Abstract: A device in a pressure vessel for hot isostatic pressing utilizing a furnace chamber (3) surrounded by a heat insulating member (4), a carrier (5) arranged in the furnace chamber and adapted for carrying loads (6) and which has lateral walls (8) with a space with respect to said member. An arrangement (12) for heating gases present in the furnace chamber is arranged in the bottom region (11) of the chamber and the lateral walls of the carrier are provided with layers (17) having a high heat insulating capacity.

Abstract: A press apparatus for producing dimensionally accurate pressed articles from a particulate material including a frame (70, 73), which can be connected via respective lower and upper connecting devices (71, 72) to a lower and upper platens of a press, a die holding plate (5) arranged in the frame and preferably rigidly connected with the lower connecting device, in which the die holding plate is displaceable relative to a base body (0), a plurality of punch carriers (1-4), at least one of which is supported on the frame between the die holding plate and the base body so as to be displaceable relative thereto into charging and pressing positions by piston/cylinder drives, and supports (12, 22, 32, 42), which in the final press position support the punch carriers relative to the base body.

Abstract: A non-intrusive method of determining temperature and for controlling the Electroconsolidation process is described which is based on the change with temperature of the velocity of sound as it passes through a material. Ultrasonic transducers located outside of the die, but positioned to transmit and receive an ultrasonic signal, are used to determine an average temperature in the line of sight of the transmitted signal. A single-loop feedback system may be used to control the temperature based upon a comparison of the measured temperature to the desired temperature.

Abstract: A fluidizing method transports particulates by gravity flow but passes the particulates through a fluidizer which is partitioned by a porous distributor plate to form first and second chambers and wherein the particulate materials pass through said first chamber which is in gaseous communication with said second chamber via the porous distributor plate. Gas is delivered to the second chamber at a pressure sufficient to generate a gas bearing between the porous distributor plate and the particulate material. The gas is permitted to migrate through the particulate material, but it is then vented to the surrounding atomosphere without causing substantial turbulence in the particulate material and to reduce tendencies for dusting and separation of the particulates into sizes.

Abstract: A gas-assisted flow and filling device for transporting particulate material and filling die cavities includes a source of low-pressure gas for delivering gas to a chamber that is separated from a fluidizing chamber by a porous distributor plate which permits the gas to flow through the particulate material and out a vent screen so that the particulate material is permitted to flow out of the fluidizing chamber essentially free of gas and wherein the pressure of the gas delivered to the fluidizing chamber is sufficient to provide a gas bearing to said particulate material adjacent the distributor plate, but not high enough to cause turbulence in said fluidizing chamber.

Abstract: In a rare earth metal-based alloy powder supplying apparatus, a rare earth metal-based alloy powder is supplied from a feeder box having an opening in its bottom surface into a cavity by moving the feeder box to above the cavity. The apparatus includes a bar-shaped member which is moved horizontally and in parallel in the bottom of the feeder box. A plurality of the bar-shaped members may be provided horizontally at distances. The apparatus further includes a powder replenishing device for sequentially replenishing the alloy powder into the feeder box in an amount corresponding to a decrement in amount resulting from the supplying of the alloy powder from the feeder box to the cavity, an inert gas supply device for filling an inert gas into said powder feeder box, and a plate member made of a fluorine-contained resin and mounted on the bottom surface of the feeder box.

Abstract: A multiple-acting powder metal press is disclosed for making green form double helical gear compacts. The press has inner and outer lower punches, and an upper, outer punch. The upper and lower outer punches have left hand and right hand external helical profiles as chosen to produce a desired helical gear. The punches co-operate with left hand and right hand helical dies carried by the press about the punches. The helical faces require that the dies rotate relative to the punches during operation. A cam and roller mechanism may drive this rotation. The compact forming process commences with an open position in which powder is introduced to a vacant lower die cavity. The upper portions of the press advance downward to close the cavity. All parts of the press except the lower inner, or transfer, punch then move downward at the same speed to transfer powder to the extremities of the cavity. When transfer is complete both lower punches may be stopped, while the upper punches continue to advance.

