US4923533A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic shield-forming magnetically soft powder, composition thereof, and process of making
Assignee: TDK Corp
•
Filing: 1988-07-29
•
Granted: 1990-05-08
•
Expires: 2008-07-29
Abstract
Abstract A powder comprising flakes of magnetically soft amorphous alloy having an average thickness of 0.01-1 μm and an aspect ratio of 10-10,000 is blended with a binder to form a coating composition from which a magnetic shield is fabricated. The alloy is basically an Fe-B-Si ternary alloy in which iron may be partially replaced by another metal.
Inventors
- 👤 Masao Shigeta
- 👤 Tsutomu Choh
- 👤 Hiroyoshi Shimizu
- 👤 Ippo Hirai
- 👤 Shohei Mimura
- 👤 Atsushi Makimura
- 👤 Hiroshi Hosaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:04
CPC Classifications
H; H05; H05K; H05K9/00; H05K9/0073; H05K9/0081; H05K9/0083; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/147; H01F1/153; H01F1/15341; H01F1/1535; H01F1/15358; H01F1/15366; H01F1/15375; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/1216; Y10T428/12167
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
112 words
A powder suitable for forming a magnetic shield, comprising: flakes of magnetically soft amorphous alloy having an average thickness of from about 0.01 to about 1 μm and an aspect ratio, defined as average outer diameter divided by average thickness of from about 10 to about 10,000, said soft amorphous alloy being an alloy of a ternary composition having the formula: Fe.sub.u M.sub.v (Si,B).sub.w wherein M is at least one metal selected from the group consisting of Cr, Nb, Ti, V, Ta, Mo, W, Mn, Co, and Ni; u, v and w are the atom percentages of Fe, M and Si+B, respectively, and are v=0 to 10, w=15 to 38 and u=100-v-w.
Claim 2
Dependent Claim
112 words
A powder suitable for forming a magnetic shield, comprising: flakes of magnetically soft amorphous alloy having an average thickness of from about 0.01 to about 1 μm and an aspect ratio, defined as average outer diameter divided by average thickness of from about 10 to about 10,000, said soft amorphous alloy being an alloy of a ternary composition having the formula: Fe.sub.u M.sub.v (Si,B).sub.w wherein M is at least one metal selected from the group consisting of Cr, Nb, Ti, V, Ta, Mo, W, Mn, Co, and Ni; u, v and w are the atom percentages of Fe, M and Si+B, respectively, and are v=0 to 10, w=15 to 38 and u=100-v-w.
Claim 3
Dependent Claim
34 words
The powder of claim 1, wherein said flakes have a major axis to minor axis ratio of at least about 1.2 and exhibit a contour having major and minor axes in a projected plane.
Claim 4
Dependent Claim
70 words
The powder of claim 1, wherein the alloy has a composition which falls within the polygon described by points A through H in the ternary composition diagram of FIG. 1 where each coordinate point is as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 5
Dependent Claim
20 words
The powder of claim 1 wherein the alloy consists essentially of three elements: iron Fe, boron B, and silicon Si.
Claim 6
Dependent Claim
86 words
The powder of claim 4, wherein the alloy has a composition defined by points A through H, as these points represent a polygon, in the ternary composition diagram of FIG. 1, where each coordinate point is defined by the atom percents of Fe, B and Si and each point is defined as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 7
Dependent Claim
19 words
The powder of claim 4 wherein the boron is partially replaced by at least one of phosphorus and carbon.
Claim 8
Dependent Claim
20 words
The powder of claim 1 wherein M is chromium Cr and v is a positive number of more than 0.
Claim 9
Dependent Claim
15 words
The powder of claim 7 wherein v is a positive number of 2 to 10.
Claim 10
Dependent Claim
26 words
The powder of claim 1 wherein M is a mixture of chromium Cr and niobium Nb and v is a positive number of more than 0.
Claim 11
Dependent Claim
37 words
The powder of claim 9 wherein about 2 to about 9 atom % of chromium and about 1 to about 8 atom % of niobium are present and v is a positive number of 3 to 10.
Claim 12
Dependent Claim
33 words
The powder of claim 1 wherein M is a mixture of chromium Cr and at least one of molybdenum Mo and nickel Ni and v is a positive number of more than 0.
Claim 13
Dependent Claim
24 words
The powder of any one of claims 7 to 11 wherein the boron is partially replaced by at least one of phosphorus and carbon.
Claim 14
Dependent Claim
88 words
The powder of any one of claims 7-11, wherein the alloy has a composition defined by the coordinate points A through H, in the ternary composition diagram of FIG. 1, wherein each coordinate point is defined by the atom percents of Fe +M, B and Si and points A through H are defined as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 15
Dependent Claim
16 words
The powder of claim 1 which has a maximum magnetic permeability of at least about 20.
Claim 16
Dependent Claim
69 words
The powder of claim 1 which comprises at least 35% by weight of magnetically soft amorphous alloy flakes having a particle size of from 10 to 50 μm, up to 0.5% by weight of magnetically soft amorphous alloy flakes having a particle size of more than 88 μm, and up to 10% by weight of magnetically soft amorphous alloy flakes having a particle size of less than 3 μm.
