JPH0626011B2 - Magnetic disk substrate - Google Patents
Magnetic disk substrateInfo
- Publication number
- JPH0626011B2 JPH0626011B2 JP23091086A JP23091086A JPH0626011B2 JP H0626011 B2 JPH0626011 B2 JP H0626011B2 JP 23091086 A JP23091086 A JP 23091086A JP 23091086 A JP23091086 A JP 23091086A JP H0626011 B2 JPH0626011 B2 JP H0626011B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic disk
- disk substrate
- nickel
- magnetic
- glass
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000758 substrate Substances 0.000 title claims description 16
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 24
- 239000000463 material Substances 0.000 claims description 12
- 229910052759 nickel Inorganic materials 0.000 claims description 12
- 239000011521 glass Substances 0.000 claims description 10
- 229910000838 Al alloy Inorganic materials 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 6
- 239000010949 copper Substances 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 5
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 239000010936 titanium Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- 229910000990 Ni alloy Inorganic materials 0.000 claims description 3
- 239000000919 ceramic Substances 0.000 claims description 3
- 229910001000 nickel titanium Inorganic materials 0.000 claims description 2
- 229910000881 Cu alloy Inorganic materials 0.000 claims 1
- 239000010408 film Substances 0.000 description 14
- 239000002344 surface layer Substances 0.000 description 10
- 239000010410 layer Substances 0.000 description 8
- 238000004544 sputter deposition Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 6
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 238000005304 joining Methods 0.000 description 4
- 238000005336 cracking Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000007747 plating Methods 0.000 description 3
- 230000003746 surface roughness Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical group [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005496 eutectics Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- 238000005498 polishing Methods 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000005388 borosilicate glass Substances 0.000 description 1
- 238000005219 brazing Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 231100000989 no adverse effect Toxicity 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000005361 soda-lime glass Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Laminated Bodies (AREA)
- Magnetic Record Carriers (AREA)
Description
【発明の詳細な説明】 〈技術分野〉 本発明は記憶媒体として用いられる磁気ディスクのため
の基板に関する。Description: TECHNICAL FIELD The present invention relates to a substrate for a magnetic disk used as a storage medium.
〈従来の技術〉 高密度記録用の薄膜タイプの磁気ディスクの基板は、そ
の取扱いの便宜のために十分な強度が必要であり、磁気
媒体をスパッタリングで成形する場合には温度上昇に耐
え得るような耐熱性を備え、高密度の磁気記録を可能に
しかつ磁気ヘッドの摺接に対する所要の耐摩耗性を確保
するように高い表面精度及び十分な硬度を有する必要が
ある。<Prior Art> The substrate of a thin-film magnetic disk for high-density recording must have sufficient strength for convenience of handling, and should be able to withstand a temperature rise when forming a magnetic medium by sputtering. It is necessary to have high heat resistance and high surface accuracy and sufficient hardness so as to enable high-density magnetic recording and to secure required abrasion resistance against sliding contact of the magnetic head.
従来は、第２図に示されたように、アルミ合金からなる
薄板のブランクの両面を表面研磨し、研磨された面に無
電解ニッケルめっきを行ったり、アルマイト被膜処理を
行なうことにより表面層５を形成し、更にこの表面層の
表面を研磨することにより、その表面にクロム、鉄、ニ
ッケル、コバルトなどからなる磁気膜を塗布、めっきス
パッタリングなどにより形成し、更にその表面に保護膜
を形成して磁気ディスクを完成するようにしていた。Conventionally, as shown in FIG. 2, both surfaces of a thin blank made of an aluminum alloy are surface-polished, and the polished surfaces are subjected to electroless nickel plating or alumite coating treatment to form a surface layer 5 And then polishing the surface of this surface layer to apply a magnetic film of chromium, iron, nickel, cobalt, etc. to the surface, to form by sputtering, and to form a protective film on the surface. I was trying to complete a magnetic disk.
