Abstract: On producing a ferrite sintered body, there is used a ferrite powder having a median diameter D50 [?m] in a range from 0.1 to 0.8 ?m, a degree of spinel formation in a range from 45 to 90%, and a remanent magnetization Br per unit mass [emu/g] satisfying the following formula after application of the maximum magnetic field of 15 kOe:_0.05?Br?2.0(ln.D50)+6.3. The above ferrite powder allows producing a homogeneous ferrite sintered body generating very few cracks by gel casting.

Abstract: A method for making a composite magnetic-dielectric disc assembly includes forming a dielectric ceramic cylinder, forming a magnetic ceramic rod, assembling the magnetic ceramic rod coaxially inside the dielectric ceramic cylinder to form a rod-and-cylinder assembly, kilning (firing) the rod-and-cylinder assembly, slicing the rod-and-cylinder assembly to form a plurality of composite magnetic-dielectric disc-shaped assemblies. The magnetic-dielectric disc assemblies can be used in manufacturing, for example, circulators, isolators or similar electronic components. Accordingly, the method for making the disc assemblies can be included as part of a method for making such electronic components.

Abstract: A process for production of a magnet which comprises step of supplying a slurry S containing magnetic powder and a dispersing medium into the cavity C of a molding apparatus 12, a step of compression molding the slurry S while applying a magnetic field to the slurry S to obtain a molded article and a step of sintering the molded article to obtain a magnet, wherein the molding apparatus 12 comprises a die 121 having a through-hole 121a into which the slurry S is supplied, a slurry supply gate 121d being formed in the inner wall surface 121b, a die 122 inserted in the through-hole 121a and a die 123 that forms a cavity C together with the dies 123, 122, the slurry S being supplied in an amount such that it is less than the volume of the cavity C when the die 122 has been inserted in the through-hole 121a and has blocked the slurry supply gate 121d, and in the step of obtaining the molded article, the slurry S is compression molded after the die 122 has blocked the slurry supply gate 121d.

Abstract: A magnet encapsulated within a canister formed from two cans into a laminated structure particularly useful in plasma processing reactors. Each can includes an end wall and a cylindrical sidewall. One can additionally includes an annular lip that slidably fits outside the sidewall of the other can with a small gap therebetween. The magnet is inserted into the two cans together with a flowable and curable adhesive such as epoxy. The cans are slid together and compressed to cause the adhesive to flow between the magnet and the two cans and between the lip of one can and the sidewall of the other. The adhesive is cured to bond the magnet to the cans and to bond the cans together and to also hermetically seal the structure. The cans may be deep drawn from non-magnetic stainless steel with wall thicknesses of less than 0.064 mm.

Abstract: A manufacturing method of a magnetic device includes the steps of forming a magnetic substrate having a plurality of recesses, and forming at least one coil in the recess. In addition, a magnetic device is also disclosed. The magnetic device includes a magnetic substrate and at least one coil. The magnetic substrate has a plurality of recesses and the coil is disposed in the recess.

Abstract: The present invention provides a production method of a ferrite material comprising as main constituents Fe2O3: 62 to 68 mol %, ZnO: 12 to 20 mol %, and MnO substantially constituting the balance, wherein the method comprises a compacting step for obtaining a compacted body by using a powder containing the main constituents, the powder having a specific surface area falling within a range between 2.5 and 5.0 m2/g and a 90% particle size of 10 ?m or less, and a sintering step for sintering the compacted body obtained in the compacting step. Accordingly, the saturation magnetic flux density of the Mn—Zn based ferrite can be improved.

Abstract: A composite sintered magnetic material comprises a kind of metal powder at least one selected from the group consisting of Fe, Fe—Si type, Fe—Ni type, Fe—Ni—Mo type, and Fe—Si—Al type, and a ferrite layer formed from a kind of ferrite powder at least one selected from the group consisting of Ni—Zn type, Mn—Zn type, and Mg—Zn type, wherein a diffusion layer is formed by sintering between both of these to integrates the both.

Abstract: Magnetostrictive material based on cobalt ferrite is described. The cobalt ferrite is substituted with transition metals (such manganese (Mn), chromium (Cr), zinc (Zn) and copper (Cu) or mixtures thereof) by substituting the transition metals for iron or cobalt to form substituted cobalt ferrite that provides mechanical properties that make the substituted cobalt ferrite material effective for use as sensors and actuators. The substitution of transition metals lowers the Curie temperature of the material (as compared to cobalt ferrite) while maintaining a suitable magnetostriction for stress sensing applications.

