US4047982A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Permanent magnet and process for producing the same
Assignee: Fujitsu Ltd
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Filing: 1976-07-08
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Granted: 1977-09-13
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Expires: 1996-07-08
Abstract
Abstract The brittle nature and magnetic properties of the rare earth cobalt magnet are improved by the simultaneous addition of Cu and V. Cu and V are included in amounts of from 0.5 to 6% by weight and from 7 to 19% by weight, respectively. The simultaneous addition enables the rear earth cobalt magnet to be cast in the form of an article. In addition, the simultaneous addition not only improves the mechanical properties of the sintered article, in which form the conventional magnet was available, but also the magnetic properties, such that, for example, the coercive force is increased when the molar ratio of cobalt with respect to rear earth elements is great.
Inventors
- 👤 Masato Sagawa
- 👤 Takeaki Sakai
- 👤 Tatsuji Sasaki
- 👤 Zenzo Henmi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:07
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055; H01F1/0555; H01F1/0557
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
78 words
In a permanent magnet of an RCo type, wherein the R component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising replacing a part of said Co component with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight, respectively, based on said components R and Co.
Claim 2
Dependent Claim
78 words
In a permanent magnet of an RCo type, wherein the R component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising replacing a part of said Co component with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight, respectively, based on said components R and Co.
Claim 3
Dependent Claim
21 words
A permanent magnet according to claim 1, wherein said rare earth elements, consist of a group of samarium, cerium and praseodymium.
Claim 4
Dependent Claim
13 words
A permanent magnet according to claim 2, wherein said R component is samarium.
Claim 5
Dependent Claim
13 words
A permanent magnet according to claim 2, wherein said R component is cerium.
Claim 6
Dependent Claim
15 words
A permanent magnet according to claim 2, wherein said R component is samarium and cerium.
Claim 7
Dependent Claim
15 words
A permanent magnet according to claim 2, wherein said R component is samarium and praseodymium.
Claim 8
Dependent Claim
29 words
A permanent magnet according to claim 1, wherein said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 9
Dependent Claim
21 words
A permanent magnet according to claim 7, wherein said rare earth elements consist of a group of samarium, cerium and praseodymium.
Claim 10
Dependent Claim
13 words
A permanent magnet according to claim 8, wherein said R component is samarium.
Claim 11
Dependent Claim
12 words
A permanent magnet according to claim 8, wherein said component is cerium.
Claim 12
Dependent Claim
15 words
A permanent magnet according to claim 8, wherein said R component is samarium and cerium.
Claim 13
Dependent Claim
15 words
A permanent magnet according to claim 8, wherein said R component is samarium and praseodymium.
Claim 14
Dependent Claim
38 words
A permanent magnet according to claim 1, wherein said molar ratio is from 1:7.2 to 1:8.5, and said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 15
Dependent Claim
21 words
A permanent magnet according to claim 13, wherein said rare earth elements consist of a group of samarium, cerium and praseodymium.
Claim 16
Dependent Claim
13 words
A permanent magnet according to claim 14, wherein said R component is samarium.
Claim 17
Dependent Claim
12 words
A permanent magnet according to claim 15, wherein said component is cerium.
Claim 18
Dependent Claim
15 words
A permanent magnet according to claim 16, wherein said R component is samarium and cerium.
Claim 19
Dependent Claim
15 words
A permanent magnet according to claim 17, wherein said R component is samarium and praseodymium.
Claim 20
Dependent Claim
109 words
In a process for producing a permanent magnet of an RCo type, wherein the component R is one or more rare earth elements and the component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising adding vanadium and copper to said components R and Co and melting the resultant mixture, wherein a part of said Co component is replaced with both vanadium and copper in a manner such that said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 21
Dependent Claim
109 words
In a process for producing a permanent magnet of an RCo type, wherein the component R is one or more rare earth elements and the component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising adding vanadium and copper to said components R and Co and melting the resultant mixture, wherein a part of said Co component is replaced with both vanadium and copper in a manner such that said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 22
Dependent Claim
139 words
In a process for producing a permanent magnet of an RCo type, wherein the component R is one or more rare earth elements and the component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising adding vanadium and copper to said components R and Co, melting the resultant mixture, wherein a part of said Co component is replaced with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight and from 7 to 19% by weight, respectively, based on said components R and Co, solidifying the obtained melt in a vessel, through which the heat is withdrawn in a predetermined direction and solution-treating and ageing the solidified melt.
