Abstract: An object of the present invention is to provide a method of producing an Ag—ZnO electric contact material which can uniformly disperse ZnO micrograms in Ag; which maintains low contact resistance; which exhibits enhanced welding resistance and wear resistance; and which is suitable in view of production costs. The method of producing an Ag—ZnO electrical contact material comprises casting Ag and Zn at predetermined proportions and subjecting the resultant Ag—ZnO alloy to internal oxidation so as to disperse ZnO in Ag, the method being characterized in that an Ag—Zn alloy comprising 5-10 wt. % (as reduced to weight of metal) Zn, the balance being Ag, is formed into chips; the chips are subjected to internal oxidation; the internally oxidized chips are compacted to thereby form billets; the billets are pressed and sintered; and subsequently, the sintered billets are extruded, to thereby yield uniform dispersion, in Ag, of ZnO micrograms.

Abstract: Disclosed is a method for manufacturing a billet using aqueous salt solutions. The method for manufacturing a billet using aqueous salt solutions, comprising the following steps of: infiltrating aqueous salt solutions into metal powders or cut metal wires by adding the solutions to metal powders or cut metal wires filled in a cylindrical container, to obtain a mixture of aqueous salt solutions infiltrated into the metal powders or metal wires; evaporating water in aqueous salt solutions by heating said container containing the mixture, to obtain a dried mixture; and separating said dried mixture of metal powders or metal wires and salts from the container, to obtain a billet.

Abstract: This invention concerns a lubricant for warm compaction of iron-based metallurgical powder compositions. 50 to 100% by weight of the lubricant is a polyester, aromatic or partly aromatic, which has a number-average molecular weight Mn of 5,000-50,000. This invention further concerns a metal powder composition containing the lubricant, a method for making sintered products by using the lubricant, and use of the same in warm compaction of metallurgical powders.

Abstract: The present invention concerns a process of preparing high density, warm compacted bodies of a stainless steel powder comprising the steps of providing a mixture of a low carbon, low oxygen stainless steel powder including 10-30% by weight of Cr, optional alloying elements and graphite and inevitable impurities, mixing the powder with a high temperature lubricant and compacting the mixture at an elevated temperature. The invention also concerns a composition of the stainless steel powder, optional additional alloying elements and a high temperature lubricant.

Abstract: An iron-graphite composite powder having a microstructure comprising carbon clusters embedded in a ferrous matrix is disclosed. Also disclosed is a process for preparing the iron-graphite composite powder, a process for preparing sintered articles from this composite powder and the sintered articles prepared thereby.

Abstract: A method of manufacturing a sintered anode unit for a solid electrolytic capacitor is provided. According to this method, a press-molded or compacted pellet of a valve-action metal powder is sintered at a predetermined high temperature and in a predetermined primary vacuum. The pellet is naturally cooled in this primary vacuum, and is cooled by force cooling in an inert gas atmosphere. Thereafter, the sintered pellet is subjected to a repeated cycle processing of vacuum, atmospheric leakage, and vacuum in a gradual-oxidizing chamber. The atmospheric leakage level is increased step by step to set the vacuum level in the gradual-oxidizing chamber to the atmospheric pressure. Then, the sintered pellet having the restricted content of oxygen is taken out from the gradual-oxidizing chamber into the atmosphere.

Abstract: The present invention concerns a method of preparing a sintered product having a tensile strength 750 MPa comprising the steps of compacting a water-atomised, annealed iron-based powder comprising, by weight %, Cr 2.5-3.5, Mo 0.3-0.7, Mn 0.09-0.3, O <0.2, C<0.01 the balance being iron and, an amount of not more than 1%, inevitable impurities, at a pressure of at least 600 MPa and subjecting the compacted body to sintering at a temperature of at most 1220° C. The invention also concerns the annealed powder used in the method as well as the sintered products.

Abstract: A nitrogen containing niobium powder is disclosed as well as electrolytic capacitors formed from the niobium powders. Methods to reduce DC leakage in a niobium anode are also disclosed.