Abstract: A ferrite sintered body is composed of an oxide containing, as metal element, at least Fe and Zn and at least one selected from Ni, Cu and Mn. This sintered body contain Fe of 42 to 50 mol % in terms of Fe2O3, and Zn of 15 to 35 mol % in terms of ZnO. When the Zn concentration in the sintered body interior is taken to be 1, the Zn concentration in the surface vicinity is 0.8 to 12. This increases the surface resistance of the ferrite sintered body and lowers its core loss.

Abstract: A stress stabilized ferrimagnetic material has a retained stress to provide enhanced initial permeability stability over a range of operating temperatures, such as from ?40° C. to 85° C., as well as pressures. Stress is introduced into the ferrimagnetic material, wherein subsequent processing relieves only a portion of the induced stress, and preferably less than 50% of the induced stress.

Abstract: The present invention provides a Mn—Zn ferrite which is low in the loss in the frequency range between a few 10 kHz and a few 100 kHz and high in the saturation magnetic flux density in the vicinity of 100° C. The present invention comprising the steps of compacting a powder having a specific surface area (based on the BET method) of 2.0 to 5.0 m2/g and a 50% particle size of 0.7 to 2.0 ?m into a compacted body having a predetermined shape and obtaining a sintered body by sintering the compacted body. It is preferable that a Mn—Zn ferrite comprises, as main constituents, 54 to 57 mol % of Fe2O3, 5 to 10 mol % of ZnO, 4 mol % or less (not inclusive of 0%) of NiO, and the balance substantially being MnO.

Abstract: A ferrite magnetic powder for bond magnet that experiences only small decrease in coercivity when molded into a bond magnet is provided, which is a ferrite magnetic powder that includes an alkaline-earth metal constituent and exhibits a decrease in coercivity of not greater than 600 Oe when subjected to a prescribed molding test. The magnetic powder can be obtained by mixing a fine ferrite powder of an average particle diameter of greater than 0.50 to 1.0 ?m and a coarse ferrite powder of an average particle diameter of greater than 2.50 to 5.0 ?m at ratio to incorporate the fine powder at a content ratio of 15-40 wt %.

Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1?xRx)O.n[(Fe1?yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01?x?0.4, [x/(2.6n)]?y?[x/(1.6n)], and 5?n?6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.

Abstract: An oxide magnetic material comprising main constituents including Fe2O3, ZnO, CuO and NiO. Y2O3 of 0.003 to 0.021 wt % and-ZrO2 of 0.06 to 0.37 wt % are included in main constituents with respect to all amounts. It is also preferable that Si of 0.010 to 0.0112 wt % is included in main constituents with respect to all amounts. Further, it is also preferable that Y2O3 of 0.001 to 0.011 wt % , ZrO2 of 0.031 to 0.194 wt %, and Si of 0.010 to 0.056 wt % are included in main constituents with respect to all amounts.

Abstract: An oxide magnetic material is prepared by wet molding in a magnetic field a slurry containing a particulate oxide magnetic material, water and a polyhydric alcohol having the formula: Cn(OH)nHn+2 wherein n is from 4 to 100 as a dispersant. By improving the orientation in a magnetic field upon wet molding using water, an oxide magnetic material having a high degree of orientation, typically an anisotropic ferrite magnet, is obtained at a high rate of productivity. The method is advantageous from the environmental and economical standpoints.

Abstract: The present research provides a high-density magnetic ceramic composition for microwave application and a preparation method thereof. The magnetic ceramic composition of this research includes Yttrium iron garnet (YIG, Y3Fe5O12) as its basic element and a little amount of additional element, silicon oxide (SiO2), which is expressed as: Y3Fe5O12+x SiO2 (0.05?x?5 mol %). The magnetic ceramic composition is prepared by measuring proper amounts of ferric oxide (Fe2O3), yttrium oxide (Y2O3) and SiO2, mixing them, calcining the mixture, and molding and sintering them. Since the magnetic ceramic composition of the present research has very little magnetic loss, it can be used in components for communication in a microwave band, usefully.

Abstract: Organic solvent-based photothermographic materials comprise one or more mercaptotriazoles represented by the following Structure I as toner(s): wherein R1 and R2 independently represent hydrogen, or an alkyl, aryl, aralkyl, alkenyl, cycloalkyl, or aromatic or non-aromatic heterocyclyl group, M is hydrogen or a cation, or R1 and R2 taken together can form a saturated or unsaturated heterocyclic ring, or still again, R1 and R2 taken together can represent a divalent linking group, provided that R1 and R2 are not simultaneously hydrogen or an unsubstituted phenyl group, and further provided that when R2 is hydrogen, R1 is not a methyl or phenyl group having a solubilizing substituent.

