US2783208A - Powdered iron magnetic core materials - Google Patents

Powdered iron magnetic core materials Download PDF

Info

Publication number
US2783208A
US2783208A US401767A US40176754A US2783208A US 2783208 A US2783208 A US 2783208A US 401767 A US401767 A US 401767A US 40176754 A US40176754 A US 40176754A US 2783208 A US2783208 A US 2783208A
Authority
US
United States
Prior art keywords
powder
magnetic core
iron
naphthalene
powdered iron
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US401767A
Inventor
Katz George
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
RCA Corp
Original Assignee
RCA Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by RCA Corp filed Critical RCA Corp
Priority to US401767A priority Critical patent/US2783208A/en
Application granted granted Critical
Publication of US2783208A publication Critical patent/US2783208A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
    • C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
    • C23C22/07—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing phosphates
    • C23C22/08—Orthophosphates
    • C23C22/12—Orthophosphates containing zinc cations
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/20—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/22—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
    • H01F1/24—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49075—Electromagnet, transformer or inductor including permanent magnet or core
    • Y10T29/49076—From comminuted material

Definitions

  • This invention relates to magnetic. cores and more particularly to improved magnetic cores formed of compressed powderediron.
  • Magnetic cores made of compressed powdered iron, the individual particles of which are insulated from each other and bound together by resinous materials are well known. They are generally suitable for use as induction cores to operate at relatively high electrical frequencies.
  • One method of making such cores comprises mixing. powdered iron with a dilute solution of a polybasic inorganic acid such as sulfuric or phosphoric acid.
  • the iron is preferably, although not necessarily, prepared by the carbonyl process which produces relatively pure iron in the form of relatively small particles which may run about 3/L-1QLL in size. In many instances it is important that the iron particles be of a small size since eddy current losses in a compressed core decrease as the particle size decreases.
  • Treating the powder with polybasic acid produces an insulating coating upon the individual iron particles.
  • the powder is then mixed with a binder such as a phenol formaldehyde resin and molded into a desired shaped body.
  • One object of the instant invention is to provide an improved magnetic core.
  • Another object is to provide a compressed powdered i on magnetic core having improved electrical loss characteristics.
  • Another object isto provide a powdered iron magnetic core having improved physical strength and able to withstand relatively high stress.
  • Another object is to provide magnetic core bodies comprising powdered iron and having both improved strength and improved electrical loss characteristics.
  • improved core bodies may be produced by treating powdered iron with a polybasic acid solution that includes a relatively small proportion of a sulfonated derivative of naphthalene.
  • the treated powder is molded according to previous practice to form core bodies of improved strength and having improved electrical properties.
  • the single figure is a chart illustrating the improvement in properties provided by the practice of the instant invention.
  • a mass of carbonyl iron powder consisting essentially of iron particles about 3 u.10,u. in their greatest dimensions is wet with a solvent such as acetone that does not react with iron. About 50-100 cc. of acetone are used for each 100 gm. of iron powder. For purposes of convenience the present example described the treatment of 100 gm. of powdered iron. Larger quantities ably mixed in a mill such as a Simpson mixer.
  • a second mixture is prepared by dispersing about .02 gm. of 2,7 iso-propyl naphthalene sodium sulfonate in about 50-100 cc. of the same solvent used to wet the iron, conveniently, acetone. About 1-5 gm. of granodine is added to the acetone-sulfonate solution.
  • Granodine is a trade name for an aqueous 40% phosphoric acid solution that includes about 6%-12% by weight zinc phosphate.
  • the acetone-sulfonate-granodine mixture is added to the powdered iron and thoroughly mixed therewith.
  • the mixture is continuously stirred and, preferably, is heated to a temperature of about 40-50 C. to drive oif substantially all the acetone and water.
  • the mixing may be done in any convenient vessel such as a laboratory beaker. Larger quantities are prefer-
  • This treatment fnrms an insulating coating on the individual particles of the iron powder and prepares them for molding' with a resin.
  • a preferred resin is one that is known by the trade name of F-D-4-80M (manufactured by the Acme Resin Corporation, 1401 Circle Avenue, Forest Park, Illinois).
  • This product comprises a solution of about 60% phenol formaldehyde resin and 40% volatile solvent such as methyl alcohol. About 5 gm. of the resin solution is. diluted with about 50-100 cc. of acetone. The treated iron powder is wet down with about 50-100 cc. of acetone and the diluted resin solution is added to the Wet powder. The mixture is stirred continuously and gently heated to mix the resin and the iron powder intimately together and to drive oil the acetone and moisture. This mixing may be conveniently carried out in a Simpson mixer or other mill to produce pellets of about 18-20 mesh average size.
  • a molding lubricant consisting of about gm. of powdered zinc stearate or stearic acid is coated on the pellets by tumbling them in a barrel with the wax.
  • the pellets are then molded at about 50,000 lbs. per square inch pressure into bodies of a desired shape.
  • the bodies are heated at about 145 -155 C. for /2 hour or more to cure the resin.
  • An essential feature of the invention is the inclusion ot a sulfonated derivative of naphthalene in the granodine solution utilized in the initial treatment of the iron powder.
  • the naphthalene derivative is preferably included in the granodine in the proportions of about .01-.08 gm. per gm. of iron powder to be treated.
  • the other steps heretofore described are not critical in the practice of the invention but may be varied within the general limits customary in the art.
  • powdered iron produced by processes other than the carbonyl process may be utilized and the particle size of the iron is not critical.
  • other polybasic inorganic acids such as sulfuric acid may be utilized in place of phosphoric acid. t is generally important, however, that the iron powder be relatively clean and free from grease and other organic matter.
  • improved magnetic core bodies comprising powdered iron and a resin binder and also including relatively small proportions of a sulfonated naphthalene derivative. These bodies have improved strength and smaller electrical losses compared to previous bodies made in an exactly similar manner but without the sulfonated naphthalene derivative.
  • a method of making a compressed magnetic core body comprising the steps of wetting a mass of iron powder with a mixture comprising an aqueous solution of phosphoric acid and zinc phosphateand a substance selected from the group consisting of 2,7 iso-propylnaphthalene sodium sulfonate, the sodium salt of naphthalene 2,7 disulfonic acid, and Z-naphthalene sulfonic acid thereby, said substance being present in the proportions of about .01 to .08 gm. and said zinc phosphate being present in the proportion of about .06 to .60 gm. per 100 gms. of iron powder, to form an insulating coating upon the individual particles of said powder, drying said powder and molding said dried powder with a phenol formaldehyde resin binder to form a core body;

