JPS5867845A - High permeability alloy thin strip - Google Patents

Abstract

PURPOSE:To obtain a high permeability alloy thin strip having extremely easy processability such as machine punching processing by employing a molten metal rapid cooling method, by adding Cr, Mo, W, Mn and Co to an Fe-Si-Al high permeability alloy in a proper amount. CONSTITUTION:An alloy consisting of, on the wt. basis, 4-12% Si, 2-9% Al, 0.05-7% combined amount of one or more of Cr, Mo, W, Mn and Co and the remainder of substantially Fe is melted under heating and injected onto the surface of a cooling body moving at a high speed and solidified thereon to obtain a thin strip. The resulting thin strip is excellent in bending property (tenacity) compared to a conventional Fe-Si-Al alloy as well as a wide thin strip is easily obtained from said alloy. In this case, when the addition amount of an element such as Cr or the like is below the lower limit, adding effect is not developed remarkably and, when above the upper limit, magnetic characteristics are deteriorated to a large extent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in Fe-8i-At based high magnetic permeability alloy ribbons.

The Fe-8i-Al alloy has approximately 9.5% 8i and A
t is about 5.6 Yu.

In 1956, Masan et al. found that a composition with the remainder mainly consisting of Fe can provide a significant magnetic permeability and a large saturation magnetic flux density B1 (magnetic flux density at an applied magnetic field of 100 C).
It was discovered in the year. Since the above-mentioned alloy has hard and brittle properties and easily becomes powder, it was primarily used as a dust core as an inductance element at the time of the invention.

Meanwhile, advances in magnetic recording technology have been remarkable in recent years.
The coercive force of magnetic tape, a magnetic recording medium, is rapidly increasing for the purpose of increasing recording density or improving sound quality, and in the audio field, the coercive force of magnetic tape is rapidly increasing.
F60. This led to the emergence of metal chips with a coercive force two to three times that of tape. In order to fully exploit the performance of a magnetic tape having such a large coercive force, the core material of the magnetic head must have high magnetic permeability and a high saturation magnetic flux density B1. For this reason, permalloy (B, = 45-8.0T) and ferrite (B,
Fe with large BIG compared to @=4.0~s,sT)
-8i -At-based alloys suddenly came into the spotlight.

However, as mentioned above, the Fe-8i-At alloy is hard and brittle, making it extremely difficult to roll, and the general method is to form the magnetic head core from a cast ingot by machining such as cutting and grinding. It is taken. However, since metallic core materials have a low electrical resistivity, when used as an electromagnetic transducer at high frequencies, their effective magnetic permeability tends to decrease due to eddy current loss. Therefore, the metal core material is generally used in the form of a thin plate in order to maintain a high effective magnetic permeability even at high frequencies. Normally, for audio use, 2 plates with a thickness of 0.1 to 0.5 are used.
~6 sheets are stacked and used. This is because Fe-8i-At alloys are extremely difficult to roll.

It is necessary to finish it into a thin plate by machining such as cutting and grinding, which is a major disadvantage compared to permalloy, which can easily be made into a thin plate by rolling.

Various manufacturing methods have been tried to solve the above-mentioned problems of Fe-8i-At alloys, but among them, the molten metal quenching method is capable of obtaining a ribbon of about 2.0 to 100 μm directly from the molten metal. This is one of the most practical methods. Regarding these manufacturing methods, please refer to Japanese Patent Application Laid-Open No. 51-158517.
．． # It has been proposed in 1972-125314 etc. In other words, the molten metal quenching method is a method in which the molten metal is jetted onto the surface of a rapidly moving cooling body through a nozzle to obtain a ribbon, but the Fe-8i-A4 alloy ribbon obtained by this method is subject to some degree of deformation. However, because the core is hard and brittle, it is extremely difficult to produce a magnetic rad core by mechanical punching. In other words, even if the Fe-8i-A1 alloy ribbon is made by the molten metal quenching method, it requires many more steps than mechanical punching, such as cutting and grinding to make the head core. There was a big problem in that it had to depend on the processing method.

The present invention aims to improve the above-mentioned problems of Fe-8t-A based alloy ribbons and to provide Fe-8i-AL based alloy ribbons that can be easily machined such as machine punching. . In other words, the l amount ratio is 8i4~12%, At2~
9%.

(Contains a total of 0.03 to 5 of one or more selected from r, Mo, W, Mn and Co,
Fe obtained by ejecting a molten body, the remainder of which is essentially Fe, onto the surface of a cooling body moving at high speed and solidifying it.
The -8i-AL alloy ribbon can be easily processed by mechanical punching, etc., without significantly impairing the magnetic properties inherent to the Fe-8i-A1 alloy ribbon. Furthermore, the alloy ribbon of the present invention has excellent bendability (initial strength) and is easy to obtain a wide ribbon as compared to the conventional Fe-8i-A1 alloy ribbon.

In the present invention, the amount of Si is 4 to 12%, and the amount of At is 2 to 9%.
The reason why it is set as % is that magnetic properties have a practically sufficient value within the above composition range depending on the amount of added elements. Also Cr.

The total amount of Mo, W, Mn and Co added is
The reason why K is set at 5 to 7 ts is that if the K is less than 0.05, the effect of addition is not significant, and if it is more than 5 ts, the magnetic properties will be significantly deteriorated, so that neither K is practical.

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

Example Electrolytic iron (99% purity), metallic silicon (99% purity).

Aluminum (purity q 9. tp 9 qb) and each additive element were weighed to a predetermined component ratio so that the total amount was 500 gr, then melted in a high frequency vacuum melting furnace and blown up into a molten quartz tube. A master alloy of 'X70' was prepared.The obtained master alloy was put into a quartz tube nozzle and heated and melted in an Ar air flow.
Bath water was jetted near the contact area of two steel rolls that rotated in contact with each other at an appropriate rotational speed of ~11,000 rpm to obtain a thin strip having a thickness of 55 μm and a width of 1 ollIII. The obtained ribbon was heat-treated for 1 hour at an appropriate temperature of 650 to 5 soc in an inert gas for the purpose of removing thermal distortion.

The mechanical punchability test was conducted by punching out a 7-by-7 square plate using a mechanical press. For the evaluation of punching properties, 200 square plates were punched out for each composition, and the resulting plates were observed at 20x magnification.
The hammers were classified into five categories: genuine (original), those with a chipped corner, and those that were damaged, and evaluations were made based on the number of each type. Further, as a magnetic measurement sample, 8° x 4 toroidal cores were prepared from each ribbon, magnetically annealed at aoo°C for 1 hour, and then subjected to magnetic measurement. Table 1 shows the composition of the sample, and Table 2 shows the evaluation results of mechanical punchability and magnetic properties.

As is clear from Table 1 and Table 2, in the samples with the same Fe-8i-At composition ratio, Cr and Mo, which are the materials of the present invention.

Claims (1)

[Claims] Weight ratio Si4~12% + AZ 2~9qb# Cr
I Mo + W + 1 selected from Mn and Co
Fe characterized by heating and melting an alloy containing Q, 05 to 7 species or two or more species in total, the remainder consisting essentially of Fe, and then ejecting it onto the surface of a cooling body moving at high speed and solidifying it. -S i -At-based high magnetic permeability alloy ribbon.