JPH04228246A - Manufacture for fine crystalline and amordhous metallic strip and its producing device - Google Patents

Abstract

PURPOSE: To obtain an amorphous metal of a stable structure of microcrystals by a process in which molten made uniform is sent between force cooled metallic rolls, the cooling of the melt is stepwise regulatable and simultaneously an electric field acts between the rolls, then a magnetic field acts therebetween. CONSTITUTION: The melt having a prescribed chemical compsn. is sent into a crucible 1 and is sent to a homogeneizing device 2. The melt is sent, after holding for the prescribed time, between the rolls 5 past a nozzle 3 disposed in a microcrystal device 4 at a prescribed temp. and outflow velocity. A drive roll having a threaded turbine is previously rotated and cooled at a prescribed speed. Voltage U is impressed between the rolls 5 by a system 6 to ionize the melt. The stretched metal strip is sent to a cooling chamber 7 where the uniform magnetic field 8 acts on the strip during the cooling process. As a result, the amorphous metal of the stable structure of the microcrystals may be produced in the state of high reliability without environmental pollution.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method and apparatus for producing microcrystalline and amorphous metal strips, which have industrial applications in electrical engineering, electronics/microelectronics, general engineering and other fields. can be found.

0002

BACKGROUND OF THE INVENTION Methods for producing thin strips of limited thickness from 0.01 to 0.06 mm are known. In this method, the melt is directed from a nozzle onto the outer surface of a rotating metal disk. The melt spreads freely in the form of a strip of limited geometric dimensions and is cooled as a result of rapid heat transfer at the cooling surface. A device for separating the strips is in contact with the metal disk 1.

[0003] A device for carrying out this method comprises a thermal inductor and a nozzle for conveying the melt, which is provided in the inductor. Below the nozzle a metal disk is provided, which is in contact with a device for separating the produced strip 2.

The strips produced by this method and apparatus are heterogeneous, metastable, amorphous structures with limited geometric dimensions and unsatisfactory physical and mechanical properties.

In the known twin-roll process, the melt is passed through a nozzle between two metal rolls. This metal roll is rotating at high speed in the opposite direction. Cooling during the formation of the strip from the melt is achieved by induction of heat on the metal surface or by forcing water to flow along shaft cooling grooves in the circumference of both rolls 3.

The disadvantage of this known twin-roll method is that the microcrystalline structure of the strip produced is non-uniform and non-oriented;
Its physical and mechanical properties are not satisfactory.

A known twin roll device with forced cooling is provided with a crucible and a nozzle for feeding the melt below the crucible. Below the nozzle there is a horizontal roll with forced water cooling grooves arranged axially or at an angle. The melt falls between the rolls under its own weight. These rolls cool the molten metal strip 2
make.

The disadvantage of this known forced cooling twin roll device is that the grooved rolls for forced water cooling cannot ensure uniform heat induction, which may affect the quality of the produced strip. be.

[0009]

SUMMARY OF THE INVENTION Accordingly, it is a general object of the present invention to provide a method and an apparatus for manufacturing microcrystalline and amorphous metal strips, which It has a wide range of geometric dimensions and stability in microcrystalline and amorphous structures, resulting in improved physical and mechanical properties.

0010

This object is achieved by a method of transporting molten metal between rolls with forced cooling. During transport in the direction of the rolls, the melt is homogenized, the cooling of the melt is gradually and adjustable, and at the same time an electric field is applied to the melt between the rolls. After the forming and rolling steps on the melt, it is subjected to the action of a homogeneous magnetic field and, at the same time, an adjustable and defined cooling.

[0011] In one variant for the production of thin stable amorphous strips with a thickness of 0.01-0.07 mm, the homogenized melt is fed to the forming rolls, spreading freely over its surface and then their a second roll in the line of contact between the two rolls.

Another variant for the production of finely grained oriented metal strips with a thickness of 0.07 to 0.35 mm is to apply the homogenized melt vertically or against the line of contact between the two rolls. feed at an angle, then temperature T
>> At Tkr, a metal strip is simultaneously formed and rolled in an electric field with forced and adjustable defined cooling. The magnetic orientation of the metal strip is made under the action of a homogeneous magnetic field and with simultaneous adjustable cooling, the temperature being near the Curie point (T<Tkr).

