Claims
- 1. A cutting element comprising:
- a substrate having an interface surface, the interface surface comprising a plurality of circular irregularities arranged to form concentric annular rows; and
- a hard material cutting layer having a first surface bonded to the substrate interface surface.
- 2. A cutting element as recited in claim 1 wherein the interface surface is tiered.
- 3. A cutting element as recited in claim 2 wherein the tiered interface surface comprises a plurality of conical sections of decreasing diameter situated concentrically one on top of the other and arranged in decreasing diameter order in a direction away from the base.
- 4. A cutting element as recited in claim 3 wherein each conical section comprises a larger diameter circumference opposite a smaller diameter circumference, wherein the smaller diameter circumference of each section is located further from the base than the larger diameter circumference of that section.
- 5. A cutting element as recited in claim 1 wherein the irregularities are concave dimples.
- 6. A cutting element as recited in claim 5 wherein at least two dimples have different depths.
- 7. A cutting element as recited in claim 1 wherein the irregularities are cylindrical depressions having a concave bottom.
- 8. A cutting element comprising:
- a substrate having a base and a tiered interface surface opposite the base, the tiered interface surface forming a series of steps each step having a planar surface stepping toward the base in a radially outward direction, wherein each step has a depth relative to an adjacent step, wherein the depth of each consecutive step in a radially outward direction is not less than the depth of the radially inward adjacent step;
- a plurality of irregularities formed on the tiered interface surface and surrounded at least in part by the planar surface of at least one of said steps; and
- a hard material cutting layer having a first surface bonded to the substrate tiered interface surface.
- 9. A cutting element as recited in claim 8 wherein the irregularities are dimples.
- 10. A cutting element as recited in claim 8 wherein the tiered interface surface comprises a plurality of conical sections of decreasing diameter situated concentrically one on top of the other and arranged in decreasing diameter order in a direction away from the base.
- 11. A cutting element as recited in claim 10 wherein each conical section comprises a larger diameter circumference opposite a smaller diameter circumference, wherein the smaller diameter circumference of each section is located further from the base than the larger diameter circumference of that section.
- 12. A cutting element comprising:
- a substrate having a base and a tiered interface surface opposite the base, the tiered interface surface comprising a plurality of conical sections of decreasing diameter situated concentrically one on top of the other and arranged in decreasing diameter order in a direction away from the base;
- a plurality of irregularities formed on the tiered interface surface; and
- a hard material cutting layer having a first surface bonded to the substrate tiered interface surface.
- 13. A cutting element as recited in claim 12 wherein each conical section comprises a larger diameter circumference opposite a smaller diameter circumference, wherein the smaller diameter circumference of each section is located further from the base than the larger diameter circumference of that section.
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority pursuant to 35 U.S.C. .sctn. 119(e) and 37 CFR .sctn. 1.78(a)(4), to provisional Application No. 60/033,239, filed on Dec. 6, 1996.
US Referenced Citations (49)