Abstract: In the method for manufacturing ferrite type permanent magnets according to the formula M1-xRxFe12-yTyO19: a) a mixture of the raw materials PM, PF, PR and PT of elements M, Fe, R and T, respectively, is formed, Fe and M being the main raw materials and R and T being substitute raw materials; b) the mixture is roasted to form a clinker; c) wet grinding of said clinker is carried out; d) the particles are concentrated and compressed in an orientation magnetic field to form an anisotropic, easy to handle green compact of a predetermined shape; and e) the anisotropic green compact D is sintered to obtain a sintered element. The surface are GS and percentage of at least one of the substitute raw materials is selected according to the surface area and percentage of the iron raw material to obtain magnets with high squareness and overall performance index properties.

Abstract: Disclosed is a thermally processed image recording material containing, on one side of a support having an image-forming layer, a silver salt of an organic acid, a reducing agent and at least one kind of a compound represented by the following formula (1): wherein X and Y represent an electron-withdrawing group and M represents a counter cation, and the conjugate acid of the enolate anion in the formula (1) has a pKa value of 3.0-6.0. This thermally processed image recording material shows low fog, high Dmax, ultrahigh contrast and good storage stability.

Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1−xRx)O.n[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, and substantially having a magnetoplumbite crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.

Abstract: A method including mixing powders of at least one of MgO, Mg(OH)2, and MgCO3, and powders of Fe2O3, CuO and ZnO, pre-sintering the mixed powder at 900° or lower, milling the pre-sintered raw powder, pressing the milled powder to form a pressed body and sintering the pressed body to form a magnetic ferrite powder such as MgCuZn, MgNiCuZn, or NiCuZn.

Abstract: A method of making a magnetoplumbite-type ferrite material powder includes the step of preparing the ferrite material powder by spraying a mixed chloride solution, in which a chloride of iron and a chloride of strontium are dissolved, into a heated atmosphere. The solution of the mixed chloride contains 25% through 35% of the chloride of iron and 2.4% through 4.9% of the chloride of strontium.

Abstract: A ferrite magnet having a basic composition represented by the following general formula: (A1-xRx)O.n[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba, R is at least one of rare earth elements including Y, M is at least one element selected from the group consisting of Co, Mn, Ni and Zn, and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, and substantially having a magnetoplumbite-type crystal structure, is obtained by uniformly mixing a compound of Sr and/or Ba with an iron compound; calcining the resultant uniform mixture; adding a compound of the R element and/or the M element to the resultant calcined powder at a pulverization step thereof; and sintering the resultant mixture. The compound of the R element and/or the M element may be added at a percentage of more than 0 atomic % and 80 atomic % or less, on an element basis, at a mixing step before calcination.

Abstract: An oxide magnetic material comprising main constituents including Fe2O3, ZnO, CuO and NiO. Y2O3 of 0.003 to 0.021 wt % and-ZrO2 of 0.06 to 0.37 wt % are included in said main constituents with respect to all amounts. It is also preferable that Si of 0.010 to 0.0112 wt % is included in said main constituents with respect to all amounts. Further, it is also preferable that Y2O3of 0.001 to 0.011 wt % , ZrO2 of 0.031 to 0.194 wt %, and Si of 0.010 to 0.056 wt % are included in said main constituents with respect to all amounts.

Abstract: A production process of a Mn—Zn ferrite enables wastes of sintered cores to be recycled without serious difficulties in sintering. The production process includes recycling a powder obtained by milling a sintered Mn—Zn ferrite, thereby obtaining a sintered core having a component composition including 44.0 to 49.8 mol % Fe2O3, 4.0 to 26.5 mol % ZnO, 0.02 to 1.00 mol % Mn2O3 and a remainder MnO.

Abstract: The invention concerns a process for the preparation of an insulated soft magnetic powder comprising the steps of mixing particles of a soft magnetic iron base powder with an acidic, aqueous insulating-layer forming solution, in which MgO has been dissolved; and drying the obtained mixture to obtain an electrically insulating Mg containing layer on the particle surfaces. The invention also concerns the powder per se as well as compressed soft magnetic powder cores prepared from the powder.