The apparatus for carrying out this method is equipped with an induction crucible, a feed nozzle, and a forcedly cooled forming roll. A microcrystallizer with an induction homogenizer and a nozzle is provided between the crucible and the roll, a system for ionizing the melt is connected to the roll, and a magnetic "
It is equipped with a system for "orientation" and a chamber for adjustable cooling.

[0014]

The advantages of this method and apparatus are as follows.

This method provides good homogenization and uniform spreading of the melt, zonal forced cooling, and a thickness of 0.
．． Metal (especially magnetic) strips of 0.01 to 0.35 mm and width of 1 to 300 mm are simultaneously formed directly from the melt and rolled. The method is based on the zonal adjustment principle by direct action on the melt with electric and magnetic fields. As a result, microcrystalline and amorphous ferrostable
) properties of the magnetic strip with the structure are guaranteed. The rolling unit has small dimensions, large output,
It is characterized by low energy consumption and the possibility to adjust and control the roll and its attached systems according to preset programs. The equipment is light, inexpensive, takes up little space, and requires only a few units and elements. This device is adapted for the rapid reconditioning of rolls and systems for producing strips of different thicknesses of oriented microcrystalline or stable structure amorphous materials directly from the melt. It can also be operated reliably and in different conditions,
The method of the invention can be carried out without polluting the environment.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the invention, reference will now be made to the drawings, which illustrate preferred embodiments of the invention.

The rolling unit with two or four rolls is equipped with an induction crucible 1, an induction mixer (homogenizer) 2 placed on it, and jets and slots for wide strips below. A nozzle 3 is provided, and the nozzle is provided with a microcrystallization device 4 . Two drive rollers 5 and two support rollers 5a are provided below, and these are electrically insulated. A system 6 for ionizing the melt is connected to the driven insulating roller 5 . Below that, a cooling system 7 and a magnetic orientation system 8 are provided. At the end part there is a take-up winder 9, a heat treatment chamber 10 and an automatic welding unit 1.
1 is provided. It is also possible to incorporate a microprocessor system 12 to automate this process.

The operation of the twin roll device is as follows.

The melt having a predetermined chemical composition is placed in crucible 1.
and sent to the mixer (uniformizer) 2. There, it is held for a predetermined period of time. It then passes through a nozzle 3 provided in a microcrystallization device 4 and is sent between rolls 5 (or over one roll, respectively) at a predetermined temperature and outflow rate. In advance, a drive roll equipped with a screw turbine is rotated at a predetermined speed and cooled. A voltage U is applied between the rolls 5 by a system 6. This ionizes the melt at temperatures T>Tkr. The stretched metal strip is sent to the cooling chamber 7 at a temperature of approximately the Curie point (magnetic phase). A homogeneous magnetic field 8 acts on the strip during the cooling process. The produced strip is then automatically wound onto the take-up winder 9. Its speed is synchronized to the circumferential speed of the roller. Further, the strip is sent to a thermomagnetic processing chamber 10. And if necessary (when the strip breaks),
It is sent to the automatic welding unit 11. A microprocessor system 12 controls the apparatus with temperature, pressure, strip speed, and strip thickness detectors and transducers.

In experiments carried out with this apparatus, fine-crystalline, oriented structures and amorphous stable structures for ferromagnetic metal strips with a thickness of 0.02 to 0.07 mm were produced. The iron-based sample with (100) type microcubic structure had the following properties after being subjected to thermomechanical treatment. Magnetic loss at frequency f = 50Hz: ΔV (1.0) = 0
．． 32 = 0.4 W/kg; Magnetic induction for B25 = 1.7-1.8 T; Holding force of field: Hc = 0.21-0.24 Oe; Mechanical strength: Amome fas strip made by conventional method 100-200% higher compared to (without additional rolling in-situ); mechanical Vickers hardness: 10-15% higher compared to crystalline structure. References 1. U.S. Patent Specification No. 38815422. Glassy Metals I and II, