Abstract: A method for making multi-channel structures suitable for use as filters, catalyst carriers or the like.A composite rod comprising an outer shell and an inner core is formed of respective mixtures of powders. The mixture for the outer shell comprises a sinterable powdered structural material such as ceramics, metals, intermetallics, and a powdered binder such as paraffin, wax or polymer. The inner core comprises a powdered channel-forming filler material such as melamine or polymers, or soluble inorganic compounds or a metal that can differentially be removed from the structural material of the shell.The composite rod may be deformed, as by extrusion, to reduce its diameter. In any event, a bundle of composite rods is assembled and deformed, as by extrusion, to reduce the diameter of the bundle and of its component composite rods.

Abstract: Disclosed is a metal sulfide composition for use as a machining aid comprising 55.0% to 65.0% by weight of manganese, 29.0% to 36.0% by weight of sulfur, and greater than 2.0% to 10% by weight of iron. Also disclosed is a method of making the metal sulfide composition comprising mixing manganese, sulfur, and iron; initiating an exothermic reaction between the manganese and sulfur, wherein the iron component moderates and cools the exothermic reaction; forming a solid mass of manganese sulfide composition containing a portion of the iron suspended therein; and recovering the solid manganese sulfide composition. A method of using the manganese sulfide composition according to the present invention as a machining aid comprises mixing into a blend a desired metal powder with the manganese sulfide composition; spreading the blend into a metal part die; compacting the blend into the die; sintering the compacted part; and machining the sintered part.

Abstract: The present invention concerns a method, according to which powder compositions of iron-based particles are admixed with a thermoplastic material and a lubricant. The obtained mixture is compacted at a temperature below the glass-transition temperature or melting point of the thermoplastic resin and the compacted product is heated in order to cure the thermoplastic resin. Subsequently, the obtained compacted component is optionally heated to a temperature above the curing temperature.

Abstract: A method of free form fabrication of metallic components, typically using computer aided design data, comprises selective laser binding and transient liquid sintering of blended powders. The powder blend includes a base metal alloy, a lower melting temperature alloy, and a polymer binder that constitutes approximately 5-15% of the total blend. A preform part is built up, layer-by-layer, by localized laser melting of the polymer constituent, which rapidly resolidifies to bind the metal particles. The binder is eliminated from the preform part by heating in a vacuum furnace at low atmospheric pressure. The preform part may require support during elimination of the polymer binder and subsequent densification by controlled heat treatment. Densification is performed at a temperature above the melting point of the lower temperature alloy but below the melting point of the base metal alloy to produce transient liquid sintering of the part to near full density with desired shape and dimensional tolerances.

Abstract: A method for forming parts from inorganic particulate materials is diclosed. The method utilizes a two-component binder composition which is removable at a faster rate than conventional binder compositions, thereby reducing the formation of voids and cracks that occur during binder removal. No toxic materials are required and the method does not rely on solvents. The method may be used with ceramics, metals, and cermets.

Abstract: The present invention is a novel method for freeform fabrication. Specifically, the method of solid freeform fabrication has the steps of:(a) preparing a slurry by mixing powder particles with a suspension medium and a gelling polysaccharide;(b) making a layer by depositing an amount of said powder slurry in a confined region;(c) hardening a selected portion of the layer by applying a gelling agent to the selected portion; and(d) repeating steps (b) and (c) to make successive layers and forming a layered object. In many applications, it is desirable to remove unhardened material followed by heating to remove gellable polysaccharide then sintering.

Abstract: The method of the invention is concerned with the manufacture of a molded copper-chromium family metal based alloy article which involves the steps of injection-molding a mixture of copper powder, a chromium family metal powder, an iron family metal powder and a thermoplastic organic binder made up of a polymer binder and low molecular binder in a ratio by volume of 5:1 to 1:1, dewaxing a molded body formed by the injection-molding by heating in a reducing atmosphere, and then sintering the dewaxed molded body at 1,100.degree. to 1,450.degree. C. in a reducing atmosphere. According to this method, molded articles having a high dimensional accuracy and high density can be provided.

Abstract: A method of making a metal composite part by compacting a metal powder composition in a die whose wall surfaces have been electrostatically coated with a lubricant, thereby eliminating or reducing a lubricant in the metal powder composition, resulting in a metal composite having greater density and strength. The method further includes providing an electrostatic charge to the metal powder composition. A powder metallurgy apparatus is also provided.

