Abstract: The disclosure discloses a magnesium alloy material smelting device, comprising a furnace, a disc packing device, the disc packing device comprising a stirring shaft, a packing basket, a disc stirring head, the stirring shaft connected with a packing basket, the bottom of the packing basket connected with a disc stirring head, the disc stirring head comprising a plurality of stirring wings, the stirring wings connected with the packing basket and the stirring disc, the connecting ends of the stirring wings connected with each other, the stirring ends extending to the edge of the stirring disc, and the sidewall of the packing basket provided with a liquid passage hole; during the process of preparing and processing the magnesium alloy, the disc stirring head may accelerate the diffusion, the rotation of the disc stirring head may divide the melt into upper and lower layers, and the upper layer of the melt forms a solution vortex to accelerate the diffusion of the master alloy elements; the lower melt keeps rel

Abstract: This disclosure provides a voltammetric measurement system predicated on a mercury electrode. To minimize mercury consumption and/or disposal, the disclosed system includes a recirculatory system and mechanisms for cleaning mercury that permit mercury to be reclaimed, purified and reused on a nearly indefinite basis. Optional embodiments provide a modular design including a specially designed measurement cell, and for an automated control system to facilitate these ends.

Abstract: A stirring device includes a stirring unit, a gas supplying unit, and a feeding unit. The stirring unit includes a drive mechanism and a shaft member. The shaft member includes a hollow rotary shaft coupled to be driven by the drive mechanism to rotate, and a stirring head coupled to rotate with the hollow rotary shaft. The gas supplying unit includes a gas supply, and a piping member fluidly communicating with the gas supply and the shaft member. The feeding unit includes a storage tank and a feeding tube fluidly communicating with the storage tank and the shaft member.

Abstract: A furnace assembly for a metal-making process, including: an electric arc furnace configured for flat bath operation and having a bottom, and an electromagnetic stirrer configured to be arranged underneath the bottom of the electric arc furnace to enable stirring of molten metal in the electric arc furnace.

Abstract: Provided are a molten metal refining device and method. The molten metal refining method includes: preparing molten metal; dipping an impeller into the molten metal; supplying a liquid dephosphorization agent on top of the molten metal; and stirring the molten metal by rotating the impeller, wherein a solid dephosphorization agent in a powder state is supplied through the lower portion of the impeller in the stirring of the molten metal, thereby improving the stirring efficiency of the molten metal and efficiently controlling the phosphorus concentration in the molten metal.

Abstract: A system for applying tension to a component for use in molten metal processing. Preferably, the component includes an outer core and at least one tension rod positioned partially within the outer core. The component is preferably elongated, such as a support post or an impeller shaft. The tension rod applies compression to the outer cover, which makes the outer cover more resistant to breakage if it strikes, or is stricken by, an object.

Abstract: A system for applying tension to a component for use in molten metal processing. Preferably, the component includes an outer core and at least one tension rod positioned partially within the outer core. The component is preferably elongated, such as a support post or an impeller shaft. The tension rod applies compression to the outer cover, which makes the outer cover more resistant to breakage if it strikes, or is stricken by, an object.

Abstract: A device for dispersing gas into molten metal includes an impeller, a drive shaft having a gas-transfer passage therein, and a first end and a second end, and a drive source. The second end of the drive shaft is connected to the impeller and the first end is connected to the drive source. The impeller includes a first portion and a second portion with a plurality of cavities. The first portion covers the second portion to help prevent gas from escaping to the surface without entering the cavities and being mixed with molten metal as the impeller rotates. When gas is transferred through the gas-transfer passage, it exits through the gas-release opening(s) in the bottom of the impeller. At least some of the gas enters the cavities where it is mixed with the molten metal being displaced by the impeller. Also disclosed are impellers that can be used to practice the invention.

Abstract: Apparatus and methods for industrial-scale production of metal matrix nanocomposites (MMNCs) are provided. The apparatus and methods can be used for the batch production of an MMNC in a volume of molten metal housed within the cavity of a production chamber. Within the volume of molten metal, a flow is created which continuously carries agglomerates of nanoparticles, which have been introduced into the molten metal, through a cavitation zone formed in a cavitation cell housed within the production chamber.

