Rotary drill bit employing polycrystalline diamond cutting elements
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 rotary drill bit, comprising:
a bit body configured for drilling a subterranean formation, the bit body including a plurality of blades, each of the plurality of blades having a plurality of polycrystalline diamond cutting elements affixed thereto, at least one of the plurality of polycrystalline diamond cutting elements including:
a polycrystalline diamond table including:
a matrix including a plurality of coarse-sized diamond grains, the coarse-sized diamond grains exhibiting a coarse-sized average grain size of at least about 6 μm and at least a bimodal grain size distribution; and
a plurality of polycrystalline diamond regions dispersed within the matrix, at least a portion of the polycrystalline diamond regions including a plurality of fine-sized polycrystalline diamond grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size, each of the at least a portion of the polycrystalline diamond regions exhibiting an average size of at least about 50 μm; and
a substrate bonded to the polycrystalline diamond table.
2. The rotary drill bit of claim 1 wherein the average size of each of the at least a portion of the polycrystalline diamond regions is greater than the coarse-sized average grain size.
3. The rotary drill bit of claim 1 wherein the fine-sized average grain size of each of the at least a portion of the polycrystalline diamond regions is about 6 μm or less.
4. The rotary drill bit 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 plurality of polycrystalline diamond regions.
5. The rotary drill bit of claim 1 wherein the coarse-sized average grain size of the plurality of coarse-sized diamond grains is about 6 μm to about 30 μm.
6. The rotary drill bit of claim 1 wherein the coarse-sized average grain size of the plurality of coarse-sized diamond grains is about 6 μm to about 20 μm.
7. The rotary drill bit of claim 1 wherein:
the plurality of coarse-sized diamond grains define a plurality of first interstitial regions;
the plurality of fine-sized diamond grains define a plurality of second interstitial regions; and
at least a portion of the first and second interstitial regions include metal-solvent catalyst disposed therein.
8. The rotary drill bit of claim 7 wherein at least a portion of the first and the second interstitial regions are substantially free of the metal-solvent catalyst.
9. The rotary drill bit of claim 1 wherein the polycrystalline diamond table is pre-sintered.
10. The rotary drill bit of claim 1 wherein the polycrystalline diamond table is integrally formed with the substrate.
11. The rotary drill bit of claim 1 wherein the substrate comprises a cemented carbide material including iron, nickel, cobalt, or alloys thereof.
12. A rotary drill bit, comprising:
a bit body configured for drilling a subterranean formation, the bit body including a plurality of blades, each of the plurality of blades having a plurality of polycrystalline diamond cutting elements affixed thereto, at least one of the plurality of polycrystalline diamond cutting elements including:
at least one region including a plurality of coarse-sized diamond grains, the coarse-sized diamond grains exhibiting a coarse-sized average grain size of at least about 6 μm and at least a bimodal grain size distribution; and
a plurality of polycrystalline diamond regions dispersed through the at least one region, at least a portion of the polycrystalline diamond regions including a plurality of fine-sized polycrystalline diamond grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size, each of the at least a portion of the polycrystalline diamond regions exhibiting an average size of at least about 50 μm.
13. A rotary drill bit, comprising:
a bit body configured for drilling a subterranean formation, the bit body including a plurality of blades, each of the plurality of blades having a plurality of polycrystalline diamond cutting elements affixed thereto, at least one of the plurality of polycrystalline diamond cutting elements including:
a matrix including a plurality of coarse-sized diamond grains, the coarse-sized diamond grains exhibiting a coarse-sized average grain size of at least about 6 μm; and
a plurality of polycrystalline diamond regions dispersed within the matrix, at least a portion of the polycrystalline diamond regions including a plurality of fine-sized polycrystalline diamond grains exhibiting a fine-sized average grain size less than the coarse-sized average grain size, each of the at least a portion of the polycrystalline diamond regions exhibiting an average size of about 50 μm to about 200 μm; and
a substrate bonded to the polycrystalline diamond table.
14. The rotary drill bit of claim 13 wherein the average size of each of the at least a portion of the polycrystalline diamond regions is greater than the coarse-sized average grain size.
15. The rotary drill bit of claim 13 wherein the fine-sized average grain size of each of the at least a portion of the polycrystalline diamond regions is less than 6 μm.
16. The rotary drill bit of claim 13 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 plurality of polycrystalline diamond regions.
17. The rotary drill bit of claim 13 wherein the coarse-sized average grain size of the plurality of coarse-sized diamond grains is about 6 μm to about 30 μm.
18. The rotary drill bit of claim 13 wherein the coarse-sized average grain size of the plurality of coarse-sized diamond grains is about 6 μm to about 20 μm.
19. The rotary drill bit of claim 13 wherein the polycrystalline diamond table is pre-sintered.
20. The rotary drill bit of claim 13 wherein the polycrystalline diamond table is integrally formed with the substrate.