Methods of forming polycrystalline bodies using rhombohedral graphite materials

• US 20060251567A1
• Filed: 04/04/2006
• Published: 11/09/2006
• Est. Priority Date: 07/25/2003
• Status: Abandoned Application

• Current Assignee: Chien-Min Sung
• Original Assignee: Chien-Min Sung
• Inventors: Sung, Chien-Min
• Application Number:
  US11/398,468
• Publication Number:
  US 20060251567A1
• Time in Patent Office: Days
• US Class Current: 423/446
• CPC Class Codes: B01J 2203/0625 Carbon
• CPC Class Codes: B01J 2203/0645 Boronitrides
• CPC Class Codes: B01J 2203/0655 Diamond
• CPC Class Codes: B01J 2203/066 Boronitrides
• CPC Class Codes: B01J 3/062 characterised by the composition of the materials to be processed
• CPC Class Codes: B01J 3/065 Presses for the formation of diamonds or boronitrides
• CPC Class Codes: B01J 3/08 Application of shock waves for chemical reactions or for modifying the crystal structure of substances

Abstract

Methods of synthesizing polycrystalline bodies using rhombohedral graphite materials are disclosed and described. One procedure includes providing a particulate graphite source having a majority of carbon atoms oriented in a rhombohedral polytype configuration. The particulate graphite source can be shaped into a desired shape having a porosity from about 0% to about 30%. A sufficient amount of heat and pressure can be applied to the desired shape to form diamond and consolidate the diamond into a polycrystalline body.

Claims

1. A method of making a polycrystalline diamond body comprising:

a) providing a particulate graphite source having a majority of carbon atoms oriented in a rhombohedral polytype configuration;

b) shaping the particulate graphite source into a desired shape for the polycrystalline diamond body, said desired shape having a porosity from about 0% to about 30%; and

c) applying a sufficient amount of heat and pressure to the graphite source to convert the graphite particles to diamond and to consolidate the diamond particles into the polycrystalline diamond body.

2. The method of claim 1, wherein at least about 80% of the carbon atoms of the graphite source are oriented in a rhombohedral polytype configuration.

3. The method of claim 1, wherein the carbon atoms of the graphite source are substantially all oriented in a rhombohedral polytype configuration.

4. The method of claim 1, wherein the rhombohedral graphite is provided by dissolving carbon in a molten metal, solidifying the molten metal, and harvesting the rhombohedral graphite from the metal.

5. The method of claim 4, wherein the metal comprises a member selected from the group consisting of Fe, Co, Ni, Mn, Cr, and semi-alloys or alloys thereof.

6. The method of claim 5, wherein the metal comprises Fe.

7. The method of claim 4, wherein the carbon is added to the molten metal in an amount that is sufficient to substantially saturate the metal with the carbon.

8. The method of claim 4, wherein the rhombohedral graphite is harvested from the solidified molten metal using an acid.

9. The method of claim 1, wherein the graphite particles are shaped into the desired shape using a mold.

10. The method of claim 1, wherein the desired shape has a porosity of less than about 15%.

11. The method of claim 1, further comprising adding a binder agent to the graphite particles prior to heating and pressing the particles.

12. The method of claim 11, wherein the binder agent is Co.

13. A polycrystalline diamond body formed by the method of claim 1.