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US4859638A
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Magnetic head sliders, materials therefor, and the process for the production thereof
Assignee: Nippon Tungsten Co Ltd
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Filing: 1988-02-16
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Granted: 1989-08-22
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Expires: 2008-02-16
Abstract
Abstract A sintered material for recording/reading (particularly magnetic) head slider is produced by: preparing a powdery mixture which comprises 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, a garnet type compound consisting essentially of erbium oxide and aluminum oxide in amounts of 2 to 12% by weight and 0 (exclusive) to 2 (inclusive) % by weight based on the total composition, respectively, and expressed by the formula Er3(Al,Er)2(AlO4)3 through (Er,Al)3Al2(AlO4)3, and the balance being silicon carbide powder: the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs; and sintering the resultant mass under the application of a high pressure. Further sintering aids of Be, BeO, B and B4C may be present. For the garnet type compound, erbium oxide may be used, preferably in combination with alumina.
Inventors
- 👤 Toshiaki Wada
- 👤 Yoshiaki Katsuyama
- 👤 Mitsuhiko Furukawa
- 👤 Takashi Kitahira
- 👤 Michito Miyahara
- 👤 Kiyohito Misumi
- 👤 Masaharu Shiroyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:06
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/10; C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/515; C04B35/56; C04B35/565; C04B35/575; G11B5/127; G11B5/31; G11B5/3103; G11B5/3106
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
75 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 5 to 15% by weight of erbium oxide, and the balance being silicon carbide: the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 2
Dependent Claim
75 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 5 to 15% by weight of erbium oxide, and the balance being silicon carbide: the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 3
Dependent Claim
115 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 5 to 15% by weight of erbium oxide, a further sintering aid consisting of at least one of Be, BeO, B, B 4 C, Al, AlN and Al 2 O 3 in an amount of 0 (exclusive) to 2 (inclusive) % by weight based on the total composition, and the balance being silicon carbide: the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 4
Dependent Claim
115 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 5 to 15% by weight of erbium oxide, a further sintering aid consisting of at least one of Be, BeO, B, B 4 C, Al, AlN and Al 2 O 3 in an amount of 0 (exclusive) to 2 (inclusive) % by weight based on the total composition, and the balance being silicon carbide: the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 5
Dependent Claim
124 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 2 to 12% by weight of erbium oxide, 0 (exclusive) to 2 (inclusive) % by weight of aluminum oxide, and the balance being silicon carbide, wherein said erbium oxide and aluminum oxide are present as a compound of garnet crystal structure expressed by the formula Er 3 (Al,Er) 2 (AlO 4 ) 3 through (Er,Al) 3 Al 2 (AlO 4 ) 3 : the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 6
Dependent Claim
124 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 2 to 12% by weight of erbium oxide, 0 (exclusive) to 2 (inclusive) % by weight of aluminum oxide, and the balance being silicon carbide, wherein said erbium oxide and aluminum oxide are present as a compound of garnet crystal structure expressed by the formula Er 3 (Al,Er) 2 (AlO 4 ) 3 through (Er,Al) 3 Al 2 (AlO 4 ) 3 : the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 7
Dependent Claim
152 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 2 to 12% by weight of erbium oxide, 0 (exclusive) to 2 (inclusive) % by weight of aluminum oxide, a further sintering aid consisting of at least one of Be, BeO, B and B 4 C in an amount of 0 (exclusive) to 2 (inclusive) % by weight, and the balance being silicon carbide, wherein erbium oxide and aluminum oxide are present as a compound of garnet crystal structure expressed by the formula Er 3 (Al,Er) 2 (AlO 4 ) 3 through (Er,Al) 3 Al 2 (AlO 4 ) 3 : the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 8
Dependent Claim
152 words
A sintered material for recording/reading head slider consisting essentially of: 0.5 to 6.0% by weight of at least one component selected from the component group A consisting of the following elements and compounds thereof, 2 to 12% by weight of erbium oxide, 0 (exclusive) to 2 (inclusive) % by weight of aluminum oxide, a further sintering aid consisting of at least one of Be, BeO, B and B 4 C in an amount of 0 (exclusive) to 2 (inclusive) % by weight, and the balance being silicon carbide, wherein erbium oxide and aluminum oxide are present as a compound of garnet crystal structure expressed by the formula Er 3 (Al,Er) 2 (AlO 4 ) 3 through (Er,Al) 3 Al 2 (AlO 4 ) 3 : the elements for the component group A being Ti, V, Cr, Mn, Mg, Y, Zr, Nb, Mo, Ba, La, Ce, Gd, Hf, Ta, W, Th, and Cs.
Claim 9
Dependent Claim
32 words
A sintered material as defined in any of claim 1, 2, 3 or 4, wherein said compounds for the component group A are oxide, carbide, boride, nitride and a complex compound thereof.
Claim 10
Dependent Claim
126 words
A sintered material as defined in claim 5, wherein said component of the components group A is at least one selected from the group consisting of TiC, TiO 2 , TiN, VB 2 , VN, V 2 O 5 , Cr 3 C 2 , CrB, Cr 2 O 3 , MnO, Mn, Mg, MgO, Y, Y 2 O 3 , ZrC, ZrB 2 , ZrO 2 , NbC, NbB, NbN, Nb 2 O 3 , Mo 2 C, MoB, Mo, Ba, BaO, La 2 O 3 , La, CeB 6 , Ce 2 O, Gd 2 O 3 , HfC, HfB 2 , HfN, HfO 2 , TaC, TaB, TaN, Ta 2 O 5 , WC, WB, W, ThC, ThB 4 , ThN, and Cs.
Claim 11
Dependent Claim
22 words
A sintered material as defined in claim 3 or 4, wherein the compound of garnet crystal structure amounts to 4-10% by weight.
Claim 12
Dependent Claim
21 words
A sintered material as defined in claim 1 or 2, which includes substantially no pore having a diameter exceeding 2 microns.
Claim 13
Dependent Claim
21 words
A sintered material as defined in claim 3 or 4, which includes substantially no pore having a diameter exceeding one micron.
Claim 14
Dependent Claim
19 words
A sintered material as defined in claim 9, which includes substantially no pore having a diameter exceeding 0.5 micron.
Claim 15
Dependent Claim
25 words
A recording/reading head slider comprising a slider substrate member formed of the sintered material as defined in any of claim 1, 2, 3 or 4.
Claim 16
Dependent Claim
24 words
A recording/reading head slider compising a slider substrate member produced by the process as defined in any of claim 3, 4, 7 or 8.
References Cited (Backward Citations)
US4564490A
Cited
US4569921A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-21 | 1993-02-20 | 1993-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-21 | 1997-02-20 | 1997-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-21 | 2001-02-20 | 2001-08-22 | $7700.00 | Window Closed / Lapsed |