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Dispersion Chemistry (AREA)
  • Power Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Soft Magnetic Materials (AREA)

Description

Feb. 26, 1957 e. KATZ 2,783,208
POWDERED IRON MAGNETIC CORE MATERIALS Ffgled Jan; 4, 1954 QEAMS 2, 7 ISO-PEOPYL NAPHTHALENE SOD/UM SUI. FONATE PER I00 GRAMS POM DEE INVENTOR.
, George [(322 ATTORNEY 'POWDERED IRON MAGNETIC CORE MATERIALS ljnited States Patent George Kat'z,.'Philadelphia,,- Pa., assignor to Radio Corporation of America, a corporation of Delaware Application January 4, 1954; Serial No. 401,767 7 Claims. or. 252-625 This inventionrelates to magnetic. cores and more particularly to improved magnetic cores formed of compressed powderediron.
Magnetic cores made of compressed powdered iron, the individual particles of which are insulated from each other and bound together by resinous materials are well known. They are generally suitable for use as induction cores to operate at relatively high electrical frequencies. One method of making such cores comprises mixing. powdered iron with a dilute solution of a polybasic inorganic acid such as sulfuric or phosphoric acid. The iron is preferably, although not necessarily, prepared by the carbonyl process which produces relatively pure iron in the form of relatively small particles which may run about 3/L-1QLL in size. In many instances it is important that the iron particles be of a small size since eddy current losses in a compressed core decrease as the particle size decreases.
Treating the powder with polybasic acid produces an insulating coating upon the individual iron particles. The powder is then mixed with a binder such as a phenol formaldehyde resin and molded into a desired shaped body.
One object of the instant invention is to provide an improved magnetic core.
Another objectis to provide a compressed powdered i on magnetic core having improved electrical loss characteristics.
Another object isto provide a powdered iron magnetic core having improved physical strength and able to withstand relatively high stress.
Another object is to provide magnetic core bodies comprising powdered iron and having both improved strength and improved electrical loss characteristics.
These and other objects may be accomplished by the practice of the instant invention which provides an improved magnetic core body. It has now been discovered that improved core bodies may be produced by treating powdered iron with a polybasic acid solution that includes a relatively small proportion of a sulfonated derivative of naphthalene. The treated powder .is molded according to previous practice to form core bodies of improved strength and having improved electrical properties.
The invention will be described in greater detail in connection with the drawing of which:
The single figure is a chart illustrating the improvement in properties provided by the practice of the instant invention.
*According to a preferred embodiment of the instant invention a mass of carbonyl iron powder consisting essentially of iron particles about 3 u.10,u. in their greatest dimensions is wet with a solvent such as acetone that does not react with iron. About 50-100 cc. of acetone are used for each 100 gm. of iron powder. For purposes of convenience the present example described the treatment of 100 gm. of powdered iron. Larger quantities ably mixed in a mill such as a Simpson mixer.
'lce
may be treated with correspondingly larger quantities of the other materials involved.
A second mixture is prepared by dispersing about .02 gm. of 2,7 iso-propyl naphthalene sodium sulfonate in about 50-100 cc. of the same solvent used to wet the iron, conveniently, acetone. About 1-5 gm. of granodine is added to the acetone-sulfonate solution. Granodine is a trade name for an aqueous 40% phosphoric acid solution that includes about 6%-12% by weight zinc phosphate.
The acetone-sulfonate-granodine mixture is added to the powdered iron and thoroughly mixed therewith. The mixture is continuously stirred and, preferably, is heated to a temperature of about 40-50 C. to drive oif substantially all the acetone and water. For small batches the mixing may be done in any convenient vessel such as a laboratory beaker. Larger quantities are prefer- This treatment fnrms an insulating coating on the individual particles of the iron powder and prepares them for molding' with a resin. i
Any of a large number of phenol formaldehyde resins is satisfactory for molding core bodies according to the invention. A preferred resin is one that is known by the trade name of F-D-4-80M (manufactured by the Acme Resin Corporation, 1401 Circle Avenue, Forest Park, Illinois). This product comprises a solution of about 60% phenol formaldehyde resin and 40% volatile solvent such as methyl alcohol. About 5 gm. of the resin solution is. diluted with about 50-100 cc. of acetone. The treated iron powder is wet down with about 50-100 cc. of acetone and the diluted resin solution is added to the Wet powder. The mixture is stirred continuously and gently heated to mix the resin and the iron powder intimately together and to drive oil the acetone and moisture. This mixing may be conveniently carried out in a Simpson mixer or other mill to produce pellets of about 18-20 mesh average size.
