Abstract: The present invention relates to a method of producing a composite rod from a braze material and a sheet of material comprising cermet. The method comprises scoring a surface of the sheet to produce at least one line of localised stress and subsequently causing the sheet to break along the line of localised stress, thereby to produce a plurality of cermet chunks. The cermet chunks can be combined with the braze material to produce the composite rod. In a particular embodiment, the sheet of material may be a used cermet cutting tip.

Abstract: A hard faced surface comprises a metal substrate. Inserts are attached to the substrate as a covering layer on the substrate. Each insert comprises a thermally stable polycrystalline diamond (TSP) body (or polycrystalline diamond or cubic boron nitride) having a plan section, a contact surface and a flat top surface. A boundary coating on the ultra-hard body renders the body wettable by first braze material. A tungsten carbide cap is brazed with said first braze material to at least the top surface of the TSP block. The inserts are brazed to the substrate in a closely packed side-by-side formation with a second braze material that penetrates the gaps between the inserts and between the contact surface of the bodies and the metal substrate. The tungsten carbide caps of the inserts provide a gauge for the hard faced surface, which caps are ground in a finishing step exposing the caps and providing the hard faced surface with a desired dimension including an amount of the thickness of the caps.

Abstract: A hard faced surface comprises a metal substrate. Inserts are attached to the substrate as a covering layer on the substrate. Each insert comprises a thermally stable polycrystalline diamond (TSP) body (or polycrystalline diamond or cubic boron nitride) having a plan section, a contact surface and a flat top surface. A boundary coating on the ultra-hard body renders the body wettable by first braze material. A tungsten carbide cap is brazed with said first braze material to at least the top surface of the TSP block. The inserts are brazed to the substrate in a closely packed side-by-side formation with a second braze material that penetrates the gaps between the inserts and between the contact surface of the bodies and the metal substrate. The tungsten carbide caps of the inserts provide a gauge for the hard faced surface, which caps are ground in a finishing step exposing the caps and providing the hard faced surface with a desired dimension including an amount of the thickness of the caps.

Abstract: A method of construction of a tungsten carbide/TSP insert for hard facing a wear surface comprises the steps of forming a tungsten carbide body (12) in a mould. After the moulding step, a channel section slot (24) or pocket (24?) is created in the body before it has hardened substantially. The body is then heat-treated to harden it. A TSP body (32) is fitted in the slot/pocket (24/24?) so that it is a close sliding fit between the sides (18) of the slot, and is of the same depth as the slot. The TSP is (preferably) brazed into the slot. The insert has pips (30) on its edges (18) to facilitate welding to a substrate prior to a final brazing step.

Abstract: A method of facing a substrate comprises the steps of first welding a body of a hard facing material to the substrate and then filling a space around the body with a molten metal. The method can be used in the hard facing of metal components with, for example, hard facing materials such as tungsten carbide. The substrate can comprise a metal surface, which can, for example, be the surface of any suitable component, tool, or implement subject to wear in use. The method is particularly suitable for hard facing the wear surfaces of components for use in drill strings in down-hole drilling technology, for example, drill stabilizers.