Abstract: Disclosed is a rare earth magnet in the R-T-B (rare earth element-transition metal-boron) system that is made from an improved composition and properties of main phase alloy in the R-T-B system containing Pr and a boundary alloy. Disclosed also is a manufacturing method of the rare earth magnet alloy flake by a strip casting method with improved rotating rollers such that the alloy flake has a specified fine surface roughness and has a small and regulated amount of fine R-rich phase regions. Consequently, the alloy flake for the rare earth magnet does not containing ?-Fe and has a homogeneous morphology so that the rare earth magnet formed by sintering or bonding the alloy flakes exhibits excellent magnetic properties.

Abstract: A method for producing an outer layer for a roll having a structure having MC carbide dispersed at an area ratio of 20-60%, comprising the steps of (1) centrifugally casting a melt having a composition comprising, by mass, 2.2-6.0% of C, 0.1-3.5% of Si, 0.1-3.5% of Mn, and 8-22% of V, the balance being Fe and inevitable impurity elements, to produce a cylindrical body comprising an inner layer having concentration MC carbide, an MC-carbide-poor outer layer, and a concentration gradient layer between the inner layer and the outer layer, in which the area ratio of MC carbide changes, and (2) cutting the cylindrical body to a depth at which the area ratio of MC carbide is 20% or more.

Abstract: The invention makes it possible to manufacture high-quality cast parts in a productive manner in that a casting mould with a filling opening pointing in the direction of gravity is provided during the casting of molten metal. The casting mould with the filling opening is coupled to a melt container containing the molten metal, and the molten metal is conveyed from the melt container into the casting mould counter to the direction of gravity. The casting mould is sealed directly after filling with molten metal using a locking means which is at least temporarily connected to the casting mould in a fixed manner, in that the casting mould is decoupled from the melt container directly after closure of the casting mould and in that the casting mould is rotated about a horizontal axis of rotation, wherein the casting mould remains in a sealed position with respect to the locking means.

Abstract: Techniques for forming cast parts for medical devices suitable for contact with internal regions of patients are described herein. Such parts can be small in scale (e.g., having a major axis less than 0.3 inches, and/or a minor axis less than about 0.08 inches), and can be formed from metals that have a high melting point and high reactivity with environmental components or mold surfaces, such as stainless steel and titanium alloys. Such techniques can include injecting molten metal into the sprue of a mold tree such that the side runners are backfilled after the molten metal impacts a closed end of the sprue. Side runners can be oriented in particular directions and positions to promote backfilling. As well, flask temperatures and the use of surfactants can also promote cast part formation, hindering the formation of surface defects.

Abstract: A tubular formation technique utilizing centrifugal casting incorporating a moveable launder system to deliver molten alloy along an extended length within a centrifugal caster to form a hollow tubular precursor of extended length. The technique is adaptable to all alloy systems but may be particularly suited for so called “hard alloys” that are susceptible to substantial work hardening or are difficult to extrude.

Abstract: Herein disclosed is a centrifugally cast pole having a substantially uniform wall thickness along the long axis of the pole. During centrifugal casting, molten metal is poured inside a rotating, tapered mold. As chilled liquid is poured over the outside of the rotating mold, the metal forms, or paints, to the contour of the mold interior creating a metal pole. By precisely controlling casting gyrations such as the spin, travel, pitch, and yaw of the rotating mold and the calibration and physical mechanisms of the casting machine, hollow, tapered, tubular metal poles are produced with previously unknown uniformity of wall thickness. The controlling principles, designs, and mechanisms of this centrifugal casting method enable wall uniformity to extremely high tolerances. By extension, the ability to precisely control the metal volume painted inside the mold allows, as a design choice, wall thickness variation in any embodiment if so desired.

Abstract: Techniques for forming cast parts for medical devices suitable for contact with internal regions of patients are described herein. Such parts can be small in scale (e.g., having a major axis less than 0.3 inches, and/or a minor axis less than about 0.08 inches), and can be formed from metals that have a high melting point and high reactivity with environmental components or mold surfaces, such as stainless steel and titanium alloys. Such techniques can include injecting molten metal into the sprue of a mold tree such that the side runners are backfilled after the molten metal impacts a closed end of the sprue. Side runners can be oriented in particular directions and positions to promote backfilling. As well, flask temperatures and the use of surfactants can also promote cast part formation, hindering the formation of surface defects.