Abstract: A method for producing a compact of rare earth alloy powder of the present invention includes: a powder-filling step of filling rare earth allow powder in a cavity formed by inserting a lower punch into a through hall of a die of a powder compacting machine; and a compression step of pressing the rare earth alloy powder while applying a magnetic field, the steps being repeated a plurality of times. When the (n+1)th (n is an integer equal to or more than 1) stage compression step is to be carried out, the top surface of a compact produced in the n-th stage compression step is placed at a position above the bottom surface of a magnetic portion of a die.

Abstract: This invention relates to a transformer and more particularly, to a system and method for making a transformer utilizing dynamic magnetic compaction. A coil is placed in a conductive container, and a conductive powder material, such as ferrite, is placed in the container and surrounds the coil and the turns of the coil. A power supply energizes a capacitor which subsequently provides a high energizing current to a second, energizing coil within which the container, material and inner coil are situated, thereby causing the container, powder materials and coil to be compacted to provide an electrical component, such as a transformer, motor, commutator, rotor or choke.

Abstract: Disclosed is a die for compacting a powdered material. The die has a die body having a penetrating die cavity to which a couple of punches are adapted to apply for pressing the powdered material to be supplied to form a compact, and a die holder having a bore into which the die body is shrink fitted. The die cavity is provided with a coating composed of a material which is selected from the group consisting of titanium carbide, titanium nitride, alumina, titanium cyanide, hafnium nitride, chromium nitride, tungsten carbide and DLC, and the die holder is composed of a steel material which is prepared by tempering at a temperature higher than a treatment temperature at which the coating is provided on the die cavity. The die cavity is tapered at a ratio within a range of 1/5,000 to 1/1,000.

Abstract: A sintered powder metal part is prepared for machining by injecting grease into the surface of the part to be machined to a depth at least equal to the depth of machining. The grease is injected under very high pressure using repressing tooling by applying a certain volume of grease between the surface to be machined and the mating tool surface and applying pressure sufficient to uniformly inject the grease into the surface. A rim may be formed in the part adjacent to the surface which acts as a seal during grease injection and is compressed into the part.

Abstract: A method and corresponding device for compacting a powder material into a homogenous article. The method includes the steps of, placing the powder material in a molding cavity connected to a gas source, blowing gas into the lower end of the molding cavity so that the particles in the powder material are suspended in a gas stream, sealing the upper end of the molding cavity by an upper pressing punch, connecting the lower end of the molding cavity to a vacuum source, sealing the connection to the vacuum source by moving a lower punch relative to the lower end portion of the molding cavity, and thereafter compacting the powder material with the help of the pressing punch.

Abstract: Method and device for production of powder metal bodies comprising: introducing powder material (4) in a compacting chamber (4) in a hollow die (1), compacting the material in mainly axial direction in the compacting chamber by urging a first punch (2), axially into said compacting chamber, advancing said first punch (2) further into compacting chamber for further compacting the powder material and imparting upon the die plate (1) a biasing tension, causing the edge portion of the die opening to move under increasing tension in the same direction as the first punch (2), thereby causing opening radial size reduction, causing axial compression also in a direction opposed to that by the first punch (2) by a second punch (3), arranged to move opposed relative the die (1) as compared to that of the first punch (2), and retracting the first punch (2) axially, thereby relieving the hollow die from its biasing and regaining initial form, thereby simultaneously expelling the compact thus formed.

Abstract: External helical teeth of an outer punch member of a lower punch are held in mesh with internal helical teeth of a floating die which is rotatable and floatingly supported. An upper punch is lowered toward a metal powdery material filled in a die cavity space defined by the inner circumferential surface of the floating die and the upper surface of the lower punch. The metal powdery material is compacted into a helical gear blank by the upper and lower punches while external helical teeth of an outer punch member of the upper punch are meshing with the internal helical teeth of the floating die. A presser rod extends downwardly from an upper plate which supports the upper punch forcibly lowers the floating die with respect to the lower punch in a latter period of the powder compacting process.