しかるに、このような表面層５を良好に形成するために
は、アルミ芯板１の表面粗さが０．０１５μｍ程度の高
い精度を有するものであることが必要となり、特に非金
属介在物を含まない高価なアルミ合金素材を必要とし、
またアルミ合金が比較的軟質であるためにその表面加工
が困難であり、磁気ディスク基板のコストアップの原因
となっていた。また無電解ニッケルめっき層は、厚さが
１０〜２０μｍ程度であるために強度が必ずしも十分で
なく、また２５０℃付近で磁気変態を起し、そのために
磁気膜をスパッタリングで成形する場合には基板表面の
温度上昇に伴い磁気特性の劣化を生じたり、或いはその
ために温度上昇を抑えた特殊なスパッタリング工程が必
要となり、製造工程に多大な時間を要する原因となって
いた。更に、アルマイト処理を行なった場合には、十分
な強度が得られるように表面層の厚さを十分大きくした
場合には、表面にボア等の欠陥を生じ易くなる。また、
研磨過程が２回必要であるために製造コストが高騰し、
製造に多大な時間が必要となる。However, in order to satisfactorily form such a surface layer 5, it is necessary that the surface roughness of the aluminum core plate 1 has a high accuracy of about 0.015 μm, and in particular, non-metallic inclusions are included. Requires no expensive aluminum alloy material,
Further, since the aluminum alloy is relatively soft, it is difficult to process the surface thereof, which causes a cost increase of the magnetic disk substrate. In addition, the electroless nickel plating layer is not necessarily sufficient in strength because it has a thickness of about 10 to 20 μm, and magnetic transformation occurs at around 250 ° C. Therefore, when the magnetic film is formed by sputtering, the substrate is As the surface temperature rises, the magnetic properties deteriorate, or a special sputtering process that suppresses the temperature rise is required for that purpose, which causes a large amount of time in the manufacturing process. Further, when the alumite treatment is performed, if the thickness of the surface layer is made sufficiently large so that sufficient strength can be obtained, defects such as bores are likely to occur on the surface. Also,
Since the polishing process is required twice, the manufacturing cost rises,
Manufacturing requires a lot of time.
そこで、特公昭５３−３７２０２号公報に開示されてい
るように、アルミニウムからなる芯板の表面にスパッタ
リングによりセラミックス材料の微粉末を付着させて硬
質の表面層を形成することが提案されている。しかしな
がら、表面層をスパッタリング或いは蒸着により形成す
る場合、被膜の形成に時間を要し、熱が放散するため
に、被膜の厚さを約１μｍ以上にすることが困難であ
る。硬質被膜が薄い場合には、磁気ディスクの強度が不
十分となり磁気ヘッドと接触した際の強度不速を生じた
り磁気ディスクを例えば床に落した場合に破損するなど
取扱い上の問題が発生し易い。Therefore, as disclosed in Japanese Patent Publication No. 53-37202, it has been proposed to deposit a fine powder of a ceramic material on the surface of a core plate made of aluminum by sputtering to form a hard surface layer. However, when the surface layer is formed by sputtering or vapor deposition, it takes time to form the coating film, and heat is dissipated. Therefore, it is difficult to make the coating film thickness about 1 μm or more. If the hard coating is thin, the strength of the magnetic disk becomes insufficient and the strength of the magnetic disk may become inadequate when it comes into contact with the magnetic head, or the magnetic disk may be damaged when dropped on the floor, for example. .
〈発明が解決しようとする問題点〉 このような従来技術の問題点に鑑み、本発明の主な目的
は、磁気ディスク基板として必要な強度、耐熱性、表面
精度及び表面硬度を有する改良された磁気ディスク用基
板を提供することにある。<Problems to be Solved by the Invention> In view of the problems of the prior art, the main object of the present invention is to improve the strength, heat resistance, surface accuracy and surface hardness required for a magnetic disk substrate. It is to provide a substrate for a magnetic disk.
〈問題点を解決するための手段〉 このような目的は、本発明によれば、磁気ディスク基板
であって、アルミニウムまたはアルミニウム合金からな
る芯板と、インサート材層と、ニッケル、チタン、ニッ
ケル合金またはチタン合金層と、ガラスまたはセラミッ
ク層とをこの順序にて積層してなることを特徴とする磁
気ディスク基板を提供することにより達成される。<Means for Solving Problems> According to the present invention, such a purpose is a magnetic disk substrate, which includes a core plate made of aluminum or an aluminum alloy, an insert material layer, nickel, titanium, and a nickel alloy. Alternatively, it can be achieved by providing a magnetic disk substrate characterized by laminating a titanium alloy layer and a glass or ceramic layer in this order.
