Polycrystalline diamond compacts including a cemented carbide substrate

A rotary drill bit, comprising:

• a bit body configured to facilitate drilling a subterranean formation, the bit body including blades;
• and
• a plurality of cutting elements mounted to the blades, at least one of the plurality of cutting elements including:
• a cemented carbide substrate including a cobalt-containing cementing constituent cementing a plurality of tungsten carbide grains together, the plurality of tungsten carbide grains exhibiting an average grain size of about 0.8 μm to about 1.5 μm, the cemented carbide substrate including an interfacial surface and a depletion zone that extends inwardly from an interfacial surface thereof to a depth of about 30 μm to about 50 μm, the depletion zone exhibiting a Palmquist fracture toughness of about 6 MPa·m0.5 to about 9 MPa·0.5, wherein the cemented carbide substrate excludes chromium;
• and
• a polycrystalline diamond table bonded to the interfacial surface of the cemented carbide substrate, the polycrystalline diamond table including a plurality of diamond grains bonded together and defining a plurality of interstitial regions, the plurality of the diamond grains exhibiting an average grain size of about 40 μm or less, at least a portion of the polycrystalline diamond able including a metallic constituent disposed in at least a portion of the plurality of interstitial regions, the metallic constituent of the at least a portion of the polycrystalline diamond table is present in an amount of about 7.5 weight % or less, the at least a portion of the polycrystalline diamond table exhibiting a coercivity of about 130 Oe to about 250 Oe and a specific magnetic saturation of about 5 G·cm3/g to about 15 G·cm3/g.

A drill bit, comprising:

• a bit body configured to facilitate drilling a subterranean formation, the bit body including blades;
• and
• a plurality of cutting elements mounted to the blades, at least one of the plurality of cutting elements including:
• a single cemented carbide substrate including a cobalt-containing cementing constituent cementing a plurality of tungsten carbide grains together, the plurality of tungsten carbide grains exhibiting an average grain size of about 1 μm to about 1.5 μm, the single cemented carbide substrate including an interfacial surface and a depletion zone that extends inwardly from an interfacial surface thereof to a depth of about 30 μm to 50 μm, the depletion zone exhibiting a Palmquist fracture toughness of about 6 MPa·m0.5 to about 9 MPa·m0.5, wherein the single cemented carbide substrate:
• excludes chromium;
• and
• exhibits a transverse rupture strength of about 460 ksi to about 550 ksi, a hardness of about 89.5 HRa to about 92 HRa, a coercivity of about 130 to about 150 Oe, a magnetic saturation of about 10 G·cm3/g to about 20 G·cm3/g, and corrosion pits having an average width of about 0.5 μm to about 2.5 μm after immersing the single cemented carbide substrate in 10% hydrochloric acid for about 24 hours;
• and
• a polycrystalline diamond table bonded to the interfacial surface of the single cemented carbide substrate, the polycrystalline diamond table including a plurality of diamond grains bonded together and defining a plurality of interstitial regions, the plurality of the diamond grains exhibiting an average grain size of about 40 μm or less, at least a portion of the polycrystalline diamond able including a metallic constituent disposed in at least a portion of the plurality of interstitial regions, the metallic constituent of the at least a portion of the polycrystalline diamond table is present in an amount of about 7.5 weight % or less, the at least a portion of the polycrystalline diamond table exhibiting a coercivity of about 115 Oersteds (“Oe”) to about 250 Oe and a specific magnetic saturation of about 15 Gauss·cm3/grams or less.