JPS6235506A - Magnetically soft amorphous material - Google Patents

Abstract

PURPOSE:To enable the manufacture of a magnetic head having high mechanical reliability without deterioration of magnetic properties even if a glass fusion- bonding process is employed by setting the number N of outer electrons of elements which form magnetically soft amorphous material and mean outer electrons obtained from atomic density (at.%) to N<=8.3. CONSTITUTION:A magnetically soft amorphous thin film formed by adding at least one type or more of metal elements of Zr, Hf, Nb, Ta, W, Mo, V, Ti, Re and Ru or metalloid element of B, C, Si and P to Co of main content of various composition is formed on a glass substrate by a high frequency magnetron sputtering method. The number N of mean outer electrons obtained from the outer electron number of the elements which form the magnetically soft amorphous material and an atomic density (at.%) is set to N<=8.3. If the number N is less than 8.3, crystallizing temperature T is 520 deg.C or higher, and even if the same heat treatment as glass fusion-bonding process is executed, the magnetic property of the magnetic material is not deteriorated at all but can sufficiently endure against the heat treatment at the glass fusion-bonding time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an amorphous soft magnetic material, and more particularly to a magnetic core material for a magnetic head.O (Prior Art) Amorphous soft magnetic material The material is attracting attention as a magnetic core material because it has superior soft magnetic properties, corrosion resistance, and wear resistance compared to crystalline soft magnetic materials, and has a large resistivity and can reduce eddy current loss. ] A known representative example of such amorphous soft magnetic material is CoayZr5Nbs (first
8th Tsuken Symposium Proceedings, page 111), co,!
Zr, (Journal of Applied Physics), 53,3
156.1982) is well known, in the manufacturing process of magnetic heads used in floppy disk drives, etc., in order to ensure mechanical reliability during sliding with the recording medium when forming the grab length, Q] in which glass welding is performed is usual.

(Problems to be Solved by the Invention) Since this glass welding process includes heat treatment at at least 450°C or higher, the properties of the amorphous soft magnetic material may deteriorate (for example, an increase in coercive force U and a decrease in magnetic permeability). happen. This is thought to be mainly caused by crystallization of the amorphous soft magnetic material. Therefore,
The amorphous soft magnetic material needs to have a crystallization temperature 'rx higher than the glass bath deposition temperature (450° C.) described in mJ.

According to the present invention Q), the above-mentioned amorphous soft magnetic material U)
Deterioration of magnetic properties is caused by amorphous soft magnetic material Q] Crystallization temperature I
Ill occurs at a temperature approximately 70'C lower than x, so the crystallization temperature Ill required for an amorphous soft magnetic material is
Specifically, it is necessary that 'rx≧520°C.

The above-mentioned known examples, namely Co67Zr5Nbl, C
oBZr501M crystallization Qi, degree T x are each 497°C,
This made it difficult to manufacture magnetic heads with high reliability, especially mechanical reliability. This has become a major industrial problem.

The purpose of the present invention is to achieve a crystallization temperature Tx of high<(Tx≧520
℃), and to provide an amorphous soft magnetic material that can withstand heat treatment during glass welding.

(Means for Solving the Problems) According to the present invention, in an amorphous soft magnetic material containing %co as a main component and adding at least one metal element or metalloid element, the amorphous An amorphous soft magnetic material characterized in that the average number of outer shell electrons N determined from the number of outer shell electrons and atomic concentration (at, %) of each element constituting the soft magnetic material is N≦8.3. is obtained.

(Example) The present invention will be explained below using Examples.

0 sputtering conditions in which amorphous soft magnetic thin films containing CO of various compositions as a main component and at least one metal element or metalloid element added were prepared on glass substrates using high-frequency magnetron sputtering. is input power 600
The W, Ar gas pressure is 5 x 10'' Torr, and the film thickness is about 1.0 μm.The target is a CO plate as a base target, and Zr is placed on top of this.

A nine-composite target was used in which chips of metal elements such as Ht or metalloid elements such as St and B were dispersed, and the composition was changed by changing the type, number, and arrangement of the chips. The sputtering method was used.