A molding lubricant consisting of about gm. of powdered zinc stearate or stearic acid is coated on the pellets by tumbling them in a barrel with the wax.
The pellets are then molded at about 50,000 lbs. per square inch pressure into bodies of a desired shape. The bodies are heated at about 145 -155 C. for /2 hour or more to cure the resin.
An essential feature of the invention is the inclusion ot a sulfonated derivative of naphthalene in the granodine solution utilized in the initial treatment of the iron powder. The naphthalene derivative is preferably included in the granodine in the proportions of about .01-.08 gm. per gm. of iron powder to be treated. The other steps heretofore described are not critical in the practice of the invention but may be varied within the general limits customary in the art. For example, powdered iron produced by processes other than the carbonyl process may be utilized and the particle size of the iron is not critical. Also, other polybasic inorganic acids such as sulfuric acid may be utilized in place of phosphoric acid. t is generally important, however, that the iron powder be relatively clean and free from grease and other organic matter.
Improved but somewhat less satisfactory results may be produced by substituting other sulfonated naphthalene derivatives in place of the iso-propyl naphthalene sodium sulfonate heretofore described. For example, and 18% improvement in transverse strength may be provided in a core body when utilizing the sodium salt of naphthalene- 2,7 disulfonic acid in the proportion of about .04 gm. per 100 gm. iron powder. About a 10% improvement in strength is provided by Z-naphthalene sulfonic acid when utilized according to the invention in the proportions of about .01 gm. per 100 gm. iron powder. As may be seen from curve B of the figure, however, a 38% improvement in transverse strength is provided by the use of 2,7 iso-propyl naphthalene sodium sulfonate as described heretofore in connection with the preferred embodiment.
It should also be noted that the practice of the instant invention provides a significant improvement in the electrical loss characteristics of a magnetic core. As may be seen from curve A of the drawing, Q, an arbitrary inverse measure of electrical losses in a core body measured at 1 megacycle per second is improved about 4% by the practice of the preferred embodiment as described heretofore.
There have thus been described improved magnetic core bodies comprising powdered iron and a resin binder and also including relatively small proportions of a sulfonated naphthalene derivative. These bodies have improved strength and smaller electrical losses compared to previous bodies made in an exactly similar manner but without the sulfonated naphthalene derivative.
What is claimed is:
1. A method of making a compressed magnetic core body comprising the steps of wetting a mass of iron powder with a mixture comprising an aqueous solution of phosphoric acid and zinc phosphateand a substance selected from the group consisting of 2,7 iso-propylnaphthalene sodium sulfonate, the sodium salt of naphthalene 2,7 disulfonic acid, and Z-naphthalene sulfonic acid thereby, said substance being present in the proportions of about .01 to .08 gm. and said zinc phosphate being present in the proportion of about .06 to .60 gm. per 100 gms. of iron powder, to form an insulating coating upon the individual particles of said powder, drying said powder and molding said dried powder with a phenol formaldehyde resin binder to form a core body;
2. The method according to claim 1 in which said solution comprises 40% aqueous phosphoric acid and 6% to 12% by weight ofzinc phosphate in acetone.
3. The method according to claim 2 in which said substance selected from said group is 2,7 iso-propyl naphthalene sodium sulfonate.
4. A product prepared according to the process of claim 1 wherein said substance is a sodium salt of naphthalene 2,7 disulfonic acid.
5. A product prepared according to the process of claim 1 wherein said substance is 2-naphthalene sulfonic acid.
6. A product prepared according to the process of claim 1 wherein said substance is 2,7 iso-propyl naphthalene sodium sulfonate.
7. The product of claim 6 wherein said 2,7 iso-propyl naphthalene sodium su-lfonate is present in proportions of about .02 gm. per gms. of iron powder.
References Cited in the file of this patent UNITED STATES PATENTS 2,106,882 Betz Feb. 1, 1938 2,227,945 Neilson Jan. 7, 1941 2,306,198 Verweij et al. Dec. 22, 1942 2,601,212 Polydorofl. June 17, 1952 FOREIGN PATENTS 403,373 Great Britain Dec. 15, 1933 523,864 Great Britain July 24, 1940 OTHER REFERENCES Derksen, A. P. C. Spec. Serial No. 400,859, published April 27, 1943, 18-55M.