Abstract: A plasticizing barrel for a plastics processing machine includes a body having a hollow cylindrical configuration and defining an axis; and a coating formed on an inner wall surface of the body and including at least one groove extending in axial direction of the body. The coating, e.g., a wear-resisting protective layer, may be produced through centrifugal casting, whereby the grooves are formed by projections of a negative mold inserted in the hollow-cylindrical body.

Abstract: Molds are fabricated having a substrate of high density, high strength ultrafine grained isotropic graphite, and having a mold cavity coated with a refractory metal such as W or Re or a refractory metal carbide such as TaC or HfC. The molds may be made by making the substrate (main body) of high density, high strength ultrafine grained isotropic graphite, by, for example, isostatic or vibrational molding, machining the substrate to form the mold cavity, and coating the mold cavity with titanium carbide via either chemical deposition or plasma assisted chemical vapor deposition, magnetron sputtering or sputtering. The molds may be used to make various metallic alloys such as nickel, cobalt and iron based superalloys, stainless steel alloys, titanium alloys and titanium aluminide alloys into engineering components by melting the alloys in a vacuum or under a low partial pressure of inert gas and subsequently casting the melt in the graphite molds under vacuum or low partial pressure of inert gas.

Abstract: A system and method for centrifugal casting of composites, especially metal-matrix composites. According to the system and method, a porous preform is infiltrated with matrix material using a centrifugal force to pressurize the matrix material against the preform. The pressure head of the matrix material is maintained at an approximately constant level throughout infiltration.

Abstract: A method and apparatus for centrifugal casting of metal articles uses a rotating mold body that can be pivoted from a vertical orientation to a horizontal orientation during the centrifugal casting of the metal article. The resulting metal article has a closed end and an open end defining a hollow cavity. The mold body has a closed end that is oriented in a vertical position with the longitudinal axis extending vertically. While the mold body is rotated, an amount of molten metal is introduced into the mold body so that the molten metal is distributed along the closed end of the mold body. In one embodiment, the bottom end of the mold body has a frustoconical shaped surface defining the mold cavity. The mold body is then pivoted to a horizontal position while continuously rotating to distribute and cast the metal against the inner surface of the mold body. In one embodiment, the mold body has a refractory lining of a compacted refractory material.

Abstract: A centrifugal casting method is provided for the manufacture of hollow molds and applications of this apparatus and method are provided. A centrifugal casting apparatus has a hollow mold (13) suitable for the centrifugal casting. For the manufacture of cast workpieees by the centrifugal casting method a plurality of mold cavities (14) formed by at least one hollow mold (13) are arranged and driven such that the mold cavities (14) rotate about a common axis of rotation (18). At least three mold cavities (14) which rotate in a single plane are provided.

Abstract: The present invention relates to a casting method which employs rapid solidification of metal, rare-earth metal or the like, as well as to a casting apparatus and a cast alloy. A centrifugal casting method includes the steps of pouring a molten material onto a rotary body; sprinkling the molten material by the effect of rotation of the rotary body; and causing the sprinkled molten material to be deposited and to solidify on the inner surface of a rotating cylindrical mold. The axis of rotation of the rotary body and the axis of rotation of the cylindrical mold are caused not to run parallel to each other. The centrifugal casting method can attain a decrease in average deposition rate. As a result, generation of the dendritic &agr;Fe phase or generation of a segregation phase of Mn or the like is suppressed, thereby realizing a high-performance R-T-B-type rare-earth magnet alloy.

Abstract: A system and method for centrifugal casting of composites, especially metal-matrix composites. According to the system and method, a porous preform is infiltrated with matrix material using a centrifugal force to pressurize the matrix material against the preform. The pressure head of the matrix material is maintained at an approximately constant level throughout infiltration.