〈作用〉 このように表面硬化層としてセラミック或いはガラス層
を用いることにより、十分な強度、耐熱性、緻密性及び
硬度が得られる。特に、ニッケル、チタン或いはこれら
の合金はガラス系材料に対する付着性が良く、また圧接
過程をインサート材と芯板との間の共晶温度より高くし
かも芯板の溶融点或いは表面層の軟化点以下の温度によ
り行なうことにより、芯板とインサート材との間の接合
力を確保することができる。<Operation> By using the ceramic or glass layer as the surface hardened layer in this manner, sufficient strength, heat resistance, compactness and hardness can be obtained. In particular, nickel, titanium or their alloys have good adhesion to glass-based materials, and the pressure welding process is higher than the eutectic temperature between the insert material and the core plate and is not higher than the melting point of the core plate or the softening point of the surface layer. By performing the heating at the temperature of 1, the joining force between the core plate and the insert material can be secured.
〈実施例〉 以下、本発明の好適実施例を添付の図面について詳しく
説明する。<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
第１図は本発明に基づく磁気ディスク基板の断面図であ
る。まず比較的安価なアルミ合金もしくは純アルミニウ
ムからなる芯板１を準備するが、従来技術に基づく場合
と異なり、その表面粗さが比較的問題とならない。次
に、厚さが約５０μｍ〜５００μｍのソーダ石灰ガラス
からなるガラス薄板２の片面にニッケル膜３をＰＶＤ
（物理的蒸着）或いはめっきなどにより０．５μｍ〜２
０μｍの厚さに成膜する。薄板２は、アルミナ、ジルコ
ニア、炭化硅素、窒化硅素などのセラミックス材料或い
は石英ガラス、硼硅酸ガラスなどのガラス質材料からな
るものであって良く、ニッケル膜３は、チタン、ニッケ
ル合金またはチタン合金からなるものであっても良い。
次に、ニッケル膜３と芯板１の表面との間に０．５μｍ
〜１００μｍの厚さのインサート材としての銅薄板４を
挾設し、５４８℃〜６３０℃の温度にて互いに圧接す
る。FIG. 1 is a sectional view of a magnetic disk substrate according to the present invention. First, the core plate 1 made of a relatively inexpensive aluminum alloy or pure aluminum is prepared, but unlike the case of the prior art, the surface roughness thereof does not pose a problem. Next, the nickel film 3 is PVD-coated on one surface of the glass thin plate 2 made of soda-lime glass having a thickness of about 50 μm to 500 μm.
0.5 μm to 2 by (physical vapor deposition) or plating
A film is formed to a thickness of 0 μm. The thin plate 2 may be made of a ceramic material such as alumina, zirconia, silicon carbide or silicon nitride, or a glassy material such as quartz glass or borosilicate glass, and the nickel film 3 may be made of titanium, nickel alloy or titanium alloy. It may consist of
Next, the gap between the nickel film 3 and the surface of the core plate 1 is 0.5 μm.
A copper thin plate 4 as an insert material having a thickness of ˜100 μm is sandwiched and pressed against each other at a temperature of 548 ° C. to 630 ° C.
このようにして得られた磁気ディスク基板は、３５０℃
の温度にて磁気膜をスパッタリングする場合でも何ら悪
影響を受けることがない。また、４００℃に加熱してこ
れを水中に没入させる急冷過程を５サイクル繰返して
も、割れや変形などの異常を生じることがなかった。ま
た、ガラス薄板２の面取りを行なったサンプルについ
て、約１メートルの高さから塩化ビニールタイル上に落
した場合にも破損や割れが生じなかった。また、このよ
うなサンプルにより割れ試験を行なった所、ガラス層の
割れが発生した場合でも、接合面が剥離することがな
く、十分な接合強度が得られていることが見出された。The magnetic disk substrate thus obtained has a temperature of 350 ° C.
Even when the magnetic film is sputtered at the above temperature, there is no adverse effect. Further, even if the rapid cooling process of heating to 400 ° C. and immersing it in water was repeated 5 cycles, no abnormality such as cracking or deformation occurred. Further, regarding the sample obtained by chamfering the thin glass plate 2, no damage or cracking occurred even when it was dropped onto a vinyl chloride tile from a height of about 1 meter. In addition, when a cracking test was conducted on such a sample, it was found that even if a crack in the glass layer occurred, the bonding surface did not peel off and sufficient bonding strength was obtained.