Abstract: A method and apparatus for embedding features and controlling material composition in a three-dimensional structure (130) is disclosed. The invention enables the control of material characteristics, within a structure (130) made from a plurality of materials, directly from computer renderings of solid models of the components. The method uses stereolithography and solid model computer file formats to control a multi-axis head (480) in a directed material deposition process (123). Material feedstock (126, 127) is deposited onto a pre-heated substrate (19). Depositions (15) in a layer-by-layer pattern, defined by solid models (141, 146), create a three-dimensional article having complex geometric details. Thermal management of finished solid articles (250-302), not available through conventional processing techniques, is enabled by embedded voids (152) and/or composite materials (126, 127), which include dissimilar metals (210, 216).

Abstract: The present invention is a method of automatically loading powder material into a sintering mold and subsequently effecting electrical sintering to the powder material in the sintering mold.

Abstract: An intermediary die 10 is provided with inner circumferential helical teeth r, a lower punch 7 is provided with outer circumferential helical teeth p, and an upper punch 8 is provided with outer circumferential helical teeth q, respectively. When the intermediary die 10, the lower punch 7 and the upper punch 8 all engage to manufacture helical gears by compacting powdered materials, lateral displacement (phase displacement) of a phase guide 11 which is adapted to engage with the upper outer punch 8a, is forcibly corrected to allow it to return to its original position, from the time when the load of the upper outer punch 8a is reduced to when the intermediary die 10 is released. There is also provided an escape surface on the pressing surface of the upper outer punch 8a. The escape surface is designed to reduce the slide contact force developed on a compacted product Ga when the upper outer punch 8a and the compacted product Ga are respectively displaced in a lateral direction.

Abstract: An electric sintering mold includes a clamping portion for clamping a powder material, the material clamped by the clamping portion being subjected to a pressure from a pressurizer and a pulsating electric current externally supplied, so that joule heat is generated within the material for sintering the material. The mold is formed of material containing metal boride having electroconductivity. An electric sintering apparatus using such mold and an electric sintering method utilizing such apparatus and mold are also disclosed.

Abstract: A toolset for forming a component from a powdered metal charge includes a die having two zones on the sidewall. Lubricant is applied to one of the zones. The powdered metal charge is initially compressed to an intermediate density and the lubricated zone of the sidewall brought into contact with the partially compressed charge. The charge is then further compressed to a final density.

Abstract: An improved powder-compacting method and apparatus designed to require a reduce level of a pressurizing force for powder compacting by utilizing an elastomeric plate for compaction, thereby allowing powder to be compacted by means of a smaller-scaled compacting apparatus instead of a larger-scaled compacting apparatus.

Abstract: A rare-earth alloy powder pressing apparatus comprises a die. The die includes a die main body. The die main body includes a through hole for formation of a cavity, and an auxiliary yoke. A rare-earth alloy powder is fed into the cavity. A correcting yoke is disposed near the die, on a side from which a compact is taken out, and an orienting magnetic field is applied. At this time, the correcting yoke is disposed on an upper side of the die if the compact is to be taken out from the upper side of the die whereas the correcting yoke is disposed on a lower side of the die if the compact is to be taken out from the lower side of the die, an inward side surface of the correcting yoke and an inward side surface of the auxiliary yoke are made flush with a plane vertical to a direction in which the orienting magnetic field is applied, and the correcting yoke is urged toward the die. Then, the rare-earth alloy powder is pressed by an upper punch and a lower punch to form a compact.