Abstract: To produce precision castings from a melt, use is made of a metallic casting wheel (1) which has an annular distribution channel (4) and a plurality of interchangeable casting moulds (6), each having at least one filling opening (6a). The melt quantity per casting operation is chosen here such that the casting moulds (6) and the distribution channel (4) are filled with the melt upon the rotation of the casting wheel (1) about its axis (A—A), in such a way that after the solidification of the melt the precision castings are held together by a ring of the casting material which is formed in the distribution channel (4), the so-called circulating material for new casting processes, and are removed from the casting wheel (1) together with the casting moulds (6), whereupon the precision castings are separated from the ring.

Abstract: Methods for making various titanium base alloys and titanium aluminides into engineering components such as rings, tubes and pipes by melting of the alloys in a vacuum or under a low partial pressure of inert gas and subsequent centrifugal casting of the melt in the graphite molds rotating along its own axis under vacuum or low partial pressure of inert gas are provided, the molds having been fabricated by machining high density, high strength ultrafine grained isotropic graphite, wherein the graphite has been made by isostatic pressing or vibrational molding, the said molds either revolving around its own horizontal or vertical axis or centrifuging around a vertical axis of rotation.

Abstract: Methods for making various titanium base alloys and titanium aluminides into engineering components such as rings, tubes and pipes by melting of the alloys in a vacuum or under a low partial pressure of inert gas and subsequent centrifugal casting of the melt in the graphite molds rotating along its own axis under vacuum or low partial pressure of inert gas are provided, the molds having been fabricated by machining high density, high strength ultrafine grained isotropic graphite, wherein the graphite has been made by isostatic pressing or vibrational molding, the said molds either revolving around its own horizontal or vertical axis or centrifuging around a vertical axis of rotation.

Abstract: The invention relates to a centrifugal casting method, a centrifugal casting apparatus, a hollow mold (13) suitable for the centrifugal casting, a runner bush molder suitable for the manufacture of such hollow molds and applications of this apparatus and method. For the manufacture of cast workpieces by the centrifugal casting method a plurality of mold cavities (14) formed by at least one hollow mold (13) are arranged and driven such that the mold cavities (14) rotate about a common axis of rotation (18) At least three mold cavities (14) which rotate in a single plane are provided.

Abstract: Methods for making various nickel based superalloys into engineering components such as rings, tubes and pipes by melting of the alloys in a vacuum or under a low partial pressure of inert gas and subsequent centrifugal casting of the melt in the graphite molds rotating along its own axis under vacuum or low partial pressure of inert gas are provided. The molds have been fabricated by machining high density, high strength ultrafine grained isotropic graphite, wherein the graphite has been made by isostatic pressing or vibrational molding.

Abstract: A method and apparatus for use in centrifugal casting of metal articles forms a compacted lining of a particulate refractory material on an inner surface of the mold. An amount of a dry binderless particulate refractory material is dispensed on the inner surface of a rotating mold body to form a centrifugally densified layer. A plowing tool is brought into contact with a layer of refractory material while continuously rotating the mold body to plow and compact the layer of particles. The tool is oriented at an angle with respect to the direction of travel of the layer of particles to penetrate the layer and compact the particles toward the inner surface of the mold body. The combination of the centrifugal force and the mechanical compaction of the particles results in a dense, air impervious, compacted mold lining having interlocked particles and voids between the particles that are not interconnected with an adjacent void.

Abstract: Method and apparatus for countergravity casting a plurality of articles wherein a ceramic mold is provided having an upstanding riser passage and a plurality of mold cavities disposed along a length of the riser passage at different elevations, each mold cavity communicating to the riser passage via a gate passage, wherein molten metal is forced to flow upwardly from a source into the riser passage for supply to the mold cavities via their gate passages, wherein the mold is rotated so that molten metal that resides in the gate passages is subjected to centrifugal force in a direction toward the mold cavities, and wherein molten metal in the riser passage is drained to empty the riser passage before molten metal in the mold cavities and the gate passages solidifies, leaving the gate passages at least partially filled with molten metal for supply to the mold cavities in response to shrinkage as molten metal therein solidifies while the container is rotated.

