Polycrystalline diamond cutting elements having non-catalyst material additions
View Patent ↗Polycrystalline diamond cutting elements having enhanced thermal stability, drill bits incorporating the same, and methods of making the same are disclosed herein. In one embodiment, a cutting element includes a substrate having a metal carbide and a polycrystalline diamond body bonded to the substrate. The polycrystalline diamond body includes a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds and a plurality of interstitial regions positioned between adjacent diamond grains. At least a portion of the plurality of interstitial regions comprise a non-catalyst material, a catalyst material, metal carbide, or combinations thereof. At least a portion of the plurality of interstitial regions comprise non-catalyst material that coats portions of the adjacent diamond grains such that the non-catalyst material reduces contact between the diamond and the catalyst.
1. A cutting element, comprising:
a substrate comprising a metal carbide; and
a polycrystalline diamond body bonded to the substrate, the polycrystalline diamond body comprising a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds and a plurality of interstitial regions positioned between adjacent diamond grains,
wherein at least a portion of the plurality of interstitial regions comprises a non-catalyst material having more than 0.1 wt % lead and having less than about 10 wt. % lead, which coats portions of the adjacent diamond and reduces contact between the diamond and a catalyst.
2. The cutting element of claim 1 , wherein at least a portion of the plurality of interstitial regions are substantially free of non-catalyst material and catalyst material.
3. The cutting element of claim 2 , wherein the portion of the plurality of interstitial regions that are substantially free of non-catalyst material and catalyst material are subject to a leaching process.
4. The cutting element of claim 1 , wherein portions of the catalyst material that is positioned within the interstitial regions are spaced apart from the diamond grains by the non-catalyst material.
5. The cutting element of claim 1 , wherein the diamond grains have higher wettability with the catalyst material than the non-catalyst material when both are molten.
6. The cutting element of claim 1 , wherein when the non-catalyst material and the catalyst material are held at a temperature above the melting or liquid temperature of the catalyst material, the non-catalyst material has a lower viscosity than the catalyst material.
7. The cutting element of claim 1 wherein the plurality of interstitial regions comprises a non-catalyst material having more than 0.1 wt % lead and having less than 3.0 wt % of lead.
8. The cutting element of claim 1 wherein the plurality of interstitial regions comprises a non-catalyst material having more than 0.1 wt % lead and having less than 1.0 wt % of lead.
9. The cutting element of claim 1 wherein the plurality of interstitial regions comprises a non-catalyst material having more than about 1.0 wt % of lead and less than about 3.0 wt % of lead.
10. A polycrystalline diamond volume comprising:
a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds forming a continuous diamond matrix and a plurality of interstitial regions positioned between adjacent diamond grains and forming a continuous interstitial matrix,
wherein at least a portion of the continuous interstitial matrix comprises a catalyst material that is separated from the diamond grains by a non-catalyst material,
wherein the non-catalyst material has more than 0.1 wt % lead and has less than about 10 wt. % lead, and
wherein the non-catalyst material coats portions of the diamond grains such that the non-catalyst material reduces contact between the diamond grains and the catalyst material.
11. The cutting element of claim 10 , wherein at least a portion of the plurality of interstitial regions are substantially free of the non-catalyst material and the catalyst material.
12. The cutting element of claim 11 , wherein the portion of the plurality of interstitial regions that are substantially free of the non-catalyst material and the catalyst material were subjected to a leaching process.
13. The cutting element of claim 10 , wherein the diamond grains have higher wettability with the catalyst material than the non-catalyst material when both are molten.
14. A cutting element comprising:
a substrate comprising a metal carbide; and
a polycrystalline diamond body bonded to the substrate, the polycrystalline diamond body comprising a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds forming a continuous diamond matrix and a plurality of interstitial regions positioned between adjacent diamond grains and forming a continuous interstitial matrix,
wherein at least a portion of the continuous interstitial matrix comprises a catalyst material that is separated from the diamond grains by a non-catalyst material,
wherein the non-catalyst material has more than 0.1 wt % lead and has less than about 10 wt. % lead, and
wherein the non-catalyst material coats portions of the diamond grains such that the non-catalyst material reduces contact between the diamond grains and the catalyst material.
15. A method of forming a cutting element, comprising:
assembling a reaction cell comprising a plurality of diamond particles, a non-catalyst material having more than 0.1 wt % lead and less than about 10 wt % lead, a catalyst material, and a substrate within a refractory metal container; and
subjecting the reaction cell and its contents to a high pressure high temperature sintering process to form a continuous diamond volume in which:
the diamond particles are compacted into a densified unbonded diamond region in which at least some of the diamond particles are separated by interstitial regions;
the non-catalyst material is melted and is present in a liquid state in at least some of the interstitial regions between diamond particles; and
the catalyst material is melted and is present in at least some of the interstitial regions between the individual diamond grains, wherein the catalyst material promotes formation of diamond-to-diamond bonds between adjacent diamond particles,
wherein the non-catalyst material coats surfaces of at least a portion of the plurality of diamond particles after the high pressure high temperature sintering operation is completed such that the non-catalyst material reduces contact between the diamond grains and the catalyst material.
16. The method of claim 15 , wherein the catalyst material is swept through at least a portion of the plurality of unbonded diamond particles while molten and displaces a portion of the non-catalyst material from the interstitial regions between diamond particles.
17. The method of claim 15 , wherein the non-catalyst material is swept through at least a portion of the plurality of unbonded diamond particles while molten.
18. The method of claim 15 , wherein the non-catalyst material is mixed with the diamond particles prior to the step of compaction of the diamond particles.
19. The method of claim 15 , wherein the volume of non-catalyst material introduced to the diamond particles is less than a volume of interstitial regions between diamond particles.
20. The method of claim 15 , wherein when the non-catalyst material and the catalyst material are held at a temperature above the melting or liquid temperature of the catalyst material, the non-catalyst material has a lower viscosity than the catalyst material.
21. The method of claim 15 , further comprising subjecting the diamond volume to a leaching process in which a leaching agent removes at least portions of the catalyst material and non-catalyst material from the interstitial regions of the diamond volume.
22. The method of claim 15 , wherein the diamond grains have higher wettability with the catalyst material than the non-catalyst material when both are molten.
23. A drill bit comprising:
a material removal portion having a plurality of shanks, the material removal portion having an axis of rotation that is relative to a base portion; and
at least one cutting element that is bonded to the material removal portion at one of the plurality of shanks, the cutting elements comprising:
a substrate comprising a metal carbide; and
a polycrystalline diamond body bonded to the substrate, the polycrystalline diamond body comprising a plurality of diamond grains bonded to adjacent diamond grains by diamond-to-diamond bonds and a plurality of interstitial regions positioned between adjacent diamond grains,
wherein at least a portion of the plurality of interstitial regions comprise non-catalyst material having more than 0.1 wt % lead and less than about 10 wt. % lead, which coats portions of the adjacent grains and reduces contact between the diamond and a catalyst material.
24. The cutting element of claim 23 wherein the plurality of interstitial regions comprises a non-catalyst material having more than 0.1 wt % lead and having less than 3.0 wt % of lead.
25. The cutting element of claim 23 wherein the plurality of interstitial regions comprises a non-catalyst material having more than 0.1 wt % lead and having less than 1.0 wt % of lead.
26. The cutting element of claim 23 wherein the plurality of interstitial regions comprises a non-catalyst material having about 1.0 wt % of lead.