Abstract: A refractory metal silicide target is characterized by comprising a fine mixed structure composed of MSi2 (where M: refractory metal) grains and Si grains, wherein the number of MSi2 grains independently existing in a cross section of 0.01 mm2 of the mixed structure is not greater than 15, the MSi2 grains have an average grain size not greater than 10 &mgr;m, whereas free Si grains existing in gaps of the MSi2 grains have a maximum grain size not greater than 20 &mgr;m. The target has a high density, high purity fine mixed structure with a uniform composition and contains a small amount of impurities such as oxygen etc. The employment of the target can reduce particles produced in sputtering, the change of a film resistance in a wafer and the impurities in a film and improve yield and reliability when semiconductors are manufactured.

Abstract: A metallic alloy composition is manufactured into products such as press formed or stamped products or rolled products such as sheet, strip, rod, wire or band by one or more cold working steps with intermediate or final flash annealing. The method can include cold rolling an iron, nickel or titanium aluminide alloy and annealing the cold worked product in a furnace by infrared heating. The flash annealing is preferably carried out by rapidly heating the cold worked product to an elevated temperature for less than one minute. The flash annealing is effective to reduce surface hardness of the cold worked product sufficiently to allow further cold working. The product to be cold worked can be prepared by casting the alloy or by a powder metallurgical technique such as tape casting a mixture of metal powder and a binder, roll compacting a mixture of the powder and a binder or plasma spraying the powder onto a substrate.

Abstract: A silicon carbide based composite material includes as a first component, a metal mainly consisting of aluminum or copper, and as a second component, particles mainly consisting of silicon carbide having high purity and few defects. The material is obtained by heating a compact of the raw material powder containing the first and second components at a temperature not lower than the melting point of the metal mainly consisting of aluminum or copper, and by forging and solidifying under pressure. Preferably, the silicon carbide raw material powder is prepared to have high purity by carrying out a preliminary treatment, or the material after forging or a material obtained through a conventional infiltration process is further heated at a temperature lower than the melting point of the first component. In this manner, an improved superior thermal conductivity can be obtained.

Abstract: Improved methods for coating particulate materials at low shear conditions and preferably below the melting point of the coating material are provided. In one aspect, metallurgical compositions are provided that contain a metal-based powder bound to an alloying powder or powders by way of a low melting polymer or wax binding agent, which is preferably polyethylene. The binding agent is blended with the metal-based and alloying powders at elevated temperatures preferably below the melting point of the binding agent. The bonded metallurgical composition can be used in compaction processes to manufacture compacted parts that can be sintered to impart strength.

Abstract: A powder metallurgy product which is made from constituent including iron powder. The iron powder includes iron grains which contain machinability improving element in the iron grains. The machinability improving element is configured to improve machinability of the powder metallurgy product and has a pinning effect. An amount (Q) of the machinability improving element is adjusted such that an absolute value of a differential coefficient (dS/dQ) is at least a predetermined value, where (S) is a grain size of iron in the powder metallurgy product.

Abstract: The present invention provides a method, which infiltrates super-heated material between preheated powder particles and therefore minimizes heat deformation and increases measurement accuracy. A rapid prototyping apparatus in accordance with the present invention comprises powder material spreading means 10, dispensing infiltration material means 20, laser beam scanning means 30, and control means. The powder material spreading means spread out powders 61 on the surface of platform 52 uniformly while moving along the X axis. The powders are the main material of desired products. The dispensing infiltration material means dispense infiltration materials 63 while moving along three axes and the super-heated infiltration materials 64 by laser beam 43 are infiltrated between the powders selectively. The laser beam scanning means preheat the powders by laser beam 42 within the melting point of the powders and super-heat the infiltration material by laser beam 43.

Abstract: A method of producing a silicon aluminum sputtering target is provided. The target is formed from a powder base of between about 80% to about 95% by weight silicon and about 5% to about 20% by weight aluminum which is placed in a containment unit, heated under vacuum and then sealed. The base is then subjected to a pressure greater than about 3000 psi and heated to a temperature between about 1076° F. and about 1652° F. such that some, but not more than 30%, of the resulting target is formed from liquid phase silicon-aluminum.