Abstract: Methods of making metal oxide articles, preferably iron oxide articles, and articles thereby produced. The method comprises the steps of slightly pressing powder to a compact, the powder consisting essentially of a first oxide of the metal; and subjecting the compact to a heat treatment that causes the powder to sinter into a unitary body and results in the transformation of at least a portion of the first oxide to a second oxide by oxidation or deoxidation during the heat treatment. In disclosed embodiments, the heat treatment is conducted either in air at atmospheric pressure or at a subatmospheric pressure. The method optionally includes more heating/cooling steps resulting in additional oxidation/deoxidation cycles. Sintered iron oxide articles of the invention have high mechanical strengths and interconnected pore structures, providing for efficient filtering of liquids and gases.

Abstract: A health support device having a lamination of a semiconductor film on a surface of a partially-reduced sintered material of titanium oxide. The semiconductor film is preferably a p-type semiconductor film of silicon or germanium. The partially-reduced sintered material is preferably represented by TiO2−x, where 0<×<0.5. The thickness of the semiconductor film is preferably from 1 nm to 500 nm. In production, a mixture of a titanium oxide powder and a binder is press-molded, and the molded material is sintered at a temperature of from 500° C. to 1100° C. in a vacuum, inert or reducing atmosphere. A p-type semiconductor film is formed on a surface of the resulting partially-reduced sintered material of titanium oxide.

Abstract: A method of a manufacturing rotating electromagnetic component to have both soft and hard (permanent) magnet regions, in which powder technologies are used to net-shape mold the component. A soft magnet powder material and an insert or powder of a permanent magnet material are compacted to form a rotating electromagnetic body containing soft and hard magnet regions. A partial sintering operation is then performed on the body at a temperature of 1600° F. (about 870° C.) or less, preferably about 1400° F. to 1500° F. (about 760° C. and 830° C.), and most preferably at 1500° F. to at least partially fuse the soft magnet powder materials with the permanent magnet material. The soft powder component of the resulting electromagnetic body is sufficiently fused to exhibit mechanical properties comparable to a fully sintered body (i.e., sintered at 2050° F. (about 1120° C.) or more), but without degrading the magnetic properties of the hard magnet region.

Abstract: A process for producing Mn—Zn ferrite having large electrical resistance and being durable to the use in high frequency region exceeding 1 MHz easily and at low cost is disclosed. The process comprises pressing a mixed powder comprising a composition of 44.0 to 50.0 mol % of Fe2O3, 4.0 to 26.5 mol % of ZnO, 0.1 to 8.0 mol % of at least one member selected from the group consisting of TiO2 and SnO2, and the remainder being MnO, and if desired 0.1 to 16.0 mol % of CuO, sintering the resulting green compact in the air or an atmosphere containing an appropriate amount of oxygen, and then cooling the green compact, thereby securing the estimated high initial permeability even in a high frequency region of 1 MHz or more.

Abstract: Provided are a method for preparing an Ni—Cu—Zn ferrite powder having excellent sinterability at a lower temperature, and a method for producing a laminated chip inductor from the above ferrite powder. The method for preparing the ferrite powder is a method for the preparation of a soft magnetic ferrite powder composed of Fe, Ni, Cu and Zn as main components, and comprises the step of allowing an organic additive to be present in a slurry containing a calcined product of a starting powder and water, wherein the organic additive is an organic compound having a hydroxyl group and a carboxyl group or a neutralization salt or lactone thereof, or the organic additive is an organic compound having a hydroxymethylcarbonyl group, an organic compound having an enol type hydroxyl group dissociable as an acid or a salt thereof.

Abstract: The invention aims to provide a manganese-zinc ferrite exhibiting a high initial permeability over a broad band and especially in a low-frequency region of about 10 kHz and a method for preparing the same. A method for preparing a manganese-zinc ferrite by firing is characterized in that the firing includes a main temperature holding step at 1,200-1,450° C. and a thermal ramp-down step prior to the main temperature holding step, and the lowest temperature reached by the mid-firing thermal ramp-down step is set in the range of 1,000-1,400° C. and lower by at least 50° C. than the hold temperature of the main holding step, thereby obtaining a manganese-zinc ferrite comprising 50-56 mol % calculated as Fe2O3 of iron oxide, 22-39 mol % calculated as MnO of manganese oxide, and 8-25 mol % calculated as ZnO of zinc oxide as main components, and having a mean crystal grain size of more than 50 &mgr;m to 150 &mgr;m.

