Patent US1638824A successfully refreshed from Google Patents.
EP0088992A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for manufacturing an object of soft-magnetic material by bonding together a mass of powder grains
Assignee: ABB Norden Holding AB
•
Filing: 1983-03-09
•
Granted: —
•
Expires: 2003-03-09
Abstract
Abstract A method for manufacturing an object of soft-magnetic material by bonding together a mass of powder grains of iron-based soft-magnetic material in the form of pure iron or in the form of iron containing silicon, aluminium and/or titanium. The grains are provided either with a coating (2) containing iron oxide chemically bonded to the grains and, at least in those cases where the iron-based material consists of pure iron, containing in addition thereto an oxide of silicon, aluminium and/or titanium, or the grains are provided with a coating (2) containing a reaction product of iron oxide, which oxide is chemically bonded to the grains, and an oxide of silicon, aluminium and/or titanium. The grains provided with said coating are subjected to an isostatic pressing at a temperature of at most 900°C and at a pressure necessary for forming a coherent, compact body of the powder mass. The coating preferably has a thickness of 0.01 - 0.5 µm.
Inventors
- 👤 Hans Dr.Ing. Larker
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 10:42
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; H01F1/24; B; B22; B22F; B22F1/00; B22F1/16; B22F3/00; B22F3/12; B22F3/14; B22F3/15; H01F1/33
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
166 words
1 . Method for manufacturing an object of soft-magnetic material by bonding together a mass of powder grains of an iron-based.soft-magnetic material in the form of at least approximately pure iron or in the form of iron containing silicon, aluminium and/or titanium, which grains are provided with a coating and are subjected to pressure and heating, characterized in that the coating of the grains (1) contains iron oxide, chemically bonded to the grains, and, at least in those cases where the iron- based material consists of at least approximately pure iron, contains in addition thereto an oxide of silicon, aluminium and/or titanium, or/and that the coating of the grains contains a reaction product of iron oxide, which oxide is chemically bonded to the grains, and an oxide of silicon, aluminium and/or titanium, and that the mass of coated grains is subjected to an isostatic pressing at a temperature of at most 900°C and at a pressure necessary for forming a coherent dense body of the mass.
Claim 2
Dependent Claim
166 words
1 . Method for manufacturing an object of soft-magnetic material by bonding together a mass of powder grains of an iron-based.soft-magnetic material in the form of at least approximately pure iron or in the form of iron containing silicon, aluminium and/or titanium, which grains are provided with a coating and are subjected to pressure and heating, characterized in that the coating of the grains (1) contains iron oxide, chemically bonded to the grains, and, at least in those cases where the iron- based material consists of at least approximately pure iron, contains in addition thereto an oxide of silicon, aluminium and/or titanium, or/and that the coating of the grains contains a reaction product of iron oxide, which oxide is chemically bonded to the grains, and an oxide of silicon, aluminium and/or titanium, and that the mass of coated grains is subjected to an isostatic pressing at a temperature of at most 900°C and at a pressure necessary for forming a coherent dense body of the mass.
Claim 3
Dependent Claim
21 words
Method according to claim 1, characterized in that the density of the compressed body exceeds 99 % of the theoretical density.
Claim 4
Dependent Claim
29 words
Method according to claim 1 or 2, characterized in that the coating has a thickness of 0.01 - 0.5 µm and the grains have a size of 50-1000 µm.
Claim 5
Dependent Claim
68 words
Method according to any of claim 1 - 3, characterized in that the iron-based material consists of at least approximately pure iron, and that the grains are provided with a coating consisting of a layer of iron oxide, formed on the grains by treating them in an oxidizing atmosphere, and of a layer of an oxide of silicon, aluminium, and/or titanium applied on the layer of iron oxide.
Claim 6
Dependent Claim
63 words
Method according to any of claim 1- 3, characterized in that the iron-based material consists of iron containing silicon, aluminium and/or titaizium, and that the grains are provided with a coating consisting of a reaction product of iron oxide, formed on the grains by treating them in an oxidizing atomosphere, and an oxide of silicon, aluminium and/or titanium included in the iron-based material.
Claim 7
Dependent Claim
32 words
Method according to any of claim 1 - 5, characterized in that the isostatic pressing is carried out at a temperature of 600-900°C and at a pressure of at least 10 MPa.
Claim 8
Dependent Claim
34 words
Method according to any of claim 1 - 5, characterized in that the isostatic pressing is carried out at a temperature of 600-775 0 C and at a pressure of at least 50 MPa.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.