Abstract: A metallic alloy composition is manufactured into products such as press formed or stamped products or rolled products such as sheet, strip, rod, wire or band by one or more cold working steps with intermediate or final flash annealing. The method can include cold rolling an iron, nickel or titanium aluminide alloy and annealing the cold worked product in a furnace by infrared heating. The flash annealing is preferably carried out by rapidly heating the cold worked product to an elevated temperature for less than one minute. The flash annealing is effective to reduce surface hardness of the cold worked product sufficiently to allow further cold working. The product to be cold worked can be prepared by casting the alloy or by a powder metallurgical technique such as tape casting a mixture of metal powder and a binder, roll compacting a mixture of the powder and a binder or plasma spraying the powder onto a substrate.

Abstract: The present disclosure is directed to a method of converting green particles to form finished particles. The apparatus used for sintering incorporates an elongate hollow tube, an insulative sleeve there about to define an elevated temperature zone, and a microwave generator coupled through a wave guide into a microwave cavity incorporated the tube. The particles are moved through the tube at a controlled rate to assure adequate exposure to the microwave radiation. Another form sintered a solid part in a cavity or mold.

Abstract: A method of producing Iron-Silicon high density sintered articles of intricate design comprising: (a) the blending of compressible iron or low-carbon steel powder, silicon alloyed iron or silicon powder, or combination of silicon alloyed iron and silicon powder, and lubricant, (b) cold pressing said blended mixture with pressures of less than 50 tsi to form the structure of said article with the density up to 88% of the theoretical value and with uniformly distributed hard powder consisting of silicon and/or silicon alloyed particles among ductile iron powder, (c) low temperature stress relieving heat treatment of said formed article at the temperature range of 360-800.degree. C. followed by a cooling rate of less than 120.degree. C.

Abstract: A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery.

Abstract: A process for producing a product made of a contact material. The contact material is formed of a powder mixture containing silver and iron as a main active component. The iron is an iron powder having an average particle size in excess of 1 .mu.m. Further processing of the powder mixture using powder metallurgy methods are performed for forming a product in which the iron has been oxidized to an iron oxide.

Abstract: A process for making a crystalline solid-solution powder which involves reacting at least two reactants in a plasma arc of a plasma chamber and blast-cooling the resultant product in a high velocity gas stream to form the powder. The first reactant is a molten metal alloy and the second reactant is a gas. The reaction is carried out in a plasma arc and the products rapidly cooled by a gas stream acting at the outlet opening of the plasma chamber. The crystalline solid-solution powder formed by the process has a low electrical resistivity. If an indium-tin alloy is used as the first reactant and oxygen as the second reactant, there is obtained an indium-tin-oxide (ITO) crystalline solid-solution powder which, when compacted to 40% of its theoretical density, has an electrical resistivity in the range of about 2 .OMEGA.cm. This ITO crystalline solid-solution powder is particularly suitable for preparing an ITO target, with high electrical conductivity and thus high achievable sputtering rates.

Abstract: The invention concerns a process for producing a low-oxygen, low-carbon iron-based powder. The process comprises the steps of preparing a powder essentially consisting of iron and optionally at least one alloying element selected from the group consisting of chromium, manganese, copper, nickel, vanadium, niobium, boron, silicon, molybdenum, tungsten, decarburizing the powder in an atmosphere containing at least H.sub.2 and H.sub.2 O gases, measuring the concentration of at least one of the carbon oxides (alternatively gases) formed during the decarburisation process, or measuring the oxygen potential in at least 2 points located at a predetermined distance from each other in the longitudinal direction of the furnace, adjusting the content of the H.sub.2 O gas in the decarburizing atmosphere with the aid of the measurement. Another alternative concerns measuring the carbon oxides in combination with measuring the oxygen potential.