Abstract: To produce precision castings from a melt, use is made of a metallic casting wheel (1) which has an annular distribution channel (4) and a plurality of interchangeable casting moulds (6), each having at least one filling opening (6a). The melt quantity per casting operation is chosen here such that the casting moulds (6) and the distribution channel (4) are filled with the melt upon the rotation of the casting wheel (1) about its axis (A-A), in such a way that after the solidification of the melt the precision castings are held together by a ring of the casting material which is formed in the distribution channel (4), the so-called circulating material for new casting processes, and are removed from the casting wheel (1) together with the casting moulds (6), whereupon the precision castings are separated from the ring.

Abstract: A method and apparatus for use in centrifugal casting of metal articles forms a compacted lining of a particulate refractory material on an inner surface of the mold. An amount of a dry binderless particulate refractory material is dispensed on the inner surface of a rotating mold body to form a centrifugally densified layer. A plowing tool is brought into contact with a layer of refractory material while continuously rotating the mold body to plow and compact the layer of particles. The tool is oriented at an angle with respect to the direction of travel of the layer of particles to penetrate the layer and compact the particles toward the inner surface of the mold body. The combination of the centrifugal force and the mechanical compaction of the particles results in a dense, air impervious, compacted mold lining having interlocked particles and voids between the particles that are not interconnected with an adjacent void.

Abstract: An inventive cylinder liner of the present invention includes a dual phase graphite morphology. An outer diameter of the cylinder liner is comprised of ductile (nodular) and vermicular iron while an inner diameter of the cylinder liner is comprised of predominantly gray iron. A transition region of predominantly vermicular iron is preferably disposed between the inner diameter and the outer diameter. The inventive cylinder is preferably made using a centrifugal casting process, which provides a transition in the cylinder wall between the ductile and vermicular iron at the outer diameter to the predominantly gray iron at the inner diameter.

Abstract: A bent pipe for use in piping arrangement for transporting materials conaining solids, the bent pipe being prepared by subjecting to high-frequency bending work a straight blank pipe prepared by centrifugal casting and having a plurality of layers. The straight blank pipe comprises an outer layer made of a steel having high weldability, and an inner layer made of a high Cr cast iron containing at least Cr in an amount of 10 to 35 wt. % and having high wear resistance, the outer layer and the inner layer being metallurgically joined. Preferably, a barrier layer is provided between the outer layer and the inner layer for preventing an alloy component in each of the layers from diffusing into the other layer. The barrier layer is preferably about 10 to about 100 &mgr;m in thickness.

Abstract: While rotating a chamber 10 with a crucible 18 for heating ingots 28 of metal and a mold 23 for receiving molten metal from the crucible 18 enclosed therein from a normal position to a reversed position, when an arrival of the chamber 10 at a preset reference position is detected by a rotary plate 36 and a position sensor 37, a pressure gas is introduced into the chamber 10 at a time point delayed from the reference position by a preset delay time. The delay time is preset so that the pressurize gas starts pressing the molten metal into a sprue runner 26 immediately after a mouth of the sprue runner 26 is completely closed by the molten metal poured from the crucible 18. Thus, the molten metal is promptly pressed through the sprue runner 26 into a cavity 27 of the mold 23 before it starts solidifying due to the contact with the mold 23 having a temperature lower than that of the molten metal.

Abstract: A method through which we can synthesize Functionally Graded Materials (FGM). Such materials are made so that their composition changes gradually from one point to another, such as in the example of gradient index (GRIN) optical components. A novel aspect of our method is the imposition of a centrifugal force during the combustion synthesis of composite materials for structural, optical, or electronic applications, with the result that the composition and the particle size of the metallic (or ceramic) component changes continuously and across the thickness of the product. We have prepared such FGM as ZrO.sub.2 +Ni, ZrO.sub.2 +Cu and Al.sub.2 O.sub.3 +Cu.

