JPH0233722A - Core slider for magnetic head - Google Patents
Core slider for magnetic headInfo
- Publication number
- JPH0233722A JPH0233722A JP18327988A JP18327988A JPH0233722A JP H0233722 A JPH0233722 A JP H0233722A JP 18327988 A JP18327988 A JP 18327988A JP 18327988 A JP18327988 A JP 18327988A JP H0233722 A JPH0233722 A JP H0233722A
- Authority
- JP
- Japan
- Prior art keywords
- sliders
- ferrite
- core
- machining
- magnetic
- 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.)
- Granted
Links
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 21
- 230000003746 surface roughness Effects 0.000 claims abstract description 5
- 238000009499 grossing Methods 0.000 abstract description 7
- 238000003754 machining Methods 0.000 abstract description 6
- 238000011282 treatment Methods 0.000 abstract description 5
- 230000007423 decrease Effects 0.000 abstract description 4
- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 abstract description 4
- 150000004649 carbonic acid derivatives Chemical class 0.000 abstract description 2
- 238000010438 heat treatment Methods 0.000 abstract description 2
- 239000011656 manganese carbonate Substances 0.000 abstract description 2
- 235000006748 manganese carbonate Nutrition 0.000 abstract description 2
- 229910000016 manganese(II) carbonate Inorganic materials 0.000 abstract description 2
- 239000000463 material Substances 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N zinc oxide Inorganic materials [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052751 metal Inorganic materials 0.000 abstract 1
- 239000002184 metal Substances 0.000 abstract 1
- 150000002739 metals Chemical class 0.000 abstract 1
- 239000000203 mixture Substances 0.000 abstract 1
- 238000005303 weighing Methods 0.000 abstract 1
- 229910003145 α-Fe2O3 Inorganic materials 0.000 abstract 1
- 238000000034 method Methods 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- 230000003068 static effect Effects 0.000 description 6
- 238000005498 polishing Methods 0.000 description 5
- 239000002344 surface layer Substances 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 239000006061 abrasive grain Substances 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- 238000005488 sandblasting Methods 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000003746 solid phase reaction Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Adjustment Of The Magnetic Head Position Track Following On Tapes (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、磁気ディスクに記録・再生を行うための浮
動式の磁気ヘッドに採用される磁気ヘッド用コアスライ
ダに関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a core slider for a magnetic head that is employed in a floating magnetic head for recording and reproducing data on and from a magnetic disk.
［従来の技術］
従来、浮動式磁気ヘットのコアスライダとして、Ｍｎ−
Ｚｎフェライト等の焼結フェライトを素材とするモノリ
シックタイプのものが用いられている。[Prior Art] Conventionally, Mn-
A monolithic type made of sintered ferrite such as Zn ferrite is used.
これは、第１図に示すように、いずれもフェライトを素
材とする０字コア１と平板状のスライダ２とかその間に
磁気ギャップ３を構成するようにカラス４で接合されて
いるもので、第２図及び第３図に示す方法で製造される
。すなわち、断面がＣ字状の第１コアブロツク５と平板
状の第２コアブロツク６とをカラス４を用いて接合して
一体化した後、第１コアブロツク５を所定のコア幅にな
るように切削し、ついて磁気ディスクに対向する面をラ
ップ研磨して平滑に仕」二げ、さらにこの面に浮動性を
向」ニさせるための溝７を加工し、ラップ加工してテー
パ部８を形成し、所定の寸法にチップスライスしてコア
スライダとする工程となる。As shown in Fig. 1, this consists of a zero-shaped core 1 made of ferrite, a flat slider 2, and a crow 4 that forms a magnetic gap 3 between them. It is manufactured by the method shown in FIGS. 2 and 3. That is, after a first core block 5 having a C-shaped cross section and a second core block 6 having a flat plate shape are joined and integrated using a crow 4, the first core block 5 is cut to have a predetermined core width. Then, the surface facing the magnetic disk is lapped to make it smooth, and a groove 7 is formed on this surface to improve the floating property, and a tapered part 8 is formed by lapping. This is the process of slicing the chip into predetermined dimensions to form a core slider.