Claims (1)

1. A METHOD OF MAKING A COMPRESSED MAGNETIC CORE BODY COMPRISING THE STEPS OF WETTING A MASS OF IRON POWDER WITH A MIXTURE COMPRISING AN AQUEOUS SOLUTION OF PHOSPHORIC ACID AND ZINC PHOSPHATE AND A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF 2,7 IDO-PROPYL NAPHTHALENE SODIUM SULFONATE, THE SODIUM SALT OF NAPHTHALENE 2,7 DISULFONIC ACID, AND 2-NAPTHALENE SULFONIC ACID THEREBY, SAID SUBSTANCE BEING PRESENT IN THE PROPORTIONS OF ABOUT .01 TO .08 GM. AND SAID ZINC PHOSPHATE BEING PRESENT IN THE PROPORTION OF ABOUT .06 TO .60 GM. PER 100 GMS. OF IRON POWDER, TO FORM AN INSULATING COATING UPON THE INDIVIDUAL PARTICLES OF SAID POWDER, DRYING SAID POWDER AND MOLDING SAID DRIED POWDER WITH A PHENOL FORMALDEHYDE RESIN BINDER TO FORM A CORE BODY.
US401767A 1954-01-04 1954-01-04 Powdered iron magnetic core materials Expired - Lifetime US2783208A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US401767A US2783208A (en) 1954-01-04 1954-01-04 Powdered iron magnetic core materials

