JPS6018739B2 - Amorphous magnetic alloy - Google Patents

Description

[Detailed description of the invention] The present invention relates to ultra-quenched amorphous magnetic alloys.

Since ultra-quenched amorphous alloys have many characteristics, various applications are being investigated. For example, high-density magnetic recording has become a trend of the times, and recording media with high coercive force are being manufactured, so that the magnetic core material of the recording head is required to have a high saturation magnetic flux density. In general, magnetic core materials for recording and reproducing heads are required to have many more properties in addition to having a high Bs. In other words, the magnetic properties are stable against external stress, the wear resistance is high,
It has high resistance to insects, high thermal stability, etc.
According to conventional research, since amorphous alloys have high mechanical hardness (for example, Vickers hardness is 900), it is easily assumed that they have high wear resistance, and it has also been reported that they have high corrosion resistance. Furthermore, since amorphous magnetic alloys in a rapidly cooled state have inherent strain, attempts have been made to improve their properties by heat treatment. That is, for an amorphous magnetic alloy that can be easily heat-treated, it is necessary that its crystallization temperature Tx is higher than the magnetic Curie temperature Tc.
When carried out within the range of force c<T<Tx, the permeability peak e is increased and at the same time the thermal stability is also increased. Therefore, Tx>Tc can also be seen as one of the required conditions. Looking at the ultra-quenched amorphous magnetic alloys that have been studied to date from this perspective, although they satisfy requirements 1 and 2, it is difficult to find one that satisfies all requirements at the same time. A particular object of the present invention is to provide an amorphous magnetic alloy that is excellent as a magnetic core material for a magnetic head. The present invention will be explained in detail below.

As is well known, the ultra-quenched amorphous magnetic alloy contains a combination of one or more of Fe, Co, and Ni, which are ferrous transition metal elements, in an atomic ratio of 70 to 80 qo, and B, which is a semimetal element.
, C, Si, etc. in an atomic ratio of 30 to 20% are famous. Among them, those based on Co have a low Bs, but there are compositions close to 0 in S (saturation magnetostriction). On the other hand, those based on Fe have a high value, but the input s is also positive and large. Figure 1 shows the -2 clear ix of Col based on Co.
This is a summary of conventional research results regarding the alloy Bx,^s30. As you can see from this, increasing the ratio of ferrous transition element/metalloid results in magnetization. In other words, Satoshi will become taller, but
Tc has also become high and Tx has become low. This is generally true. This Co-based amorphous magnetic alloy shows a relatively high matrix region, so T
x Tc, and even if heat treatment is performed, the above-mentioned effect cannot be achieved. The present inventors first studied a Co-based amorphous magnetic alloy from the viewpoint that it must be an amorphous magnetic alloy that is stable against external stress.

In other words, when a ternary amorphous magnetic alloy of CoSiB is based and various fourth elements are added singly or in combination, what kind of fluctuations do the 0, Tc, and Tx of these alloys exhibit? As a result of detailed research, it was discovered that by substituting a part of Co with manganese and Mn, a previously unknown significant effect was exhibited between 〇, Tc, and Tx. Based on this. That is, the inventors have discovered that there may exist a composition where Bs is high, Tx>Tc, and input s is 0. The most remarkable effect of the present invention is that a significant increase in Tx was observed due to Mn substitution. Conventionally, it is well known that in this type of alloy, Tx can be increased by increasing the amount of metalloid elements, but increasing Tx in this way leads to a significant decrease in Bs, and the original value as a magnetic alloy is lost. This reduces the However, the present invention has the effect of increasing Tx without degrading Bs. 4 Figure 2 shows Co78
Si,. We have summarized the changes in 〇, Tc, and Tx when a part of Co in the amorphous magnetic alloy B is replaced with Mn. If we increase x of B.
(room temperature) increases slightly, a small maximum is observed near x=2, remains almost constant near x=3 to 4, and decreases monotonically and gently as x is further increased. Furthermore, Tc decreases significantly as x increases, while Tx increases with x, becoming significantly higher when x>4. This effect is very important and beneficial. This is because Co78Si,. B,
The amorphous magnetic alloy has a high H of approximately 9 μ/μ, but Tc is 515°C or higher (an unlikely value) and Tx is 4.
Since it is 23:00, no heat treatment effect can be expected since Tx<Tc.

However, for example, if x=5, Co73M is Si, . B.
．． A new amorphous alloy. is 9 $mu/night, Tc is 420oo, Tx is 520, and Tx>Tc. Therefore, by setting the heat treatment temperature to 435q0, the above-mentioned effects can be obtained. In this way, CoSiB
By introducing Mn into the amorphous magnetic alloy, it is possible to realize Tx>Tc without reducing 〇.
The effect of increasing Tx in this way can also be seen by introducing Mn into the CoB C-based amorphous magnetic alloy, but it is somewhat small. Next, CO flowers-xMnxSi, . B.. Figure 3 shows the results of an investigation on the saturation magnetostriction s in the amorphous magnetic alloy.

It has also become clear that although Mn substitution tends to make ^s slightly positive, it does not significantly increase it. Originally, Co78S
i,. Alloy B has a small negative value of -5x10-6. When Co in this alloy is replaced with Mn, the input s becomes smaller as x increases, and the input s becomes 0 when x is around 7. The effect of substituting Mh at 0 in this way increases Tx without deteriorating the magnetism, making it possible to create an alloy with ^s near 0. Co/Si in COSiB alloy
As a result of research on Mn substitution based on materials with different +B ratios, the most effective composition range was clarified, and the reason for this limitation will be described below. Generally Co. oo-x-(v+w)
When expressed by the composition formula MnxSivBw, 10Sv
An amorphous alloy phase exists in the region +wS30, and C
When replacing part of o with Mn, OSv≦15,10S
It is effective when 0.5SxSI0 under w≦25.