Abstract: A mold useful for injection molding, comprising: a porous network of metal and oxidized metal and a cured epoxy resin dispersed in the porous network. The mold can be prepared by a process comprising the sequential steps of (a) forming a mixture of a metal powder and a polymer binder; (b) heating the mixture at a temperature in the range from about 100.degree. C. to about 300.degree. C. to remove a majority of the polymer binder from the mixture; (c) heating the mixture resulting from step (b) at a temperature greater than about 300.degree. C. and less than the melting point of the metal in the presence of oxygen to oxidize at least a portion of the metal to form a self-adhering porous network of metal and oxidized metal; (d) contacting the self-adhering porous network with an epoxy resin to fill at least a portion of the porous network with epoxy resin; and (e) curing the body resulting from step (d) to form the mold. The shape of the mold can be performed by selective laser sintering of the mixture.

Abstract: The present invention relates to an improved method of manufacturing an airbag initiator. Currently, an airbag initiator is comprised of three parts made out of two dissimilar materials plus a glass to metal seal. The present method builds the same airbag initiator with the body and the pins in one piece via a process called metal injection molding. The part is then placed in a furnace to remove a wax binder, then the temperature is ramped up slowly to remove a thermoplastic layer, and the temperature is further ramped up to form a sintered part. The sintered part being equal to or better than standards of wrought material. The initiator is then removed from the furnace and a glass bead is placed in a void area in the body of the initiator. The glass is melted forming a glass to metal seal between a first pin and the body of the initiator. A top portion of the initiator is then lapped off isolating the first pin from the body of the initiator.

Abstract: A plastically deformable aqueous mixture capable of being shaped into a body, the mixture being composed of any one or combination of ceramic, glass-ceramic, glass, molecular sieve, carbon, or metal powders, cellulose ether organic binder, water insoluble hydrophobic polymer co-binder having an average molecular weight of at least about 8,000, plasticizer, and water. A method of making a body which involves mixing the above components in a high shear mixer at a temperature of about 30.degree. C. to 70.degree. C. to form a homogeneous mixture, extruding the mixture at a temperature of about 30.degree. C. to 70.degree. C. into a green body, followed by drying and firing to produce the product body.

Abstract: The present invention relates to novel methods for shaping a filler material into a porous preform and subsequently filling at least a portion of the porous preform with a second material to form a composite body. Specific aspects of the invention include novel combinations of materials to form the preform in combination with novel processing techniques for shaping the combinations of materials into a porous preform.

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 new class of binders for binding finely divided inert inorganic molding particles when shaped into objects by known mechanical shaping techniques such as injection molding. The novel binders are solid polymer solutions containing a major fraction of a low molecular weight solid relatively non-volatile chemical as solvent in which is substantially dissolved a minor fraction of at least one high molecular weight solid polymer. The solid polymer solution binders when molten are homogeneous solutions and can be readily uniformly mixed with the usual inorganic molding particles into a readily flowable mixture which can be shaped and solidified. When solidified, the polymer and solid chemical remain a substantially homogeneous solution without appreciable phase separation.

Abstract: A two layer valve seat insert and a method for its manufacture is described. The method comprises the steps of preparing two powder mixtures; a first powder mixture for forming the valve seat face layer; a second powder mixture for forming the valve seat base layer; sequentially introducing a predetermined quantity of each of said first and said second powder mixtures into a powder compacting die and having an interface therebetween substantially perpendicular to the axis of said die; simultaneously compacting said first and said second powder mixtures to form a green compact having two layers and sintering said green compact, wherein at least one of the chemical composition or the physical characteristics of at least one of said first and said second powder mixtures is adjusted so as to result in said valve seat face layer and said valve seat base layer having substantially the same density after compaction.

Abstract: Process for producing multilayer ceramic substrates using greensheet technology and thin dielectric ceramic greensheets for miniaturization purposes. The process avoids the screening of the thin greensheets by forming self-supporting fusible particulate metal electrode layers, interposing them with the thin greensheets and sintering the assembly to form the multilayer substrates such as integrated capacitors.

Abstract: An apparatus and process for the free-forming manufacture of three-dimensal components. A powder-binder mixture, or a material with a high melting point, is plasticized or made molten, by raising the temperature inside a process chamber. The resulting molten material is discharged under pressure through a nozzle which is arranged at the end of the process chamber. The material inside the process chamber is deposited in layers. The processing direction and processing speed of the nozzle are programmed. An embodiment of the invention is disclosed in which a non-molten powder is deposited and supported by the deposition of a second powder alongside the non-molten powder.

