Superabrasive Particle Synthesis with Controlled Placement of Crystalline Seeds

• US 20080248305A1
• Filed: 03/31/2008
• Published: 10/09/2008
• Est. Priority Date: 04/04/1997
• Status: Abandoned Application

• Current Assignee: Chien-Min Sung
• Original Assignee: Chien-Min Sung
• Inventors: Sung, Chien-Min
• Application Number:
  US12/059,422
• Publication Number:
  US 20080248305A1
• Time in Patent Office: Days
• US Class Current: 428/403
• CPC Class Codes: B01J 2203/061 Graphite
• CPC Class Codes: B01J 2203/062 Diamond
• 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 2203/068 Crystal growth
• 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: B22F 1/05 Metallic powder characterised by the size or surface area of the particles
• CPC Class Codes: B22F 2003/1046 with separating means for articles to be sintered
• CPC Class Codes: B22F 2005/001 Cutting tools, earth boring or grinding tool other than table ware
• CPC Class Codes: B22F 2207/03 of the metallic binder phase in cermets
• CPC Class Codes: B22F 2999/00 Aspects linked to processes or compositions used in powder metallurgy
• CPC Class Codes: B22F 3/004 Filling molds with powder feeding material to presses in general B30B15/302
• CPC Class Codes: B23D 61/18 Sawing tools of special type, e.g. wire saw strands, saw blades or saw wire equipped with diamonds or other abrasive particles in selected individual positions cut-off wheels of bonded abrasive or with inserted abrasive blocks B24D5/12
• CPC Class Codes: B23D 65/00 Making tools for sawing machines or sawing devices for use in cutting any kind of material
• CPC Class Codes: B23P 15/28 cutting tools sawing tools B23D63/00, B23D65/00; files or rasps B23D73/00
• CPC Class Codes: B24D 18/00 Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
• CPC Class Codes: B24D 2203/00 Tool surfaces formed with a pattern
• CPC Class Codes: B24D 3/08 : for close-grained structure, e.g. using metal with low melting point
• CPC Class Codes: B24D 7/066 : Grinding blocks; their mountings or supports
• CPC Class Codes: B24D 99/005 : Segments of abrasive wheels
• CPC Class Codes: C04B 35/52 : based on carbon, e.g. graphite
• CPC Class Codes: C09K 3/1409 : Abrasive particles per se preparation of diamond C01B32/25
• CPC Class Codes: C09K 3/1445 : the coating consisting exclusively of metals
• CPC Class Codes: C22C 1/051 : Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor
• CPC Class Codes: C22C 2204/00 : End product comprising different layers, coatings or parts of cermet
• CPC Class Codes: C22C 26/00 : Alloys containing diamond or cubic or wurtzitic boron nitride, fullerenes or carbon nanotubes
• CPC Class Codes: E21B 10/5676 : having a cutting face with different segments, e.g. mosaic-type inserts
• CPC Class Codes: Y10T 428/2991 : Coated

Abstract

An improved method for synthesizing superabrasive particles provides high quality industrial superabrasive particles with high yield and a narrow size distribution. The synthesis method can include forming a growth precursor of a substantially homogeneous mixture of raw material and catalyst material or layers of raw material and metal catalyst. The growth precursor can have a layer of adhesive over at least a portion thereof. A plurality of crystalline seeds can be placed in a predetermined pattern on the layer of adhesive. The growth precursor can be maintained at a temperature and pressure at which the superabrasive crystal is thermodynamically stable for a time sufficient for a desired degree of growth. Advantageously, the patterned placement of crystalline seeds and disclosed processes allow for production of various morphologies of synthetic diamonds, including octahedral and cubic diamonds, and improved growth conditions generally. As a result, the grown superabrasive particles typically have a high yield of high quality particles and a narrow distribution of particle sizes.

Claims

1. An unsorted collection of superabrasive particles produced by the steps of:

a) forming at least a portion of a growth precursor, said growth precursor including a raw material and a particulate catalyst material;

b) arranging crystalline seeds in a predetermined pattern on a layer of adhesive, said layer of adhesive being coated over at least a portion of a surface of the growth precursor; and

c) heating the growth precursor under temperature and pressure conditions sufficient to grow superabrasive particles having a preselected morphology, wherein said unsorted collection is obtained by recovering the superabrasive particles subsequent to the step of heating and without sizing or sorting of the superabrasive particles.

2. The unsorted collection of claim 1, wherein said superabrasive particles have a narrow size distribution characterized by a standard deviation of less than about 0.05 of an average size.

3. The unsorted collection of claim 1, wherein said superabrasive particles have fewer than 1 wt % inclusions.

4. An unsorted collection of superabrasive particles, comprising a plurality of superabrasive particles having a narrow size distribution characterized by greater than 95% of the superabrasive particles having a size within about 20% of an average size.

5. The unsorted collection of claim 4, wherein greater than about 70% of the superabrasive particles are cubic.

6. The unsorted collection of claim 4, wherein greater than about 70% of the superabrasive particles are octahedral.