Abstract: A system and method for transferring molten metal from a vessel and into a launder is disclosed. The system includes at least a vessel for containing molten metal, an overflow (or dividing) wall, and a device or structure, such as a molten metal pump, for generating a stream of molten metal. The dividing wall divides the vessel into a first chamber and a second chamber, wherein part of the second chamber has a height H2. The device for generating a stream of molten metal, which is preferably a molten metal pump, is preferably positioned in the first chamber. When the device operates, it generates a stream of molten metal from the first chamber and into the second chamber. When the level of molten metal in the second chamber exceeds H2, molten metal flows out of the vessel and into the launder. The launder has a horizontal angle of between 0° and ?10° to help prevent dross from being pulled by gravity into downstream vessels.

Abstract: Apparatus and methods for industrial-scale production of metal matrix nanocomposites (MMNCs) are provided. The apparatus and methods can be used for the batch production of an MMNC in a volume of molten metal housed within the cavity of a production chamber. Within the volume of molten metal, a flow is created which continuously carries agglomerates of nanoparticles, which have been introduced into the molten metal, through a cavitation zone formed in a cavitation cell housed within the production chamber.

Abstract: A system for adding gas to and transferring molten metal from a vessel and into one or more of a ladle, ingot mold, launder, feed die cast machine or other structure is disclosed. The system includes at least a vessel for containing molten metal, an overflow (or dividing) wall, a device or structure, such as a molten metal pump, for generating a stream of molten metal, and one or more gas-release devices.

Abstract: A device for dispersing gas into molten metal includes an impeller, a drive shaft having a gas-transfer passage therein, and a first end and a second end, and a drive source. The second end of the drive shaft is connected to the impeller and the first end is connected to the drive source. The impeller includes a first portion and a second portion with a plurality of cavities. The first portion covers the second portion to help prevent gas from escaping to the surface without entering the cavities and being mixed with molten metal as the impeller rotates. When gas is transferred through the gas-transfer passage, it exits through the gas-release opening(s) in the bottom of the impeller. At least some of the gas enters the cavities where it is mixed with the molten metal being displaced by the impeller. Also disclosed are impellers that can be used to practice the invention.

Abstract: Disclosed are degassers, couplings, impeller shafts and impellers for use in molten metal. One such coupling transfers gas into an impeller shaft, the coupling having a smooth, tapered internal surface to align with a corresponding surface on the impeller shaft and help prevent gas leakage and to assist in preventing damage to the impeller shaft. Improved impellers for shearing and mixing gas are also disclosed, as is a degasser including one or more of these components.

Abstract: Apparatus and methods for industrial-scale production of metal matrix nanocomposites (MMNCs) are provided. The apparatus and methods can be used for the batch production of an MMNC in a volume of molten metal housed within the cavity of a production chamber. Within the volume of molten metal, a flow is created which continuously carries agglomerates of nanoparticles, which have been introduced into the molten metal, through a cavitation zone formed in a cavitation cell housed within the production chamber.

Abstract: A system for applying tension to a component for use in molten metal processing. Preferably, the component includes an outer core and at least one tension rod positioned partially within the outer core. The component is preferably elongated, such as a support post or an impeller shaft. The tension rod applies compression to the outer cover, which makes the outer cover more resistant to breakage if it strikes, or is stricken by, an object.

Abstract: A device for releasing gas into molten metal includes a base having a discharge. The discharge has a first section including a first cross-sectional area and a second section including a second cross-sectional area, wherein the first section is upstream of the second section and the first cross-sectional area is smaller than the second cross-sectional area. A gas-release opening is positioned so that it can release gas into one or more of the first section or the second section. As the molten metal moves from the first cross-sectional area to the second cross-sectional area gas is released into the molten metal and the molten metal flow helps to draw the gas into the flow, thereby lowering the pressure required to release gas into the molten metal. Metal-transfer conduits other than a discharge incorporated in a pump base are also disclosed, as are pumps including either a discharge or other metal-transfer conduit according to the invention.

Abstract: An exemplary embodiment of the invention provides a side well for a metal melting furnace. The side well comprises an insulated body having a front wall adapted to form part of an insulated side wall of a metal melting furnace and a top, a cavity within the body including a single upright well having a cylindrical wall adjacent to a closed bottom of the cavity, an entrance to the cavity at the top of the insulated body, a metal inlet channel leading directly into the cavity from an inlet aperture in the front wall, and a metal outlet channel leading directly from the cavity to a metal outlet aperture in the front wall. The side well includes a rotatable impeller having a vertical rotatable shaft and at least one vaned section positioned at a lower end of the rotatable shaft; wherein the impeller extends into the cavity with the vaned section positioned in the well adjacent to the cylindrical wall.