Abstract: The methods of the present invention provide efficient mechanical milling or alloying of stock materials of titanium and aluminum in order to increase yield of the titanium stock and reduce cost in connection with the production of a titanium-aluminum-based alloy sinter. Sponge titanium, which has a particle size of 1 to 20 mm and which contains hydrogen at 3.5 mass % or more, is used as the titanium stock. The sponge titanium is ball-milled with an aluminum stock in an argon atmosphere to produce a hydrogen-containing titanium-aluminum-based alloy powder. Furthermore, this powder may be sintered, as required.

Abstract: An R--T--M alloy material, wherein R is at least one rare earth metal including Y, T is Fe or an Fe component partially replaced by Co or Ni, M is B or a B component partially replaced by C as primary components is prepared by heating the alloy at a temperature from room temperature to a specific temperature of less than 500.degree. C. in a non-oxidizing atmosphere and holding it at the given temperature, if necessary; performing hydrogenation by holding the alloy in a hydrogen atmosphere or a mixed gas atmosphere of hydrogen and an inert gas at a specific temperature in the range of 500-1,000.degree. C.; medial annealing the alloy by holding the R--T--M alloy after the hydrogenation step in an inert gas atmosphere at a specific temperature in the range of 500-1,000.degree. C.; and dehydrogenating the alloy by holding the alloy in a vacuum of less than 1 Torr for dehydrogenation, and then cooling the alloy.

Abstract: The stoichiometry and/or crystal structure of vanadium oxide particles are altered by heating initial particles of vanadium oxide under mild conditions. The temperature is generally at least about 300.degree. C. less than the melting point of both the initial vanadium oxide particle and the product vanadium oxide particles. Preferred initial particles are vanadium oxide nanoparticles. The heating can be performed under an oxidizing atmosphere or an inert atmosphere, depending on the particular initial particles and the desired product particles.

Abstract: This invention relates to a method for producing sintered parts of aluminum or aluminum alloy with improved mechanical properties using batch degassing, die compaction and liquid phase sintering. The batch degassing consists of holding a prealloyed aluminum powder at a temperature of about 350.degree. to about 450.degree. C. in a stainless steel autoclave in which the pressure is reduced to less than 5.times.10.sup.-6 torr. Once the desired pressure is reached the powder is cooled down within the autoclave while still under vacuum. The resulting powder is then compacted at a pressure of 20 to 50 tsi at between room temperature and about 250.degree. C., but preferably at a warm temperature of about 65.degree. C. The final densification is completed by liquid phase sintering in argon atmosphere at 625.degree. C. This method allows the production of sintered compacts characterized by a density close to 97% of theoretical, which makes it possible to eliminate the need for a hot working step.

Abstract: A milled tooth shaped rotary cone drill bit for drilling oil wells and the like manufactured using a powder metallurgy process in which an alloy powder is pressure molded into the desired bit shape, sintered, and precision machined.

Abstract: The object of the present invention is to provide an acid treatment for enhancing the high-rate discharge characteristic, cycle characteristic, and other characteristics of a hydrogen-absorbing alloy electrode to a large extent. The object can be achieved by subjecting a hydrogen-absorbing alloy as a negative electrode active material to an acid treatment comprising the steps of acid-treating the surface of the hydrogen-absorbing alloy by using a metallic ion-containing treatment solution which contains metallic ions and whose initial pH is in the range of 0.5 to 3.0; and heat-treating the hydrogen-absorbing alloy in an atmosphere with the presence of hydrogen.

Abstract: The quantity of impurities in a magnetic material is decreased to produce a magnetic material with good quality, and a decrease in the cost of the magnetic material is realized by desulfurization. A magnetic raw material for metallic thin film magnetic recording media which contains sulfur more than 20 ppm is desulfurized to obtain the magnetic material for metallic thin film magnetic recording media with the sulfur content adjusted to 20 ppm or below, and a metallic thin film magnetic recording medium having a magnetic layer vaporized thereon with the magnetic material is fabricated.

