Abstract: A drill bit that includes a bit body formed from a matrix powder and at least one cutting element for engaging a formation, wherein the matrix powder included (a) stoichiometric tungsten carbide particles, (b) cemented tungsten carbide particles, and (c) cast tungsten carbide particles, and wherein after formation with the matrix powder, the bit has an erosion rate of less than 0.001 in/hr, a toughness of greater than 20 ksi(in0.5), and a transverse rupture strength of greater than 140 ksi is disclosed.

Abstract: Cutting elements offering increased toughness and thermal fatigue resistance can be formed of a wear resistant material having coarse grains disposed in a binder matrix with a binder content of at least about 18% by weight. The coarse grains include grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride. The binder content and coarse grain size may be selected to provide a Rockwell A hardness of at least about 75 Ra or a wear number of at least about 1.5.

Abstract: Fracture and wear resistant cutting elements are provided. Examples include a cutting element formed of a wear resistant material having a binder composition and a coarse grain size such that the portion of the cutting element formed of the wear resistant material has a fracture toughness of at least about 18 ksi(in)0.5 and a wear number of at least about 1.8. In a particular example, the wear resistant material has a fracture toughness of at least about 20 ksi(in)0.5. A down hole cutting tool incorporating such cutting elements is also provided.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: A drill bit that includes a bit body formed from a matrix powder and at least one cutting element for engaging a formation, wherein the matrix powder included (a) stoichiometric tungsten carbide particles, (b) cemented tungsten carbide particles, and (c) cast tungsten carbide particles, and wherein after formation with the matrix powder, the bit has an erosion rate of less than 0.001 in/hr, a toughness of greater than 20 ksi(in0.5), and a transverse rupture strength of greater than 140 ksi is disclosed.

Abstract: A method for manufacturing drill bit inserts in which the inserts are finished in a centrifugal disc finishing machine. The centrifugal disc finishing machine comprises a configured surface rotating relative to a stationary receptacle, and the inserts may be finished with a mass of materials comprising at least one of a group of media, parts, detergent, and solution. Also, a method of increasing drill bit insert performance comprising accelerating a plurality of inserts in a high-energy finishing machine, wherein the acceleration results in a generally toroidal interaction between the inserts and at least one of the group comprising media, parts, detergent, and solution.

Abstract: A cutting tool that includes at least one tungsten carbide cutting element disposed on a support, wherein at least one tungsten carbide cutting element has at least one localized region having a material property different from the remaining region, wherein the at least one localized region having a different material property is prepared by a method including determining at least one localized region needing a variation in a material property different from the remaining region; coating a portion of a surface of the at least one tungsten carbide cutting element with a refractory material such that a surface corresponding to the localized region is left uncoated; and treating the coated cutting element with a selected agent to diffuse the selected agent into the localized region is disclosed.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: A composite material includes a double cemented carbide and a coarse grain dopant, wherein the coarse grain is added in an amount sufficient to improve wear resistance of virgin double cemented carbide. The double cemented carbide may selected from the group of carbides consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain dopant may also be at least one carbide selected from the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain carbide may be between about 5% to about 90% by weight of the total carbide in the composite. Preferably, the coarse grain carbide is about 10% to about 50% by weight of the total carbide in the composite.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: Cutting elements having coarse grain substrates and ultra hard material layers are provided. The substrates are formed from coarse grain size particles of tungsten carbide. A method of forming such cutting elements and a drag bit incorporating such cutting elements are also provided.

Abstract: A hardfacing composition for a drill bit, including a carbide phase comprising from about 50% to about 75% by weight of the hardfacing composition of a combination of 16 to 40 mesh cemented tungsten carbide and 80 to 200 mesh super dense tungsten carbide cobalt particles, wherein about 5% to about 50% by weight of the carbide phase comprises the super dense tungsten carbide cobalt particles, and a binder alloy including about 25% to about 50% by weight of the hardfacing composition.

Abstract: The present invention relates to a roller cone drill bit that includes a bit body adapted to be rotated about a longitudinal axis, where the bit body has at least one leg depending therefrom, wherein the leg comprises a treated portion that provides a residual compressive stress, and a roller cone rotatably mounted on a journal. The treated portion treatment may comprise one selected from shot peening, laser-shock peening, and hammer peening. Further, the present invention relates to a method of manufacturing a roller cone drill bit that includes inducing a compressive stress, through plastic deformation, in at least a portion of at least one leg depending from a bit body. The inducing a compressive stress may comprise one selected from shot peening, laser-shock peening, and hammer peening.

Abstract: The present invention relates to hepatitis A vaccine, especially to a lyophilized attenuated hepatitis A vaccine which can be stored at ambient temperature for extended periods of time, and to a method for producing the same. The present invention further relates to a stabilizer for lyophilized live vaccine and its use in improving thermostability of lyophilized live vaccine during lyophilization processing and storage period after lyophilization.

Abstract: A composite material includes a double cemented carbide and a coarse grain dopant, wherein the coarse grain is added in an amount sufficient to improve wear resistance of virgin double cemented carbide. The double cemented carbide may selected from the group of carbides consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain dopant may also be at least one carbide selected from the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain carbide may be between about 5% to about 90% by weight of the total carbide in the composite. Preferably, the coarse grain carbide is about 10% to about 50% by weight of the total carbide in the composite.

Abstract: In one embodiment, a hardfacing composition for a drill bit, including a carbide phase including from about 50% to about 80% by weight of the hardfacing composition of a combination of 80 to 200 mesh macro-crystalline tungsten carbide and 80 to 200 mesh crushed cast carbide, the crushed cast carbide being about 5% to 50% of the total weight of the carbide phase, and a binder alloy comprising about 20% to about 50% by weight of the hardfacing composition is disclosed. A hardfacing composition for a drill bit, including a carbide phase composed of sintered tungsten carbide having a particle size from about 80 to 200 mesh that is about 50% to about 80% by weight of the hardfacing composition, and a binder alloy forming about 20% to about 50% by weight of the hardfacing composition.

Abstract: Fracture and wear resistant cutting elements are provided. Examples include a cutting element formed of a wear resistant material having a binder composition and a coarse grain size such that the portion of the cutting element formed of the wear resistant material has a fracture toughness of at least about 18 ksi(in)0.5 and a wear number of at least about 1.8. In a particular example, the wear resistant material has a fracture toughness of at least about 20 ksi(in)0.5. A down hole cutting tool incorporating such cutting elements is also provided.

Abstract: Cutting elements having coarse grain substrates and ultra hard material layers are provided. The substrates are formed from coarse grain size particles of tungsten carbide. A method of forming such cutting elements and a drag bit incorporating such cutting elements are also provided.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: A hardfacing composition for a drill bit is disclosed which includes a carbide phase made from about 80% to less than 100% by weight of a combination of sintered carbide pellets and crushed cast carbide and from more than 0% to about 20% by weight of carburized tungsten carbide. The composition includes a binder alloy. A roller cone drill bit includes a bit body and at least one roller cone rotatably mounted to the bit body. The at least one roller cone includes at least one cutting element. The cutting element has on its exterior surface a hardfacing. The hardfacing on the cutting element was formed with a hardfacing composition that includes a binder alloy and a carbide phase, which includes from about 80% to less than 100% by weight of a combination of sintered carbide pellets and crushed cast carbide, and from more than 0% to about 20% by weight of carburized tungsten carbide.