Abstract: A brazing rod for use in depositing an abrasive metal coating on a metal substrate. The brazing rod comprises particulate abrasive material selected from the group consisting of diamond particles and mixtures of diamond particles and carbide particles and a matrix comprising a braze alloy which is sufficiently sintered together to bind the particulate abrasive material into a rigid rod. The braze alloy contains one component selected from the group consisting of nickel, nickel alloy, silver, silver alloy, gold, gold alloy, copper, copper alloy and mixtures thereof, and a second component selected from the group consisting of iron, iron alloy, cobalt, cobalt alloy, tin, tin alloy, boron, silicon, chromium, chromium alloy and mixtures thereof. The diamond particles are coated with a material selected from the group consisting of tungsten, molybdenum, chromium, nickel, iron, cobalt, palladium, tungsten carbide, molybdenum carbide, chromium carbide and iron carbide.

Abstract: A brazing rod is disclosed for use in depositing an abrasive metal coating on a metal substrate. The brazing rod comprises an elongate metal tube made of a metal selected from the group consisting of copper, bronze, brass, nickel, nickel alloys, iron, cobalt and steel. A brazing mixture is contained in the metal tube and comprises a particulate abrasive material selected from the group consisting of diamond particles and mixtures of diamond particles and carbide particles. The brazing mixture further contains powdered braze alloy in which one component of the braze alloy is a member selected from the group consisting of nickel, nickel alloy, silver, silver alloy, gold, gold alloy, copper, copper alloy and mixtures thereof, and in which a second component of said braze alloy is selected from the group consisting of iron, iron alloy, cobalt, cobalt alloy, tin, tin alloy, boron, silicon, chromium, chromium alloy and mixtures thereof.

Abstract: A rotary drill bit for boring earth formations is provided which includes a main body portion of a hard metal matrix material and at least one protrusion or shoulder formed of the same matrix material. On the protrusion is mounted a cutting element. Means for reinforcing the protrusion are provided and extend between the main body portion of the bit and the protrusion. The reinforcements add impact strength to the bit and increase the resistance of the bit to cracking in areas supporting the cutting element.

Abstract: To prevent thermal stress from damaging a PCD or diamond, multilayer metal coatings for bonding polycrystalline diamond compacts and diamond crystals to a matrix comprise a first metal layer of a refractory metal, such as tungsten, a compliant metal layer of copper, and an outer metal layer of a refractory metal such as tungsten. Metallic bonding layers of a metal, such as nickel, are placed between the tungsten and copper layers for improved bonding. The method of manufacturing multilayer metal coatings comprises applying the inner metal layer by chemical vapor deposition, applying the first bonding layer metal by electrolytic deposition, applying the compliant layer metal by electrolytic deposition, applying the second bonding layer by electrolytic deposition and applying the outer layer by chemical vapor deposition. A superabrasive tool element comprises a coated diamond product bonded either to a matrix comprising tungsten carbide or iron powder or to a cemented tungsten carbide support.

Abstract: A novel infiltration alloy comprises about 5 to 65% by weight of manganese, up to about 35% by weight of zinc, and the balance copper. Preferably, the infiltration alloy comprises 20% by weight of manganese, 20% by weight of zinc, and the balance copper. The infiltration alloy is useful in the manufacture of matrix bodies such as matrix drill bit bodies. A method for the manufacture of a matrix body comprises forming a hollow mold for molding at least a portion of the matrix body, positioning diamond cutting elements in the mold, packing at least a part of the mold with a powder matrix material, infiltrating the matrix material with the novel infiltration alloy in a furnace to form a mass, and allowing the mass to solidify into an integral matrix body. Because the novel infiltration alloy permits infiltration to be carried out at temperatures below about 1050.degree. C., many diamond cutting elements which begin to deteriorate at temperatures above 1000.degree. C.