Claim 23
Dependent Claim
139 words
In a process for producing a permanent magnet of an RCo type, wherein the component R is one or more rare earth elements and the component Co is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, an improvement comprising adding vanadium and copper to said components R and Co, melting the resultant mixture, wherein a part of said Co component is replaced with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight and from 7 to 19% by weight, respectively, based on said components R and Co, solidifying the obtained melt in a vessel, through which the heat is withdrawn in a predetermined direction and solution-treating and ageing the solidified melt.
Claim 24
Dependent Claim
35 words
A process according to claim 20, wherein said solution treatment is performed at a temperature of from 1150° to 1210° C, and said ageing is performed at a temperature of from 700° to 820° C.
Claim 25
Dependent Claim
28 words
A process according to claim 20, wherein said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 26
Dependent Claim
35 words
A process according to claim 22, wherein said solution treatment is performed at a temperature of from 1150° to 1210° C, and said ageing is performed at a temperature of from 700° to 820° C.
Claim 27
Dependent Claim
117 words
In a process for producing a permanent magnet of a RCo type, wherein the R component is one or more rare earth elements and the Co component is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, said process comprising the steps of pressing a powder consisting of said components, and sintering said pressed powder, an improvement comprising replacing a part of said Co component with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight and from 7 to 19% by weight, respectively, based on said components R and Co.
Claim 28
Dependent Claim
117 words
In a process for producing a permanent magnet of a RCo type, wherein the R component is one or more rare earth elements and the Co component is cobalt or both cobalt and iron, and the molar ratio of said R component to said Co component is from 1:5 to 1:8.5, said process comprising the steps of pressing a powder consisting of said components, and sintering said pressed powder, an improvement comprising replacing a part of said Co component with both vanadium and copper, in a manner such that said vanadium and said copper are included from 0.5 to 6% by weight and from 7 to 19% by weight, respectively, based on said components R and Co.
Claim 29
Dependent Claim
75 words
A process according to claim 24, wherein said pressing is performed at a pressure of 2 to 5 ton/cm 2 , which a magnetic field is applied to the powder being pressed, said sintering is performed at a temperature from 1150° C to 1210° C under vacuum, said solution treatment is performed at a temperature of from 1150° to 1210° C, and said ageing is performed at a temperature of from 700° to 820° C.
Claim 30
Dependent Claim
37 words
A process according to claim 25, wherein said sintering, and heating at the solution temperature are simultaneous by performed, and immediately after the heating the sintered article is rapidly cooled from said solution temperature to room temperature.
Claim 31
Dependent Claim
28 words
A process according to claim 24, wherein said vanadium and said copper are included from 0.5 to 3% by weight and from 9 to 15% by weight, respectively.
Claim 32
Dependent Claim
75 words
A process according to claim 27, wherein said pressing is performed at a pressure of 2 to 5 ton/cm 2 , while a magnetic filed is applied to the powder being pressed, said sintering is performed at a temperature from 1150° C to 1210° C under vacuum, said solution treatment is performed at a temperature of from 1150° to 1210° C, and said ageing is performed at a temperature of from 700° to 820° C.
Claim 33
Dependent Claim
36 words
A process according to claim 28, wherein said sintering and heating at the solution temperature are simultaneously performed, and immediately after the heating the sintered article is rapidly cooled from said solution temperature to room temperature.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-12 | 1981-03-14 | 1981-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-12 | 1985-03-14 | 1985-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-12 | 1989-03-14 | 1989-09-13 | $7700.00 | Window Closed / Lapsed |