Polycrystalline diamond insert, drill bit including same, and method of operation
View Patent ↗Polycrystalline diamond inserts are disclosed. For example, a polycrystalline diamond insert may comprise a polycrystalline diamond layer affixed to a substrate at an interface. In addition the polycrystalline diamond layer may comprise: an arcuate exterior surface, a first region including a catalyst and a second region from which the catalyst is at least partially removed. Further, the arcuate exterior surface may be defined by a portion of the first region including the catalyst and a portion of the second region from which the catalyst is at least partially removed. In another embodiment, the polycrystalline diamond layer may include a convex exterior surface for contacting a subterranean formation, wherein at least a portion of a catalyst used for forming the polycrystalline diamond layer is removed from a region of the polycrystalline diamond layer. Subterranean drilling tools (e.g., percussive drill bits) including at least one polycrystalline diamond insert are disclosed.
1. A polycrystalline diamond insert comprising:
a polycrystalline diamond layer affixed to a substrate, the polycrystalline diamond layer comprising:
a first region including a catalyst used for forming the polycrystalline diamond layer, the first region extending partially along a side of the polycrystalline diamond insert;
a second region from which the catalyst is at least partially removed, the second region extending along a top and the side of the polycrystalline diamond insert, the second region having a first thickness at a first location and a second thickness at a second location;
an arcuate exterior surface at least partially defined by the second region.
2. The polycrystalline diamond insert of claim 1 , wherein at least a portion of the arcuate exterior surface is structured for percussively contacting a subterranean formation.
3. The polycrystalline diamond insert of claim 1 , wherein the catalyst used for forming the polycrystalline diamond layer is substantially removed from the second region of the polycrystalline diamond layer.
4. The polycrystalline diamond insert of claim 1 , wherein the arcuate exterior surface is substantially spherical or substantially hemispherical.
5. The polycrystalline diamond insert of claim 1 , wherein the first region has a first thickness at a first location and a second thickness at a second location.
6. A polycrystalline diamond insert comprising:
a polycrystalline diamond layer affixed to a substrate and defining a top surface and at least a portion of a side surface of the polycrystalline diamond insert;
wherein at least a portion of a catalyst used for forming the polycrystalline diamond layer is substantially removed from a region of the polycrystalline diamond layer;
wherein the at least partially leached layer region exhibits a first thickness at a first location and a second thickness at a second location;
wherein the polycrystalline diamond layer includes a convex exterior surface for contacting a subterranean formation.
7. The polycrystalline diamond insert of claim 6 , wherein at least a portion of the convex exterior surface is structured for percussively contacting a subterranean formation.
8. The polycrystalline diamond insert of claim 6 , wherein the at least partially leached region extends partially along the side surface.
9. The polycrystalline diamond insert of claim 6 , wherein the convex exterior surface is substantially spherical or substantially hemispherical.
10. The polycrystalline diamond insert of claim 6 , wherein an unleached portion of the polycrystalline diamond layer that includes the catalyst extends at least partially along the side surface.
11. The polycrystalline diamond insert of claim 6 , wherein an unleached portion of the polycrystalline diamond layer exhibits a first thickness at a first location and a second thickness at a second location.
12. A percussion drill bit for forming a borehole in a subterranean formation, comprising:
a bit body comprising a leading end structured for facilitating formation of a subterranean formation by percussive interaction with the subterranean formation;
at least one polycrystalline diamond insert coupled to the leading end of the bit body, the at least one polycrystalline diamond insert comprising:
a polycrystalline diamond layer affixed to a substrate, the polycrystalline diamond layer comprising:
a first region including a catalyst used for forming the polycrystalline diamond layer, the first region extending partially along at least a portion of a side of the polycrystalline diamond insert;
a second region from which the catalyst is at least partially removed, the second region extending along a top and at least a portion of the side of the polycrystalline diamond insert, the second region having a first thickness at a first location and a second thickness at a second location;
an arcuate exterior surface at least partially defined by the second region.
13. The percussion drill bit of claim 12 , wherein the at least one polycrystalline diamond insert is brazed to the bit body or is press-fit within a recess formed in the bit body.
14. The percussion drill bit of claim 12 , wherein the second region exhibits a first thickness at a first location and a second thickness at a second location.
15. The percussion drill bit of claim 12 , wherein the catalyst used for forming the polycrystalline diamond layer is substantially removed from the second region of the polycrystalline diamond layer.
16. The percussion drill bit of claim 12 , wherein the arcuate exterior surface is substantially spherical or substantially hemispherical.
17. The percussion drill bit of claim 12 , wherein the first region exhibits a first thickness at a first location and a second thickness at a second location.