JPS5811503B2 - Wear resistant high permeability alloy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in Fe-Al-8i high magnetic permeability alloys.

Fe-Al-8i based high magnetic permeability alloy is usually called sendust, and the one with the best properties is Si9.6%, A
It is an alloy consisting of 15.4% Fe and the balance Fe.

This alloy has an initial permeability of 35100 and a maximum permeability of 11750.
0, coercive force 0.0220e, saturation magnetic flux density approximately 11000G
It has excellent soft magnetic properties with a specific electrical resistance of 80 μΩ/1 m, high magnetic flux density, and relatively high electrical resistance. Combined with its high hardness, it has ideal properties as a core material for magnetic heads. It is something that

That is, permalloy, soft ferrite, etc. are currently mainly used as magnetic heads for analog and digital magnetic recording and reproduction, but the former has problems with wear resistance, and is only partially put into practical use. A problem with wear-resistant permalloy is magnetic flux density.

On the other hand, soft ferrite has a definite limit in magnetic flux density and also has the problem of noise generation peculiar to ferrite.

In contrast, Fe-Al-8i high magnetic permeability alloys, so-called sendust alloys, have no problem with magnetism as described above.

Furthermore, although it is somewhat inferior to ferrite in terms of wear resistance, it is significantly superior to Vermaro C type m materials, and has recently come to be used as a head material for magnetic recording and reproducing devices. .

However, although the wear resistance of sendust is significantly superior to that of permalloy-based materials, it is inferior to ferrite, and its wear resistance may not be sufficient depending on the application.

That is, when Sendust is used as a magnetic head core for a VTR, card league, etc., the relative speed or contact pressure with the recording medium is low, resulting in severe wear of the core and a short lifespan of the magnetic head.

The present inventors proposed an Fe-8i-AI-Cr-Ni alloy having excellent corrosion resistance and wear resistance as a solution to the above-mentioned drawbacks (Japanese Patent Application Laid-Open No. 5O-119298).

However, since this alloy system contains Ni,
In order to provide excellent wear resistance and good magnetic properties at the same time, it is necessary to control the manufacturing conditions quite strictly.
It is not always completely satisfactory.

The object of the present invention is to improve the drawbacks of the above-mentioned alloys and to provide an alloy that has high magnetic permeability and excellent wear resistance.

In order to achieve the above object, the present invention has an AI of 2.5 to 8%.
4.0-16% Si, 0.2-15% Cr.

It is characterized in that the remainder is mainly composed of Fe.

Furthermore, in the above alloy, as a subcomponent, in weight ratio, 0.1 or more 5% or less Ti O,1〃5〃C.

O, 2〃2〃W Q, Ql 〃1〃Rare earth 0.1 〃Less than 0.5% Cu O,1〃0.2〃Nb O,1〃O,2〃Ta O, 2〃0.5〃M.

The total amount of one or more elements selected from the following is 0.
．． By containing 01 to 6%, wear resistance can be further improved.

In the present invention, the optimal amount of AI is 5 to 6%, but due to the relationship with Si and other alloying elements, a sufficiently good magnetic permeability can be obtained even in the range of 2.5 to 8%. , the lower limit is 2.5% and the upper limit is 8%.

The optimum amount of Si is 8 to 11%, but the lower limit is set to 4 because it has a sufficiently good magnetic permeability even in the range of 4 to 16%.
%, with an upper limit of 16%.

Cr has a great effect in significantly improving the wear resistance of the alloy of the present invention, but if the amount is less than 0.2%, the effect is not obvious, and if the amount exceeds 15%, the magnetic permeability decreases. In either case, the magnetic flux density decreases significantly, making it impractical.

The Fe-Al-8i-Cr alloy with such a composition has high magnetic permeability and excellent wear resistance.

Furthermore, if the content exceeds 5% of Ti, 1% of rare earth elements, and 2% of Nb and Na, it becomes mechanically brittle and becomes extremely difficult to machine, making it impractical.

Further, Co is 5%, W is 2%, and Cu and Mo are 0.
If the content exceeds 5%, the soft magnetic properties will be significantly deteriorated, making it impractical.

Furthermore, if the total amount of added elements other than Cr exceeds 6%, the soft magnetic properties will be significantly degraded, making it impractical.

Also, Ti, Co, Cu, Nb and Ta are 0.
Less than 1% W and Mo less than 0.2%, rare earth elements 0
,01, the effect of addition is not obvious.