Abstract: Alumina tiles within aluminum framing jigs are fixedly positioned by lock ns within an internally coated mold for centrifugal casting within a block of an aluminum alloy material. Such jigs and the tiles framed therein are coated with silver before casting to prevent aluminum oxidation by heating of the aluminum material to a molten state for deposit into the mold. Bonding of the tiles and framing of the jigs with the aluminum material being cast is also enhanced by such silver coating.

Abstract: The article is produced by prepositioning nonwoven reinforcement, coated h a bond enhancing compound inside of a centrifugal casting mold that is surface coated for protective shielding of the reinforcement. Molten matrix metal is then introduced into the mold while being rotated about its longitudinal axis until the molten metal completely encapsulates the reinforcement.

Abstract: For the production of particles from castings (10) of metals from the group of the lanthanides, aluminum, boron, chromium, iron, calcium, magnesium, manganese, nickel, niobium, cobalt, titanium, vanadium, zirconium, and their alloys, which have solidified in an oriented manner, especially for the production of materials from the group of magnetic materials, hydrogen storage elements (hydride storage elements), and battery electrodes, a melt of the metal is applied in a nonreactive atmosphere to the inside of an at least essentially cylindrical cooling surface (9) according to the principle of centrifugal casting. The cylinder rotates at high speed around a rotational axis, and the melt is cooled proceeding from the outside toward the inside with an essentially radial direction of solidification. The hollow casting (10) is then reduced to particles.

Abstract: The method comprises the step of arranging at the periphery of a shell (10) capable of withstanding a temperature of at least 400.degree. C. inserts (16) of highly wear-resistant material, preheating the shell (10) and the inserts (16) in an oven, removing rapidly the shell (10) together with the inserts (16) from the oven, placing them on a centrifugal casting machine which is set in rotation, pouring ductile cast iron (18) and demoulding after cooling.

Abstract: The segregation in the hydrogen-absorbing alloy is decreased by a centrifugal casting which is devised in the present invention so that: a melt fed to the bottom portion of a cylindrical rotary mold solidifies during one rotation of the mold; and, the average depositing speed of melt is from approximately 0.005 to 0.1 cm/second.

Abstract: In the production of castings from a melt of a reactive metal selected from the group consisting of titanium, titanium alloys, and titanium-based alloys, a reusable casting mold (20) is used; the mold, at least in the area of the surface which comes in contact with the melt, consists of at least one metal selected from the group consisting of tantalum, niobium, zirconium, and/or their alloys. The casting mold (20) preferably consists, at least in the area of the surface which comes in contact with the melt, of a tantalum based alloy containing at least 50 wt. % of tantalum. The casting molds can be made of a homogeneous metal, but it is also possible to insert shells of the metals in question into a base body to form the boundaries of the mold cavities, whereas the base body itself consists of some other metal or alloy or of a nonmetal such as graphite or silicon nitride.

Abstract: A one-piece steering wheel is formed as a unitary casting from an alloy that includes 11.5% to 14% by weight silicon, and 350 to 450 parts per million strontium. Preferably the steering wheel mold is rotated during casting at relatively high rotational speeds exerting 100 g to 250 g force on the wheel. An optimum rotational speed is disclosed. A one-piece steering wheel formed according to the invention exhibits minimal length ferro-silicon hair-like strands, and thus exhibits reduced brittleness.

Abstract: A process for casting a hard-faced cylindrical product such as an automobile camshaft includes the steps of: (a) preparing a composition formed from a molten base metal and an additive in particle form and having a hardness value greater than the hardness value of the base metal; (b) introducing the composition into a flask containing a meltable pattern of a cylindrical product such as an automobile camshaft to be manufactured and encased in sand to allow the composition to melt the pattern and assume the shape of the pattern within the sand; and (c) rotating the flask containing the pattern about the longitudinal axes of both the flask and the pattern as the molten base metal containing the additive in particle form is introduced into the flask to cause particles of the additive entrained in the molten base metal to migrate by centrifugal action to the radial extremities of the pattern and thereby provide a cylindrical product having a hardness value greater at it's radial extremities than at its center when

