Abstract:
A synthetic diamond or cubic boron nitride particle is characterized by containing two or more stable isotopes of an element present in a ratio which is different to the ratio in which the isotopes exist in nature. The diamond or cubic boron nitride particle thus has a fingerprint. A preferred example of the element is nitrogen.
Abstract:
Single-crystal diamond consisting of isotopically pure carbon-12 or carbon-13 has been found to have a thermal conductivity higher than that of any substance previously known, typically at least 40% higher than that of naturally occurring IIA diamond. It may be prepared by a method comprising an initial step of low pressure chemical vapor deposition employing an isotopically pure hydrocarbon in combination with hydrogen, followed by comminution of the diamond thus obtained and conversion thereof to single-crystal diamond under high pressure conditions.
Abstract:
A method and apparatus for selectively treating the surface of a substrate with a material. The method comprises supporting a workpiece at a work station and providing a source of fluent material for treating a preselected portion of a surface of the workpiece. A stream of the fluent material is directed toward the surface of the workpiece while effecting controllable relative movement between the stream of fluent material and the workpiece to impinge a select amount of the fluent material along a preselected path on the preselected portion of the surface of the workpiece. The fluent material is bonded with the preselected portion of the surface of the workpiece to produce a predetermined physical change on the preselected portion. The apparatus of the invention includes a mechanism to effect the specific steps of the novel method.
Abstract:
A fused compact of polycrystalline diamond is formed by dynamically shocking either fine diamond crystals or a mixture of fine diamond crystals and graphite.
Abstract:
An apparatus and method for reacting on material by means of intense radiation employed to change the physical and, in certain instances, the chemical characteristics of such material. In one form, an intense radiation beam is directed into a cavity of a die or support for a small quantity of material to be reacted on and the intense heat of the beam as well as the shock wave generated in the material in the die cavity by the rapid heat of the beam react on such material to change its physical characteristics. In another form, two or more intense radiation beams, such as generated by one or more lasers or electron guns as intense pulses of radiation, are directed against a particle or pellet of material directed along a predetermined path into a reaction chamber, intensely heat and transmit shock wave energy thereto from opposite directions which shock waves collapse against the material transforming it into another form. In still another form of the invention, pellets or small containers of material to be reacted on are supported by filaments, rods or other structures disposed in a reaction chamber and are reacted on by one or more intense radiation beams. In yet another form, one or more intense pulses of radiation are directed against a solid member compressing a quantity of material in a die and generate one or more shock waves in such solid member which are transmitted therethrough to the compressed material. The pellet or particles may comprise carbon which is converted to diamond by the intense heat and force of the shock wave or shock waves or other material including such other material mixed with carbon.
Abstract:
An apparatus and method are provided for making diamonds. In one form, a plurality of shock waves are generated and are directed or focused against carbon particles retained in a cavity of a die such that the heat and pressure of the shock waves will heat and compress the particles of carbon to form one or more diamonds thereof. In another form, diamonds or particles of diamond dust are disposed in a cavity containing carbon particles and serve as substrates or nuclei on which carbon is converted to diamond forming larger diamonds thereof. Each of the diamonds disposed in the mold or die cavity is completely surrounded by carbon. A magnetic jack hammer of the type disclosed in U.S. Pat. No. 3,632,242 having a focusing horn attached thereto is employed to generate and transmit the trains of intermittent shock waves to the diamonds and carbon disposed in the mold. In another form, intense heat and pressure are generated by one or more laser beams which are directed at carbon particles per se or against diamond particles which are packed with carbon particles in a mold so as to form diamonds and/or increase the sizes of the diamonds disposed in the mold cavity with the carbon particles.
Abstract:
Reaction vessel construction is described for suppressing spontaneous diamond nucleation and simultaneously reducing the flaw content in the main body of diamond grown from diamond seed material by the process broadly disclosed in U.S. Pat. No. 3,297,407 to Wentorf, Jr.In the reaction vessel construction the body of catalyst-solvent metal is formed with at least one small tip projecting from the underside thereof. A single diamond seed is placed in contact with this (or each) tip. The underside of the plug of catalyst-solvent metal is in contact with a nucleation-suppressing disc, or layer, of a material different from the catalyst-solvent and selected from a specific group of materials. In each case the tip of catalyst-solvent metal projects through a hole in the disc or layer to make contact with the diamond seed material.
Abstract:
A process for synthesizing larger size diamonds wherein a raw material carbon substance and a solvent-catalyst metal initially isolated from the carbon substance by a metal having no affinity to carbon are subjected to high pressure-high temperature conditions within a diamond-stable region calculated and defined by a specific combination of the carbon substance and solvent-catalyst metal to temporarily restrict nucleation at the reaction earlier stage to control the number of diamond crystal nucleuses.
Abstract:
To synthesize diamond a carbonaceous material in the presence of metals, such as zinc, magnesium, lead, cadmium, bismuth, tin, indium, antimony, thallium, aluminium, mercury and compounds thereof is subjected to a pressure of at least 60 kbar at a temperature of at least 1700*C within the range of diamond stability.
Abstract:
DIAMOND IS SYNTHESIZED BY SUBJECTING A MIXTURE OF GRAPHITE AND A METAL CATALYST TO A TEMPERATURE OF AT LEAST 1150*C. AND A PRESSURE OF AT LEAST 40 KBARS, THROUGHOUT THE ENTIRE VOLUME OF THE CATALYST THERE BEING DISPERSED GRAPHITE CRYSTALLITES. THE PROCESS ENABLES ONE TO PREPARE A LARGE NUMBER OF SEPARATE, SMALL, WELL DEFINED DIAMOND MONOCRYSTALS IN A RELATIVELY SHORT TIME. THE DIAMOND PRODUCT HAS HIGH ABRASION PROPERTIES.