Abstract: Thermoelectric material for high temperature use made of a sintered body of a relative density of at least 75% consisting mainly of cobalt antimony compounds having an elemental ratio Sb/(Co+additives)=x of 2.7<x<3 is produced by a method of firing a shaped body of powders consisting mainly of cobalt and antimony in a non-oxidizing atmosphere under an environmental pressure, wherein the shaped body before the firing is constituted from crystal phases composed of a cubic crystal system compound CoSb.sub.3 (A phase), a monoclinic crystal system compound CoSb.sub.2 (B phase) and a hexagonal crystal system compound CoSb (C phase), and constitutional ratio of these crystal phases is (I.sub.B +I.sub.C)/(I.sub.A +I.sub.B +I.sub.C)<0.15 (wherein, I.sub.X (X is A, B or C) is a relative intensity by X-ray diffraction).

Abstract: A mechanochemical process for producing fine WC/Co composite powder which is so small in WC grain size and in mean free path, and contains such a uniform distribution of WC and Co that its hard metal is superior in strength, compressive strength, TRS and wear resistance and considerably free of impurities. The method comprises the steps of drying an ammonium metatungstate--Co(NO.sub.3).sub.2 solution in a spray dry manner to give initial powder of porous spheroids or in a common manner to give a cake of initial powder, removing the salts and humidity from the initial powder by a thermal treatment, mixing and milling the desalted initial powder with carbon black, and subjecting the mixed powder to reduction/carburization in a reactor.

Abstract: A method of fabricating a cathode member or pellet is provided, which realizes the sufficiently large increase of the electron emission capability by the current activation process and that prevents the maximum cathode current from being lowered as long as an electron emissive agent exists in the cathode member. First, (a) a nickel powder and a rare-earth-metal oxide powder are provided. (b) The nickel powder and the rare-earth-metal oxide powder are uniformly mixed together, thereby producing a first powder mixture. (c) The first powder mixture is heated in a hydrogen atmosphere, an inert atmosphere, or a vacuum atmosphere, thereby producing an intermetallic compound of nickel and the rare-earth metal in the first powder mixture. (d) The first powder mixture containing the intermetallic compound is uniformly mixed with an electron-emissive agent powder, thereby producing a second powder mixture. (e) The second powder mixture is sintered by a HIP process, thereby forming a cathode member.

Abstract: A process for producing a cutting die having a metal base which carries a sharpened ridge extending along a predetermined path thereon, in which a supply of powdered metal and a laser beam are moved along the path so as to surface melt a thin layer of the metal base with the metal powder and thus form a band of fused metal powder along the path, this step being repeated to form additional layers metallurgically bonded to the base and to each other, until a ridge of metal is formed. The ridge is then sharpened to suit it for use in cutting. The ridge may have a top surface of harder material than the inner part of the ridge. The laser and powder delivery movements may be controlled by a CNC (computer numerical control) motion system. The invention includes novel dies produced by this process.

Abstract: Articles produced by a powder metallurgy process involving forming of a shape by compaction followed by sintering without the application of external pressure from a stainless steel alloy powder produced by rapid atomization followed by an annealing treatment, which powder consists essentially of in weight percent, chromium 14-30, molybdenum 1 to 5, vanadium 0 to 5, tungsten 0 to 6, silicon 0 to 1.

Abstract: An electrical contact material for switching rated currents between 20 and 100 Ampere having improved operational life made of 3.2 to 19.9 wt-% tin oxide and 0.05 to 0.4 wt-%, in each case, of indium oxide and bismuth oxide, the remainder being silver. In the course of the manufacture of the material by powder metallurgy more than 60 wt-% of the tin oxide should exhibit a particle size of more than 1 .mu.m.

Abstract: The targets for cathodic sputtering according to this invention are formed of hot-pressed or hot isostatic-pressed indium oxide/tin oxide powder with a minimum density of 95% of the theoretical density and with a sub-stoichiometric oxygen content are known. In order to provide the improvement of high stability and, simultaneously, high sputtering rate, it is proposed according to the invention that the target have a crystalline phase which is formed as a solid solution of indium oxide and tin oxide with a minimum of 90% by weight, preferably a minimum of 97%, of the solid solution, and which has an average grain size ranging from 2 .mu.m to 20 .mu.m.

Abstract: A lubricant for metallurgical powder compositions contains an oligomer of amide type, which has a weight-average molecular weight M.sub.w of 30,000 at the most. A metal-powder composition containing the lubricant, as well as a method for making sintered products by using the lubricant, are also disclosed. Further, the use of the lubricant in warm compaction is described.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A method of fabricating a fully-dense three-dimensional metal article is disclosed. According to a first embodiment of the invention, the interior portion of the article is formed by way of selective laser sintering, in a cross-section of a layer of powder. After formation of the layer of powder, the laser is directed to form a gas-impervious skin around the interior portion of the article in that layer. The process is repeated, until the article is completed. The article surrounded by the skin is then subjected to hot isostatic pressing to densify the article; the skin, which serves as the "can" for the hot isostatic pressing, may or may not be removed from the article, as desired. According to a second embodiment of the invention, the can is formed first by way of laser generation, and is then filled with the metal powder, prior to hot isostatic pressing.

Abstract: A method and a device for heating powder, especially for preheating powder in view of subsequent compacting, are disclosed. The powder is divided into partial flows which are heated separately to a predetermined temperature. Then, the partial flows are brought together to form a common flow of heated powder. The partial flows are so heated that an uniform temperature is attained over essentially the entire cross-section of each of the partial flows before these are brought together. The device comprises a storage container (10) for the powder, and a heating unit (20) for receiving powder from the storage container (10) and heating it. The heating unit (20) comprises a plurality of spaced-apart heating surfaces (27) defining between them a plurality of flow channels (28) for the powder.

Abstract: A dispersion strengthened copper alloy and a method for producing the alloy are provided. The alloy preferably comprises aluminum, titanium and hafnium as alloying elements that are internally oxidized under controlled conditions to produce a dispersion strengthened copper material having good hardness and high conductivity. A method for reducing the adverse effects of hydrogen on such materials is also provided. The dispersion strengthened material can be useful in many applications, including welding electrodes and electrical contacts.

Abstract: A tool steel powder added with a vanadium carbide powder by a milling process, and a method for manufacturing parts therewith are disclosed. Particularly, a method for adding a vanadium carbide (VC) powder to a tool steel powder by a ball milling or an attrition milling, and a method for manufacturing a part by using the milled tool steel powder are disclosed. The method for manufacturing a vanadium carbide added tool steel powder and for manufacturing parts using the powder, includes the steps of: mixing a tool steel powder with vanadium carbide powder in an amount of 5.about.15 wt %; ball-milling the mixture powder under wet atmosphere; carrying out an annealing in a vacuum; carrying out a cold die compaction or cold isostatic pressing to near net dimension and carrying out a vacuum sintering and then a hot isotropic pressing without canning.

Abstract: The invention relates to a method of preparing a composite sintered body having inner and outer portions fitted with each other. The method includes the steps of: (a) preparing an inner powder compact; (b) preparing an outer powder compact; (c) fitting the inner and outer powder compacts with each other so as to prepare a composite powder compact; and (d) sintering the composite powder compact so as to prepare the composite sintered body. The inner and outer powder compacts are respectively selected such that, during the step (d), the amount of growth of the inner powder compact becomes greater than that of the outer powder compact. Each of the inner and outer composite powder compacts is made of one member selected from the group consisting of a wax-type segregation prevention powder mixture and a metal-soap-type segregation prevention powder mixture. At least one of the inner and outer composite powder compacts is made of the wax-type segregation prevention powder.

Abstract: A dispersion strengthened copper alloy and a method for producing the alloy are provided. The alloy preferably comprises aluminum, titanium and hafnium as alloying elements that are internally oxidized under controlled conditions to produce a dispersion strengthened copper material having good hardness and high conductivity. A method for reducing the adverse effects of hydrogen on such materials is also provided. The dispersion strengthened material can be useful in many applications, including welding electrodes and electrical contacts.

