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US3989556A Expired / Lapsed US ⏱️ 0.0 years remaining

Semihard magnetic alloy and a process for the production thereof

Assignee: Proterial Ltd
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Filing: 1975-03-21
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Granted: 1976-11-02
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Expires: 1995-03-21
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Abstract

Abstract The semihard magnetic alloy of the present invention consists essentially of, by weight, 17 % to 45 % chromium, 3 % to 14 % cobalt, 0.2 % to 10 % titanium and balance substantially iron and has a residual magnetic flux density of 7,000 Gauss or more and a coercive force of 100 to 600 Oersted. Said alloy is produced by solution treating an alloy having the above-indicated composition at a temperature of 650° C to 1,200° C, and then either keeping the solution-treated alloy at a temperature of not higher than 650° C for a given period of time and repeatedly aging said alloy in multi-stage at gradually lowered temperatures, or cooling the solution-treated alloy continuously from a temperature of not higher than 700° C down to at least 550° C at a rate of not higher than 50° C per hour.

Inventors

  • 👤 Masao Iwata
  • 👤 Yoichi Ishijima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 06:31
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/30

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 52 words
A heat-treated magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted and consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight cobalt, 0.2 to 10% by weight titanium and a balance of substantially iron.
Claim 2
Dependent Claim 52 words
A heat-treated magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted and consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight cobalt, 0.2 to 10% by weight titanium and a balance of substantially iron.
Claim 3
Dependent Claim 35 words
The magnetic alloy according to claim 1 consisting essentially of 23 to 35% by weight chromium, 5 to 10% by weight cobalt, 0.3 to 3% by weight of titanium and a balance of substantially iron.
Claim 4
Dependent Claim 70 words
A heat-treated magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted and consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight cobalt, 0.2 to 10% by weight titanium and a balance of iron and up to 0.1% by weight carbon and up to 1% by weight calcium, magnesium, and manganese as impurities.
Claim 5
Dependent Claim 70 words
A heat-treated magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted and consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight cobalt, 0.2 to 10% by weight titanium and a balance of iron and up to 0.1% by weight carbon and up to 1% by weight calcium, magnesium, and manganese as impurities.
Claim 6
Dependent Claim 109 words
A process for producing a magnetic alloy having a residual magnetic flux of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted which comprises solution-treating an alloy consisting essentially of 17 to 45% by weight of chromium, 3 to 14% by weight of cobalt, 0.2 to 10% by weight of titanium and a balance of substantially iron at a temperature of 650° C. to 1,200° C., maintaining the solution-treated alloy at a temperature of not higher than 650° C. for a given period of time and then repeatedly aging said alloy in a multi-stage sequence at gradually lowered temperatures selected to yield said magnetic alloy.
Claim 7
Dependent Claim 109 words
A process for producing a magnetic alloy having a residual magnetic flux of 7,000 Gauss or more and a coersive force of 100 to 600 Oersted which comprises solution-treating an alloy consisting essentially of 17 to 45% by weight of chromium, 3 to 14% by weight of cobalt, 0.2 to 10% by weight of titanium and a balance of substantially iron at a temperature of 650° C. to 1,200° C., maintaining the solution-treated alloy at a temperature of not higher than 650° C. for a given period of time and then repeatedly aging said alloy in a multi-stage sequence at gradually lowered temperatures selected to yield said magnetic alloy.
Claim 8
Dependent Claim 42 words
The process according to claim 4, wherein the alloy which is solution-treated consists essentially of 23% to 35% by weight of chromium, 5 to 10% by weight of cobalt, 0.3 to 3% by weight of titanium and a balance of substantially iron.
Claim 9
Dependent Claim 20 words
The process according to claim 4, wherein said alloy is solution-treated at a temperature from 850° C. to 1,085° C.
Claim 10
Dependent Claim 63 words
The process according to claim 4, wherein the alloy is aged in a first stage at a temperature from 650° C. down to 600° C. for 0.1 to 5 hours and then in subsequent stages, each of which is at a temperature of 5° to 30° C. lower than that of the last preceding stage for 0.2 to 20 hours for each stage.
Claim 11
Dependent Claim 109 words
A process from producing a magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 150 to 600 Oersted which comprises solution-treating an alloy consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight of cobalt, 0.2 to 10% by weight of titanium and a balance of substantially iron at a temperature of 650° C. to 1,200° C. and then cooling the solution-treated alloy continuously from a temperature of not higher than 700° C. down to at least 550° C. at a rate of not higher than 50° C. per hour selected to yield said magnetic alloy.
Claim 12
Dependent Claim 109 words
A process from producing a magnetic alloy having a residual magnetic flux density of 7,000 Gauss or more and a coersive force of 150 to 600 Oersted which comprises solution-treating an alloy consisting essentially of 17 to 45% by weight chromium, 3 to 14% by weight of cobalt, 0.2 to 10% by weight of titanium and a balance of substantially iron at a temperature of 650° C. to 1,200° C. and then cooling the solution-treated alloy continuously from a temperature of not higher than 700° C. down to at least 550° C. at a rate of not higher than 50° C. per hour selected to yield said magnetic alloy.
Claim 13
Dependent Claim 40 words
The process according to claim 8, wherein the alloy which is solution-treated consists essentially of 23 to 35% by weight of chromium, 5 to 10% by weight cobalt, 0.3 to 3% by weight titanium and a balance of substantially iron.
Claim 14
Dependent Claim 21 words
The process according to claim 8, wherein said alloy is solution-treated at a temperature of from 850° C. to 1,085° C.
Claim 15
Dependent Claim 28 words
The process according to claim 8, wherein the alloy is continuously cooled from a temperature of from 700° C. to 580° C. down to at least 550° C.

References Cited (Backward Citations)

US1866925A Cited
US3806336A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-11-02 1980-05-03 1980-11-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-11-02 1984-05-03 1984-11-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-11-02 1988-05-03 1988-11-02 $7700.00 Window Closed / Lapsed

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