Abstract: A coupling assembly includes a motor driven drive shaft. A rotatable refractory shaft is adapted to be connected to a rotor. Locking recesses are formed in an upper end of the refractory shaft. A rotatable coupling includes a body and a device for affixing the drive shaft to the body. Lever arms are fastened to the body and can be pivoted. A recess in the body receives the refractory shaft. Openings in the body extend from an exterior surface of the body to the recess. Each of the lever arms includes a protruding locking member positioned in the opening in the body. Each locking member engages a locking recess. A device exerts a force against the lever arms forcing the locking members into the locking recesses.

Abstract: An impeller for dispersing gas into molten metal includes a rectangular prism body having upper and lower faces and four side walls. The body has an opening extending through the upper and lower faces and defines a hub around the opening on the upper face. The impeller further includes a plurality of elongate grooves extending radially outwardly from the hub.

Abstract: A method of adjusting a vortex of molten metal comprises providing a scrap charging vessel. The scrap charging vessel includes a vortex control plate having an outlet orifice that can be positioned at a bottom of the vessel so that the outlet orifice is in fluid communication with an outlet passageway of the vessel. A vortex level is estimated or observed. A size of the outlet orifice of the vortex control plate is selected that can produce a desired level of a vortex in the vessel that is the same as or different than the estimated or observed vortex level. The vortex control plate of the selected outlet orifice size is positioned in the vessel. Molten metal is moved into an inlet opening of the vessel and forms the vortex at the desired level in the vessel.

Abstract: The present invention describes an apparatus and a process for in-line substantially continuous degassing of aluminium and/or aluminium alloys, in absence of chlorine and through the injection of at least one metal halide salt that includes a halogen and water and an inert gas, in a transfer trough before casting.

Abstract: A method of preparing bismuth oxide and an apparatus therefor are disclosed. The method includes: melting bismuth metal; transporting the melted bismuth metal to an open first reactor and oxidizing the melted bismuth metal while stirring at a temperature of 300-650° C.; and transporting bismuth oxide and un-reacted material to a closed second reactor through a screw and oxidizing the bismuth oxide and un-reacted material while rotating the closed second reactor at a temperature of 300-600° C. with a supply of air or oxygen.

Abstract: An agitator for applying an alternating field to a melting furnace main body in order to melt a row material to form a melt includes a plurality of magnets, which are arranged so that magnetic lines of force emitted from one of the magnets pass through the melt in the melting furnace main body and return to another magnet, the magnets being fixed to an inclined surface which is inclined by an angle with respect to a horizontal surface, and being rotatable around an axis substantially perpendicular to the inclined surface.

Abstract: A process for producing foamed aluminum in space comprising the steps of: heating aluminum until it is molten; applying the force of gravity to the molten aluminum; injecting gas into the molten aluminum to produce molten foamed aluminum; and allowing the molten foamed aluminum to cool to below melting temperature. The apparatus for carrying out this invention comprises: a furnace which rotates to simulate the force of gravity and heats the aluminum until it is molten; a door on the furnace, which is opened for charging the aluminum into the furnace, closed for processing and opened again for removal of the foamed aluminum; a gas injection apparatus for injecting gas into the molten aluminum within the furnace; and an extraction apparatus adjacent the door for removing the foamed aluminum from the furnace.

Abstract: The invention relates to a rotary device for dispersing a gas in a molten metal. The device comprises a hollow shaft at one end of which is attached a rotor. The rotor has a roof and a base which are spaced apart and connected by a plurality of vanes. A compartment is defined between each adjacent pair of vanes and the roof and the base, and each compartment has an inlet and first and second outlets. A flow path is defined through the shaft into the inlets of the compartments and out of the first and second outlets. Each first outlet is disposed radially outwardly of the respective inlet and arranged to disperse gas laterally of the rotor in use, and each second outlet is disposed in the roof of the rotor and arranged to disperse gas upwardly from the rotor in use.

Abstract: A spout opening cleaner for cleaning smelt spouts of recovery boilers and the like includes an actuation arm and self-aligning cleaning head. The cleaning head employs open bail designs for enabling continued flow of smelt during a cleaning cycle.

