JPS6021217B2 - High magnetic permeability amorphous alloy with excellent heat resistance and corrosion resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high magnetic permeability amorphous alloy whose magnetic properties do not deteriorate even at high temperatures and which has excellent corrosion resistance and wear resistance.

So far, some amorphous alloys have been reported to have compositions that exhibit excellent magnetic sensitivity properties.

For example, Fe9.7Co70.3. Si15. B15 (atomic %), coercive force 0.00 but effective permeability (1 plate Hz)
10,500 (Arai, Tsuya, Yamada, Masumoto: Japan Institute of Metals, 7th Annual Conference Lecture Summary Elements, p. 86). However, the previously published amorphous alloy systems, including these, have the following two major drawbacks in terms of practical application. The first is the lack of heat resistance, and when the above alloy system is heated for a short time at a low temperature of 150 to 25 pi, the effective magnetic permeability decreases to less than half. Therefore, for example, even if an attempt is made to make a magnetic head core using such an amorphous alloy tape, the characteristics may deteriorate during the heating (usually 150 to 200°C for several hours) required for curing the resin during lamination, molding, etc. It deteriorates and cannot perform as a magnetic head.

Note that this deterioration in characteristics can be recovered by heating at a high temperature of around 420°C, and the degree of deterioration decreases with subsequent heating at temperatures below this level.Therefore, there have been attempts to use heads that have been previously subjected to high-temperature heat treatment, but this is due to the process This is not desirable because in addition to increasing the amount of water, another problem arises in that the material itself becomes brittle.

Generally, amorphous metals are in a thermodynamically unstable state, and it is inevitable that they will lose their excellent room temperature properties when heated. This is necessary, and the present invention makes this possible. In addition, high heat resistance means that it will not change over time during use, so from this point of view as well, the present invention can be said to have great practical value in terms of reliability of characteristics.

The second is that the hardness of the amorphous alloy is Hv=800-90.
Although the wear resistance is extremely high at 0, the wear resistance of the head is low.

This tendency is considered to be caused by corrosive wear since it is noticeable in environments with high temperatures and where corrosion is likely to occur.In this sense, it is necessary to improve corrosion resistance, and the present invention has made this possible.

That is, the present invention aims to overcome the drawbacks of these conventional amorphous alloys by changing the composition ratio of the metal elements Fe, Cr, and Co, and the ratio of these metal elements to the metalloid elements Si, B, C, P, and Ge. As a result of extensive and detailed examination of the characteristics of the composition ratio,
The present invention provides a high permeability amorphous alloy whose magnetic properties do not deteriorate even at high temperatures and which has excellent corrosion resistance and wear resistance.

The composition of the high magnetic permeability amorphous alloy with excellent heat resistance and corrosion resistance according to the present invention is summarized in the following '11, (2) based on the experimental results. '1' When the metal element is Fe, Co, Cr, and the metalloid element is Si, B, as is clear from Example 1, (FeaCrbCoc)×SiyBza+b+c=
When 1×10y+z=100 atomic%, 0.04Sa 0.06...(1) 0.01SbSO. 06...[21 0.88ScSO. 95...'3'70SxS80...'4' 8≦y≦22...■ 7mi zS20...(6} 20≦y+zS30...[7' A composition range that satisfies all formulas from [11 to [7'] above.

A more preferable composition range is 0 in place of the formula 01 to {7}.
．． 04Sa 0.06...(1') 0.03Sb 0.05...(2') 0.89Sc 0.93...(3') 71<x<75...(4) 15≦y ≦18...(5') 7SzSI4...(6') 25<y+Z<29...(7') A composition range that satisfies all formulas (1') to (7') above.

Among them, a particularly preferable composition is a=0.05 b=0
．． 04 c=0.91. ■ Examples when consisting of metal elements Fe, Co, Cr, metalloid elements Si, B, and one or more metalloid elements (M) selected from the element group of P, C, and Ge. As is clear from 2, when (FeaCrbCM) x SiyBzMw a + b + c = 1 x + y + z + w = 100 atomic %, 0.04 Sa mi 0.06... (1) 0.01 SDSO. 06...■ 0.88Sc mi 0.95...{3'70SxS85...{4'8≦y≦22...'51 7mi zS20...[61 wS2...'71 15≦y+zten wS30...{81 Above A composition range that satisfies all formulas '1-'8}.

The reason for limiting the composition range of the alloy of the present invention for each of the above '11 and (2) will be described below. In the above m, {2l,
Fe 0.04-0.06, Cr 0.01-0.06
, Co 0. The reason for setting it to ~0.95 is that outside this range, the coercive force increases and the effective magnetic permeability decreases, making it impossible to obtain magnetic properties suitable for practical use.

