<p>Large diamond crystals are produced in a reaction vessel which contains a tetrahedrally bonded crystalline non-diamond seed material (30) separated from a source (26) of substantially pure carbon by a mass (24) of metallic catalyst/solvent for diamond synthesis. The arrangement is such that a temperature gradient is created between the seed material (30) and the carbon source (26) under the applied conditions of temperature and pressure such that the seed material is located at a point near the minimum value of temperature for the gradient and the carbon source is located at a point near the maximum value of temperature for the temperature gradient. Examples of suitable non-diamond seed material are cubic boron nitride and alpha -silicon carbide.</p>
申请公布号
EP0322217(A1)
申请公布日期
1989.06.28
申请号
EP19880312120
申请日期
1988.12.21
申请人
DE BEERS INDUSTRIAL DIAMOND DIVISION (PROPRIETARY) LIMITED
发明人
DAVIES, GEOFFREY JOHN;BURNS, ROBERT CHARLES;GARDNER, STEPHEN