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US401767A US2783208A (en) 1954-01-04 1954-01-04 Powdered iron magnetic core materials

Publications (1)

Publication Number Publication Date
US2783208A true US2783208A (en) 1957-02-26

Family

ID=23589148

Family Applications (1)

Application Number Title Priority Date Filing Date
US401767A Expired - Lifetime US2783208A (en) 1954-01-04 1954-01-04 Powdered iron magnetic core materials

Country Status (1)

Country Link
US (1) US2783208A (en)

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2849312A (en) * 1954-02-01 1958-08-26 Milton J Peterman Method of aligning magnetic particles in a non-magnetic matrix
US2981811A (en) * 1957-08-22 1961-04-25 Gen Electric Circuit breaker
US3120699A (en) * 1962-07-19 1964-02-11 Ferro Corp Method for producing sintered ferrous article
US3120698A (en) * 1960-09-15 1964-02-11 Ferro Corp Powdered metal compositions and method
US3200007A (en) * 1962-10-24 1965-08-10 Ampex Method for making a magnetic recording medium
US3245841A (en) * 1961-08-31 1966-04-12 Clarke Sydney George Production of iron powder having high electrical resistivity
US3276921A (en) * 1962-09-24 1966-10-04 Michael W Freeman Compositions and articles including non-pyrophoric microparticles
US3533859A (en) * 1966-06-18 1970-10-13 Hooker Chemical Corp Coating process for ferrous metal surfaces
US3953251A (en) * 1974-03-25 1976-04-27 Bell Telephone Laboratories, Incorporated Method for the production of carbonyl iron containing magnetic devices with selected temperature variation
DE2827490A1 (en) * 1978-06-22 1980-01-17 Lev Veniaminovitsch Pevzner Ferromagnetic materials contg. phenolic resin binder - with fibrous filler, lubricant and iron powder
US4252679A (en) * 1979-11-19 1981-02-24 Exxon Research & Engineering Co. Preparation of magnetic catalysts (MSB-06)
US5063011A (en) * 1989-06-12 1991-11-05 Hoeganaes Corporation Doubly-coated iron particles
US5069972A (en) * 1988-09-12 1991-12-03 Versic Ronald J Moldable microcapsule that contains a high percentage of solid core material, and method of manufacture thereof
US5198137A (en) * 1989-06-12 1993-03-30 Hoeganaes Corporation Thermoplastic coated magnetic powder compositions and methods of making same
US5306524A (en) * 1989-06-12 1994-04-26 Hoeganaes Corporation Thermoplastic coated magnetic powder compositions and methods of making same
US5980603A (en) * 1998-05-18 1999-11-09 National Research Council Of Canada Ferrous powder compositions containing a polymeric binder-lubricant blend
US5982073A (en) * 1997-12-16 1999-11-09 Materials Innovation, Inc. Low core loss, well-bonded soft magnetic parts
WO2000030835A1 (en) * 1998-11-23 2000-06-02 Hoeganaes Corporation Annealable insulated metal-based powder particles and methods of making and using the same
WO2007084363A2 (en) 2006-01-12 2007-07-26 Hoeganaes Corporation Methods for preparing metallurgical powder compositions and compacted articles made from the same
US7510766B2 (en) 2003-02-05 2009-03-31 Corporation Imfine Inc. High performance magnetic composite for AC applications and a process for manufacturing the same
EP2963656A1 (en) * 2014-07-04 2016-01-06 Chang Mao Cheng Inductor and method of manufacturing the same
EP3480340A1 (en) * 2017-11-03 2019-05-08 The Boeing Company Iron particle passivation