In other words, the effect of substitution is not significant when x<0.5, and x>
10 is very preferable because it increases Tx, but it does not meet the requirements of an amorphous magnetic alloy with high saturation, which is the original gist of the present invention, and Bs decreases. Therefore, from the viewpoint of industrial value of applying the alloy of the present invention to various electronic parts, it is designated as xSI0. However, since the effect of increasing Tx can be obtained even outside this range, it would be beneficial from the standpoint of utilizing a thermally stable amorphous alloy. Figures 5, 6, and 7 summarize the behavior of 〇, Tc, and Tx when part of Co is replaced with Mn in CoFeSiB alloys with different composition ratios of ferrous transition metals and semimetals. be.

That is, Fig. 5 shows (Fe4.6/7 and o70.4/75)
77-xMnxSi, Shi5 & Shi5 amorphous alloy, Figure 6 shows (Fe4.6/75Co70.4/75)78~
MnxSi,. B, amorphous alloy, Figure 7 is (Fe
4.6/7 o70.4/75) MnxSi...5B
, o. This study investigated the changes in 0, Tc, and Tx of 5 amorphous alloys. In all alloy systems, there is a maximum of 0 near x = 2, and Tc decreases significantly as x increases, but Tx It becomes significantly higher as x increases.
Therefore, the present invention provides an amorphous magnetic alloy that is particularly excellent as a magnetic core for a magnetic head, which has a high magnetic flux density due to Mn substitution, has a high Tx, and satisfies both the requirements of Tx-Tc>0 and input s of 0. This solves at once the drawbacks of conventional Co-based amorphous alloys in that increasing the base height increases rc and lowers Tx. Examples of the present invention will be described below. Note that the experimental methods carried out for the purpose of the present invention will also be mentioned. To create an amorphous alloy, raw materials were mixed, placed in an alumina crucible, and melted by high-frequency heating in an argon atmosphere to obtain a master alloy. Put this into a quartz nozzle and remelt it.
The molten material was jetted onto the outer circumferential surface of a steel roll rotating at a speed of 120 pm to ultra-quench the melt to obtain an amorphous alloy ribbon. Further, the amorphous alloy phase was easily determined by X-ray diffraction method. ○ was determined using a vibrating sample magnetometer, Tc was determined using a magnetic balance, and Tx was determined using DTA. The coercive force Hc is determined by obtaining the static magnetization curve using an automatic magnetometer, and the magnetic permeability peak e is determined by punching out 8 skin outer diameter x 4 leg inner diameter rings from the above two skin samples, laminating lq women and making 15 turns. Winding of
Maxwell bridge: Measured under a low ratio magnetic field at IKHZ. Also, ^s is measured by punching out five disks with an outer diameter of 8 ribs from an amorphous alloy ribbon, stacking them, and using the strain gauge method. Example 1 Fe2. ECo7,. 5M~. oSi,. The composition of B2 was made into an amorphous alloy by the single roll method.

Its properties are shown in the rapidly cooled state. is 9th mu nota, Hc is 20
Yanagi○e, Yamae is 10,000, Tc is 428q○, Tx
was 495o○. The magnetic properties after 20 minutes of heat treatment with 4560 are as follows: Hc is 10 skin○e, Buddha e is 40,
It was 000. The input s was almost zero. Example 2 Fe2.5Co7,. 5Mn8. .

The composition of Si8B,5 was made into an amorphous alloy by a single roll method. Its characteristics are in the rapidly cooled state. 9&mu/evening, H
c is 20 k, mountain e is 10,000, Tc is 456 q○
, Tx was 48,800. This is 10 at 465 o'clock
When heat treated for minutes, its magnetic properties are as follows: Hc is 15 degrees.
e,mu e became 30,000. The input s was almost zero.

[Brief explanation of drawings]

Fig. 1 shows the relationship between magnetization, Curie temperature, and crystallization temperature with respect to the composition of a conventional COSiB-based amorphous alloy, and Fig. 2 shows the relationship between magnetization, Curie temperature, and crystallization temperature with respect to the Mn content of the CoMnSiB-based amorphous alloy obtained by Mn substitution according to the present invention. A diagram showing the relationship between crystallization temperature, Figure 3 is CoMnSi
FIG. 4 is a diagram showing the relationship between saturation magnetostriction and Mn content in a B-based amorphous alloy. FIG. is FeCoMnS
Figure 6 shows the relationship between magnetization, Curie temperature, and crystallization temperature with respect to the Mn content of i B-based amorphous alloys.
A diagram showing the relationship between magnetization, Curie temperature, and crystallization temperature with respect to the Mh content when the amount of iron-metal transition metal elements is changed in a CoMnSiB-based amorphous alloy. Magnetization with respect to the amount of Mn when changing the amount of metal elements,
It is a figure showing the relationship between Curie temperature and crystallization temperature. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1 Consisting of cobalt (Co), manganese (Mn), and boron (B), Co_1_0_0-x-(v+w)
In the composition formula represented by MnxBw, 0.5≦x≦
10 10≦w≦25 15≦v+w≦30 An amorphous magnetic alloy having a crystallization temperature higher than the Curie temperature. 2 Cobalt (Co), manganese (Mn), silicon (S
i) and boron (B), Co_1_0_0-x
In the composition formula represented by -(v+w)MnxSivBw, 0.5≦x≦100 0<v≦15 10≦w≦25 15≦v+w≦30, and the crystallization temperature is higher than the Curie temperature. Amorphous magnetic alloy.