Based on the above facts, the component ranges shown in the claims were determined.

The present invention will be explained in detail below based on examples.

Embodiment 1 FIG. 1 is a curve diagram showing the relationship between the tape sliding time and the amount of wear for a conventional sender toy and a typical example of the alloy opening C according to the present invention.

In the figure, curve A is conventional Sendust, and curve opening is Si8.2%-A15.5%- which is an embodiment of the present invention.
Cr5.4%-balance Fe, and curve C is another example of the present invention, Si & 5%-AI6.0%-Cr2-1%-
An ingot consisting of 0.7% Ti and the balance Fe was processed and then finished into a chip shape and measured.

As is clear from the figure, the alloy of the present invention has significantly improved wear resistance than the conventional material.

In other words, the wear amount of the tip after 20 hours of tape sliding is about 40 μm for the conventional material, whereas the wear amount for the alloy tip and the tip according to the embodiment of the present invention is 5.6 μm and 4.5 μm, respectively.
It can be seen that it has extremely excellent wear resistance.

Further, FIG. 2 shows a comparison between the relationship between the effective magnetic permeability μe and the frequency for the conventional sender toy and the alloy mouth according to the embodiment of the present invention.

As is clear from the figure, compared to the conventional Sendust, the alloy μe of the present invention is slightly smaller on the low frequency side, but shows almost the same value on the high frequency side, and has sufficiently good soft magnetic properties for practical use. I can see that you are there.

Example 2 Table 1 shows the compositions of other example alloys of the present invention.

Further, Table 2 shows the wear amount after 20 hours when the test was conducted in the same manner as in Example 1, the effective magnetic permeability at IKHz (plate thickness 0.3 mm), and the saturated magnetic flux density B100 value.

In Table 1, Sample No. 1 to 3 are conventional Sendust No.
, 4 to 32 are alloys of the present invention, while No. 4 to 6 are Fe alloys.
- When the 8i-A1 composition is kept constant and the amount of Cr added is changed, No. 7 to 25 is when the amount of Fe-8i-AI-Cr is kept constant and the type and amount of the second added element is changed, N
o, 26 to 28, the additive elements are constant, and Fe-8i-A
1 When the composition ratio is changed, No.

Nos. 29 to 32 show examples in which three types of additive elements are added in combination.

As can be seen from Tables 1 and 2, the wear amount of the alloy of the present invention is 3 to 22 μm, while that of conventional Sendust is 39 to 43 μm.
It has a significantly better value than μm.

Regarding μeIKHz, the alloy of the present invention has a lower value than the conventional alloy, but this is due to the fact that by adjusting the Fe-8i-A1 composition ratio, a value equal to or close to that of conventional sendust can be obtained. is possible.

As an example, cases in which 3.0% Cr and 0.3% Ti were added are shown in Nos. 23 and 27, but No. 270 μ5 IKHz, in which the main component composition was adjusted, shows values almost equivalent to conventional Sendust.

Furthermore, as shown in the examples, the alloy of the present invention has a value of Blo that is practically acceptable.

As described in detail above, the alloy according to the present invention not only has extremely excellent wear resistance (but also has magnetic properties comparable to conventional materials), and has extremely high industrial effects. big.

[Brief explanation of drawings]

FIG. 1 is a comparison diagram of the wear resistance of the alloy obtained according to the present invention and a conventional material, and FIG. 2 is a comparison diagram of frequency changes in effective magnetic permeability between the alloy obtained according to the present invention and the conventional material.

Claims (1)

[Claims] 1. A weight ratio of 12.5 to 8%, Si of 4 to 16%,
A wear-resistant high magnetic permeability alloy characterized by consisting of 0.2 to 15% Cr and the balance mainly Fe. 2 In terms of weight ratio, A12.5-8%, Si 4-16%,
The main components are CrO, 2 to 15%, the balance is Fe, and the subcomponents are o, i to 5% Ti, and 0.1 to 5% Co. 0.2 〃2 〃 Wl 0.01 〃l 〃 rare earth, 0.1 or more and less than 0.5% Cu. 0.1 〃0.2 〃 Nb. Ta1 of 0.1 〃0.2 〃 M of 0.2 〃0.5 〃. The total amount of one or more elements selected from the following is 0.
．． A wear-resistant high permeability alloy characterized by containing 0.01 to 6%.