JPS61215252A - Material for magnetic head slider - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application This invention relates to a slider material for magnetic disks and a wear-resistant functional material for magnetic tapes, and more particularly to a material for magnetic heads and sliders that has excellent compatibility with recording media and lubricity. .

Background technology Until now, it has been used for computers, audio, and VTR.
Polycrystalline NL'In ferrite, lln-Zn ferrite, single-crystal 11n-Zn ferrite, or high-hardness permalloy has been used for magnetic heads and sliders for recording and reproducing purposes.

Nowadays, there is a strong desire for higher recording densities and improved wear resistance, and the use of thin film magnetic heads is progressing even further. With the trend toward thin-film magnetic heads, optimal materials that satisfy the required characteristics are being selected for each of the magnetic circuit member material for recording and reproduction and the wear-resistant slider material.

That is, for magnetic circuits, it is considered desirable to use permalloy, sendust, or amorphous thin films that have excellent magnetic properties in the high frequency range, while for functional parts that require wear resistance, it is considered desirable to use alumina-based materials. ing.

Such materials for wear-resistant sliding members are non-magnetic materials, but have excellent wear resistance, precision machinability, machining efficiency, high strength, dense structure, rough compatibility with recording media, and smoothness. , various properties such as thermal compatibility with metal thin films and adhesion strength are required.

Conventionally, A12o was used as a material for magnetic heads and sliders.
3Tic material (Japanese Unexamined Patent Publication No. 163665/1983) is
It has excellent properties and is one of the most suitable materials for such wear-resistant functional members, but it is also compatible with recording media.

It is not necessarily a stable material in terms of lubricity, and in particular, in the case of thin film recording media that are expected to be put into practical use in the future, i.e., plating media or sputtering media, the thickness of the media will become thinner and the lubrication of the media will increase. Problems arise in terms of providing a transparent thin film, etc.

In other words, the hardness of soft ferrite, which has been stably used for a long period of time, is ()iv) -
600-800, while the above M, 03-T
Since the hardness of the IC material is (lv)=1900 to 2100, it may be difficult to apply the above material depending on the target medium.

Tide is a material for magnetic heads and sliders that improves the compatibility and lubricity of HzO3Tic materials with recording media.
M20z material (Japanese Patent Application Laid-Open No. 198578/1983) was proposed and has extremely excellent properties in many aspects.
It is one of the most suitable materials for the wear-resistant functional component material,
There is a problem that the material has poor machinability, and there is a strong demand for improved machinability as a material for magnetic heads and sliders.

Purpose of the Invention This invention addresses the requirements for wear-resistant functional members of magnetic heads and sliders, including wear resistance, precision machinability, machining efficiency, high strength, dense structure, compatibility with recording media, i1
The object of the present invention is to provide a material for magnetic head sliders that satisfies various properties such as 1. lubricity and has particularly excellent machinability.

Structure and Effects of the Invention In view of the above-mentioned problems, the present invention has been made as a result of various studies on materials for magnetic head sliders with particularly excellent machinability. It has been discovered that by containing a specific amount of ZrO2, a material that satisfies various properties required for a wear-resistant functional member of a magnetic head slider and has excellent machinability can be obtained.

That is, this invention includes Tie, 20wt% to 60wt%, AI, 0380
For 100 parts by weight of a composition consisting of wt% to 40 wt%, 5.5 to 15 parts by weight of at least one of Mc+O and Y2O3, or roughly 0.2 to 3.5 parts by weight of ZrO2. A magnetic head/slider material characterized by containing:

In more detail, for example, the material according to the invention has T
iO220wt%~60wt%, Al2o3 aowt
% to 40 wt% of high purity oxide raw material, 5.5 parts by weight to 15 parts by weight of high purity MgO and/or Y2O3, or roughly 0.2 parts by weight to
After adding 3.5 parts by weight of ZrO2 raw material, pulverizing and mixing, roasting at 100°C to 1300°C, re-pulverizing,
Shaped by dry press, wet isostatic press, doctor blade method and other various forming methods, and the molded body is sintered at 1300°C to 1600°C in an atmospheric atmosphere, or by hot press method or hot isostatic press method. Obtained by sintering.

