An abrasive article configured to grind a workpiece having a fracture toughness of at least about 5.5 MPa.Math.m.sup.0.5 may include a body comprising abrasive particles contained within a bond material comprising a metal, wherein the body comprises a ratio of V.sub.AG/V.sub.BM of at least about 1.3, wherein V.sub.AG is a volume percent of abrasive particles within a total volume of the body and V.sub.BM is a volume percent of bond material within the total volume of the body, and wherein the abrasive particles have an average particle size of at least about 1 micron and not greater than about 20 microns.

A vitrified bond grindstone includes abrasive grains and a bonding material for fixing the abrasive grains, the bonding material includes a parent material containing SiO.sub.2 as a main constituent, a sintering assistant oxide, and ZnO, and the content of ZnO is 11 to 15 wt % in weight ratio based on the bonding material. Preferably, the content of the sintering assistant oxide is 20 to 29 wt % in weight ratio based on the bonding material.

A vitrified bond grindstone includes abrasive grains and a bonding material for fixing the abrasive grains, the bonding material includes a parent material containing SiO.sub.2 as a main constituent, a sintering assistant oxide, and ZnO, and the content of ZnO is 11 to 15 wt % in weight ratio based on the bonding material. Preferably, the content of the sintering assistant oxide is 20 to 29 wt % in weight ratio based on the bonding material.

A method of processing a superabrasive element includes providing a superabrasive element including a polycrystalline diamond table that includes a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table. The polycrystalline diamond table includes a superabrasive face and a superabrasive side surface extending around an outer periphery of the superabrasive face. The method also includes leaching the metallic material from at least a volume of the polycrystalline diamond table to produce a leached volume in the polycrystalline diamond table by (1) exposing at least a portion of the polycrystalline diamond table to a processing solution, (2) exposing an electrode to the processing solution, and (3) applying a charge to the electrode such that a voltage is generated between the polycrystalline diamond table and the electrode and the voltage is applied to the processing solution.

A method of processing a superabrasive element includes providing a superabrasive element including a polycrystalline diamond table that includes a metallic material disposed in interstitial spaces defined within the polycrystalline diamond table. The polycrystalline diamond table includes a superabrasive face and a superabrasive side surface extending around an outer periphery of the superabrasive face. The method also includes leaching the metallic material from at least a volume of the polycrystalline diamond table to produce a leached volume in the polycrystalline diamond table by (1) exposing at least a portion of the polycrystalline diamond table to a processing solution, (2) exposing an electrode to the processing solution, and (3) applying a charge to the electrode such that a voltage is generated between the polycrystalline diamond table and the electrode and the voltage is applied to the processing solution.

Polycrystalline compacts include a polycrystalline material comprising a plurality of inter-bonded grains of hard material, and a metallic material disposed in interstitial spaces between the inter-bonded grains of hard material. At least a portion of the metallic material comprises a metal alloy that includes two or more elements. A first element of the two or more elements comprises at least one of cobalt, iron, and nickel. A second element of the two or more elements comprises at least one of dysprosium, yttrium, terbium, gadolinium, germanium, samarium, neodymium, and praseodymium. The metal alloys may comprise eutectic or near-eutectic compositions, and may have relatively low melting points. Cutting elements and earth-boring tools include such polycrystalline compacts. Methods include the formation of such polycrystalline compacts, cutting elements, and earth-boring tools.

Polycrystalline compacts include a polycrystalline material comprising a plurality of inter-bonded grains of hard material, and a metallic material disposed in interstitial spaces between the inter-bonded grains of hard material. At least a portion of the metallic material comprises a metal alloy that includes two or more elements. A first element of the two or more elements comprises at least one of cobalt, iron, and nickel. A second element of the two or more elements comprises at least one of dysprosium, yttrium, terbium, gadolinium, germanium, samarium, neodymium, and praseodymium. The metal alloys may comprise eutectic or near-eutectic compositions, and may have relatively low melting points. Cutting elements and earth-boring tools include such polycrystalline compacts. Methods include the formation of such polycrystalline compacts, cutting elements, and earth-boring tools.

A metal bond grindstone grinds a hard and brittle material. The metal bond grindstone includes: a metal bond; abrasive grains bound by the metal bond; and pores having a pore size of 50-200 μm, such that a porosity in an entirety of the metal bond grindstone is 50-65 vol %. A number of the abrasive grains on a grinding surface excluding the pores may be 700-6500 grains/cm.sup.2. The abrasive grains may be diamond abrasive grains, and a grain size of the abrasive grains may be 4-20 μm in median size. The metal bond grindstone may have a grindstone strength of 40-95 MPa.

A metal bond grindstone grinds a hard and brittle material. The metal bond grindstone includes: a metal bond; abrasive grains bound by the metal bond; and pores having a pore size of 50-200 μm, such that a porosity in an entirety of the metal bond grindstone is 50-65 vol %. A number of the abrasive grains on a grinding surface excluding the pores may be 700-6500 grains/cm.sup.2. The abrasive grains may be diamond abrasive grains, and a grain size of the abrasive grains may be 4-20 μm in median size. The metal bond grindstone may have a grindstone strength of 40-95 MPa.

Polycrystalline diamond cutting elements with modified catalyst depleted portions and methods of making the same are disclosed herein. A method may include removing inter-bonded diamond grains along an outer surface of a polycrystalline diamond compact to form a frustoconical surface, introducing the polycrystalline diamond compact to a leaching process in which catalyst material that is positioned within interstitial regions between the inter-bonded diamond grains is removed from the polycrystalline diamond compact, and removing inter-bonded diamond grains along the outer surface of the polycrystalline diamond compact to form a polycrystalline diamond cutting element having a peripheral surface.