Abstract: A scrap melter for light gage metal scrap includes a shrouded impeller connected to a shaft, the shaft connected to a rotary power device. The shrouded impeller is immersed in a molten metal pool in a charge bay or furnace. It is inclined at an angle relative to the vertical. The shrouded impeller creates a vortex in the molten metal pool, which includes a whirlpool at the surface of the molten metal. The center of the whirlpool is horizontally displaced from the shaft so that scrap can be charged into the whirlpool to be ingested into the vortex. The shrouded impeller creates a vortex for scrap ingestion and pumps molten metal for re-circulation through the melting system without the need of a separate pump.

Abstract: A method of dispersing flux in molten metal includes providing a source of flux powder and a source of gas. An impeller is disposed on an end of a shaft inside the impeller chamber of a base made of heat resistant material. The base is submerged in the molten metal and includes a molten metal inlet opening into the impeller chamber and a molten metal discharge passageway extending from the impeller chamber to an exterior of the base. Molten metal is drawn through the inlet opening into the impeller chamber by rotation of the impeller in the impeller chamber. The molten metal is moved out of the impeller chamber through the discharge passageway by the rotation of the impeller. A discharge stream of molten metal travels through the discharge passageway into the molten metal exterior to the base. The gas flows from the gas source into a refractory flux conduit. The flux conduit extends from outside the molten metal into fluid communication with the discharge passageway.

Abstract: The present invention relates to a powder fabricating apparatus. It is an object of the present invention to provide the powder fabricating apparatus, which is capable of obtaining metal powder in a rapid and continuous fashion, various kinds of oxide, or alloy powder. The powder fabricating apparatus for achieving the object of the present invention comprises a barrel wherein an inlet and an outlet are formed at both opposite ends thereof, respectively; a screw which is rotationally mounted in the barrel and by which reactant supplied from the inlet moves toward the outlet; a driving portion for causing a relative rotational motion between the screw and the barrel; reaction control means for controlling reaction conditions of the reactant which moves in the barrel; and a controller for controlling the driving portion and the reaction control means.

Abstract: The present invention features a multi-functional pump for pumping molten metal, which includes a base that is submerged in molten metal having at least two impeller chambers. The base includes one or more inlet openings and one or more outlet openings. Each outlet opening leads from one of the impeller chambers. The invention enables the impeller to be moved to a position to rotate in either impeller chamber or while straddling impeller chambers. This enables the pump to have the versatility to operate in a circulation mode; a transfer mode; two or more circulation modes; two or more transfer modes; and a combination of transfer and circulation modes. The impeller chambers can be stacked over each other and the impeller can be moved vertically in and between impeller chambers.

Abstract: A vortexer apparatus including a vessel comprising an exterior surface, an interior surface and a mouth for receiving material at an upper end of the interior surface. An outlet passageway extends downwardly from the interior surface. An inlet opening is located between the interior and exterior surfaces above the outlet passageway. The inlet opening is offset from the center line of the interior surface. A pump is adapted to pump fluid into the vessel to form a vortex in the vessel. The base and impeller of the pump are configured and arranged effective to provide molten metal leaving the base with a positive pressure. An outlet conduit extends from the base outlet to near the vessel inlet opening and can be maintained at a temperature above which molten metal solidifies, along it's entire length.

Abstract: A system for producing a metal foam comprises a bath containing a molten metal, a rotating shaft or impeller extending through the base of the bath into, and submerged in the molten metal, and a gas discharge nozzle provided on the submerged end of the shaft. The opposite end of the shaft is connected to a gas supply line and the shaft is rotated with a motor. A seal is provided at the opening in the base of the bath for preventing leakage of the molten metal there-through.

Abstract: A device for use in a molten metal pump helps alleviate jams between a rotating rotor and stationary inlet. The device includes an inlet structure including one or more openings and a displacement structure that preferably includes one or more rotor blades. The inlet structure and displacement structure are connected to one another (preferably, but not necessarily, as a unitary piece), thus enabling them both to rotate. A pump including the device is also enclosed. The invention further includes a bearing surface for an impeller or for a device according to the invention, wherein the bearing surface includes grooves that help reduce molten metal build up between the bearing surface of the impeller or device and the bearing surface of a pump chamber.

Abstract: A structural component for a device for the treatment of melts, especially of glass melts, having a base body of metal or of a metal alloy and a cooling system in which a cooling medium is led through the structural component for the leading-off of heat. The base body is provided with a coating of a material the decomposition temperature of which lies below the temperature of the melt, and the cooling system is designed and arranged in such manner that the temperature of the boundary layer of the melt that immediately surrounds the structural component lies below the decomposition temperature of the coating material.