Abstract: A method and corresponding device for compacting a powder material into a homogenous article. The method includes the steps of, placing the powder material in a molding cavity connected to a gas source, blowing gas into the lower end of the molding cavity so that the particles in the powder material are suspended in a gas stream, sealing the upper end of the molding cavity by an upper pressing punch, connecting the lower end of the molding cavity to a vacuum source, sealing the connection to the vacuum source by moving a lower punch relative to the lower end portion of the molding cavity, and thereafter compacting the powder material with the help of the pressing punch.

Abstract: The present invention relates to a device for forming tubular articles from powder material including an upper pressing punch, a lower punch, a core pin and a matrix having an inner periphery corresponding to the outer periphery of the upper and lower punch, a molding cavity being defined between the upper and lower punch, the core pin and the matrix, whereby the core pin is movable in relation to the matrix. According to the invention the upper pressing punch is arranged to actuate movement of the core pin or the matrix during compacting of a powder in the molding cavity so that the pressing punch and the core pin or the matrix move together.

Abstract: The eccentric press for pressing of machined parts out of powdery material using a drawing-off procedure, comprises a driving motor, an actuation for an eccentric pinion gear with a worm drive shaft as well as at least two columns, one tie-bar and a press mechanism with a pressing mold, wherein the motor (2) is accommodated in front of, above or in the vertical axis beside the worm drive shaft (3) and wherein the oil pump (6) is essentially arranged on the same level as the worm drive shaft (3).

Abstract: A process of forming a sintered article of powder metal comprising blending graphite, Si carbide and lubricant, with pre-alloyed iron base powder; pressing said blended mixture to a shaped article; sintering said article in a reduced atmosphere; forced cooling said sintered article.

Abstract: A process and apparatus for separating briquettes and fragments in a product stream resulting from briquetting direct reduced iron. Separating and cooling of the briquettes and fragments are carried out simultaneously in an initial step with use of separating means submerged in a cooling bath. The process enables use of less rugged apparatus following the initial step and the apparatus is not subjected to handling the product stream at the elevated temperatures at which briquetting is carried out. Capital expenditure and equipment maintenance is thus reduced.

Abstract: A densified sintered product, such as a rolling cutter adapted for use in a steel tooth rolling cutter earth boring bit, has a layer of a metal powder applied to the external surface of the unsintered compact, the metal powder being melted to form a thin glaze of the melted metal powder on the external surface of the sintered compact, and the sintered compact may then be pneumatically isostatically forged.

Abstract: The present invention aims to prevent heating and ignition of a material powder of a rare-earth alloy while reducing the oxygen content thereof so as to improve the magnetic properties of the rare-earth magnet. A rare-earth alloy powder is compacted by using a powder compacting apparatus including: an airtight container capable of storing a rare-earth alloy powder therein; an airtight feeder box moved between a powder-filling position and a retracted position; and an airtight powder supply device capable of supplying the rare-earth alloy powder from the container into the feeder box without exposing the rare-earth alloy powder to the atmospheric air.

Abstract: A powder pressing apparatus comprises a die having a through hole, an upper punch and a lower punch. At least one of the upper and lower punches has a punching surface having an edge portion provided with a projection. The projection has a tip chamfered by a width not greater than 0.5 mm. The punching surface has a slope having a surface roughness Ra not greater than 1.0 &mgr;m. A rare-earth alloy powder is fed into a cavity formed in the through hole of the die. The rare-earth alloy powder in the cavity is oriented by magnetic field, and pressed by using the upper and lower punches. The upper punch and the lower punch are brought closest to each other at a minimum distance not smaller than 1.7 mm during the pressing. An obtained compact is used for manufacture of a sintered body and a voice coil motor.

Abstract: A forming apparatus comprises a die formed with a through hole for provision of a cavity. A feeder box stored with a raw material powder having an average grain diameter of 0.1 &mgr;m˜500 &mgr;m is positioned above the cavity of the die, and the raw material powder is allowed to fall into the cavity while an inside of the feeder box and an inside of the cavity are each maintained at a pressure not greater than 10 kPa. During the supply of the raw material powder, the feeder box may be vibrated, or the supply may be made via a hose. The raw material powder may be a granulated powder or a rare-earth alloy powder. The raw material powder supplied in the cavity is pressed by an upper punch and a lower punch into a compact.