The M2O3-7iQ2-based magnetic head/slider material according to the present invention is different from conventional ferrite-based materials in terms of Mth
As an intermediate material with Tic-based materials, it satisfies various properties such as wear resistance, precision workability, processing efficiency, high strength, and dense structure required for such materials, and is compatible with recording media. Not only does it have excellent conformability and lubricity, but it also has excellent precision machinability and machining efficiency that conventional materials do not have.

Reason for component limitation In this invention, Tide is the main component of the aqueous material together with M2O3, and if it is less than 20 wt%, Tide is the main component of the water-based material.
As the hardness of LOe-based sintered bodies increases, the difference in hardness from soft ferrite, which has been widely used as a material for magnetic circuits in magnetic heads, becomes large, and depending on the recording medium, it may be difficult to apply soft ferrite. , also 60
If it exceeds wt%, vacancies are generated and it is not suitable as a material for a magnetic head, so it is set at 20 wt% to 60 wt%.

M2O3 is a main component of the aqueous material along with lower Lo2, and by limiting the content range of <TL 02 as described above, it becomes a range of aowt% to 40wt%.

At least one of Mgo and Y2O3 is added in order to improve the machining efficiency of ceramic materials and the sinterability of Al2O3 TLO2-based materials. If less than 5 parts by weight is added, the effect of improving the free machinability of the material is small, and if it exceeds 15 parts by weight, fine cracks will occur during sintering, making the material unsuitable for magnetic heads and sliders. , TLOes For a total of 100 parts by weight of Al2O3, 5
゜5 to 15 parts by weight should be added. Further, the preferable addition range is Mc+0 5.5 parts by weight to 8 parts by weight, Y2
The amount is 38 parts by weight to 12 parts by weight.

ZrO2 is added to improve the lubricity of the material with the recording medium and the strength of the compact.
In a composition containing 5.5 to 15 parts by weight of 3 and Zr02, if the amount is less than 0.2 parts by weight, the above effects will be small, and no improvement in water-based structure or strength will be obtained;
．． If more than 5 parts by weight is added, the hardness will be significantly lowered and precision processing will become difficult during processing of the molded product, making it unsuitable as a thin film magnetic head material.
Addition is 5 parts by weight.

In addition, in this invention, the initial purpose can be achieved even if ZrO2 is used as a raw material having the following characteristics.

ZrO2 powder raw materials include unstabilized powder containing no stabilizer, Y2O3, Mgo, Q1203, and CaO.
There are powders that have been partially stabilized or stabilized with, etc., and any of these powders can be used.

However, in order to obtain better materials, unstabilized ZrO
When using 2 powder, the purity should be 99.9% or more and the average particle size should be 0.11s or less, and by finally making it exist in the state of tetragonal and cubic crystals, the effect of improving the structure and improving the strength can be obtained. It will be done.

When partially stabilized or stabilized ZrO2 powder is used, 1.5 to 7 mo1% Y2O3ZrO2 system is used.
The use of powder with an impurity content of 0.1% or less and an average particle size of 013 m1 or less provides the best results in terms of structure improvement effect and strength improvement effect.

Example: N2O3 with purity 99.9%, average particle size 0.6IEn, TiO2 with purity 99.9%, average particle size 0.3JXn, Y2O3 with purity 99%, average particle size 1, purity 99%, average MgO1 with particle size 0.5Is average particle size 0.2. can's Zr
Using each powder of 02 (Zr02-2.5 mo1% Y2O3), 5.5 parts by weight of Mc+0 was added alone to 10 parts by weight of a mixed powder consisting of 60 wt% Al2O3-10240 wt% (Invention A
) Combined addition of 7 parts by weight of Mg0 and 23 parts by weight of ZrO (invention B) Single addition of 10 parts by weight of M2O3 (invention C) M
A composite mixture of 10 parts by weight of 2O3 and 3 parts by weight of ZrO2 (invention D) was blended, and wet mixing and pulverization was performed in a ball mill for 20 hours.

Next, this mixed powder was roasted at 1300° C., and then subjected to wet mixing and pulverization in a ball mill for 20 hours to obtain a sintering powder.