Abstract: A process for preparing a metallic porous body, comprising: forming a layer comprising Cu, a Cu alloy, or a precursor thereof onto a skeleton composed of a porous resin body having a three-dimensional network, heat-treating the resin body with the layer formed thereon to remove a heat-decomposable organic component, thereby forming a porous metallic skeleton of Cu or a Cu alloy; and plating the surface of the Cu or Cu alloy skeleton with Ni or an Ni alloy. The heat treating may be carried out by direct induction heating. The metallic porous body is useful as electrodes for batteries, various filters, carriers for catalysts, etc. When the porous body is cut and used as the electrode substrate, the coating of an area, where Cu or its alloy has been exposed by cutting or the like, with a third metal having a lower ionization tendency than Cu or its alloy can provide an electrode substrate having better corrosion resistance and battery service life.

Abstract: Metallurgical powder compositions are provided which contain a metal powder in admixture with a solid, particulate polyether lubricant. The incorporation of the polyether lubricant enhances the green strength properties of compacted parts made from the powder compositions, and generally reduces the ejection forces required to remove the compacted part from the die cavity.

Abstract: The disclosure relates to a method of binder removal from a green body before sintering or the like wherein the green body is initially heated to a temperature above the melting or flow point of the binder to liquify the binder and, at the elevated temperature, a small portion of the green body is brought into intimate contact with a non-supporting porous body of lower capillarity potential for the liquid binder. The liquid is drawn from all parts of the green body to the region of contact between the porous body and the green body and enters the body of lower capillarity potential preferentially, removing liquid from the green body through the surface of the green body only at said region of contact. The draining is continued with or without further increase in temperature until the green body is opened or becomes permeable.

Abstract: Disclosed is a method of preparing a cemented carbide or a cermet alloy by mixing and kneading cemented carbide powder or cermet alloy powder with an organic binder, shaping this mixed powder into a prescribed configuration by an injection molding method and thereafter removing the organic binder from this compact and sintering the same, in order to obtain a dense alloy. Removal of the organic binder is performed in a first step in an inert gas atmosphere as a first removal step, and then continued in a second step in a vacuum of not more than 1 Torr. In the first removal step, the pressure is held in excess of the atmospheric pressure, to prevent the formation of imperfections in the compact. After continuous pores are formed in the interior of the compact, the atmosphere pressure is brought close to a vacuum, thereby facilitating the evaporation of gas from the surface and desorption of gas generated in the interior of the compact.

Abstract: The present invention discloses an improved method for compacting powdered materials, including ferrous alloys, non-ferrous metals or non-metal powders, wherein the improved method includes the use of an improved lubricant during the compaction process. The improved lubricant includes vinyl halides, generally, and polytetrafluroethylene, specifically. In a preferred embodiment of the present invention, 0.2 to 0.6 wt. % of the vinyl halide is added to the powdered form of the compactable material before the compaction and sintering of the compactable material.

Abstract: Thermoplastic binder compositions comprising a high molecular weight polymer component and a molten wax component are compounded with sinterable ceramic or other inorganic powders. Upon cooling, a thermally reversible gel is formed in the binder by the gelation of the polymer in the molten wax. Ceramic batches comprising these binders behave as shear-thinning and thermally reversible gels. They exhibit substantially improved dewaxing performance and, preferably, extensibility sufficient for sheet reforming processes.

Abstract: A method of producing a molded ceramic article comprises the first step mixing powdery raw materials and a liquid additive, thereby obtaining a mixed raw material, the second step press-molding the mixed raw material obtained in the first step in a hydrostatically applied condition of pressure, thereby removing an excess of the liquid additive to obtain a preform, and the third step calcining the preform obtained in the second step to obtain a molded ceramic article. The molded ceramic article comprises, as a principal component, copper and, as essential components, Cr and Ni within composition ranges of 0.1.ltoreq.Cr<2 wt. % and 0.1.ltoreq.Ni<10 wt. % and further at least one additive component selected from the group consisting of the following composition ratios: the following composition ratios: 0<Fe<5 wt. %, 0.ltoreq.Co<5 wt. %, 0.ltoreq.Al<10 wt. %, 0.ltoreq.Ti<20 wt. %, 0.ltoreq.Mo<3 wt. %, 0.ltoreq.Si<3 wt. %, 0.ltoreq.V<3 wt. %, 0.ltoreq.Mg<1 wt. %, and 0.ltoreq.

