Abstract:
A polycrystalline diamond (PCD) compact and method for making the compact are provided. The method includes bringing a first PCD wafer and a second PCD wafer together at an interface in the presence of a bonding agent to form an unbonded assembly and bonding the wafers together at the interface at a pressure and temperature at which diamond is thermodynamically stable. The first PCD wafer is more thermally stable than the second PCD wafer.
Abstract:
A riser includes a housing in communication with a entry conduit and an exit conduit. The housing is defined by a holdup chamber having a volume of between about 1133 liters and about 45307 liters. The riser is designed to receive a hydrocarbon feed and a catalyst. An apparatus for fluid catalytic cracking includes a riser in fluid communication with a reactor vessel. A hydrocarbon feed stream and a catalyst travel through a first section of the riser at a first velocity of between about 1.5 msec to about 10 msec and through a second section of the riser at a second velocity of more than about 15 msec. A process for fluid catalytic cracking uses a riser with a holdup chamber. A hydrocarbon feed and a catalyst decrease in velocity in the holdup chamber to between 1.5 msec and 10 msec.
Abstract:
The present invention relates to a method for producing diamond-metal composites comprising mixing diamond particles with metal-filler particles forming a diamond/metal-filler mixture, forming a green body of the diamond/metal-filler mixture, optionally green machining the green body to a work piece before or after pre-sintering by heating the green body to a temperature ≦500° C., infiltrating the green body or the work piece with one or more wetting elements or infiltrating the green body or the work piece with one or more wetting alloys, which infiltration step being carried out under vacuum or in an inert gas atmosphere at a pressure ≦200 Bar. The invention relates further to a green body, a diamond metal composite, and use of the diamond metal composite.
Abstract:
A method of producing a composite diamond compact comprising a polycrystalline diamond (PCD) compact bonded to a cemented carbide substrate is provided. The method includes the steps of: providing a PCD table, preferably a PCD table with diamond-to-diamond bonding and a porous microstructure in which the pores are empty of second phase material bringing together the PCD table and a cemented carbide substrate in the presence of a bonding agent to form an unbonded assembly; subjecting the unbonded assembly to an initial compaction at a pressure of at least 4.5 GPa and a temperature below the melting point of the bonding agent for a period of at least 150 seconds; and thereafter subjecting the unbonded assembly to a temperature above the melting point of the bonding agent and a pressure of at least 4.5 GPa for a time sufficient for the bonding agent to become molten and bond the PCD table to the substrate to form a composite diamond compact.
Abstract:
A solid-state far ultraviolet light emitting element is formed by a hexagonal boron nitride single crystal, excited by electron beam irradiation to emit far ultraviolet light having a maximum light emission peak in a far ultraviolet region at a wavelength of 235 nm or shorter.
Abstract:
A multiple anvil press can be configured for gem-quality growth. The press can include a plurality of opposing anvils, where the anvils are configured for simultaneous movement within a tolerance of less than about 0.5 mm as measured at each anvil surface, and each anvil can be aligned to a common center of all the anvils where the alignment is tuned to a tolerance of less than about 0.1 mm during use. The press can also include a reaction volume formed by the enclosure of all anvils, where the reaction volume has a size configured to facilitate single crystal growth per cycle time.
Abstract:
The invention relates to a method for debindering and/or purifying granules or material suitable for use in High Pressure High Temperatures diamond or cubic boron nitride synthesis, the method comprising the steps of passing the granules or material through a zone having controlled atmosphere and temperature in a continuous manner, the zone having a maximum temperature within the zone of greater than approximately 600° C, wherein the time spent by each granule within the zone is less than 30 minutes.
Abstract:
Methods of synthesizing superabrasive particles such as diamonds and cubic boron nitride are disclosed and described. One procedure includes providing a superabrasive precursor including a source material in a metal matrix. The carbon source can contain a majority of carbon atoms oriented in a rhombohedral polytype configuration. A shock wave can be passed through the carbon source that is sufficient to convert the diamond to graphite. The superabrasive precursor can be formed by dissolving hexagonal carbon in a suitable molten metal or by mixing particulate components. Similarly, hexagonal boron nitride can be used in a metal matrix which is subjected to a shock wave having sufficient energy to form cubic boron nitride. The superabrasive particles produced using these methods can be provided at relatively high yields with reduced costs.
Abstract:
A material treatment heater tube is provided in which the axial thermal conductivity is less than 10% of the circumferential thermal conductivity.