このような磁気ヘット用コアスライダは、停止時におい
ては溝７側の面を磁気ディスクに接触させており、駆動
時にはディスク表面より０．２〜０ 、５１ｔ ｍ浮上
した状態で記録または再生を行う。When this type of core slider for a magnetic head is stopped, the surface on the groove 7 side is in contact with the magnetic disk, and when it is driven, it performs recording or reproduction while floating 0.2 to 0.51 tm above the disk surface. .
［発明か解決しようとする課題］
しかしながら、このような従来の磁気コアスライダにお
いては、表層部のフェライト粒子が脱落しやすく、この
脱落粒子が磁気記憶媒体である磁気ディスクに付着し、
磁気ヘットがこの脱落粒子に衝突してディスク表面の磁
性層を破壊４−るいわゆるヘノトクラッンコが起こりや
すくなる。[Problems to be Solved by the Invention] However, in such a conventional magnetic core slider, ferrite particles on the surface layer easily fall off, and these fallen particles adhere to the magnetic disk, which is a magnetic storage medium.
The magnetic head collides with these fallen particles and destroys the magnetic layer on the surface of the disk, which is likely to occur.
この脱落現象の原因として、フェライトはらともと粉体
を飼料として加熱や■−縮を行−で製造した成形体を機
械加］ニしたものであり、これらの機械加７［時にかな
りの粒子が脱落し一ζその隣接４ろ粒子が脱落しやすい
状態になっていること、この脱落傾向が、空気中の水分
の存在や表層近傍におＪる残留応力歪みによって加速さ
れることム゛とか考えられた。The reason for this falling-off phenomenon is that ferrite is a molded product produced by heating and shrinking the ferrite powder as feed, and these mechanical treatments sometimes result in a considerable amount of particles. It is thought that the neighboring particles are in a state where they are likely to fall off, and that this tendency to fall off is accelerated by the presence of moisture in the air and residual stress distortion near the surface layer. It was done.
［課題を解決するための手段１
」１記のような課題を解決するために、発明者゛らはフ
ェライトの脱粒の原因を突き止めるためのテストを行っ
た。[Means for solving the problem 1] In order to solve the problem as described in 1, the inventors conducted a test to find out the cause of ferrite shedding.
脱粒を加速する試験方法として、耐高温高湿試験を温度
４０〜８０℃−湿度５０％以トー保１′与時間５〜Ｉ
０００１−１ ｒの条件に設定して４ｉい、事前の処理
を変えたザンプルについて脱落１．に粒数を測定したと
ころ、このような条件下での試験にわいては、フェライ
ト脱粒は長時間継続的に発生ずることが判明し）こ。ま
た、脱落した微小なデツプはその大きさにかかわらずコ
アスライダ本体から離れた位置に飛散しており、脱落し
たチップの走査型電子顕微鏡観察においては、加工によ
る塑性流動面が多く発見されている。これらの事象はい
ずれら、時間の経過とと６に応力か解放されてマイクロ
クラックが進展することによって脱粒することを示して
おり、この現象か時間遅れ破壊または静的疲労破壊の典
型的な例であることが推定される。静的疲労破壊とは、
荷重がゆっくりと加えられたり、瞬間的破壊に必要な水
準以下の荷重が長時間加えられた場合に、飼料中に最初
から存在した欠陥か大きく成長し、本来の破壊強度より
はるかに低い荷重（応力）で破壊が起きるものである。As a test method for accelerating grain shedding, a high temperature and high humidity resistance test was carried out at a temperature of 40 to 80°C and a humidity of 50% or higher for a given time of 5 to 1.
0001-1 Dropout 1 for samples with 4i settings and pre-processing set to r conditions. When the number of grains was measured, it was found that ferrite grain shedding occurs continuously for a long time in tests under these conditions. In addition, regardless of their size, the dropped microscopic chips are scattered at a distance from the core slider body, and many plastic flow surfaces due to machining are found in scanning electron microscopy observations of dropped chips. . All of these events indicate that grains shed as stress is released over time and microcracks develop, and this phenomenon is a typical example of time-delayed fracture or static fatigue fracture. It is estimated that What is static fatigue failure?