Abstract: The invention relates to(1) a method of preparing sintered shapes, comprising the steps of forming a green body from a mixture comprising (A) a major amount of at least one inorganic powder with (B) at least one reaction product of a alkanol-amine with a hydrocarbyl-substituted carboxylic acylating agent provided that when the hydrocarbyl group of the acylating agent contains less than 40 carbon atoms then the carboxylic acylating agent is a polycarboxylic acylating agent; and (2) sintering the body. Sintered shapes made from the methods of the present invention have relatively high fired densities and small uniform grain sizes; and low porosity. The reaction products of the present invention help disperse the inorganic powder. These reaction products also improve deagglomeration of the inorganic powder and help prevent reagglomeration of the powder.

Abstract: A metal casing for a semiconductor device is manufactured by a powder metallurgy injection molding process which uses infiltration. The metal casing includes a base member and an enclosure member arranged on the base member. The base member and the enclosure member are formed of an alloy including 20 to 50 percent by volume of copper, equal to or less than 1 percent by weight of nickel and remainder of tungsten or molybdenum. The metal casing is manufactured as a net-shape product by a process which includes the steps of mixing tungsten powder and nickel powder having average particles sizes equal to or less than 40 .mu.

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: The present invention provides a method of increasing debinding rates in Powder Injection Molding of metal and ceramic parts by use of a catalytic binding system.

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: A process is disclosed for producing an aluminum or an aluminum alloy sintering, comprising successive steps of maintaining a rare gas atmosphere inside a sintering furnace while heating a compact of aluminum particles or aluminum alloy particles, together with a magnesium source; reducing the pressure inside the sintering furnace while heating further for thereby sublimating magnesium nitrogen to generate Mg.sub.3 N.sub.2 and bringing the generated Mg.sub.3 N.sub.2 into contact with Al.sub.2 O.sub.3 in the surface of the compact for the reduction of Al.sub.2 O.sub.3, thereby effecting heating and sintering at a temperature lower than the melting point of aluminum. The process increases the bonding strength of the aluminum alloy particles while fully taking the advantage of a sintering process. Thus, it enables aluminum sinterings or aluminum-alloy sinterings improved in yield point, strength, and elongation.

Abstract: The target element (2) is formed from an inorganic compound layer (16) with a melting point above 300.degree. C. deposited on a foam or metallic felt support layer such that the layer of inorganic compound sinks to part of its depth into the support layer to define a composite layer (17). In order to form the target element, a precursor system of the inorganic compound is applied to the support layer, the assembly so formed is subjected to a pressure of between 0.1 MPa and 15 MPa, the resulting assembly is maintained at between 300.degree. C. and 1600.degree. C. and below the melting temperature of the support in order to obtain a sintered assembly. Said assembly is than cooled to an ambient temperature avoiding any sudden cooling. In order to produce the target, the element (2) is glued to a metallic substrate (4) using a conductive adhesive.

Abstract: A process of forming a sintered article for powder metal comprising blending carbon and ferro alloys and lubricant with compressible elemental iron powder, pressing said blended mixture to form sintering said article, and then high temperature sintering said article in a reducing atmosphere to produce a sintered article having a high density from a single compression.

Abstract: A process of coining sintered articles of powder metal comprising: blending carbon, ferro manganese, and lubricant with compressible elemental iron powder, pressing the blended mixture to form the articles, high temperature sintering of the articles in a reducing atmosphere and then coining the sintered articles to final shape so as to narrow the tolerance variability of coined articles and substantially eliminate secondary operations.

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: This invention consists of two parts: "Cemented Carbide with Minimal Amount of Binder Metal", and "Nonmagnetic cemented Carbide".The "Cemented Carbide with Minimal Amount of Binder Metal" is for cemented carbide bodies which are made from less than 2% binder metal powder and more than two kinds of metal carbide powder. Neither kind of carbide powder exceeds 98% of all the carbide powder used as raw material. The raw powder is to be prepared following a conventional powder metallurgy method--especially the conventional method of making cemented carbide--milling, cold pressing and non-high-pressure sintering. During the sintering process, metal carbide powder forms complicated solid solution carbides, and the small amount of binder which initially helped sintering is lost for the most part, if not entirely, during sintering.The "Non-magnetic Cemented Carbide" is cemented carbides which have nickel-tungsten alloy as a binder metal. The process of manufacturing uses said conventional powder metallurgy.

