Compact of boron-doped diamond and method for making same

• US 4,268,276 A
• Filed: 02/13/1979
• Issued: 05/19/1981
• Est. Priority Date: 04/24/1978
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bovenkerk, Harold P.
• Primary Examiner(s): Arnold, Donald J.
• Application Number:
  US06/011,771
• Time in Patent Office: 826 Days
• Field of Search: 51/295, 51/307, 51/308, 51/309, 264/320, 264/332
• US Class Current: 51/295
• CPC Class Codes: B01J 2203/062 Diamond
• CPC Class Codes: B01J 2203/0655 Diamond
• CPC Class Codes: B01J 2203/0685 Crystal sintering
• CPC Class Codes: B01J 3/062 characterised by the composition of the materials to be processed
• CPC Class Codes: B23B 27/20 with diamond bits or cutting inserts
• CPC Class Codes: C04B 2235/656 characterised by specific heating conditions during heat treatment
• CPC Class Codes: C04B 2235/6567 Treatment time
• CPC Class Codes: C04B 2235/6582 Hydrogen containing atmosphere
• CPC Class Codes: C04B 2237/12 Metallic interlayers
• CPC Class Codes: C04B 2237/123 based on iron group metals, e.g. steel
• CPC Class Codes: C04B 2237/363 Carbon
• CPC Class Codes: C04B 2237/401 Cermets
• CPC Class Codes: C04B 2237/405 Iron metal group, e.g. Co or Ni
• CPC Class Codes: C04B 2237/61 Joining two substrates of which at least one is porous by infiltrating the porous substrate with a liquid, such as a molten metal, causing bonding of the two substrates, e.g. joining two porous carbon substrates by infiltrating with molten silicon
• CPC Class Codes: C04B 2237/765 at least one member being a tube
• CPC Class Codes: C04B 2237/84 Joining of a first substrate with a second substrate at least partially inside the first substrate, where the bonding area is at the inside of the first substrate, e.g. one tube inside another tube
• CPC Class Codes: C04B 35/6303 Inorganic additives
• CPC Class Codes: C04B 35/645 Pressure sintering
• CPC Class Codes: C04B 35/6455 Hot isostatic pressing
• CPC Class Codes: C04B 37/021 in a direct manner, e.g. direct copper bonding [DCB]
• CPC Class Codes: C04B 37/026 : consisting of metals or metal salts

Abstract

In one embodiment, a compact for tools, such as cutting, drilling, wire drawing and shaping tools, consists essentially of a porous mass of self-bonded, boron-doped diamond particles and a catalyst-solvent material. The method for making such a compact comprises the steps of bonding a mass of boron-doped diamond particles, aided by a catalyst-solvent material, under high temperatures and high pressures (HP/HT).

In another embodiment, a composite compact, which is made in a similar manner to the first embodiment, consists essentially of (i) a layer of a porous mass of self-bonded, boron-doped diamond particles and catalyst-solvent material; and (ii) a substrate layer of cemented carbide bonded to the diamond layer.

Claims

1. In a process for making a compact comprising:

(a) placing within a charge assembly (i) a mass comprised of diamond particles and (ii) a source of diamond catalyst-solvent material; and

(b) subjecting said charge assembly and the contents thereof to thermodynamically stable conditions for the diamond content thereof at temperatures in the range of 1300°

C. to 1600°

C. and pressures in excess of about 45 kilobars;

the improvement which comprises using boron doped diamond particles in step (a).

2. The process of claim 1 wherein said source of diamond catalyst-solvent is cemented carbide.

3. The process of claim 1 wherein said source of diamond catalyst-solvent is carbide molding powder.

4. The process of claim 1 wherein said source of diamond catalyst-solvent is a metal shim.

5. The process of claim 1 wherein said catalyst-solvent material is selected from the group consisting of:

(a) a catalytic metal, in elemental form, selected from the group consisting of Group VIII metals Cr, Mn, Ta;

(b) a mixture of alloyable metals of the catalytic metal(s) and non-catalytic metal(s);

(c) an alloy of at least two of said catalytic metals; and

(d) an alloy of the catalytic metal(s) and non-catalytic metal(s).

6. The process of claim 1 wherein the level of the boron dopant in said particles is between about 0.01% and 0.5% of the weight of the doped particles.

7. The process of claim 1 wherein said mass is at least 70% by volume diamond.

8. The process of claim 1 wherein said mass is at least 90% by volume diamond.

9. A compact comprised of a mass of self-bonded diamond particles doped with boron atoms distributed substantially uniformly throughout each of said particles.

10. The compact of claim 9 wherein said mass is porous.

11. The compact of claim 10 which further comprises a catalyst-solvent material dispersed in the pores of said mass.

12. The compact of claim 11 wherein said catalyst-solvent material is selected from the group consisting of:

(a) a catalytic metal, in elemental form, selected from the group consisting of Group VIII metals Cr, Mn, Ta;

(b) a mixture of alloyable metals of the catalytic metal(s) and non-catalytic metal(s);

(c) an alloy of at least two of said catalytic metals; and

(d) an alloy of the catalytic metal(s) and non-catalytic metal(s).

13. The compact of claim 9 further comprising a mass of cemented carbide, said carbide bonded to said compact along an interface.

14. The compact of claim 9 wherein said mass is at least 90% by volume diamond.

15. The compact of claim 9 wherein said particles are boron-doped to a level between about 0.01% to 0.5% of the doped particle weight.

16. A compact comprising:

(a) a porous mass of self-bonded, boron-doped diamond particles, said mass comprising at least 90% by volume diamond, said particles containing a boron-dopant level between about 0.01% to 0.5% of the doped particle weight; and

(b) a catalyst-solvent material dispersed in the pores of said mass, said material selected from the group consisting of;

(i) a catalytic metal, in elemental form, selected from the group consisting of Group VIII metals Cr, Mn, Ta;

(ii) a mixture of alloyable metals of the catalytic metal(s) and non-catalytic metal(s);

(iii) an alloy of at least two of said catalytic metals; and

(iv) an alloy of the catalytic metal(s) and non-catalytic metal(s).

17. A compact comprised of:

(a) a porous mass of self-bonded, boron-doped diamond particles; and

(b) a catalyst-solvent material dispersed in the pores of said mass.

18. The compact of claim 17 wherein said material is selected from the group consisting of:

(a) a catalytic metal, in elemental form, selected from the group consisting of Group VIII metals Cr, Mn, Ta;

(b) a mixture of alloyable metals of the catalytic metal(s) and non-catalytic metal(s);

(c) an alloy of at least two of said catalytic metals; and

(d) an alloy of the catalytic metal(s) and non-catalytic metal(s).

19. The compact of claim 17 further comprising a mass of cemented carbide, said carbide bonded to said compact along an interface.

20. The compact of claim 17 wherein said mass is at least 90% by volume diamond.

21. The compact of claim 17 wherein said particles are boron-doped to a level between about 0.01% to 0.5% of the doped particle weight.