If loads are applied slowly, or if loads below the level required for instantaneous failure are applied for long periods of time, any defects that were originally present in the feed may grow larger and cause loads that are much lower than their original failure strength ( Destruction occurs due to stress).
このような静的疲労破壊において、欠陥の進展は、化学
的作用による場合、機械的作用による場合、熱的作用に
よる場合等がある。このメカニズトを＝】アスライグの
場合に当てはめると、切削等の加工によりフェライト表
層に予測及びコントロールの困難なマイクロクラックが
発生し、こイ１か残留応力に、１って成長４′ろと考え
らイ１ろ。耐高〆ム１゜高湿試験では、マイク［ツクラ
ックの先端部の化学的に反応性の高い面にに水分が作用
し、）Ｊライト中のＦｅ−０−Ｆｅ結合を切るような加
水分解反応を惹起し、マイク〔ツクラックをさらに進展
さ■ると考えられる。In such static fatigue fracture, defects may develop due to chemical action, mechanical action, thermal action, etc. Applying this mechanism to the case of Aslig, microcracks that are difficult to predict and control occur on the ferrite surface layer due to processing such as cutting, resulting in growth of 4' due to residual stress. I1ro. In the high-temperature 1° high-humidity test, water acts on the chemically reactive surface of the tip of the microphone, causing hydrolysis that breaks the Fe-0-Fe bond in J-light. It is thought that this will cause a reaction and further develop the microphone.
そこで、発明昔らは、加工後の；ｊアスライグの表面に
微視的な範囲においても鏡面が保、１１Ｆさイ１ろ研磨
を行って表層のマイク〔ツクラックを除去した後、耐高
〃、高湿試験を行った結果、脱粒を抑えられることを突
き止めた。鏡面棚上はコアスライダの表面のうち大部分
について行うことが好ましい。Therefore, in the past, after processing, the surface of Aslig maintained a mirror surface even in a microscopic range, and after removing the microphone cracks on the surface layer by polishing the surface of Aslig, As a result of high-humidity tests, it was found that granulation can be suppressed. It is preferable to perform mirror polishing on most of the surface of the core slider.
つまり、通常、鏡面仕」二げを行うのは磁気ディスクに
対向する面の溝以外の部分のみであり、スライダの溝の
内側の面やスライダの側面、０字コアの外面はそのよう
な加工を行っていない。本発明はそのような箇所にも種
々の手段で鏡面仕上げ処理を行うようにしたものである
。その具体約手１段としては、例えば、スライダの底面
を平滑化４−ろには、砥石を用いて研削した後に、仕」
二げ砥石により研磨すればよく、同様に側面を鏡面を得
られる程の細粒度砥石で切断するか、あるいは細粒度の
砥石で切断した後に順次研磨する、あるいは、各加工面
毎に研磨剤を用いてラッピング加工をしてもよい。また
複雑な形状のコアスライダの全周面を少ない工程で平滑
化する方法として、サンドブラストや液体ポーニンク、
または、粘弾性を荷電る浦に砥粒を混ぜ、油圧をかけて
研磨を行う方法がある。さらには、ケミカルエヅヂング
のように化学的処理により平滑化する手段によれば、工
程がさらに単純化される。In other words, mirror polishing is usually applied only to the part other than the groove on the surface facing the magnetic disk, and such processing is applied to the inner surface of the slider groove, the side surface of the slider, and the outer surface of the 0-shaped core. has not been carried out. The present invention is designed to perform mirror finishing treatment on such locations using various means. One concrete way to do this is, for example, to smooth the bottom surface of the slider, grind it with a whetstone and then finish it.