Abstract: This invention relates to a device to compact parts with an undercut out of powder material having an upper die moveable relative a lower die, at least one upper punch associated with the upper die for relative movement therebetween, at least two lower punches associated with the lower die for relative movement therebetween, the lower punches defining a lower cavity with the lower die for filling with the powder material when the dies are in an open position, the upper die contacting the lower die in a closed position for movement of one of the lower punches towards the upper die so as to transfer the powder material towards the upper die and then to compact the powder material between the upper and lower punches with said dies in the closed position so as to produce the part; the dies moveable to an eject position for ejection of the compacted part.

Abstract: An apparatus for bonding a particle material to near theoretical density, includes a chamber, a punch and die assembly for supporting a particle material, plungers for applying shear and/or axial pressures, and a power supply for applying a current. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps. is applied. The apparatus may be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material.

Abstract: In a rare earth metal-based alloy powder supplying apparatus, a rare earth metal-based alloy powder is supplied from a feeder box having an opening in its bottom surface into a cavity by moving the feeder box to above the cavity. The apparatus includes a bar-shaped member which is moved horizontally and in parallel in the bottom of the feeder box. A plurality of the bar-shaped members may be provided horizontally at distances. The apparatus further includes a powder replenishing device for sequentially replenishing the alloy powder into the feeder box in an amount corresponding to a decrement in amount resulting from the supplying of the alloy powder from the feeder box to the cavity, an inert gas supply device for filling an inert gas into said powder feeder box, and a plate member made of a fluorine-contained resin and mounted on the bottom surface of the feeder box.

Abstract: A press for making compacts out of raw material such as metal powder is disclosed. The press includes a removable picker system. The picker system has an elongate guide rail element and a gripper assembly fixed to a slide mounted on the guide rail. The gripper assembly may move toward and away from a die in the press platen to pick up and move a compact that has been ejected from the die. The gripper assembly has gripper arms and gripper fingers that move toward and away from a central vertical longitudinal plane that runs through the center of the die. The guide rail provides the sole support for the gripper assembly, and the guide rail is offset from the central vertical longitudinal plane. The picker system allows access to the die for inspection, cleaning or changing of the die without removing the picker system; the gripper assembly can be moved down the guide rail element away from the die to provide access to the die.

Abstract: Method and apparatus for forming a raised gripping surface along the peripheral edge of poured aggregate swimming pool coping. Utilized therein is a form board including a recess to form a first portion of the gripping surface and an aggregate dispensing mule to form a second portion of the gripping surface in a contiguous relation to the first portion. A finishing tool joins both portions into a combined unitized structure.

Abstract: A spiral bevel gear having right and left tooth flanks having such a small pitch angle that either right or left ones are not seen in plan from the apex side of cone is molded by a powder molding device so as not to interfere with a die of the device when removed from the die. The die has teeth for molding and is rotatably supported. A fixed guide mechanism for guiding the die is provided. Guide portions of the guide mechanism have a predetermined lead so that the die is rotated guided by the guide portions when the molded article is punched out of the die. Thus, the teeth formed on the molded article reliably disengage from the teeth for molding. This makes it possible to reliably punch the molded article out of the die.

Abstract: A powder feed system for delivering a quantity of particulate material to a die cavity of a powder press is provided. The powder press has a table-like platen surface which is flush with and surrounds a die in which the die cavity sits, an upper punch appending from an upper ram and a lower punch. The powder feed delivery system includes a receptacle for receiving and delivering particulate material to the cavity. The receptacle has an ingress through which particulate material is received under pressure and an egress for registering with the interior of the cavity and through which particulate material is delivered under pressure from a feed conduit to the cavity. The feed conduit is attached at a first end to the receptacle ingress. At least one pressure generator is attached to a top end of a pressure vessel attached at a second end to the feed conduit.

