Abstract:
Methods for forming cutting elements comprising polycrystalline materials, methods for forming polycrystalline compacts for cutting elements of a drilling tool, methods for forming polycrystalline diamond compacts, and resulting polycrystalline compacts and cutting elements are disclosed. Grains of a hard material are introduced to a press and subjected to a high-pressure, high-temperature (HPHT) process to sinter the grains. The system conditions (i.e., temperature and pressure) are then adjusted past a phase or state change point, after which, at least one of the system conditions is held during an anneal stage before the system conditions are adjusted to final levels. The resulting compacts and cutting elements may therefore include inter-granularly bonded hard material grains with a more stable microstructure (e.g., less stressed microstructure) than a polycrystalline compact and cutting element formed without an anneal stage during the HPHT process.
Abstract:
A high-pressure high-temperature cell including two or more thermal insulation layers is described. A high-pressure high-temperature cell including a current path through a thermal insulation layer, the current path being electrically connected to a heating element and having an indirect path through the thermal insulation layer, is also described. High-pressure high-temperature press systems including the foregoing the high-pressure high-temperature cells alone or in combination are also disclosed.
Abstract:
A cartridge assembly for connection to the frame of a high pressure, high temperature press, comprising a front end. The front end may comprise a back up with a conical portion intermediate and coaxial with an anvil and a piston. The anvil may comprise a proximal end in contact with the back-up and a distal end being adapted to form part of a pressurized chamber within the frame. The back-up may comprise a truncated cylinder comprising a first and second interface that are joined by a peripheral cylindrical wall. The cylindrical wall may also comprise a portion extending normally from the periphery of the first interface to a net concave portion of the cylindrical wall. The net concave portion may extend from the normal portion of the cylindrical wall to the periphery of the second interface which abuts the anvil.
Abstract:
A cartridge assembly for connection to the frame of a high pressure, high temperature press, comprising a front end. The front end may comprise a back up with a conical portion intermediate and coaxial with an anvil and a piston. The anvil may comprise a proximal end in contact with the back-up and a distal end being adapted to form part of a pressurized chamber within the frame. The back-up may comprise a truncated cylinder comprising a first and second interface that are joined by a peripheral cylindrical wall. The cylindrical wall may also comprise a portion extending normally from the periphery of the first interface to a net concave portion of the cylindrical wall. The net concave portion may extend from the normal portion of the cylindrical wall to the periphery of the second interface which abuts the anvil.
Abstract:
The present invention includes a hydraulic cartridge and unitary frame connection for a high pressure high temperature press apparatus with the hydraulic cartridge having a cylindrical base and truncated hollow conical section The truncated section has an external threadform with a taper between about 2.650 and 5.650 inches per foot. The unitary frame having an opening with an internal threadform extending axially substantially between an outer surface and an inner reaction chamber defined by the unitary frame and the internal threadform being threadedly mated with the external threadform of the hydraulic cartridge such that a load is substantially equally distributed across the external threadform.
Abstract:
High pressure synthesis of various crystals such as diamond, cBN and the like can be carried out using reaction assemblies suitable for use in methods such as temperature gradient methods. The reaction assembly can be oriented substantially perpendicular to gravity during application of high pressure. Orienting the reaction assembly in this manner can avoid detrimental effects of gravity on the molten catalyst, e.g., convection, hence increasing available volumes for growing high quality crystals. Multiple reaction assemblies can be oriented in series or parallel, each reaction assembly having one or more growth cells suitable for growth of high quality crystals. Additionally, various high pressure apparatuses can be used. A split die design allows for particularly effective results and control of temperature and growth conditions for individual crystals.
Abstract:
The present invention is directed to a method for treating discolored natural diamond, especially Type IIa diamond and Type IaA/B diamond with nitrogen as predominantly B centers, for improving its color. The method includes preblocking and preshaping a discolored natural diamond to prevent its breakage in a high pressure/high temperature (HP/HT) press, placing said discolored natural diamond in a pressure transmitting medium which is consolidated into a pill. Next, the pill is placed into a HP/HT press at elevated pressure and elevated temperature within the graphite-stable or diamond-stable range of the carbon phase diagram for a time sufficient to improve the color of said diamond. Finally, the diamond is recovered from said press. Colorless and fancy colored diamonds can be made by this method.
Abstract:
An anvil for use in ultra high pressure presses capable of operating in the pressure ranges where diamonds, polycrystalline diamond composites and cubic boron nitride are stable, fabricated by diffusion bonding together a plurality of cemented tungsten carbide layers. The anvil has a working layer adjacent to the highest pressure of the press with the remaining plurality of layers behind the working layer for support. The working layer has a higher hardness than the supporting layers and the supporting layers each have higher toughness than the working layer.
Abstract:
THE APPARATUS COMPRISES A PLURALITY OF WEDGES HAVING SURFACE DELIMITING, AT LEAST IN PART, A CLOSED SPACE IN WHICH SOME MATERIAL IS PLACED TO BE COMPRESSED. THE WEDGES ARE CONTIGUOUS WITH EACH OTHER ALONG CONTACT FACES, AND ARE ABLE TO MOVE RELATIVE TO EACH OTHER BY SLIDING OF THESE CONTACT FACES ON EACH OTHER, TO REDUCE THE VOLUME OF THE CLOSED SPACE. THE WEDGES MUTUALLY SUPPORT EACH OTHER ALONG THESE CONTACE FACES. THE CONTACT FACES OF EACH WEDGE DIVERGE TOWARDS THE EXTERIOR OF THE APPARATUS BY A DISTANCE SUFFICIENTLY LARGE SO THAT THE EXTERIOR
PORTIONS OF THESE WEDGES WHICH ARE NOT MUTUALLY SUPPORTED HAVE DIMENSIONS SUFFICIENT TO WITHSTAND THE STRESSES APPLIED DURING OPERATION.