Abstract: Tantalum anode pellets or tantalum powders are treated to remove carbon content (mostly attributable to binders used in pressing the powders to pellet form and/or sintering of the pellets) by an aqueous leach at 50.degree.-200.degree. F. in lieu of the conventional complex distillation/decomposition methods.

Abstract: An inscribed planetary gear device usable as a speed reducer or an overdrive has a primary shaft which serves, for example, as an input shaft, an externally-toothed gear carried at an eccentricity by the primary shaft; an internally-toothed gear inscribed by the externally-toothed gear; and a secondary shaft which serves, for example, as an output shaft and connected to the externally-toothed gear, through an Oldham's ring which transmits to the secondary shaft only the rotation of the externally-toothed gear taking place about the axis of the externally-toothed gear. The externally-toothed gear is provided with a counter flange at an end facing the Oldham's ring and is operatively connected to the Oldham's ring through Oldham's projections and Oldham's grooves receiving Oldham's projections provided on the Oldham's ring and the counter flange, respectively, or vice versa.

Abstract: A secondary hardening type high temperature wear-resistant sintered alloy body comprising 0.4 to 15 wt. % of at least one species of metal carbide forming element which is selected from the group consisting of W, Mo, V, Ti, Nb, Ta and B; 5 to 35 wt. % of at least one species of austenite forming element which is selected from the group consisting of Ni, Co, Cu, and Cr; 0.2 to 1.2 wt. % of C; and 0.04 to 0.2 wt. % of Al consisting essentially the remainder of Fe, wherein the alloy body contains an austenite phase which is capable of martensitic transformation.

Abstract: The invention relates to a process for the manufacture by sintering of a titanium part, characterized in that is consists of:(a) mixing a titanium hydride powder with a temporary binding agent,(b) injecting the mixture obtained into a mold to obtain a part in the desired shape,(c) removing the binding agent,(d) heating the part in a hydrogen atmosphere up to the desired sintering temperature,(e) replacing the hydrogen atmosphere by a vacuum or a non-reactive atmosphere once the sintering temperature has been reached, and(f) cooling the part in a non-reactive gas atmosphere.

Abstract: An improved metallurgical powder composition capable of being compacted at elevated temperatures is provided comprising an iron-based powder, an alloying powder, a high temperature compaction lubricant, and a binder. The selected binders of this invention permit the bonded powder composition to achieve increased compressibility in comparison to unbonded powder compositions while reducing dusting and segregation of the alloying powder.

Abstract: The object of the invention is to provide a manufacturing method of a complex shaped R--Fe--B type sintered anisotropic magnet improved the moldability of injection molding and preventing the reaction between R ingredients and binder and controlled the degradation of magnetic characteristics due to residual carbon and oxygen. Utilizing the R--Fe--B type alloy powder or the resin coated said alloy powder, and methylcellulose and/or agar and water, instead of the usual thermoplastic binder, it is mixed and injection molded. The molded body is dehydrated by the freeze vacuum dry method to control the reaction between R ingredients and of the R--Fe--B alloy powder and water; furthermore, by administering the de-binder treatment in the hydrogen atmosphere, and sintering it after the dehydrogen treatment, residual oxygen and carbon in the R--Fe--B sintered body is drastically reduced, improving the moldability during the injection molding to obtain a three dimensionally complex shape sintered magnet.

Abstract: A method is presented for uniformly heating plastically deformable material, which comprises particles of electrically conducting matter. This method comprises inducing an electric current, or causing hysteresis loss within such material, by using electromagnetic radiation with frequency between about 50 Hertz and about 10 MegaHertz, to cause heating of the material.

Abstract: The disclosure relates to a binder, and the method of formulating the said binder, which is suitable for shaping parts from metallic and/or ceramic particles by injection molding. The binder comprises materials that are mainly thermoplastics, each of which having a percentage that is determined by its thermogravimetric analysis (TGA) profile and a weight loss versus highest binder removal rate from a green body by progressive heating. The removal of this binder from the green body is performed within a much shorter period of time than those published in the prior art. An example binder comprises 40-70% HDPE, 18-30% Paraffin wax, 10-25% microcrystalline wax and 2-5% stearic acid. Another binder comprises 35-65% PP, 23-35% paraffin wax, 10-25% microcrystaline wax and 2-5% stearic acid.