Abstract: A press for compacting raw material into compacted elements is disclosed. The press has a vertically movable platen and a feed shoe on the platen. The feed shoe is urged against the platen by a pair of force-transmitting devices and lever arms. The lever arms are also connected to a frame. The frame is vertically fixed, and the lever arms pivot on the frame as the feed shoe and platen move vertically. The feed shoe is movable horizontally on the platen between a feed position overlying a bore and die in the platen and a press position horizontally spaced from the bore and die. The frame, force-transmitting devices and lever arms all move horizontally with the feed shoe. The assembly is moved horizontally by a linear drive mechanism. A pair of supplemental support rods are connected to the frame to relieve stress on the linear drive mechanism and to stabilize the frame.

Abstract: A raw material delivery system is disclosed. It is used with a press of the type used to compact raw material in a die. The press has a horizontal table with an opening in which the die is held. A feed shoe is movable across the table between an extended position where a central bore of the feed shoe overlies the die and a retracted position. In one embodiment, a vertically movable feed tube is carried on a bridge, and has a passage through which raw material may pass. The vertically movable feed tube receives raw material from a vertically fixed feed tube received telescopically within the vertically movable feed tube. A valve is between the two feed tubes. A valve may be provided between the bridge and the feed shoe so that the raw material passes through this interface without being exposed to cross-ventilation.

Abstract: A sliding frame press utilizing a single pressure generating actuator to simultaneously apply the same uniform load to opposite sides of a workpiece. Two posts integral to sliding frame part 2 are freely and movably supported at the upper surface and within a post guide part located at both sides of frame base 5. Pressure is exerted on pressure rod 7 by the force applied at actuator 6. When the pressure applied to pressure rod 7 by actuator 6 exceeds the free weight of sliding frame part 2, a reactive force generated from pressure rod 7 operates to raise sliding frame part 2, thus simultaneously applying a uniform load to opposing sides of the workpiece located between pressure rod 7 and the lower punch 9 operatively connected to the sliding frame part 2.

Abstract: A multi-stage forming tool for densifying the outer perimeter of post-sintered powder metal preforms includes a series of axially spaced die plates having different sized die openings arranged from largest to smallest. An oversized powder metal preform it is forced by a punch through the successive die openings causing the outer perimeter material to be displaced and densified. The space between successive dies allows for elastic recovery of the preform to maximize the compressive stress imparted to the preform at each die stage. A high density, high strength powder metal component results which is suitable as a replacement for wrought components in high strength applications such as transmission gears.

Abstract: In the case where an upper punch and a die are made rotatable, a lower punch that is fixed in a conventional example is rotatably supported. Further, a guide mechanism with fixed helical lead for guiding the die is constructed of a guide whose lead is identical to a lead of helical gear contour, and a cam follower that engages with the guide. The guide and the cam follower are arranged so as to correspond to the die and a part with fixed helical lead that is a newly arranged component in the invention. The meshed portion between the helical gear contours of the upper and lower punches and helical gear contours formed on a die or a core rod is free from any excessive force even when a lead-phase shift occurs between helical gears formed on upper and lower punches due to the flexing of the punches during compression.

Abstract: A powder delivery system for delivering an electrode powder to a compaction device where the powder is compressed onto an electrically conductive substrate, the powder delivery system comprises a powder feed channel which is vibrated to effect powder movement therethrough and delivery therefrom. An accelerometer is coupled to the powder feed channel for measuring the acceleration of the channel as it vibrates. The actual measured acceleration is used to control the vibration of the channel.