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB403373A (en) * 1932-04-05 1933-12-15 James Harvey Gravell Improvements in or relating to metal cleaning compositions
US2106882A (en) * 1936-12-12 1938-02-01 Magnaflux Corp Paste of paramagnetic particles for use in the examination of paramagnetic materials for flaws by the magnetic method
GB523864A (en) * 1939-01-17 1940-07-24 Courtaulds Ltd Improvements in and relating to the manufacture and production of artificial threads and the like articles
US2227945A (en) * 1939-05-08 1941-01-07 Howard R Neilson Material and method for coating metals
US2306198A (en) * 1937-04-26 1942-12-22 Verweij Evert Johannes Willem Production of magnetic material
US2601212A (en) * 1948-11-09 1952-06-17 Gen Aniline & Film Corp Heat resistant magnetic cores and method of making

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB403373A (en) * 1932-04-05 1933-12-15 James Harvey Gravell Improvements in or relating to metal cleaning compositions
US2106882A (en) * 1936-12-12 1938-02-01 Magnaflux Corp Paste of paramagnetic particles for use in the examination of paramagnetic materials for flaws by the magnetic method
US2306198A (en) * 1937-04-26 1942-12-22 Verweij Evert Johannes Willem Production of magnetic material
GB523864A (en) * 1939-01-17 1940-07-24 Courtaulds Ltd Improvements in and relating to the manufacture and production of artificial threads and the like articles
US2227945A (en) * 1939-05-08 1941-01-07 Howard R Neilson Material and method for coating metals
US2601212A (en) * 1948-11-09 1952-06-17 Gen Aniline & Film Corp Heat resistant magnetic cores and method of making

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2849312A (en) * 1954-02-01 1958-08-26 Milton J Peterman Method of aligning magnetic particles in a non-magnetic matrix
US2981811A (en) * 1957-08-22 1961-04-25 Gen Electric Circuit breaker
US3120698A (en) * 1960-09-15 1964-02-11 Ferro Corp Powdered metal compositions and method
US3245841A (en) * 1961-08-31 1966-04-12 Clarke Sydney George Production of iron powder having high electrical resistivity
US3120699A (en) * 1962-07-19 1964-02-11 Ferro Corp Method for producing sintered ferrous article
US3276921A (en) * 1962-09-24 1966-10-04 Michael W Freeman Compositions and articles including non-pyrophoric microparticles
US3200007A (en) * 1962-10-24 1965-08-10 Ampex Method for making a magnetic recording medium
US3533859A (en) * 1966-06-18 1970-10-13 Hooker Chemical Corp Coating process for ferrous metal surfaces
US3953251A (en) * 1974-03-25 1976-04-27 Bell Telephone Laboratories, Incorporated Method for the production of carbonyl iron containing magnetic devices with selected temperature variation
DE2827490A1 (en) * 1978-06-22 1980-01-17 Lev Veniaminovitsch Pevzner Ferromagnetic materials contg. phenolic resin binder - with fibrous filler, lubricant and iron powder
US4252679A (en) * 1979-11-19 1981-02-24 Exxon Research & Engineering Co. Preparation of magnetic catalysts (MSB-06)
US5069972A (en) * 1988-09-12 1991-12-03 Versic Ronald J Moldable microcapsule that contains a high percentage of solid core material, and method of manufacture thereof
US5063011A (en) * 1989-06-12 1991-11-05 Hoeganaes Corporation Doubly-coated iron particles
US5198137A (en) * 1989-06-12 1993-03-30 Hoeganaes Corporation Thermoplastic coated magnetic powder compositions and methods of making same
US5306524A (en) * 1989-06-12 1994-04-26 Hoeganaes Corporation Thermoplastic coated magnetic powder compositions and methods of making same
US5543174A (en) * 1989-06-12 1996-08-06 Hoeganaes Corporation Thermoplastic coated magnetic powder compositions and methods of making same
US6340397B1 (en) 1997-12-16 2002-01-22 Materials Innovation, Inc. Method for making low core loss, well-bonded, soft magnetic parts
US5982073A (en) * 1997-12-16 1999-11-09 Materials Innovation, Inc. Low core loss, well-bonded soft magnetic parts
US6342108B1 (en) 1997-12-16 2002-01-29 Materials Innovation, Inc. Low core loss, well-bonded soft magnetic stator, rotor, and armature
US6129790A (en) * 1997-12-16 2000-10-10 Materials Innovation, Inc. Low core loss, well-bonded soft magnetic
US6251514B1 (en) 1997-12-16 2001-06-26 Materials Innovation, Inc. Ferromagnetic powder for low core loss, well-bonded parts, parts made therefrom and methods for producing same
US6309748B1 (en) 1997-12-16 2001-10-30 David S. Lashmore Ferromagnetic powder for low core loss parts
US5980603A (en) * 1998-05-18 1999-11-09 National Research Council Of Canada Ferrous powder compositions containing a polymeric binder-lubricant blend
WO2000030835A1 (en) * 1998-11-23 2000-06-02 Hoeganaes Corporation Annealable insulated metal-based powder particles and methods of making and using the same
US6372348B1 (en) 1998-11-23 2002-04-16 Hoeganaes Corporation Annealable insulated metal-based powder particles
US6635122B2 (en) 1998-11-23 2003-10-21 Hoeganaes Corporation Methods of making and using annealable insulated metal-based powder particles
US7510766B2 (en) 2003-02-05 2009-03-31 Corporation Imfine Inc. High performance magnetic composite for AC applications and a process for manufacturing the same
WO2007084363A2 (en) 2006-01-12 2007-07-26 Hoeganaes Corporation Methods for preparing metallurgical powder compositions and compacted articles made from the same
EP1976655A2 (en) * 2006-01-12 2008-10-08 Hoeganaes Corporation Methods for preparing metallurgical powder compositions and compacted articles made from the same
EP1976655A4 (en) * 2006-01-12 2010-07-07 Hoeganaes Corp Methods for preparing metallurgical powder compositions and compacted articles made from the same
EP2596883A1 (en) * 2006-01-12 2013-05-29 Hoeganaes Corporation Metal alloy powder composition, method of preparing powdr composition and compacted articles made thereof.
US8703046B2 (en) 2006-01-12 2014-04-22 Hoeganaes Corporation Methods for preparing metallurgical powder compositions and compacted articles made from the same
EP2963656A1 (en) * 2014-07-04 2016-01-06 Chang Mao Cheng Inductor and method of manufacturing the same
EP3480340A1 (en) * 2017-11-03 2019-05-08 The Boeing Company Iron particle passivation
US10774218B2 (en) 2017-11-03 2020-09-15 The Boeing Company Iron particle passivation