All you have to do is polish it with a double grindstone, and similarly, you can cut the side surface with a fine-grained grindstone that gives you a mirror finish, or you can cut it with a fine-grained grindstone and then polish it sequentially, or you can apply an abrasive to each machined surface. It may be used for wrapping processing. In addition, sandblasting, liquid polishing,
Alternatively, there is a method of mixing abrasive grains in a viscoelastically charged ura and applying hydraulic pressure for polishing. Furthermore, the process can be further simplified by means of smoothing by chemical treatment such as chemical etching.
１作用］
このように構成された磁気ヘッド用コアスライダにおい
ては、切削等の機械加工により生じた表層の予測及びコ
ントロール困難なマイクロクラックか平滑化処理によっ
て除去されるので、このマイクロクラックを発生原因と
する静的疲労破壊の進展が阻止され、脱粒量が大幅に低
減される。1 Effect] In the core slider for a magnetic head configured in this way, microcracks in the surface layer that are difficult to predict and control caused by machining such as cutting are removed by smoothing treatment, so that the cause of the occurrence of these microcracks is eliminated. This prevents the development of static fatigue fracture and significantly reduces the amount of grain shed.
［実施例］ 以下、この発明の詳細な説明する。[Example] The present invention will be explained in detail below.
磁気ヘット用コアスライグの素材の製造方ｄ：を述へる
と、原料である金属の酸化物や炭酸塩など（例えば、ａ
Ｆｅ２Ｏ３，ＭｎＯ２，ＭｎＣＯ３，Ｚｎ０）をフ
ェライトの分子成分比に秤量し、これを機械的に混合し
、１０００〜１３００℃で加熱づ′ると、次に示すよう
な反応によりフェライトか生成さイする。Describing the manufacturing method d: of the material of core slig for magnetic heads, raw materials such as metal oxides and carbonates (for example, a
When Fe2O3, MnO2, MnCO3, Zn0) are weighed to the molecular component ratio of ferrite, mixed mechanically, and heated at 1000 to 1300°C, ferrite is produced by the following reaction. .
ＭｎＯ−１−ＦｅｔＯ３→ＭｎＦｃ、０４＋ Ｉ ／２
０゜ＺｎＯ＋ｌマｅ、ｏ３−〉ｚｎＦｅ２ｏ＋十＋ ／
２０２このようにして作った粉末を適当な可撓性容器に
入れ、静圧を与えて成形した後、焼結させると固相反応
により焼結フェライトか得られる。MnO-1-FetO3→MnFc, 04+ I/2
0゜ZnO+lmae, o3-〉znFe2o+ten+/
202 The powder thus produced is placed in a suitable flexible container, molded under static pressure, and then sintered to yield sintered ferrite through a solid phase reaction.
なお、粉末の製造方法としては、液相反応による方法を
用いてもよく、また、ポットプレス法により成形と焼結
を同時に行ってもよい。Note that as a method for producing the powder, a method using a liquid phase reaction may be used, or molding and sintering may be performed simultaneously using a pot press method.
このような焼結フェライトを、第１図に示すスライダ２
とほぼ回し大きさの長方形平板状とするように機械加工
を施して試験片を複数形成した。Such sintered ferrite is used in the slider 2 shown in FIG.
A plurality of test specimens were formed by machining them into rectangular flat plates approximately the size of a turn.
この試験片をラッピング加工して、表面粗度の５間なる
複数の試験片を作成し、耐高温高湿試験を行ったところ
、フェライトの脱粒確率（少しでも脱粒がおきた試験片
の割合）は第４図に示すようになった。すなわち、フェ
ライトの脱粒確率は表面粗度が低下するに従い減少し、
特にＲｍａｘ＝ ０．２７１ｍ以下とした場合には脱粒
がほとんど発生しないことが判った。This test piece was lapped to create multiple test pieces with five surface roughness levels, and a high temperature and high humidity resistance test was conducted. is now shown in Figure 4. In other words, the probability of ferrite shedding decreases as the surface roughness decreases,
In particular, it was found that when Rmax = 0.271 m or less, almost no grain shedding occurred.
なお、」１記実施例においては平滑化処理の方法として
ラッピング加工を採用したが、既述したように化学的、
物理的な種々の平滑化手段を適宜採用してもよい。In addition, in Example 1, lapping was used as the smoothing method, but as mentioned above, chemical,
Various physical smoothing means may be employed as appropriate.