Abstract: A process for producing Mn—Zn ferrite is disclosed, which enables regeneration and reuse of scraps of a sintered product. The process comprises reusing a powder obtained by milling the sintered product of Mn—Zn ferrite, subjecting the powder to a component adjustment so as to have a composition of 44.0 to 50.0 mol % of Fe2O3, 4.0 to 26.5 mol % of ZnO, 0.1 to 8.0 mol % of at least one member selected from the group consisting of TiO2 and SnO2, and the remainder being MnO, and optionally 0.1 to 16.0 mol % of CuO, pressing the resulting mixed powder after the component adjustment, and then sintered a green compact.

Abstract: The invention concerns a process for the preparation of an insulated soft magnetic powder comprising the steps of mixing particles of a soft magnetic iron base powder with an acidic, aqueous insulating-layer forming solution, in which MgO has been dissolved; and drying the obtained mixture to obtain an electrically insulating Mg containing layer on the particle surfaces. The invention also concerns the powder per se as well as compressed soft magnetic powder cores prepared from the powder.

Abstract: Magnetic material has a ceramics having a composition in the range of Fe2O3 35.0 to 44.5 mol %, NiO 47.0 to 56.5 mol % and CuO 5.0 to 12.0 mol %, and the ceramics having relative magnetic permeability of 15 or less, and composes the inductance element comprising this magnetic material and the internal metallic conductor. For making laminated inductance elements by concurrently baking ceramic green sheets and internal metallic conductors, substances to be used as ceramic green sheets, which substances have the composition in the above mentioned range are used, and a silver or silver alloys are used as the internal metallic conductor, and the calcination is carried out at temperature of 880 to 920° C.

Abstract: A method of manufacturing a ferrite sintered body includes the steps of: adding B4C in a ferrite raw material and firing the ferrite raw material, whereby the ferrite sintered body has a high &mgr;i and a high Q, is less irregular in its characteristics, has a high volume resistivity and is capable of preventing deterioration of insulating resistance.

Abstract: Ceramic-coated powdered ferromagnetic materials for forming magnetic articles, and which maintain the mechanical and magnetic properties of the articles at high temperatures, such as during annealing to relieve stresses induced during the forming operation. The ceramic coatings are formed by one of several techniques to provide an encapsulating layer on each ferromagnetic particle. The particles are then compacted to form a solid magnetic article, which can be annealed without concern for degrading the ceramic coating.

Abstract: Disclosed is a method for the preparation of a ferrite beads composition suitable for compression-molding into a compression-molded ferrite body to be subjected to a sintering heat treatment to give a sintered ferrite member having usefulness as an electromagnetic material. The method comprises the steps of: forming ferrite beads from ferrite particles and an organic binder compound; and uniformly mixing the ferrite beads with a limited amount of a higher fatty acid ester of a hexitan compound such as sorbitan mono- or sesquioleate. The ferrite beads composition of the invention is advantageous not only in respect of the behavior in compression molding such as high density of the compression-molded body, low withdrawal pressure from the metal mold and a decrease in the phenomenon of springback but also in respect of the properties of the ferrite body after sintering.

Abstract: The process for the preparation of an oxide magnetic compact of the invention comprises:a step of preparing a mixed material which comprises 44 to 50 mole % of iron calculated as Fe.sub.2 O.sub.3, 0.1 to 8 mole % of manganese calculated as Mn.sub.2 O.sub.3, with the sum of iron and manganese being 50 to 54 mole % calculated as Fe.sub.2 O.sub.3 and Mn.sub.2 O.sub.3, 20 to 38 mole % of magnesium calculated as MgO, 17 to 22 mole % of zinc calculated as ZnO and not more than 5 mole % of copper calculated as CuO, anda step of molding the aforesaid mixed material to a predetermined shape and then firing it in an atmosphere of low oxygen concentration of 2.5 to 12% by volume. Therefore, there appears an extremely excellent effect that the oxide magnetic compact having excellent electromagnetic properties can be obtained at low cost.

Abstract: The magnetic powder and the sintered magnet of the invention contains a primary phase of a hexagonal ferrite containing A, Co or R wherein A represents Sr, Ba or Ca, and R represents at least one element which may be rare earth elements including Y, and Bi, and have at least two different Curie temperatures, wherein the two different Curie temperatures are present within a range of from 400 to 480.degree. C., and an absolute value of a difference therebetween is 5.degree. C. or more. As both the saturation magnetization and the magnetic anisotropy of the M type ferrite therein are increased, the magnetic powder and the wintered magnet have a high residual magnetic flux density and a high coercive force, which conventional M type ferrite magnets could not have, while having excellent temperature characteristics of coercive force.

