Thermally-stable polycrystalline diamond element and compact, and applications therefor such as drill bits

A polycrystalline diamond compact, comprising:

• a substrate;
• a polycrystalline diamond table bonded to the substrate, the polycrystalline diamond table including bonded diamond grains defining a plurality of interstitial regions, the polycrystalline diamond table including a first volume remote from the substrate having an infiltrant disposed interstitially between the bonded diamond grains thereof and a second volume adjacent to the substrate having metal-solvent catalyst disposed interstitially between the bonded diamond grains thereof;
• and
• wherein the infiltrant comprises at least one member selected from the group consisting of a glass, a glass-ceramic, silicone, a thermal decomposition reaction product of silicone, and a ceramic having a negative coefficient of thermal expansion.

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 polycrystalline diamond body including bonded diamond grains defining a plurality of interstitial regions, the polycrystalline diamond body including a first volume having a first portion of the interstitial regions and a second volume having a second portion of the interstitial regions, the first volume including an infiltrant disposed in the first portion of the interstitial regions thereof and the second volume being substantially free of the infiltrant;
• and
• wherein the infiltrant comprises at least one member selected from the group consisting of a glass, a glass-ceramic, silicone, a thermal decomposition reaction product of silicone, and a ceramic having a negative coefficient of thermal expansion.