Claim 17
Dependent Claim
115 words
A magnetically shielding composition, comprising: a powder of flakes of magnetically soft amorphous alloy with the flakes having an average thickness ranging from about 0.01 to about 1 μm and an aspect ratio, defined as average outer diameter divided by average thickness, of from about 10 to about 10,000, said soft amorphous alloy being of a ternary composition of the formula: Fe.sub.u M.sub.v (Si,B).sub.w wherein M is at least one metal selected from the group consisting of Cr, Nb, Ti, V, Ta, Mo, W, Mn, Co, and Ni; u, v and w are the atom percentages of Fe, M and Si+B, respectively, and are v=0 to 10, w=15 to 38 and u=100-v-w; and a binder.
Claim 18
Dependent Claim
115 words
A magnetically shielding composition, comprising: a powder of flakes of magnetically soft amorphous alloy with the flakes having an average thickness ranging from about 0.01 to about 1 μm and an aspect ratio, defined as average outer diameter divided by average thickness, of from about 10 to about 10,000, said soft amorphous alloy being of a ternary composition of the formula: Fe.sub.u M.sub.v (Si,B).sub.w wherein M is at least one metal selected from the group consisting of Cr, Nb, Ti, V, Ta, Mo, W, Mn, Co, and Ni; u, v and w are the atom percentages of Fe, M and Si+B, respectively, and are v=0 to 10, w=15 to 38 and u=100-v-w; and a binder.
Claim 19
Dependent Claim
34 words
The composition of claim 16, wherein said flakes have a major axis to minor axis ratio of at least about 1.2 and exhibit a contour having major and minor axes in a projected plane.
Claim 20
Dependent Claim
83 words
The composition of claim 16, wherein the alloy has a composition defined by the coordinate points A through H of the ternary composition diagram of FIG. 1, where each coordinate point is defined by the atom percents of Fe+M, B and Si and each coordinate point is defined as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 21
Dependent Claim
20 words
The composition of claim 16 wherein the alloy consists essentially of three elements: iron Fe, boron B, and silicon Si.
Claim 22
Dependent Claim
84 words
The composition of claim 19, wherein the alloy has a composition defined by the coordinate points A through H in the ternary composition diagram of FIG. 1, wherein each coordinate point is defined by the atom percentages of Fe, B and Si and where each coordinate point is defined as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 23
Dependent Claim
19 words
The composition of claim 19 wherein the boron is partially replaced by at least one of phosphorus and carbon.
Claim 24
Dependent Claim
20 words
The composition of claim 16 wherein M is chromium Cr and v is a positive number of more than 0.
Claim 25
Dependent Claim
15 words
The composition of claim 22 wherein v is a positive number of 2 to 10.
Claim 26
Dependent Claim
26 words
The composition of claim 16 wherein M is a mixture of chromium Cr and niobium Nb and v is a positive number of more than 0.
Claim 27
Dependent Claim
37 words
The composition of claim 24 wherein about 2 to about 9 atom % of chromium and about 1 to about 8 atom % of niobium are present and v is a positive number of 3 to 10.
Claim 28
Dependent Claim
33 words
The composition of claim 16 wherein M is a mixture of chromium Cr and at least one of molybdenum Mo and nickel Ni and v is a positive number of more than 0.
Claim 29
Dependent Claim
24 words
The composition of any one of claims 22 to 26 wherein the boron is partially replaced by at least one of phosphorus and carbon.
Claim 30
Dependent Claim
88 words
The composition of any one of claims 22 to 26, wherein the alloy has a composition defined by the coordinate points A through H in the ternary composition diagram of FIG. 1, wherein each coordinate point is defined by the atom percentages of Fe+M, B and Si and each coordinate point is defined as follows: A (63, 32, 5) B (62, 23, 15) C (63, 15, 22) D (68, 5, 27) E (80, 5, 15) F (77, 7, 16), G (75, 13, 12), and H (77, 18, 5).
Claim 31
Dependent Claim
17 words
The composition of claim 16 wherein the powder has a maximum magnetic permeability of at least 20.
Claim 32
Dependent Claim
71 words
The composition of claim 16 wherein the powder comprises: at least 35% by weight of magnetically soft amorphous alloy flakes having a particle size of from 10 to 50 μm, up to 0.5% by weight of magnetically soft amorphous alloy flakes having a particle size of more than 88 μm, and up to 10% by weight of magnetically soft amorphous alloy flakes having a particle size of less than 3 μm.
Claim 33
Dependent Claim
37 words
The composition of claim 16 which has a maximum magnetic permeability of about 15 to about 70 and a coercive force of from about 5 to about 20 Oe, as measured in a direct current magnetic field.
Claim 34
Dependent Claim
29 words
The composition of claim 16 which comprises 65 to 95% by weight of the magnetically soft amorphous alloy particle powder, and the binder is comprised of a urethane polymer.
Claim 35
Dependent Claim
13 words
The cured composition of claim 32 wherein the polyurethane binder has been thermoset.
Claim 36
Dependent Claim
30 words
The composition of claim 16 wherein the binder is a radiation-curable compound, and the powder and the binder are present in a volume ratio of about 2:8 to about 8:2.
Claim 37
Dependent Claim
14 words
The cured composition of claim 34 wherein the radiation-curable compound binder has been cured.
References Cited (Backward Citations)
JPS5859268A
Cited
JPS58197205A
Cited
JPS59201493A
Cited
JPS60401A
Cited
JPS6014081A
Cited
US4773931A
Cited
US4720411A
Cited
US4726990A
Cited
EP0239031A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-07 | 1993-11-06 | 1994-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-07 | 1997-11-06 | 1998-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-07 | 2001-11-06 | 2002-05-08 | $7700.00 | Window Closed / Lapsed |