インサート材としては銅が好適であるが、銅はガラスに
対する付着性が良くない。しかしながら、ニッケル、チ
タンなどはガラスに対する付着性が良い。インサート材
を用いない場合には、アルミニウム製の芯板１の表面に
Ａｌ２Ｏ３膜が形成され、ニッケル膜３との間の接合力
が問題となるが、銅薄板４からなるインサート材を用
い、しかも銅とアルミニウムとの間の共晶温度以上の温
度により圧接を行なうため、十分な接合が得られる。Copper is suitable as the insert material, but copper does not adhere well to glass. However, nickel, titanium, etc. have good adhesion to glass. When the insert material is not used, an Al 2 O 3 film is formed on the surface of the aluminum core plate 1 and the bonding force with the nickel film 3 becomes a problem. Sufficient bonding can be obtained because the pressure welding is performed at a temperature above the eutectic temperature between copper and aluminum.
〈発明の効果〉 本発明の効果は以下の通りである。<Effects of the Invention> The effects of the present invention are as follows.
表面層が非磁性で硬質な材質からなり、その厚さも任
意に調節可能であるため、強度が高く緻密な表面層を得
ることができる。Since the surface layer is made of a non-magnetic and hard material and its thickness can be arbitrarily adjusted, it is possible to obtain a highly dense and dense surface layer.
表面の特性は接合された硬質層により得られるため、
芯板として用いられアルミ合金は安価な一般材で良くコ
スト低下が図れる。Since the surface properties are obtained by the joined hard layers,
The aluminum alloy used as the core plate is an inexpensive general material and the cost can be reduced.
接合前の芯板の表面粗さの影響は少なく、研磨が困難
なアルミ合金の表面研磨が必要なくなり、同じくコスト
低下が図れる。The influence of the surface roughness of the core plate before joining is small, and the surface polishing of the aluminum alloy, which is difficult to polish, is not necessary, and the cost can be similarly reduced.
接合方法を３００℃以上の耐熱性のある方法 （蝋付け、拡散接合など）とすれば、磁気膜をスパッタ
リング法により効率的に成膜することができ、磁気特性
の向上と生産性の向上が図れる。If the joining method is a method with heat resistance of 300 ° C. or higher (brazing, diffusion joining, etc.), the magnetic film can be formed efficiently by the sputtering method, which improves magnetic characteristics and productivity. Can be achieved.
第１図は本発明に基づく磁気ディスク基板の断面図であ
る。 第２図は従来形式の磁気ディスク基板の断面図である。 １……芯板、２……ガラス薄板 ３……ニッケル膜、４……銅薄板 ５……表面層FIG. 1 is a sectional view of a magnetic disk substrate according to the present invention. FIG. 2 is a sectional view of a conventional type magnetic disk substrate. 1 ... Core plate, 2 ... Glass thin plate, 3 ... Nickel film, 4 ... Copper thin plate, 5 ... Surface layer
Claims (2)
と、 ガラスまたはセラミック層とをこの順序にて積層してな
ることを特徴とする磁気ディスク基板。1. A magnetic disk substrate, comprising: a core plate made of aluminum or an aluminum alloy; an insert material layer; a nickel, titanium, nickel alloy or titanium alloy layer; and a glass or ceramic layer laminated in this order. A magnetic disk substrate characterized by being formed.
ることを特徴とする特許請求の範囲第１項に記載の磁気
ディスク基板。2. The magnetic disk substrate according to claim 1, wherein the insert material is made of copper or a copper alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23091086A JPH0626011B2 (en) | 1986-09-29 | 1986-09-29 | Magnetic disk substrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23091086A JPH0626011B2 (en) | 1986-09-29 | 1986-09-29 | Magnetic disk substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6386114A JPS6386114A (en) | 1988-04-16 |
| JPH0626011B2 true JPH0626011B2 (en) | 1994-04-06 |
Family
ID=16915198
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23091086A Expired - Lifetime JPH0626011B2 (en) | 1986-09-29 | 1986-09-29 | Magnetic disk substrate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0626011B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0992034A1 (en) * | 1997-06-18 | 2000-04-12 | The Dow Chemical Company | A multilayer hard drive disk and method to produce same |
-
1986
- 1986-09-29 JP JP23091086A patent/JPH0626011B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6386114A (en) | 1988-04-16 |
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