Abstract: A molten metal pump shaft coupling system for use in the coupling or connection of elongated shafts to other components and equipment, and for the disconnection thereof. A coupling with internal discontinuous threads may be coupled with an externally threaded shaft, with either continuous or discontinuous threads. Aspects of the invention include multiple external threads which may be pitched to accomplish a quicker and more efficient disconnect system. Furthermore, a shaft removal system is provided which provides two points of contact to assist in rotating a broken shaft end out of a coupling.

Abstract: An apparatus for moving a stream of molten metal comprising a pumping member, a housing at least partially enclosing the pumping member, a power device seated on a support, and a shaft connecting the power device and the pumping member. At least one post is disposed between the support and the housing. The post includes an elongated rod comprising a metal alloy surrounded by an outer sheath. An inner member may surround the rod and provide a molten metal resistant barrier. The rod includes a first end connected to the support and a second end secured to the housing. A similar design for a shaft is also provided.

Abstract: A mixer (10) for mixing molten metal in a kettle is disclosed. The mixer (10) broadly includes a housing (12), a drive train assembly (14) supported on the housing (12), and an impeller assembly (16) rotatably coupled to the drive train assembly (14). The drive train assembly (14) broadly includes a power source (18), a rotatable shaft (20), and a transmission (22) drivingly connecting the power source (18) and the shaft (20). The housing (12) is a self-contained unit that supports the mixer (10) and includes an upper housing section (24) that is shiftable relative to a lower housing section (26) between a raised position and a lowered positioned. The transmission (22) includes an endless belt (118) than entrains a fan (122) fixed to the shaft (20). The fan (122) forces a stream of air over bearings (106,108) that support the shaft (20) and over the power source (18) when the shaft (20) is rotated.

Abstract: A device for submerging scrap metal includes: (a) a drive source, (b) a drive shaft having a first end and a second end, the first end being connected to the drive source, and (d) an impeller connected to the second end of the drive shaft, the impeller preferably having two or more outwardly-extending blades. Preferably, each of the blades has a portion that directs molten metal at least partially downward. The impeller design leads to lower operating speeds, lower vibration, longer component life and less maintenance. Additionally, the impeller preferably has a connective portion. The connective portion is used to connect the impeller to the shaft and preferably comprises a nonthreaded, tapered bore extending through the impeller.

Abstract: A mixer (10) for mixing molten metal in a kettle is disclosed. The mixer (10) broadly includes a housing (12), a drive train assembly (14) supported on the housing (12), and an impeller assembly (16) rotatably coupled to the drive train assembly (14). The drive train assembly (14) broadly includes a power source (18), a rotatable shaft (20), and a transmission (22) drivingly connecting the power source (18) and the shaft (20). The housing (12) is a self-contained unit that supports the mixer (10) and includes an upper housing section (24) that is shiftable relative to a lower housing section (26) between a raised position and a lowered positioned. The transmission (22) includes an endless belt (118) than entrains a fan (122) fixed to the shaft (20). The fan (122) forces a stream of air over bearings (106,108) that support the shaft (20) and over the power source (18) when the shaft (20) is rotated.

Abstract: A device for submerging scrap metal includes: (a) a drive source, (b) a drive shaft having a first end and a second end, the first end being connected to the drive source, and (d) an impeller connected to the second end of the drive shaft, the impeller preferably having two or more outwardly-extending blades. Preferably, each of the blades has a portion that directs molten metal at least partially downward. The impeller design leads to lower operating speeds, lower vibration, longer component life and less maintenance. Additionally, the impeller preferably has a connective portion. The connective portion is used to connect the impeller to the shaft and preferably comprises a nonthreaded, tapered bore extending through the impeller.

Abstract: A device for dispersing gas into molten metal includes an impeller and a shaft having a first end and a second end. The second end of the shaft is connected to the impeller and the first end is connected to the drive source that rotates the shaft and impeller. The impeller includes a bottom surface, one or more cavities open to the bottom surface, one or more gas-release openings and a connector. The shaft has a gas-transfer passage therein. A gas source is connected to the first end of the shaft. Gas is transferred through the gas-transfer passage and exits through the gas-release opening(s). At least some of the gas enters the cavities where it is mixed with the molten metal being displaced by the impeller. The configuration of the impeller causes the gas and metal to mix efficiently throughout the molten metal bath. Also disclosed are dual-flow and tri-flow impellers that can be used to practice the invention.