Abstract: A method is provided for producing by centrifugal casting an alloy tubular article of manufacture in the form of a composite tubular product comprised of an outer alloy layer (first alloy) and at least one inner alloy layer (second alloy) while substantially inhibiting the formation of a metallurgical bond between layers in the final casting. The product is produced using a rotatable centrifugal casting mold having a cylindrical inner surface adapted to receive a molten metal alloy. A first layer of an alloy is poured into the rotatable mold, the alloy having a melting point of at least about 1300.degree. C. and generally at least about 1400.degree. C. Centrifugally casting said alloy as an outer layer during rotation of said mold. The outer layer is solidified and cooled to a temperature not exceeding about 92% of its absolute melting point in degrees Kelvin. At least one inner layer is poured into the outer layer, the alloy of the inner having a melting point of at least about 1300.degree. C.

Abstract: A vacuum centrifugally cast combustion liner suitable for use in a gas turbine engine operating at temperatures ranging from ambient up to about 1700.degree. F. is provided. The combustion liner is formed by centrifugally vacuum casting a precipitation hardened nickel-based superalloy having controlled, low amounts of aluminum and titanium. The combustion liner is characterized by a homogeneous grain structure having enhanced strength and creep resistance particularly at elevated temperatures. In addition, the preferred elemental composition, particularly the relatively small amounts of aluminum and titanium, enhance the weldability and overall manufacturability of the combustion liner.

Abstract: The compound roll having a shell portion made of a hard, high-alloy cast steel or iron having excellent wear resistance and resistance to surface roughening and a core portion made of a tough cast iron or cast steel, the cast iron of the shell portion having a composition consisting essentially, by weight ratio, of 1.0-3.0% of C, 2.0% or less of Si, 2.0% or less of Mn, 2.0-15.0% of Cr, 10.0% or less of Mo, 2.0-8.0% of V, the balance being substantially Fe and inevitable impurities, an average diameter of crystal grains constituting a matrix of the metal structure of the shell portion being 100 .mu.m or less in a range from a surface to a depth of 50 mm when determined by an image analysis method on the crystal grains having diameters exceeding 30 .mu.m, and the crystal grains satisfying the formula: m.sub.2 .ltoreq.1.2 m.sub.1, wherein m.sub.1 is an average diameter of the crystal grains at the surface of the shell portion, and m.sub.

Abstract: A centrifugal casting carrier system comprising a fixed roller conveyor, a pivotal roller conveyor provided at an adjustable angle to the fixed roller conveyor to form a V-shaped path and thrust arms provided at an approximately right angle to the pivotal roller conveyor for thrusting castings out of the V-shaped path when opened. In operation, a casting from one of the casting molds is drawn onto the V-shaped path. When the pivotal roller conveyor is lowered to open the V-shape path, the thrust arms are raised thrusting the casting out of the V-shaped path onto a stocker. By repeating the operation, multiple castings can be continually drawn and carried away to the stocker without delay.

Abstract: The article is produced by prepositioning nonwoven reinforcement made of a etallic mesh to which ceramic tiles are wired inside of a centrifugal casting mold. Molten matrix metal is then introduced into the mold while being rotated about an axis parallel to the inflow path of the molten metal until it completely encapsulates the reinforcement.

Abstract: A casting is produced by centrifugal casting in which molten metal of gray cast iron is poured into a cavity formed in a mold during rotation of the mold under centrifugal force. The casting comprises a gray cast iron region and a spheroidal graphite cast iron region from which the graphite structure is gradually transformed toward the gray cast iron region through an intermediate region of vermicular graphite. The spheroidal graphite region and the intermediate region are formed by a reaction of the molten metal with spheroidizing agent in the cavity during rotation of the mold and solidification of the molten metal. The spheroidizing agent is provided in the cavity to a position where the casting is to be increased in strength and abrasion resistance. The spheroidizing agent can be introduced along with the molten metal through the pouring gate into the mold cavity to a defined position of casting.

Abstract: Cast vehicle wheels are formed with a re-entrant portion or lightening pocket beneath the tire bead retaining seat. The mold has movable side portions enabling the formation of the re-entrant portion in the wheel. The re-entrant portion reduces the weight of the wheel without adversely affecting the wheel characteristics.