In particular, if Cr is less than 0.01, there is no effect of improving corrosion resistance, and if it exceeds 0.06, saturation magnetization is low and the Curie temperature is 100° C. or less, making it impossible to obtain sufficient magnetic properties. In addition, '1' is Fe, C
r, the total amount of Co is 70 to 80 at%, Si is 8 to 22 at%, B is 7 to 20 at%, and the total amount of Si and B is 20 to 20 at%.
The reason why it is set at 30 atomic % is that if it is outside this range, it will be difficult to make it amorphous, or even if it can be made amorphous, the effective magnetic permeability will be low.
Moreover, it has poor heat properties and cannot provide sufficient properties. Among them, the total amount of Fe, Cr, and Co is 71 to 75 atomic%.
, Si15-18 atomic%, B7-1 Hirofusako%, and Si
When the total amount of B and B is 25 to 29 atomic %, the effective magnetic permeability is particularly excellent, and the heat resistance and corrosion resistance are excellent.

In addition, in '2), the total amount of Fe, Cr, and Co was 70 to 8
The reason why the amount of metalloid elements (Si, B, P, C, Q) is set to 15 to 30 at % is that it is difficult to form an amorphous state outside this range.

Moreover, even if it can be made amorphous, sufficiently excellent magnetic properties cannot be obtained. An example of the method for manufacturing the alloy of the present invention is given in the examples, but it can also be easily manufactured by conventional methods such as the centrifugal stiffening method and the rolling quenching method (roll method). Some samples produced by the roll method are included in the examples of the present invention, but no differences were observed between them and those produced by the single roll method, so no particular distinction was made between them.

As described above, the high magnetic permeability amorphous alloy according to the present invention has excellent thermal magnetic properties, as well as excellent corrosion resistance and wear resistance. The material is ideal for use as core materials for magnetic heads, as well as for iron cores in devices, motors, etc. In particular, the core material of the magnetic head made of the alloy of the present invention does not deteriorate its magnetic properties even during the heating process during lamination and molding to form the core, and has stable performance even when used as a magnetic head for a long time. It has great industrial value.

EXAMPLES Below, the effects of the present invention will be explained based on examples in order to make them more concrete.

Example 1 The following composition (Fe
aCrbC skin) 74Si, 6B,.

The effective magnetic permeability and coercive force of the compositions 1 to 27 in Figure 1 were investigated for (a+b+Cd1) by changing a, b, and c.
Obtained the results in the table. The compositions 1 to 15 shown in the shaded area in FIG. 1 are better than the other compositions 16 to 27.
and 7, especially 7 showed extremely excellent magnetic properties. The numbers in the figure indicate composition numbers. The sample was operated as follows.

10 pieces of the alloy with the composition obtained by high-frequency melting were put into a quartz tube with a small hole of 0.8 ribs in diameter at the tip, and then placed in a high-frequency heating furnace without flowing argon gas through the tube. Dissolved. When the temperature of the molten metal reached 110 pm, it was pressurized to 0.2 k9/mm using argon gas, and the molten metal was moved up and down at the tip of a quartz tube onto the surface of a roll with a diameter of 200 mm and rotating at high speed at a rotation speed of 400 pm. Spray out and cool down quickly, about 1
．． An amorphous metal tape with a thickness of about 28 mm and a thickness of about 2 mm was obtained. When this was examined by X-ray diffraction, a halo pattern characteristic of amorphous metals was obtained, confirming that it was amorphous. Next, magnetic measurements were performed as follows.

The obtained amorphous tape was wound in 20 layers around porcelain with a diameter of 25 mm while applying magnesia between the layers, and a primary coil and a secondary coil were respectively wound thereon to form a measurement sample. Static magnetization characteristics were measured using a BH characteristic recording device made by Riken Denshi and an impedance measuring device made by Yokogawa for high frequency characteristics (Oroyama constant magnetic field 0.3hoe).
). Table 1 Next, the experimental results in FIG. 2 show that the alloy of the present invention has excellent heat resistance.

The samples were Invention Alloys 14, 11, 10, 7, and 14, 11, 10, and 7 of Table 1, in which the Fe composition ratio was kept constant at 0.05 and the Cr composition ratio was varied.
5,2 and a comparative alloy not containing Cr.

As is clear from Fig. 2, the crystallization temperature Tx increases and the Curie temperature Tc decreases due to the addition of Cr;
An increase in the crystallization temperature means that the region in which the alloy of the present invention stably exists as an amorphous state expands.

Moreover, if Cr exceeds 0.06, the Curie temperature becomes lower than 150 pm, making it unsuitable for practical use. Figure 3 shows the same sample as in Figure 2 in the rapidly cooled state, and the sample at 250°C.
The effective magnetic permeability is shown using an IS holding machine and air-cooled conditions.
This figure also shows that the effective magnetic permeability of the alloy of the present invention does not deteriorate due to heat treatment. Example 2 Table 2 shows the composition ratio of the metal elements as Fe:Cr:Co=0.05:0.04:0.91, which is the same as the invention alloy 7 in Table 1.
The results are for compositions in which the metalloid elements were changed to Si + BZ26, and small amounts of P, C, and Q were added.

