JPS5857260B2 - Method for manufacturing ribbon-shaped sendust alloy - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a thin ribbon-shaped Sendust alloy directly from a Sendust alloy in a molten state.

Currently Si3.0-13.0%, A43.0-10.0%
and the balance Fe-8i-Al! V, Nb, and Ta are added to this for the purpose of improving alloy (sendust) or magnetic and mechanical properties.

Cr, Mo, W', Ni, Co, Cu, Ti
, Mn.

Ge Zr, Sb, Sn, Be, B, Bi, Pb.

Total of 7.0 of one or more types of tsuY, rare earth elements, etc.
Sendust-based alloys with a loading of less than % have excellent magnetic properties and high hardness, resulting in good wear resistance, and are used as cores for magnetic heads for magnetic recording and magnetic recording (VTR).

However, although Sendust alloys have high hardness, they are extremely brittle.
Because forging and rolling are difficult, the thin plate-shaped core that makes up the magnetic head is manufactured by cutting the ingot, but small racks and chips occur during manufacturing. As a result, the yield of finished products is low, which is a big problem.

Therefore, if there is a method for easily producing thin ribbon-shaped sendust alloys without the difficulties encountered in mechanical processing, it would be possible to produce thin plate-shaped cores at high yields and at low cost.

The present invention is a method for producing a thin ribbon-shaped sendust alloy that does not involve mechanical processing, and aims to produce a sendust-based alloy that is directly cooled and solidified into a thin ribbon shape from a molten state. As a result of numerous studies, we have found that the most suitable method is to eject the sendust alloy melted in a crucible onto the surface of a cooling body rotating in a constant direction from the nozzle, and cool and solidify it into a thin ribbon shape.

The rotary cooling body in this case is, for example, two roll surfaces of a two-high rolling mill made of metal or refractory, the inner or outer surface of one rotating cylinder, or the surface or side surface of one rotating disk. .

According to this manufacturing method, by appropriately adjusting the composition of the molten alloy, the temperature, the shape and size of the jet nozzle, the jet speed, the material and size of the rotary cooling body, the rotation speed, the roll gap, etc., it is relatively easy to produce. It is possible to produce long ribbon-shaped sendust alloys.

In other words, if the rotating body is a roll, the jet nozzle is not affected by its shape, but if it is a disk or cylinder, it is preferable to have a rectangular shape in order to solidify into a ribbon shape, and generally the size is preferably 207n7IL2 or less. .

Although the temperature of the molten metal depends on the alloy composition, it is generally preferable to range from the melting point to 200°C.

The ejection velocity from the nozzle is desirably higher when the linear velocity change of the rotating body is large, but generally it is preferably 3 m/sec or more, and the linear velocity of the rotating body receiving the molten alloy is preferably 1 m/sec or more.

Further, since the width of the roll gap determines the thickness of the ribbon, it is necessary to determine the width according to the thickness, but it is generally 5 mm or less.

An example embodiment of the present invention will be described below.

Example l A quartz tube was filled with an alloy consisting of 84.5% Fe, 0% 5ilO, and 15.5% A, and the mixture was heated for 15% in an argon gas atmosphere.
Melt it by heating to 30℃ and use a rectangular nozzle spout (0.2X
3. Omm
A copper disk (diameter 1
0 crrL1 thickness 1 cm) by spouting on the surface of 4 yen from the upper middle of the width 10 m 71 t, thickness 0.
An alloy solidified in the form of a uniform ribbon with a size of 15 mm and a length of 3 m was obtained.

From this, an annular plate with an outer diameter of 81n1rt and an inner diameter of 4mm was manufactured, heated in hydrogen at 1000℃ for 2 hours, and then cooled in a furnace.The effective magnetic permeability at 100KIIz was 950, and the amount of wear as a magnetic herad core was 2 γ-Fe203 tapes
The amount of core wear after 00 hours was 12 Iirn, which was extremely superior to the effective magnetic permeability of 900 and core wear amount of 1.5 μm when manufactured from an ingot as in the conventional method.

Example 2 A quartz tube was filled with an alloy consisting of 15%, heated to 7JO at 1550°C in an alcohol gas atmosphere, and ejected from a circular nozzle (diameter 0.5 mm) at a speed of about 45 m/sec.
Copper cylinder with rotation speed 350 OR, PN (inner diameter 10 CTL)
), the width is 8 mm and the thickness is 0.1 mm.
An alloy solidified into a dimensionally uniform ribbon having a length of 2 mm and a length of 2771 mm was obtained.

From this, a circular plate with an outer diameter of 8 mm and an inner diameter of 4 mm was manufactured, and 1
When heated in hydrogen at 050°C for 1 hour and then cooled in the furnace, 10
The effective magnetic permeability at 0 KHz is 1170, and the amount of wear as a magnetic helad core is 26 μm when a CrO2 tape is worn for 200 hours.The effective permeability when manufactured from an ingot using the conventional method is 1150 and the amount of core wear is 2. .8
Compared to μm, the one of the present invention showed superior characteristics.

Example 3 Fe84.0%, Si9.0%, Al1.0%, 710
A quartz tube was filled with an alloy consisting of %, TiO, 8%, and ZrO 2%, heated and melted at 1580°C in an argon gas atmosphere, and ejected from a circular nozzle (diameter 0.7 mm) at a speed of approximately 40 m/sec. By ejecting water into the gap of 0.1 mm between two opposing cast iron rolls with a roll diameter of 5 CrrL rotating at a rotational speed of 300 ORPM, a radius of 11
An alloy solidified into a bong-like shape with uniform dimensions was obtained, with a thickness Q of 0.1 mm and a length of 5 m.

From this, I made an annular plate with an outer diameter of 8 mm and an inner diameter of 4 mm.
When heated in hydrogen at 00℃ for 1 hour and then cooled in the furnace, 10
The effective magnetic permeability at 0 Ktlz is 1220, and the amount of wear as a magnetic helad core is 13 μm when a Cr 02 tape is worn for 200 hours. 1
．． Compared to 5 μm, the one of the present invention showed excellent characteristics.

In short, the manufacturing method of the present invention is suitable for mass-producing continuous long ribbon-shaped sendust alloys at low cost by selecting optimal conditions corresponding to the composition of the alloy as described above.

Ribbon-shaped Sendust alloys made by this method do not have pinholes, cracks, etc. unlike ingots, and have excellent magnetic properties and wear resistance as well as ingots. It is very suitable as a magnetic alloy for recording and reproduction.

Claims (1)

[Scope of Claims] 1. Sendust which is cooled and solidified in a ribbon shape by spouting a sendust-based alloy melted in a crucible from its nozzle onto the surface of a cooling body that moves in a constant direction at a speed of ITL/second or more. A method for producing a sendust-based alloy, characterized by obtaining a sendust-based alloy. 2. The "surface of a cooling body that moves in a fixed direction at a speed of 1 m/sec or more" as stated in claim 1 has a linear velocity of 1 m.
A method of obtaining a sendust-based alloy that is solidified in a ribbon shape by ejecting it onto the surface or side surface of a rotating disk at a speed of 4 seconds or more. 3% The "surface of a cooling body that moves in a constant direction at a speed of 1 m/sec or more" stated in claim 1 has a linear velocity of 17
This is the inner or outer surface of a cylinder that rotates at a speed of 71/sec or more, and a method of obtaining a sendust-based alloy that is cooled and solidified in a ribbon shape by jetting molten alloy onto this surface. 4. The "surface of a 4-plane body that moves in a constant direction at a speed of 1 m/sec or more" stated in claim 1 is the linear velocity If.
Two roll surfaces of a rolling mill for 1 m 7 seconds or more,
A method of obtaining a sendust alloy that is cooled and solidified in a ribbon shape by jetting the molten alloy onto the surface.