［発明の効果］
以」二詳述したように、この発明は、フェライトを素材
とする磁気コア及びスライダを接合した後不要部を機械
加工して除去してなるコアスライダの表面を、Ｒｍａｘ
＝０．２μｍ以下となるように平滑化処理を施したこと
により、静的疲労破壊の原因となるマイクロクラックを
除去し、それにより、複雑な構造のモノリソツク磁気ヘ
ッド用コアスライダにおいても、比較的簡単な手段によ
りフエライトの脱粒を防ぎ、脱落粒子がヘッドと衝突し
て磁気媒体の磁性層を破壊することを防止するという優
れた効果を奏するものである。[Effects of the Invention] As described in detail below, the present invention provides a magnetic core made of ferrite and a slider that are joined together and then machined to remove unnecessary parts.
By smoothing the core slider so that it is less than 0.2 μm, microcracks that cause static fatigue failure are removed. This simple means has the excellent effect of preventing ferrite particles from falling off and preventing the falling particles from colliding with the head and destroying the magnetic layer of the magnetic medium.
第１図はこの発明の磁気ヘット用コアスライグの一例を
示す図、第２図及び第３図はその製造工程を示す図、第
４図は表面粗度と脱粒発生の確率の関係を示すグラフで
ある。Fig. 1 is a diagram showing an example of a core slig for a magnetic head of the present invention, Figs. 2 and 3 are diagrams showing its manufacturing process, and Fig. 4 is a graph showing the relationship between surface roughness and probability of grain shedding. be.
Claims (1)
た後、不要部を機械加工して除去してなるコアスライダ
の表面を、表面粗度０．２μｍ以下となるように平滑化
処理を施したことを特徴とする磁気ヘッド用コアスライ
ダ。After joining a magnetic core and slider made of ferrite, unnecessary parts are machined and removed, and the surface of the core slider is smoothed to a surface roughness of 0.2 μm or less. Features a core slider for magnetic heads.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63183279A JP2842873B2 (en) | 1988-07-22 | 1988-07-22 | Core slider for magnetic head |
| US07/355,217 US5037593A (en) | 1988-06-29 | 1989-05-22 | Method for fabricating core slider for a magnetic head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63183279A JP2842873B2 (en) | 1988-07-22 | 1988-07-22 | Core slider for magnetic head |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0233722A true JPH0233722A (en) | 1990-02-02 |
| JP2842873B2 JP2842873B2 (en) | 1999-01-06 |
Family
ID=16132876
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63183279A Expired - Fee Related JP2842873B2 (en) | 1988-06-29 | 1988-07-22 | Core slider for magnetic head |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2842873B2 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5296011A (en) * | 1976-02-06 | 1977-08-12 | Nippon Telegr & Teleph Corp <Ntt> | Production of magnetic head |
| JPS6161193A (en) * | 1984-09-01 | 1986-03-28 | 大阪シ−リング印刷株式会社 | Label paper |
| JPS6260117A (en) * | 1985-09-11 | 1987-03-16 | Toshiba Corp | Production of floating head slider |
| JPS63113818A (en) * | 1986-10-29 | 1988-05-18 | Tdk Corp | Manufacture of thin film magnetic head |
-
1988
- 1988-07-22 JP JP63183279A patent/JP2842873B2/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5296011A (en) * | 1976-02-06 | 1977-08-12 | Nippon Telegr & Teleph Corp <Ntt> | Production of magnetic head |
| JPS6161193A (en) * | 1984-09-01 | 1986-03-28 | 大阪シ−リング印刷株式会社 | Label paper |
| JPS6260117A (en) * | 1985-09-11 | 1987-03-16 | Toshiba Corp | Production of floating head slider |
| JPS63113818A (en) * | 1986-10-29 | 1988-05-18 | Tdk Corp | Manufacture of thin film magnetic head |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2842873B2 (en) | 1999-01-06 |
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| LAPS | Cancellation because of no payment of annual fees |