An abrasive article includes a polycrystalline material comprising abrasive grains and a filler material selected from the group of materials consisting of tungstate, molybdate, vanadate, and a combination thereof. Earth-boring tools comprise a bit body and a cutting element carried by the bit body. The cutting element comprises a polycrystalline material comprising abrasive grains, a catalyst material, and a filler material selected from the group of materials consisting of tungstate, molybdate, vanadate, and a combination thereof

An abrasive article includes a body having abrasive grains contained within a bond material comprising a metal or metal alloy, wherein the body comprises a ratio of V.sub.AG/V.sub.BM of at least about 1.3, wherein V.sub.AG is the volume percent of abrasive grains within the total volume of the body and V.sub.BM is the volume percent of bond material within the total volume of the body.

Embodiments of the invention relate to methods of fabricating a polycrystalline diamond compacts and applications for such polycrystalline diamond compacts. In an embodiment, a method of fabricating a polycrystalline diamond body includes mechanically milling non-diamond carbon and a sintering aid material for a time and aggressiveness sufficient to form a plurality of carbon-saturated sintering aid particles and sintering a plurality of diamond particles in the presence of the plurality of carbon-saturated sintering aid particles to form the polycrystalline diamond body.

Embodiments of the invention relate to methods of fabricating a polycrystalline diamond compacts and applications for such polycrystalline diamond compacts. In an embodiment, a method of fabricating a polycrystalline diamond body includes mechanically milling non-diamond carbon and a sintering aid material for a time and aggressiveness sufficient to form a plurality of carbon-saturated sintering aid particles and sintering a plurality of diamond particles in the presence of the plurality of carbon-saturated sintering aid particles to form the polycrystalline diamond body.

A method of making a polycrystalline diamond compact includes forming multiple layers of premixed diamond particles and carbonate material, where the carbonate material includes an alkaline earth metal carbonate, and where each layer has a weight percent ratio of diamond to carbonate that is different from adjacent layers. The layers are subjected to high pressure high temperature conditions to form polycrystalline diamond.

A method of making a polycrystalline diamond compact includes forming multiple layers of premixed diamond particles and carbonate material, where the carbonate material includes an alkaline earth metal carbonate, and where each layer has a weight percent ratio of diamond to carbonate that is different from adjacent layers. The layers are subjected to high pressure high temperature conditions to form polycrystalline diamond.

Methods of forming a polycrystalline compact using at least one metal salt as a sintering aid. Such methods may include forming a mixture of the at least one metal salt and a plurality of grains of hard material and sintering the mixture to form a hard polycrystalline material. During sintering, the metal salt may melt or react with another compound to form a liquid that acts as a lubricant to promote rearrangement and packing of the grains of hard material. The metal salt may, thus, enable formation of hard polycrystalline material having increased density, abrasion resistance, or strength. The metal salt may also act as a getter to remove impurities (e.g., catalyst material) during sintering. The methods may also be employed to form cutting elements and earth-boring tools.

A polycrystalline diamond body, and a method for making a carbonate polycrystalline diamond body includes combining a first quantity of diamond particles with a first quantity of magnesium carbonate to form a first layer in an enclosure, the first layer having a working surface, and placing a second quantity of magnesium carbonate in the enclosure forming a second layer, the first layer and the second layer forming an assembly. A quantity of at least one of silicon or aluminum is mixed in with or placed adjacent to at least one of the first layer or the second layer. The assembly, including the at least one of silicon or aluminum, is sintered at high pressure and high temperature, causing the at least one of silicon or aluminum to infiltrate at least one layer of the assembly, forming a polycrystalline diamond body.

A polycrystalline diamond body, and a method for making a carbonate polycrystalline diamond body includes combining a first quantity of diamond particles with a first quantity of magnesium carbonate to form a first layer in an enclosure, the first layer having a working surface, and placing a second quantity of magnesium carbonate in the enclosure forming a second layer, the first layer and the second layer forming an assembly. A quantity of at least one of silicon or aluminum is mixed in with or placed adjacent to at least one of the first layer or the second layer. The assembly, including the at least one of silicon or aluminum, is sintered at high pressure and high temperature, causing the at least one of silicon or aluminum to infiltrate at least one layer of the assembly, forming a polycrystalline diamond body.

According to one embodiment, a composite product includes: a matrix material including hexagonal boron nitride and one or more borate binders; and a plurality of cubic boron nitride particles dispersed in the matrix material. According to another embodiment, a composite product includes: a matrix material including hexagonal boron nitride and amorphous boron nitride; and a plurality of cubic boron nitride particles dispersed in the matrix material.