Abstract: Process and device for precipitating solid compounds from zinc metal baths. Partial amounts of the metal phase containing these compounds are exposed to an acceleration higher than gravity and dissociated into fractions containing heavier or lighter components. The molten mass depleted of solid compounds is returned to the metal bath. The device has a hollow rotary body for introduction into the molten mass and provided with a discharge opening for the depleted molten mass and a discharge opening for the liquid metal enriched with the solid compounds.

Abstract: A metal melting closed furnace which includes a main chamber, a circulation well connected to the main chamber by a communications passageway and a vortex well having a exit outlet for molten metal into the main chamber. A cover is emplaced over the vortex well. An inert gas bubble activated molten metal pump is provided in which there is an entry port in the circulation well and exit port into the vortex well. The exit port is positioned to lie at least partially or entirely above the maximum level of molten metal in the vortex well. This exit port will typically be at or near the top of the vortex well. In order to reduce oxidation, inert gas bubbles are captured from this molten metal pump and creating an inert gas atmosphere or blanket above the molten metal vortex.

Abstract: A method for mixing particles in a liquid or semi-liquid medium, such as ceramic reinforcing particles in a molten metal or metal alloy matrix for the production of stir-cast metal matrix composite (MMC) materials. The particles can be introduced under the surface of the matrix by feeding the particles through the inner passage of a rotatable hollow impeller tube. The impeller tube is terminated at its lower end by an impeller head that includes teeth positioned proximate to an impeller base. The particles enter the matrix through a shear region in and around the volume between the impeller base and the impeller head. The rotating impeller and the high shear force thereby created wet the particles in the composite matrix and effect homogenization of the composite matrix. The present invention may be practiced either under vacuum or atmospheric pressure.

Abstract: A shaft for use with molten aluminum using an impeller mounted on the shaft comprising a protective refractory sleeve resistant to attack by molten aluminum, the protective sleeve employing a reinforcing media and mounted on the shaft to extend above and below the molten aluminum surface when the shaft is in use.

Abstract: A dosing furnace (10) with metal treatment and level control includes a holding chamber (12) for containing a supply of molten metal (50), a pump (22) connected to the holding chamber (12), a molten metal treatment chamber (16, 18) located at an outlet (26) of the pump (22), and a dosing chamber (40) located downstream and in fluid communication with the molten metal treatment chamber (16, 18). A molten metal level sensor (56) is located in the dosing chamber (40). The pump (22) is a variable speed pump having a pump inlet (24) connected to the holding chamber (12) and configured to pump the molten metal (50) through the dosing furnace (10) during operation. The molten metal level sensor (56) is connected to the pump (22) for providing a pump speed control signal to the pump (22).

Abstract: A molten metal treatment furnace (10) with metal treatment and level control includes a heating chamber (12) for containing and heating a supply of molten metal (60), a pump (22) connected to the heating chamber (12), a molten metal treatment chamber (16, 18) located at the outlet of the pump (22), and a dosing chamber (40) located downstream and in fluid communication with the molten metal treatment chamber (16, 18). A trough (44) is connected to the dosing chamber (40) for supplying the molten metal (60) to a downstream process. A molten metal level sensor (66) is located in the dosing chamber (40). The pump (22) is a variable speed pump having a pump inlet (24) connected to the heating chamber (12) and configured to pump the molten metal (60) through the furnace (10) during operation. The molten metal level sensor (66) is connected to the pump (22) for providing a pump speed control signal to the pump (22).

Abstract: An apparatus for mixing particles in a liquid or semi-liquid medium, such as ceramic reinforcing particles in a molten metal or metal alloy matrix for the production of stir-cast metal matrix composite (MMC) materials. The particles can be introduced under the surface of the matrix by feeding the particles through the inner passage of a rotatable hollow impeller tube. The impeller tube is terminated at its lower end by an impeller head that includes teeth positioned proximate to an impeller base. The particles enter the matrix through a shear region in and around the volume between the impeller base and the impeller head. The rotating impeller and the high shear force thereby created wet the particles in the composite matrix and effect homogenization of the composite matrix. The present invention may be practiced either under vacuum or atmospheric pressure.

Abstract: Soft solder powder is made in the form of spherical fine metal particles having a grain size ranging from 1 to 100 &mgr;m and a Liquidus temperature <250° C.