Patent US5002728A successfully refreshed from Google Patents.
US5002728A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing soft magnetic Fe-Si alloy sintered product
Assignee: Sumitomo Metal Mining Co Ltd
•
Filing: 1989-12-18
•
Granted: 1991-03-26
•
Expires: 2009-12-18
Abstract
Abstract A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising a step of injection molding a composition comprising an Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder a step of applying binder-removal under heating to the resultant green body and applying a degassing and Si-diffusing; and a step of subsequently applying sintering. The sintered product is, preferably, applied with further heating for obtaining better soft magnetic property. Soft magnetic property of the sintered products is as comparable with or superior to products by conventional powder metallurgy.
Inventors
- 👤 Masakazu Achikita
- 👤 Shinichi Sogame
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:29
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/22; B22F3/225; C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/147; H01F1/14766; B22F2998/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
78 words
A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising: a step of injection molding a composition comprising an Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder; a step of applying a binder-removing treatment under heating to the resultant molding product and applying a degassing, treatment and an Si-diffusing treatment; and a step of subsequently applying a sintering treatment.
Claim 2
Independent Claim
78 words
A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising: a step of injection molding a composition comprising an Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder; a step of applying a binder-removing treatment under heating to the resultant molding product and applying a degassing, treatment and an Si-diffusing treatment; and a step of subsequently applying a sintering treatment.
Claim 3
Dependent Claim
23 words
A method as defined in claim 1, wherein the degassing treatment and the Si-diffusing treatment are applied after the binder-removing treatment under heating.
Claim 4
Dependent Claim
28 words
A method as defined in claim 1, wherein the Fe-Si powder mixture comprises an Fe powder and an Fe-Si alloy powder or two kinds of Fe-Si alloy powders.
Claim 5
Dependent Claim
62 words
A method as defined in claim 3, wherein one of the powders has a mean particle size of 4 to 10 μm and, the other of them has a mean particle size of from 20 to 50 μm, and wherein from 20 to 50% by weight of the former and 50 to 80% by weight of the later of them are blended.
Claim 6
Dependent Claim
33 words
A method as defined in claim 1, wherein from 60 to 80% by volume of the Fe-Si powder mixture and from 40 to 20% by volume of the binder are mixed and prepared.
Claim 7
Dependent Claim
28 words
A method as defined in claim 1, wherein the binder-removing treatment, the degasing treatment and the Si-diffusing treatment are conducted at a temperature from 500° to 900° C.
Claim 8
Dependent Claim
33 words
A method as defined in claim 1, wherein the sintering treatment is applied at a temperature from 1200° to 1350° C. in a hydrogen atmosphere or in vacuum for 30 to 180 min.
Claim 9
Independent Claim
93 words
A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising: a step of injection molding a composition comprising a Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder; a step of applying a binder-removing treatment under heating to the resultant molding product and applying a degasing treatment and a Si-diffusing treatment; a step of subsequently applying a sintering treatment, and a step of applying a heat treatment at a temperature from 800° to 1100° C.
Claim 10
Independent Claim
93 words
A method of manufacturing a soft magnetic Fe-Si alloy sintered product comprising: a step of injection molding a composition comprising a Fe-Si powder mixture blended so as to contain from 1 to 10% by weight of Si and the substantial balance of Fe and a binder; a step of applying a binder-removing treatment under heating to the resultant molding product and applying a degasing treatment and a Si-diffusing treatment; a step of subsequently applying a sintering treatment, and a step of applying a heat treatment at a temperature from 800° to 1100° C.
Claim 11
Dependent Claim
23 words
A method as defined in claim 8, wherein the degassing treatment and the Si-diffusing treatment are applied after the binder-removing treatment under heating.
Claim 12
Dependent Claim
28 words
A method as defined in claim 8, wherein the Fe-Si powder mixture comprises an Fe powder and an Fe-Si alloy powder or two kinds of Fe-Si alloy powders.
Claim 13
Dependent Claim
60 words
A method as defined in claim 8, wherein one of the powder has a mean particle size of 4 to 10 μm and, the other of them has a mean particle size of from 20 to 50 μm, and wherein from 20 to 50% by weight of the former and 50 to 80% by weight of the later are blended.
Claim 14
Dependent Claim
33 words
A method as defined in claim 10, wherein from 60 to 80% by volume of the Fe-Si powder mixture and from 40 to 20% by volume of the binder are mixed and prepared.
Claim 15
Dependent Claim
28 words
A method as defined in claim 10, wherein the binder-removing treatment, the degassing treatment and the Si-diffusing treatment are conducted at a temperature from 500° to 900° C.
Claim 16
Dependent Claim
33 words
A method as defined in claim 10, wherein the sintering treatment is applied at a temperature from 1200° to 1350° C. in a hydrogen atmosphere or in vacuum for 30 to 180 min.
Claim 17
Dependent Claim
32 words
A method of defined in claim 10, wherein the heat treatment is applied by maintaining the heating for 30 to 120 min under heating and, subsequently, gradually cooling down to 500° C.
References Cited (Backward Citations)
US4508567A
Cited
US4603062A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-03-25 | 1994-09-24 | 1995-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-25 | 1998-09-24 | 1999-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-25 | 2002-09-24 | 2003-03-26 | $7700.00 | Window Closed / Lapsed |