A method of making a bonded, coherent material and a bonded, coherent material

• Main Authors: TANK, KLAUS, CHAPMAN, RAYMOND ALBERT, DAVIES, GEOFFREY JOHN, ADIA, MOOSA MAHOMED, CAMPBELL, JAMES WILBERT
• Format: Patent
• Language: English
• Published: 11.09.2001
• Edition: 7
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; ALLOYS; APPARATUS THEREFOR; ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; COMPOUNDS THEREOF; CONCRETE; CRYSTAL GROWTH; FERROUS OR NON-FERROUS ALLOYS; INORGANIC CHEMISTRY; LIME, MAGNESIA; METALLURGY; NON-METALLIC ELEMENTS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; REFRACTORIES; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; SLAG; THEIR RELEVANT APPARATUS; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; TREATMENT OF NATURAL STONE; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

A method of making a bonded, coherent material comprising a mass of diamond crystals in a matrix which optionally contains another phase. The method includes the steps of providing a source of diamond crystals, providing a plurality of diamond centres defined by diamond crystals, producing a reaction mass by bringing the source and growth centres into contact with a solvent/catalyst, subjecting the reaction mass to conditions of elevated temperature and pressure suitable for crystal growth in the reaction zone of a high temperature/high pressure apparatus to produce the material, and removing the material from the reaction zone. The method is characterized by providing the necessary supersaturation of carbon in the solvent/catalyst, at least in part and preferably predominantly, by a selection of particle size difference between the source crystal and the growth centres. The mass of diamond crystals in the matrix of the bonded, coherent material of the invention has a high concentration of twinned diamonds.