Superabrasive materials, methods of fabricating same, and applications using same
View Patent ↗Embodiments of the present invention relate to superabrasive materials, superabrasive compacts employing such superabrasive materials, and methods of fabricating such superabrasive materials and compacts. In one embodiment, a superabrasive material includes a matrix comprising a plurality of coarse-sized superabrasive grains, with the coarse-sized superabrasive grains exhibiting a coarse-sized average grain size. The superabrasive material further includes a plurality of superabrasive regions dispersed within the matrix, with each superabrasive region including a plurality of fine-sized superabrasive grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size. In another embodiment, the superabrasive materials may be employed in a superabrasive compact. The superabrasive compact comprises a substrate including a superabrasive table comprising any of the disclosed superabrasive materials. Further embodiments are directed to applications utilizing the disclosed superabrasive articles in applications, such as rotary drill bits.
1. A superabrasive material, comprising:
a matrix including a plurality of coarse-sized superabrasive grains, the coarse-sized superabrasive grains exhibiting a coarse-sized average grain size of about 6 μm to about 20 μm; and a plurality of superabrasive regions dispersed within the matrix, each of the superabrasive regions including a plurality of fine-sized superabrasive grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size, each of the superabrasive regions exhibiting an average size of about 50 μm to about 200 μm.
2. The superabrasive material of claim 1 wherein the matrix comprises a substantially continuous matrix.
3. The superabrasive material of claim 1 wherein each of the superabrasive regions exhibits an average size that is greater than the coarse-sized average grain size.
4. The superabrasive material of claim 1 wherein the fine-sized average grain size of each of the superabrasive regions is about 6 μm or less.
5. The superabrasive material of claim 1 wherein the coarse-sized average grain size of the matrix is about 5 times or more than the fine-sized average grain size of the superabrasive regions.
6. The superabrasive material of claim 1 wherein each of the superabrasive regions exhibits a generally cylindrical geometry or a generally ellipsoid geometry.
7. The superabrasive material of claim 1 wherein:
the coarse-sized superabrasive grains of the matrix comprise polycrystalline diamond, polycrystalline boron nitride, or mixtures thereof; and each of the superabrasive regions comprises polycrystalline diamond, polycrystalline boron nitride, tungsten carbide, silicon carbide, or mixtures thereof.
8. The superabrasive material of claim 1 wherein:
the plurality of coarse-sized superabrasive grains defines a plurality of first interstitial regions; the plurality of fine-sized superabrasive grains defines a plurality of second interstitial regions; and the first and second interstitial regions include metal-solvent catalyst disposed therein.
9. The superabrasive material of claim 8 wherein the metal-solvent catalyst comprises cobalt, nickel, iron, or alloys thereof.
10. The superabrasive material of claim 8 wherein at least a portion of the first and the second interstitial regions are substantially free of the metal-solvent catalyst.
11. A superabrasive compact, comprising:
a superabrasive table comprising: a matrix including a plurality of coarse-sized superabrasive grains, the coarse-sized superabrasive grains exhibiting a coarse-sized average grain size of about 6 μm to about 20 μm; and a plurality of superabrasive regions dispersed within the matrix, each of the superabrasive regions including a plurality of fine-sized superabrasive grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size, each of the superabrasive regions exhibiting an average size of about 50 μm to about 200 μm; and a substrate bonded to the superabrasive table.
12. The superabrasive compact of claim 11 wherein the substrate comprises a binderless carbide material or a cemented-carbide material.
13. A method, comprising:
providing a plurality of coarse-sized superabrasive particles, the coarse-sized superabrasive particles exhibiting a coarse-sized average particle size; forming a plurality of agglomerates, each of the agglomerates including a plurality of fine-sized superabrasive particles exhibiting a fine-sized average particle size less than the coarse-sized average particle size; mixing the plurality of agglomerates with the plurality of coarse-sized superabrasive particles to form a mixture; and sintering the mixture to form a superabrasive material.
14. The method of claim 13 wherein sintering the mixture to form a superabrasive material comprises: exposing the mixture to at least about 40 kilobar; and heating the mixture to at least about 1000° Celsius.
15. The method of claim 13 wherein forming a plurality of agglomerates comprises at least one of freeze drying, spray-drying, or sieve granulating the plurality of fine-sized superabrasive particles to form the plurality of agglomerates.
16. The method of claim 13 , further comprising: selecting each of the agglomerates to exhibit an average size that is greater than the coarse-sized average particle size of the plurality of coarse-sized superabrasive particles.
17. The method of claim 13 , further comprising: forming each of the agglomerates to exhibit an average size of about 50 μm to about 200 μm; and selecting the coarse-sized average particle size of the plurality of coarse-sized superabrasive particles to be about 6 μm to about 20 μm.
18. The method of claim 13 , further comprising: selecting the coarse-sized average particle size of the plurality of coarse-sized superabrasive particles to be about 10 μm to about 30 μm; and selecting the fine-sized average particle size of each of the agglomerates to be about 6 μm or less.
19. The method of claim 13 , further comprising: forming each of the agglomerates to exhibit a generally cylindrical geometry or a generally ellipsoid geometry.
20. The method of claim 13 , further comprising: prior to the act of sintering the mixture to form the superabrasive material, positioning the mixture adjacent to a substrate.
21. A method, comprising:
forming a plurality of agglomerates by at least one of freeze drying, spray-drying, or sieve granulation, each of the agglomerates including a plurality of fine-sized superabrasive particles exhibiting a fine-sized average particle size; mixing the plurality of agglomerates with a plurality of coarse-sized superabrasive particles to form a mixture, the coarse-sized superabrasive particles exhibiting a coarse-sized average particle size greater than the fine-sized average particle size; and sintering the mixture to form a superabrasive material.
22. The method of claim 21 wherein mixing the plurality of agglomerates with a plurality of coarse-sized superabrasive particles to form a mixture comprises mixing the plurality of agglomerates with the plurality of coarse-sized superabrasive particles so that the plurality of agglomerates do not substantially break apart during the mixing.