POLYCRYSTALLINE COMPACTS HAVING MATERIAL DISPOSED IN INTERSTITIAL SPACES THEREIN, CUTTING ELEMENTS AND EARTH-BORING TOOLS INCLUDING SUCH COMPACTS, AND METHODS OF FORMING SUCH COMPACTS

摘要

Polycrystalline compacts include smaller and larger hard grains that are interbonded to form a polycrystalline hard material. The larger grains may be at least about 150 times larger than the smaller grains. An interstitial material comprising one or more of a boride, a carbide, a nitride, a metal carbonate, a metal bicarbonate, and a non-catalytic metal may be disposed between the grains. The compacts may be used as cutting elements for earth-boring tools such as drill bits, and may be disposed on a substrate. A particulate mixture includes a first plurality of grains of hard material having a first average grain size of about five hundred nanometers (500 nm) or less and having a coating formed over the grains of hard material. The coating comprises at least one of a boride, a carbide, a nitride, a metal carbonate, a metal bicarbonate, and a non-catalytic metal.