NL7018910A - Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually - Google Patents

Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually

Info

Publication number
NL7018910A
NL7018910A NL7018910A NL7018910A NL7018910A NL 7018910 A NL7018910 A NL 7018910A NL 7018910 A NL7018910 A NL 7018910A NL 7018910 A NL7018910 A NL 7018910A NL 7018910 A NL7018910 A NL 7018910A
Authority
NL
Netherlands
Prior art keywords
powder
temp
mass
limited amount
gradually
Prior art date
Application number
NL7018910A
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 filed Critical
Priority to NL7018910A priority Critical patent/NL7018910A/en
Publication of NL7018910A publication Critical patent/NL7018910A/en

Links

Classifications

    • 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
    • H01F1/032—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 hard-magnetic materials
    • H01F1/04—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 hard-magnetic materials metals or alloys
    • H01F1/06—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 hard-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/061—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 hard-magnetic materials metals or alloys in the form of particles, e.g. powder with a protective layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/14—Treatment of metallic powder
    • B22F1/145—Chemical treatment, e.g. passivation or decarburisation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Powder Metallurgy (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

Passivation of a mass of finely divided ferromagnetic metal powder, which is pyrophoric in air, is effected after reduction to the metal by (a) holding the mass of powder in movement in a vessel in the absence of O2 and H2 and cooling from at least 300 degrees C to the working temp. (b) introducing a limited amount of O2, opt. mixed with an inert gas, into the vessel while discharging heat, so that the temp. of the moving mass rises by is not >30 degrees C above the initial working temp, this gas being introduced into the mass until no more heat is developed (c) gradually increasing the temp. of the mass to 50-150 degrees C, and (d) making the oxygen content of the gas mixt. in the vessel at least equal to that in the air. Used for treating powders of Fe, Co or Ni or alloys of these metals.
NL7018910A 1970-12-29 1970-12-29 Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually NL7018910A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
NL7018910A NL7018910A (en) 1970-12-29 1970-12-29 Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL7018910A NL7018910A (en) 1970-12-29 1970-12-29 Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually

Publications (1)

Publication Number Publication Date
NL7018910A true NL7018910A (en) 1972-07-03

Family

ID=19811907

Family Applications (1)

Application Number Title Priority Date Filing Date
NL7018910A NL7018910A (en) 1970-12-29 1970-12-29 Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually

Country Status (1)

Country Link
NL (1) NL7018910A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0063730A2 (en) * 1981-04-25 1982-11-03 BASF Aktiengesellschaft Process for stabilising pyrophoric acicular ferromagnetic metal particles essentially consisting of iron
US5199998A (en) * 1991-05-10 1993-04-06 Basf Aktiengesellschaft Stabilization of acicular, ferromagnetic metal powders essentially consisting of iron

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0063730A2 (en) * 1981-04-25 1982-11-03 BASF Aktiengesellschaft Process for stabilising pyrophoric acicular ferromagnetic metal particles essentially consisting of iron
EP0063730A3 (en) * 1981-04-25 1983-04-13 BASF Aktiengesellschaft Process for stabilising pyrophoric acicular ferromagnetic metal particles essentially consisting of iron
US5199998A (en) * 1991-05-10 1993-04-06 Basf Aktiengesellschaft Stabilization of acicular, ferromagnetic metal powders essentially consisting of iron

Similar Documents

Publication Publication Date Title
GB901917A (en) Continuous process for foaming metal
JPS5655503A (en) Production of metal magnetic powder of superior corrosion resistance
NL7018910A (en) Passivating ferromagnetic powder - by treating cooled moving powder with limited amount of oxygen at controlled temp and gradually
GB1198650A (en) Passivation of Ferrous Metals.
US2395458A (en) Method of treating molten metals
GB1288133A (en)
GB1036635A (en) Beryllium copper based alloys and method of producing green compacts and sintered articles therefrom
GB1127221A (en) Prevention of hydrogen embrittlement in oxygen-bearing copper
FR2078508A5 (en) Multi component metal powder - by atomisation of soln, drying and reduction of solid particles
SU135222A1 (en) Method of making copper or silver alloys with 0.1-30% cadmium by metal-ceramic method
SU398636A1 (en) METHOD OF REFINING SILICON ALLOYS
GB1511667A (en) Powder metallurgical process for making precision components
JPS52111408A (en) Iron ore sintered pellet
JPS5562105A (en) Production of magnetic alloy powder
FR2218935A1 (en) Reducing nitrogen content of a gas - using refractory oxide, nickel and copper catalyst
GB770906A (en) Improvements in or relating to the heat treatment of metals and alloys
JPS5220909A (en) Composition of carbon containing metal oxide and iron-base alloy
GB1038111A (en) Process for the manufacture of an alloy
FR2041076A1 (en) Submicroscopic metallic particles in the - form of needles and capable of being perm
JPS55161001A (en) Production of steel powder for powder metallurgy
ES363201A1 (en) Steel refining procedure. (Machine-translation by Google Translate, not legally binding)
JPS54124814A (en) Additive for metallurgy and its manufacture
Rashev et al. Study of the Solubility of Nitrogen in Molten Metals Under Pressure
GB981712A (en) Improvements relating to the manufacture of silicon steel
GB1004605A (en) Improvements in or relating to processes for the manufacture of ductile metals in a finely-divided form