Abstract: A powder of diamond or high-pressure phase boron nitride core particles charged into a coating space as it is dispersed, and a precursor of a coat forming substance allowed to contact and/or impinge against the particles in the powder of core particles so that their surfaces are covered with the coat forming substance, thereby preparing coated diamond or high-pressure phase boron nitride particles which are subsequently sintered. The thusly produced diamond of high-pressure phase boron nitride sinter is composed of coated core particles of high performance that are superhard, uniform, dense and sintered firmly, and which have a controlled microstructure.

Abstract: A dispersion-strengthened aluminum alloy having a composite structure containing a matrix of .alpha.-aluminum and a precipitation deposited phase of an intermetallic compound with the intermetallic compound in a volume ratio of not more than 35 vol. %, has both high strength and high toughness. The precipitation phase of the intermetallic compound has an aspect ratio of not more than 3.0, the .alpha.-aluminum has a crystal grain size which is at least twice the grain size of the precipitation phase of the intermetallic compound, and the crystal grain size of the .alpha.-aluminum is not more than 200 nm. It is possible to obtain an aluminum alloy having the aforementioned limited structure by carrying out first and second heat treatments on gas-atomized powder containing at least 10 vol. % of an amorphous phase or a green compact thereof and thereafter carrying out hot plastic working.

Abstract: The invention relates to a process for preparing sintered shapes, comprising the steps of:(1) forming a green body from a mixture comprising a major amount of at least one inorganic powder; and one or more additives selected from the group consisting of: (A) at least one reaction product of a hydroxy compound with a carboxylic acylating agent; (B) at least one Mannich reaction product; (C) at least one hydrocarbyl-substituted amine; (D) at least one aminophenol; (E) at least one reaction product of a nitrophenol and amino compound; (F) at least one basic nitrogen-containing polymer; (G) at least one carboxylic acylating agent; (H) at least one aromatic acid or derivative thereof; (I) at least one aromatic oxime; and (J) at least one overbased or gelled overbased metal salt of an acidic organic compound provided that when the carboxylic acylating agent is a hydrocarbyl-substituted carboxylic acylating agent and the hydrocarbyl group contains less than an average of 40 carbon atoms, then the carboxylic acylatin

Abstract: According to the present invention, silicide grains are coupled with each other in a linked manner so as to provide a metal silicide phase, and grains forming a Si phase are dispersed in the gaps of the metal silicide phase discontinuously so as to provide a mixed structure of a sputtering target of high density and containing carbon at a rate less than 100 ppm. Because of the high density and high strength of the target, generation of particles at the time of sputtering can be reduced, and because of the reduced content of carbon, mixing of carbon in a thin film formed by the sputtering can be prevented.

Abstract: Graphite or carbon particles with a graphitic skin are intercalated with a compound including an oxidized form of a metal and then reduced in a hydrogen atmosphere. This process reduces the driving force for the galvanic reaction between the particles and active metals in aqueous environments. The particles may be present as a reinforcement for a metal matrix (e.g., graphite/aluminum metal matrix composites) or as a reinforcement for a non-metallic material (e.g., graphite/polyimide, graphite/polyester or graphite/cyanate composites). In the latter case, the composite is adjacent to a metal in a structure.By way of example, the graphite or carbon particle may be a fiber, the metal subject to attack may be aluminum or magnesium, and the intercalation compound may be NiCl.sub.2.

Abstract: A plunger charged as an electrode is received in a trough charged as a counter-electrode in order to heat material in the trough above the annealing temperature of metal material or the sintering temperature of ceramic-material. The trough and plunger are situated in a vacuum chamber separated from a condenser and pump stand by a valve. The plunger can be retracted into a cover of the chamber by a hydraulic drive on the cover. The cover, drive, and plunger are removable from the lower part of the chamber as a unit.