Abstract: A hypereutectic aluminum-silicon alloy cylinder bore liner is produced by feeding the molten alloy into a metal mold having an inner shell sand cup, while rotating the mold at a speed in excess of 1,000 rpm, to cause the molten alloy to be thrown outwardly by centrifugal force to form a cylindrical liner. On solidification of the alloy, discrete silicon particles are precipitated and the use of the sand shell increases the fluid life of the alloy to enable the lighter weight silicon particles to migrate inwardly under the centrifugal force of rotation, to produce a solidified liner having a greater volume fraction of silicon particles in the inner portion of the liner where greater wear resistance is desired.

Abstract: A reinforcement made of a composite material is positioned inside of a ceifugal casting mold. Molten matrix metal is then introduced into the mold while being rotated about its longitudinal axis until the molten metal completely encapsulates the reinforcement.

Abstract: The present invention relates to alloys having substantially uniform aggregate distribution, a method of making such alloys, and centrifugally cast members made from such alloys. The alloys of the present invention utilize aggregates of tungsten carbide, vanadium carbide and titanium carbide so formulated to allow them to be uniformly distributed throughout the alloy matrix.

Abstract: A method of casting metal matrix composites wherein there is a wide disparity in the respective densities of the metal matrix and the reinforcing particles. The particles are added to a melt of molten metal and the mixture is stirred using an impeller rotating at a high speed so as to ensure an even distribution of the less dense reinforcing particles throughout the denser metal matrix.

Abstract: An apparatus for centrifugal casting of hollow articles in particular pipes. The apparatus has an elongate generally cylindrical hollow mould with a center conductor extending along the longitudinal axis so that the combination acts as a coaxial waveguide. A microwave source and waveguide system are provided to direct substantially TEM mode radiation into one end of the mould. The mould and center conductor are terminated at the other end by a short circuit to microwave radiation so that standing waves are established in the mould. The invention also provides a method for centrifugal casting of such articles in which a casting composition is placed in a hollow rotating mould and microwave radiation is directed into the mould to heat the casting composition.

Abstract: A process for the centrifugal casting of copper, copper alloys, or other oxygen sensitive alloys, such as bronze, is effective for avoiding or reducing the formation of an oxide layer on the inner surface of the casting. The process essentially consists of applying powdered borax in a layer thickness of 0.5 mm to 4 mm onto the still liquid inner surface of the casting immediately after pouring the casting. The preferred thickness of the borax is 1 mm to 3 mm. Finely divided mixtures of metals which have an affinity for oxygen, such Mg, Li, Ce, and/or powders of graphite and/or fire clay and/or charcoal, can also be combined with the borax as additional additives for special casting processes. Apparatus for introducing the borax into the mold includes a trough which is extendable into the interior of the mold. The trough is either rotatably supported in a housing that is movable relative to the mold, or pivotally supported along a bottom portion of a pouring tube which is movable relative to the mold.

Abstract: A centrifugal vacuum assist ambient air casting apparatus and method to fill a casting flask having a mold with a pour opening in communication with the pour opening of a casting crucible filled with molten metal and ceramics comprising: centrifugally spinning the casting flask and casting crucible with their pour openings aligned such that the resulting centrifugal forces empty the contents of the casting crucible into the casting flask, while simultaneously applying a directional vacuum to the casting flask in alignment with the resultant centrifugal forces to evacuate trapped gases from the mold and assist in drawing in the molten metal and ceramics into the mold.

Abstract: In a Cu-alloy mold for use in centrifugal casting of Ti or Ti-alloys, the mold body is made of a Cu alloy satisfying the following relationship:Ts+0.3.rho..gtoreq.70where Ts is the tensile strength (kg/mm.sup.2), and .rho. is the electrical conductance (% IACS). A cavity disposed in the mold body has a volume which is at most 30% of the volume of the mold body. Also disclosed is a method for centrifugally casting Ti or Ti-alloy by the use of the above-described mold.