Abstract: A method for producing shaped bodies from hard ferrites, includes (a) providing a powder of hard ferrite material having a fine particle size; (b) adding to the powder a plastifying and bonding agent which comprises (a) at least one of cyclododecane, cyclododecanol, and stearyl alcohol and (b) stearic acid to provide a mixture; (c) shaping the mixture into a blank; (d) heating at a temperature effective to remove the plastifying and bonding agent from the blank; and (e) subsequently heating the blank to a temperature effective to sinter the powder. The method is suitable for the production of magnets, in particular segmental magnets.

Abstract: The method of the invention uses a molding slurry containing a particulate oxide magnetic material and water and having a dispersant added thereto. The dispersant is an organic compound having a hydroxyl group and a carboxyl group or a neutralized salt thereof or a lactone thereof, an organic compound having a hydroxymethylcarbonyl group, or an organic compound having an enol form hydroxyl group dissociable as an acid or a neutralized salt thereof. The organic compound has 3 to 20 carbon atoms, with the hydroxyl group being attached to at least 50% of carbon atoms other than the carbon atom forming a double bond with an oxygen atom. Citric acid or a neutralized salt thereof is also useful as the dispersant. The addition of the dispersant facilitates the wetting of the particulate oxide magnetic material with water and improves the dispersion of primary particles and a degree of orientation upon molding.

Abstract: A compound magnetoresistance effect material which is an oxide containing thallium(Tl) and manganese(Mn); wherein the oxide has a composition of Tl.sub.2 Mn.sub.2 O.sub.y where y represents seven or a value near to seven which varies depending on a combination of components of the oxide, a composition ratio between the components and conditions in synthesis of the oxide and has a pyrochlore structure.

Abstract: A ceramic composition for absorbing electromagnetic waves and a method for manufacturing the same are disclosed. The composition comprises a raw powder comprising by weight between about 60% and about 80% Fe.sub.2 O.sub.3, between about 3% and about 8% NiO, between about 15% and about 25% ZnO, and between about 3% and about 8% CuO, and a mixture around the raw powder comprising by weight between about 30% and about 50% water, between about 0.2% and about 0.6% a dispersing agent, between about 0.5% and about 1.0% a plasticizer, and between about 0.1% and about 0.4% a lubricant. The method comprises the steps of grinding the powder, converting the grounded powder into granulates, forming the granulates into a shaped body, sintering the shaped body in a furnace, and cooling the sintered body gradually. The ceramic composition can absorb much of the electromagnetic waves generated from electric devices such as cellular phones, beepers, computers, wireless telephones, etc.

Abstract: A process for forming a ceramic coated element formed by first encapsulating the element within a sacrificial material and then encapsulating the element and the sacrificial material with an unsintered ceramic material. The resultant combination of materials and elements is then controllably heated to a temperature that burns the sacrificial material prior to the curing of the ceramic material so as to permit the permeation of the burned sacrificial material through the ceramic material. As the ceramic material is sintered it shrinks around the encapsulated element to form the ceramic coated element. In the preferred embodiment of the invention the coated element is a magnet or magnetizable material that is magnetized to a preferred axis of magnetization during the cooling phase of the process.

Abstract: A process for producing ultra-fine yttrium-iron-garnet particles. In the first step of this process, a ceramic precursor material containing yettrium and ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A process for producing ultra-fine barium hexaferrite particles. In the first step of this process, a ceramic precursor material containing barium and trivalent ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A slurry containing ferrite magnet raw material particles and a non-aqueous solvent is compacted wet in a magnetic field, while said non-aqueous solvent is removed therefrom, to obtain a compact, and the compact is sintered to obtain an anisotropic ferrite magnet. In this case, a surface active agent is allowed to exist in the slurry during the wet compaction. Alternatively, in addition to or in place of this, the raw material particles are pulverized to apply strains thereto, thereby reducing the iHc values to preferably 3.5 kOe or less. This makes some considerable improvement in the degree of orientation of the compact, thus achieving much more improved magnet properties.

Abstract: A method and apparatus for establishing the magnetic permeability of a batch ferrites at a predetermined target permeability. Ferrite parts are sintered to achieve a magnetic permeability greater than the target permeability. The sintered parts are then tumbled to suppress the magnetic permeability below the target permeability. The parts are then exposed to a chemical wash to increase the magnetic permeability and continuously monitored to allow setting the magnetic permeability at the target permeability.