Similar Documents

Publication Publication Date Title
US2783208A (en) Powdered iron magnetic core materials
US2601212A (en) Heat resistant magnetic cores and method of making
US3451934A (en) Process of making molded magnetic material
US1982689A (en) Magnetic core material
US1946964A (en) Magnetic material and process of making the same
US2791561A (en) Magnetic powders and method of making the same
US11114228B2 (en) Magnetic powder composite, antenna and electronic device, and method for producing the same
US2886530A (en) Process of manufacturing ceramic ferrites
US2743309A (en) Thixotropic unsaturated alkyd resin compositions and members produced therewith
EP0166597A2 (en) Magnetic powder and production process thereof
Wijn et al. Note on the high frequency dispersion in nickel zinc ferrites
JPH0265103A (en) Resin binder for rare earth-iron and resin magnet using same
JPS55130103A (en) Process for producing dust magnetic material
US2306198A (en) Production of magnetic material
US3742423A (en) Electrical resistor
CN114210985A (en) Preparation method of high-magnetic-loss alloy absorbent
US3080243A (en) Basing cement
GB682897A (en) Improved magnetic powders and method of making the same
DE744149C (en) Process for the production of mass cores for magnetic cores, high frequency cores u. Like. Made of magnetizable metal powder
SU1591082A1 (en) Method of producing corbonyl iron-base magnetodielectrics
US2414417A (en) Production of heat-reactive resinous products
JPH0366254B2 (en)
TW202338113A (en) Method of preparing blank body wherein a mixture of a powder, a thermoplastic binder, a cross-linking agent, and a solvent is subjected to a granulation process, a molding process, and a heating process
JPS61263208A (en) Manufacture of magnetic molded unit
US1939301A (en) Insulated electrical conductor