The sputtering method, which is commonly used as a method for manufacturing magnetic core materials for thin-film magnetic heads that have been put into practical use in recent years, is adopted, and the present invention is sufficiently effective even with other manufacturing methods. Of course. Note that the cobalt content in the prepared sample is 65 to 70 at% or more at the predetermined θ
] 0, which is desirable for obtaining magnetic properties.Twenty representative samples were selected from the manufactured amorphous soft magnetic materials, and their compositions, crystallization temperatures Tx, and average number of outer shell electrons N are shown in the table. Here, the average outer shell electron number N was determined from the outer shell electron number and atomic concentration of each element constituting each amorphous soft magnetic material. For example, sample l (7) CoBZr3
In Nbl, the number of outer shell electrons in Co is 9, in CdQ there are 7, and in S
Similarly, Zr and Nb each have 4
Since there are 5 pieces, multiplying each atomic concentration, the average number of outer shell electrons N is N=9 X O,92+4 X O,03
+5 X O, 0-5 = &65, and the composition is expressed in atomic concentration and determined by analysis with an X-ray microanalyzer.

In addition, the crystallization temperature Tx is determined by differential calorimetry method 7 (
Di f ferenlml Scanning C
alorimetry) f, and the temperature at which the measured exothermic peak rises was taken as the crystallization temperature Tx0. In addition, in cases where multiple exothermic peaks were observed, the temperature at which the exothermic peak at the lower temperature side rose was taken as the crystallization temperature. Tx
And so.

The measurement conditions were: sample Arashibon 20 mg + ascending rate 0°C/
The sample holder was made of gold.

In summary, the crystallization temperature Tx of the amorphous soft magnetic materials defined in the present invention, that is, the samples (numbers 9 to 20) with an average outer shell electron number N of 8.3 or less, is 520°C or higher. ,
Even when the same heat treatment as in the glass welding process was performed (temperature increase 20°C/min, holding time at 450°C 1 hour, cooling rate 5°C/min), no deterioration of magnetic properties was observed at all. It was confirmed that there was enough needle weight.

On the other hand, for amorphous soft magnetic materials other than those specified in the present invention, that is, samples (numbers 1 to 8) in which the average number of outer shell electrons N is more than 8.3, the crystallization temperature Tx is 520.
℃ temperature is also low, and as a result of the heat treatment mentioned above, the magnetic properties deteriorate significantly, and even the sample with the least deterioration,
The magnetic permeability decreased to about 1710, and the coercive force also increased significantly from 0.050e to 150e, making it clear that it could not be used as a magnetic core material.

Incidentally, the magnetic properties of the samples described in the examples are all coercive force He≦O, l Oe and saturation magnetic flux density Bs 8000.
(G) in a rotating magnetic field with magnetic permeability μ of 4800e.

10 by annealing at a temperature of 300°C for 3 hours.
μ at MHz was 2000 or more, and there were no problems at all.0 (Effects of the invention) As stated above, the amorphous soft magnetic material according to the present invention has a high crystallization temperature (Tx≧520°C). Therefore, even if a glass welding process is introduced, there is no deterioration of magnetic properties (therefore, it is possible to manufacture a magnetic head with high mechanical reliability, and the industrial value of the present invention is considered to be great.

Claims (4)

[Claims] (1) In an amorphous soft magnetic material comprising Co as a main component and at least one metal element or metalloid element added thereto, the outer shell electron number of each element constituting the amorphous soft magnetic material An amorphous soft magnetic material characterized in that the average number of outer shell electrons N, determined from the atomic concentration (at.%), is N≦8.3. (2) The metal element is Zr, Hf, Nb, Ta, W, Mo
, V, Ti, Re, Ru. (3) The amorphous soft magnetic material according to claim 1, wherein the semimetallic element is B, C, Si, or P. (4) The amorphous soft magnetic material according to claim 1, 2, or 3, wherein the amorphous soft magnetic material is a material used in a magnetic head manufactured by a glass welding process.