Next, fill the mold with the above sintering powder and heat it to 1300℃~
At 1600℃, apply a pressure of 200 kq, J and hold for 1 hour, then reduce the pressure and let it cool. Dimensions: 50 mm x 50 m.
A sintered body of m×5.5 mm was obtained.

- The physical properties of the sintered body according to the present invention are as follows.

Invention A (Al2O360wt%-Tio240wt%)
100: MgO5,5a specific gravity; 3.95 b hardness: HRA 90.0-90.6C folded crab 35
- Hashi d thermal conductivity; 0.027 Cal/Cm5eC''C Invention B (Alz(h6wt%-TLO240wt%)
100: MCl0 7.5; rO23 a specific gravity: 4.02 bf! ! Degree: HRA 90.3-90.8C transverse rupture strength;
42 Unicentric thermal conductivity; 0.027 Cat/Cm5eC'C Invention C (Al2O3aowt%-TiO240wt%) 1
00: Y2O310a specific gravity: 4.20 b hardness; HRA 91.0-91.8C bending crab
40kqJ dThermal conductivity: 0.030 cat/cmsec ”c
Present invention D (AlhO360wt%-TiO,4Qwt%) 1
00: Y2O310:ZrO23 a specific gravity: 4.21 b hardness; HRA 91.4-92.0C transverse rupture strength; 4
0-D thermal conductivity; 0.028 cal/cmsec ℃ prong ■2 The test pieces of various materials of Example 1 and the conventional composition test pieces shown in Table 1 were fixed with a jig, and a pulley was attached to this. 10k through
A test was carried out in which a test piece was cut into a length of 50 mm by the weight of the weight using a resin diamond cutting wheel with a weight of
203 ・40Ti02 ・3 When evaluating the machining efficiency based on the cutting time of ZrO2, this invention test piece was 1
It showed a processing efficiency of 10% to 200%. That is, it can be seen that the material of the present invention has excellent machinability even though it has higher hardness than conventional materials.

Table 1: The test piece of Example 1 was polished to 2 mm by using a diamond grindstone.
A rectangular parallelepiped with a cross section of X 4 mm and a length of 20 mm, its -
The end is shaped into a sharp blade shape. Rough, outer diameter 45mm
Using a donut-shaped disk of ferrite with an inner diameter of 10 mm and a thickness of 10 mm, combining it with the sintered body of the present invention, and bringing the sharp cutting edge of the sintered body into contact with the rotating ferrite,
A so-called pin-disc type wear test was conducted.

In addition, during the above test, conventional ferrite materials (Mn-Zn polycrystalline ferrite, tlno 32Wj%, Zt+0215Wj%, F
e2O253Wj%), Al2O3Tic sintered body (A
bO370wt%, Tic 30wt%) Ding Lot Ah03-based sintered body (TiO230wt%,
A similar wear test was conducted using Al2O3yowt%).

The test results are shown in Tables 2 and 3. Table 2 shows the hardness and wear of the sintered body, and Table 3 shows the wear amount of the mating material.

As is clear from the results in Table 2 and Tables 1 to 3, the magnetic head/slider material according to the present invention has hardness that is intermediate between conventional ferrite-based materials and N2O3TLC-based materials. It not only satisfies various properties such as abrasion resistance required for application materials, and has excellent compatibility with recording media and lubricity, but also has superior performance, particularly in R concave machinability, which is not found in conventional materials.

Claims (1)

[Claims] 1 TiO_2 20wt% to 60wt%, Al_2O_3
5 parts by weight of at least one of MgO and Y_2O_3 to 100 parts by weight of the composition consisting of 80 wt% to 40 wt%.
．． A material for a magnetic head/slider, characterized in that the material contains 5 to 15 parts by weight. 2 TiO_2 20wt%~60wt%, Al_2O_3
5 parts by weight of at least one of MgO and Y_2O_3 to 100 parts by weight of the composition consisting of 80 wt% to 40 wt%.
．． 5 parts by weight to 15 parts by weight, and further 0.2 parts by weight of ZrO_2
A material for a magnetic head/slider, characterized in that it contains from 3.5 parts by weight to 3.5 parts by weight.