matrix, said temperature stable diamond element having a coating thereon at least on that surface thereof which is in contact with said carrier matrix, said coating including being of a thickness of at least about 1 micron and including a relatively thin carbide layer adjacent to said surface, and said temperature stable diamond element being bonded to the contacting portion of said matrix carrier by a chemical bond between said temperature stable diamond element and said coating and said coating and the portion of said matrix carrier which is in contact with said coating.

Claim 27

Claim 27. An earth boring bit as set forth in claim 26 wherein said cuter element includes a plurality of polycrystalline diamond elements.

Claim 28

Claim 28. An earth boring bit as set forth in claim 26 wherein said body includes a surface of matrix carrier material.

Claim 29

Claim 29. An earth boring bit as set forth in claim 27 wherein at least some of said polycrystalline diamond elements are triangular in shape.

Claim 30

Claim 30. An earth boring bit as set forth in claim 26 wherein said polycrystalline diamond element is in the form of a facing on said carrier matrix and chemically bonded thereto.

Claim 31

Claim 31. An earth boring bit as set forth in claim 26 wherein said cutter element is of a diameter greater than 14mm.

Claim 32

Claim 32. An earth boring bit as set forth in claim 26 in which said bit includes a plurality of said cutter elements.

Claim 33

Claim 33. A temperature stable diamond product having a temperature stability up to about 1,200 degrees C. comprising: a metal matrix carrier including a powdered material and a binder therefor, a plurality of diamond pieces of a predetermined geometrical shape each of which is temperature stable up to about 1,200 degrees C. and at least some of which have at least one surface contacting at least a portion of said carrier, at least some of said diamond pieces being in butting relation with an adjacent diamond piece, each diamond piece being coated with a metal which is a carbide former on at least the portion thereof contacting said metal matrix carrier and on the surface portion which is adjacent to another diamond piece, the coating on said diamond piece being at least about 3 microns in thickness, and said temperature stable diamond product being characterized by a chemical bond between said temperature stable diamond and said coating and said coating and the binder for said matrix carrier which is in contact with said coating.

Claim 34

Claim 34. A method of forming a temperature stable diamond product having a temperature stability of up to about 1,200 degrees C. from at least one initially separate temperature stable diamond element of a predetermined geometric shape, comprising the steps of: coating at least a portion of the surface of said temperature stable diamond element with a metallic carbide former, said coating being of a thckness of at least about 3 microns, assembling with said coating temperature stable diamond element a matrix carrier powder such that the powder contacts at least the coated surface of said temperature stable diamond, cold pressing said assembled owder and said temperature stable diamond to compact said powder to a volume density of more than 40% to form a cold pressed intermediate, cold isostatic pressing said cold pressed intermediate to compact said powder to a volume density of greater than 50% to provide an isostatic pressed intermediate, and heating said isostatic pressed intermediate at an elevated temperature and in a controlled atmosphere for a period of time sufficient form of a chemical bond between the coating on the surface of said temperature stable diamond element and said diamond element and between said coating and the matrix carrier material in contact with said coating.

Claim 35

Claim 35. A method as set forth in Claim 34 wherein heating of said isostatic pressed intermediate includes heating at a rate not greater than about 10 degrees C. per minute in the range of between about 900 degrees C. and 1,100 degrees C. to effect conversion of a portion of said carbide forming coating to a carbide.

Claim 36

Claim 36. A method as set forth in Claim 34 wherein said matrix carrier powder is a mixture of a carbide and a binder therefor.

Claim 37

Claim 37. A method as set forth in Claim 34 wherein said assembly step includes the assembly of a plurality of coated temperature stable diamond elements in a predetermined configuration.

Claim 38

Claim 38. A method as set forth in Claim 37 wherein said elements are assembled such that there is a gap between adjacent elements.

Claim 39

Claim 39. A method as set forth in Claim 37 wherein said elements are assembled such that at least some of them are in butting relation.

Claim 40

Claim 40. A method as set forth in Claim 34 wherein said metallic carbide former is a metal selected from the group consisting of the metals of Group IVA, VA, VIA,VII and alloys and mixtures thereof.

Claim 41

Claim 41. A method as set forth in Claim 34 further including the step of assembling said isostatic pressed intermediate to a powdered support material, and said heating operation including heating the isostatic pressed intermediate and said powdered material to effect the chemical bonding and to effect formation of said powdered material into a support for said temperature stable synthetic diamond element.