Abstract: A sintered electrode having fine pores and coarse pores and intended for use in a voltaic cell is made from reduced iron powder granules, which have been made from an iron(III) oxide powder having a particle size up to 10 micrometers and have a particle size not in excess of 500 micrometers and are compacted to form an electrode body, which is sintered under a reducing atmosphere at a sintering temperature up to 750.degree. C. The iron powder granules are derived from the agglomerated iron powder that is formed as the iron powder is reduced at 600.degree. to 800.degree. C. and optionally after the agglomerated iron powder has been reduced in size, and the iron powder granules before being compacted are mixed with an organic solid expanding agent, which volatilizes during the sintering process and is used in such a proportion and has such a particle size that the resulting sintered electrode has coarse pores in the desired number and the desired size.

Abstract: A process for producing a sintered body, comprising inserting a separately formed first molded article in a mold for injection molding, injection-molding a material identical to or different from that of the first molded article in the mold so that the injected material and the first molded article form together a second molded article, degreasing the second molded article, sintering the degreased article thereby obtaining a sintered body having a difference in shrinkage during the sintering between the first molded article and the injection molded portion of the second molded article other than the first molded article portion being 5% or less. The resulting sintered body is useful as a magnet base.

Abstract: A debinding method for use in a process for producing a sintered object, by effecting a debinding pre-treatment by heating the injection-molded object in an atmosphere of reduced pressure at a temperature at which the vapor pressure of the component of the organic binder having the highest vapor pressure does not exceed the pressure of the atmosphere, thereby removing the organic binder in the amount of at least about 18 wt %; and effecting a further debinding heat treatment in which the injection-molded object is heated to and maintained at a temperature higher than the temperature in the debinding pre-treatment.

Abstract: A process for thermal debinding and sintering of a workpiece made by molding a mixture of a binder and a powder, the process entailing the steps of injection molding a workpiece entailing at least 30% vol. of binder, the binder containing from about 70% to about 90% wt. of at least one wax and from about 10% to 30% wt. of high molecular weight polymer, introducing the molded workpiece in an enclosure at ambient temperature, injecting an atmosphere of at least 95% vol. hydrogen and less than 5% vol. water vapor, heating the enclosure and/or the workpiece until reaching a temperature between about 150.degree. C. to about 200.degree. C., maintaining the temperature during a period of time sufficient to substantially decompose all the waxes in the binder, then heating again the enclosure and/or the workpiece to reach a temperature of about 700.degree. C.

Abstract: A magnet base, having a flux density equal to that of an Fe-50%Co alloy and an input current response equal to that of an Fe--Si alloy, is used as a component of the magnetic circuit employed for a printing head of a wire dot printer, the magnetic circuit further having by-pass and armature components. The material of the magnetic base is an Fe-50% Co alloy and the base has an end face which is perpendicular to the magnetic circuit of the printing head. A layer, of a material selected from the class consisting of metals and metal alloys which function to increase the specific resistance of a magnet bases of an Fe-50% Co alloy, is formed on the end face of the magnet base and reduces eddy current loss therein, particularly at high frequency energization of the magnetic circuit, further serving to increase the input current response.

Abstract: The invention relates to (1) a method of preparing sintered shapes, comprising the steps of forming a green body from a mixture comprising (A) a major amount of at least one inorganic powder with (B) at least one reaction product of a alkanolamine with a hydrocarbyl-substituted carboxylic acylating agent provided that when the hydrocarbyl group of the acylating agent contains less than 40 carbon atoms then the carboxylic acylating agent is a polycarboxylic acylating agent; and (2) sintering the body. Sintered shapes made from the methods of the present invention have relatively high fired densities and small uniform grain sizes; and low porosity. The reaction products of the present invention help disperse the inorganic powder. These reaction products also improve deagglomeration of the inorganic powder and help prevent reagglomeration of the powder.

Abstract: An improved binder is mixed with powder to form feedstock for molding. The binder includes a first component which is soluble in water and a second component which is insoluble in water. The two binder components are miscible with each other in a liquid state. The two binder components form a uniform heterogeneous mixture when mixed in a liquid state. The binder is mixed with a suitable powder to form the feedstock. The feedstock is molded to form a compact. Polymer units of the binder are cross linked after the compact has been formed. The cross linking of the polymer units of a component of the binder is accomplished by exposing the compact to ultraviolet radiation or by the use of a catalyst. The compact is partially debound by exposing the compact to water, that is, to a water based solvent. Thereafter, the compact is further debound to remove the component which is insoluble in water. The powder is then sintered to form an article.