An improved temperature stable synthetic polycrystalline diamond (PCD) product includes at least one temperature stable PCD integrally and chemically bonded to a matrix carrier support through a carbide forming layer which is of a thickness of at least about 1 micron, the layer on at least one surface of the PCD is in turn bonded to the matrix carrier. A wide variety of shapes, sizes and configurations of such products is achieved through relatively low temperature and relatively low pressure processing. Various products of various geometries are described as well as the details of the processing to achieve chemical bonding of the PCD elements in a variety of support matrix carrier materials to form a unitary structure having a temperature stability up to about 1,200 degrees C.

Low pressure bonding of PCD bodies and method for drill bits and the like

Low pressure bonding of PCD bodies and method

An improved temperature stable synthetic polycrystalline diamond (PCD) product includes at least one temperature stable PCD integrally and chemically bonded to a matrix carrier support through a carbide forming layer which is of a thickness of at least about 1 micron, the layer on at least one surface of the PCD is in turn is bonded to the matrix carrier. A wide variety of shapes, sizes and configurations of such products is achieved through relatively low temperature and relatively low pressure processing. Various products of various geometries are described as well as the details of the processing to achieve chemical bonding of the PCD elements in a variety of support matrix carrier materials to form a unitary structure having a temperature stability up to about 1,200 degrees C.

Method for low pressure bonding of PCD bodies

Multiple metal coated diamond grit for improved retention in a tool matrix comprises a first layer coating of a metal carbide of a strong carbide former, preferably chromium, titanium or zirconium, chemically bonded to the diamond and a second metal coating of an oxidation resistant carbide former, preferably tungsten or tantalum, chemically bonded to the first metal layer. A third metal layer coating of an alloying metal, preferably nickel, can also be added. In accordance with the method of the present invention, the first layer metal can be applied by metal vapor deposition. The second layer metal can be applied by chemical vapor deposition. The third layer of an alloying metal can be applied by electroless or electrolytic plating.

Multiple metal coated superabrasive grit and methods for their manufacture

The invention provides a method of metal coating diamond or cubic boron nitride particles, the metal being capable of forming a chemical bond with the particles, including the steps of providing a mass of metal for the coating in powdered form in contact with the particles, heat treating the metal powder and the particles at a temperature below the melting point of the metal to deposit a layer of metal on the particles, and recovering the particles as discrete, metal coated particles, the heat treatment taking place in a non-oxidizing atmosphere and being chosen to allow chemical bond formation between the particles and the coating.

Metal coating of abrasive particles

A method of producing metal coated diamond particles in which the coatings are strongly bonded to the diamond particles characterised in that a layer of an alloy consisting of a major proportion of a metal such as copper, nickel or iron and a minor proportion of a carbide-forming metal such as titanium, chromium or vanadium is applied to the uncoated particles and then the coated particles are heat treated to a temperature of between 500*C and a temperature just below the melting point of the alloy for a time sufficient to enable a bonding carbide layer to form at the alloy/diamond interface, the steps being carried out in a non-oxidising atmosphere. The invention further provides diamond particles having bonded thereto an alloy comprising a major proportion of nickel and a minor proportion of a carbide-forming metal such as titanium, chromium or vanadium, the bonding being achieved by means of a carbide layer, which is preferably continuous, at the alloy/diamond interface.

Bruce I. Dewar

Papers

Method for metal coating diamonds so as to improve the interfacial bond strength

Metal coating of diamonds