Abstract: A mold for molding a drum shaped magnetic core having two flanges connected by a coil winding core portion. The mold includes a die defining a cylindrical cavity having an inner diameter substantially equal to an outer diameter of the flanges. A pair of die inserts are movable in an orthogonal direction relative to the cylindrical cavity and define a diameter of the coil winding core portion of the drum shaped magnetic core. The diameter of the coil winding core portion is smaller than the outer diameter of the flanges. An upper punch and a lower punch are inserted into the cylindrical cavity from a corresponding end opening of the mold such that each forms a flange. A central punch is disposed coaxially within one of the punches to form the coil winding core portion.

Abstract: A device including an injection molding tool for use once or a few times for producing a sinterable ceramic and/or metallic product. The device includes at least one first tool part. At least one second tool part is combinable with the at least one first tool part to form a molding space for the product. The second tool part is produced using a wet composition and is made of a readily worked and form-stable material containing pores and admixed heat-conducting particles. A wet composition-enclosing member can engage the first tool part during the production of the second tool part. A unit can be connected to the at least one second tool part and can be arranged with the at least one first tool part for absorbing internal lateral displacement forces arising during squeezing or injection of an injection molding composition.

Abstract: A method of producing a contact element having a base body made of material with good electrical conductivity (first material) and a contact layer made of material with a less good electrical conductivity which is resistant to arc erosion (second material), includes impregnating a sinter structure of the contact layer with the material of the base body. The base body and the sinter structure are placed one above the other in a cup-like mold and are heated therein to above the melting temperature of the first material but still below the melting temperature of the second material, so that the first material fuses and penetrates into the sinter structure. The sinter structure may be produced by scattering the second material in powder form onto the first material and initially sintering in a degassing process below the melting temperature of the first material. It is also possible to produce the sinter structure in advance and to place a green body on the base body.

Abstract: An apparatus for manufacturing a pressed powder body has a die assembly comprising an upper die and a lower die, for pressing an unpressed powder body of a material powder filled on a pressing surface of the lower die, into a pressed powder body between the upper die and the lower die, at least one of the upper die and the lower die being vertically movable to press the unpressed body, and a powder increasing mechanism for increasing an amount of the material powder locally in the unpressed powder body. The powder increasing mechanism comprises at least one of the upper die and the lower die, the at least one of the upper die and the lower die comprising a first die member for pressing a first portion of the unpressed powder body at a first time and a second die member for pressing a second portion of the unpressed powder body at a second time which is different from the first time.

Abstract: A method and apparatus for fabricating high density monolithic metal and oy billets. The process requires preheating precursor materials of metal or alloy billets by means of a combustion synthesis called Self-Propagating High-Temperature Synthesis (SHS). The reaction takes place in an insulated reaction vessel where the precursors, in a powder form, are heated to high temperatures. The precursors are then compacted to high density by means of pressure waves generated by detonation of an explosive. The method is capable of producing high purity tungsten and tungsten-based alloys of greater than 90% theoretical density.

Abstract: An apparatus for bonding a particle material to near theoretical density, includes a chamber, a punch and die assembly for supporting a particle material, plungers for applying shear and/or axial pressures, and a power supply for applying a current. In the first stage, a pulsed current of about 1 to 20,000 amps., is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a shear force of about 5-50 MPa is applied. In the second stage, an axial pressure of about less than 1 to 2,000 MPa is applied to the particle material for a predetermined time period, and substantially simultaneously therewith, a steady current of about 1 to 20,000 amps. is applied. The apparatus may be used to bond metallic, ceramic, intermetallic and composite materials to near-net shape, directly from precursors or elemental particle material without the need for synthesizing the material.

Abstract: A pressurized feed shoe for delivering particulate materials to fill a die cavity is provided. The feed shoe includes a feed shoe body comprising a vessel for receiving a quantity of particulate material. The feed shoe body has at least one bottom egress opening for registering with the die cavity and a top ingress opening for receiving particulate material. A pressure generator for generating supra-atmospheric pressures within the vessel and the die cavity is also provided. The pressure generator communicates with the vessel via a conduit sealingly engaged thereto. A shuttle selectively moves the feed shoe body to and from a position whereby the bottom egress opening registers with the die cavity.