Polycrystalline diamond compact including a substrate having a raised interfacial surface bonded to a polycrystalline diamond table, and applications therefor

A polycrystalline diamond compact, comprising:

• a substrate including an interfacial surface having a raised region and a peripheral region extending about the raised region, the raised region having an upper surface at a first height above the peripheral region, the first height being greater than 0 μm and less than about 450 μm, wherein a surface area of the raised region comprises at least 60 percent of a total surface area of the interfacial surface of the substrate;
• and
• a polycrystalline diamond table bonded to the interfacial surface of the substrate and integrally formed with the substrate, the polycrystalline diamond table including an upper surface at a second height of less than 950 μm above the peripheral region of the substrate and at least one peripheral surface, the polycrystalline diamond table including a plurality of bonded diamond grains defining a plurality of interstitial regions, the polycrystalline diamond table including:
• an unleached first region adjacent to the substrate in which at least a portion of the plurality of interstitial regions of the first region includes a metallic constituent disposed in the unleached first region;
• and
• a leached second region from which the metallic constituent is depleted that extends about 100 μm to about 500 μm inwardly from the upper surface, at least a portion of the second region as measured from the upper surface of the polycrystalline diamond table extending past the upper surface of the raised region.

A rotary drill bit, comprising:

• a bit body configured to engage a subterranean formation;
• and
• a plurality of polycrystalline diamond cutting elements affixed to the bit body, at least one of the polycrystalline diamond cutting elements including:
• a substrate including an interfacial surface having a raised region and a peripheral region extending about the raised region, the raised region having an upper surface at a height above the peripheral region, the height being greater than 0 μm and less than about 450 μm;
• and
• a polycrystalline diamond table bonded to the interfacial surface of the substrate and integrally formed with the substrate, the polycrystalline diamond table including an upper surface and at least one peripheral surface, the polycrystalline diamond table including a plurality of bonded diamond grains defining a plurality of interstitial regions, the polycrystalline diamond table including:
• an unleached first region adjacent to the substrate in which at least a portion of the plurality of interstitial regions of the first region includes a metallic constituent disposed in the unleached first region;
• and
• a leached second region from which the metallic constituent is depleted that extends inwardly from the upper surface, at least a portion of the leach region as measured from the upper surface of the polycrystalline diamond table extending past the upper surface of the raised region.