It can be seen that when Cr is added, as long as the composition ratio of the metal elements is constant, the excellent properties are not lost even if the amount and type of the metalloid elements are slightly changed. Table 2 Example 3 Invention alloy 7 of Table 1 Fe3.7Cr2.9 o67.3 cord 10 (Tc
=20000), conventional alloy Fe4.7Co70. $il
FIGS. 4 and 5 show the results of examining the heat resistance of the magnetic properties of Tc 10 (Tc=3670).

Figure 4 shows the results of measuring the effective magnetic permeability (Hz, measured magnetic field: 0.3 hoe) after holding each heat treatment temperature for 18 minutes, cooling in air, and Figure 5 shows the results of heating at ~3°C/min from room temperature. These are the results of measuring the effective magnetic permeability (Tsumugi Hz, measurement magnetic field 0.3 hoe) at each temperature.

In all cases, the vertical axis indicates the effective magnetic permeability in the rapidly cooled state (the state of the amorphous alloy) as 1, and the ratio thereof is shown as 1. As is clear from these figures, the magnetic properties of the alloy of the present invention not only do not deteriorate even when the temperature increases, but they actually improve when heated up to 250°C.

Example 4 To examine the corrosion resistance of magnetic tape,
Invention alloy 2, shown in Table 1, was added to 50 cc of a corrosive liquid (pH 5.1) obtained by soaking one magnetic tape (chromium oxide tape) for one magnetic recording cassette in distilled water at 250°C for one week. 7, 11, 15 amorphous metal tape and conventional alloy F
e4.7Co70. $ilyu10 amorphous metal tape (
Table 3 shows the results of observing the state of corrosion after allowing the specimens (middle 5 skin, thickness 35 r, length 100 side) to soak in water and leave to cool in the air.

3 tables Note) A: No corrosion observed.

B: Slight discoloration of the surface was observed. C
: Corrosion is clearly recognized. D: Corrosion has progressed further. This shows that the alloy of the present invention does not discolor for a long time and has excellent corrosion resistance.

[Brief explanation of the drawing]

Figure 1 shows the F of the invention alloy and comparative alloy in Example 1.
A chart showing the ternary composition ratio (atomic ratio) of e, Cr, Co,
Fig. 2 is a chart showing changes in crystallization temperature Tx and Curie temperature Tc depending on the composition ratio of Cr of the alloy of the present invention in Example 1, and Fig. 3 shows the rapid cooling state according to the composition ratio of Cr of the alloy of the present invention in Example 1. and a chart showing changes in effective magnetic permeability after heat treatment; FIG. 4 is a chart showing changes in effective permeability ratio depending on heat treatment temperature; FIG. It is a chart showing changes in the ratio of magnetic susceptibility. Figure 1, Figure 2, Figure 3, Figure 4, Figure 5

Claims (1)

[Claims] Consisting of metallic elements Fe, Co, and Cr and metalloid elements Si and B, having a composition expressed by the linear formula (FeaCrbCoc)×SiyBz (where a+b+c=1, x+y+z=100 atomic %) In the amorphous alloy, the following formulas (1) to (7) 0.04≦a≦0.06...(1) 0.01≦b≦0.06...(2) 0.88≦c≦0. 95...(3) 70≦x≦80...(4) 8≦y≦22...(5) 7≦z≦20...(6) 20≦y+z≦30...(7) It is characterized by simultaneously satisfying the following. High magnetic permeability amorphous alloy with excellent heat resistance and corrosion resistance. 2 Conditions (1) to (7) in Claim 1
Heat resistance by narrowing the formula using the following conditions (1') to (7'),
High magnetic permeability amorphous alloy with excellent corrosion resistance. 0.04≦a≦0.06...(1') 0.03≦b≦0.05...(2') 0.89≦c≦0.93...(3') 71<x<75...(4 ') 15≦y≦18...(5') 7≦z≦14...(6') 25<y+z<29...(7') Cubic formula (FeaCrbCoc)×SiyBzMw (however, a+b+c=1, x+y+z+w=100 atoms %) and metallic elements of Fe, Co, and Cr and S
i, B metalloid element and any one of P, C, Ge
In an amorphous alloy consisting of a species or two or more metalloid elements (M), the following formulas (1) to (8) 0.04≦a≦
0.06...(1) 0.01≦b≦0.06...(2) 0.88≦c≦0.95...(3) 70≦x≦85...(4) 8≦y≦22...(5 ) 7≦z≦20...(6) W≦2...(7) 15≦y+z+w≦30...(8) A high magnetic permeability amorphous alloy having excellent heat resistance and corrosion resistance.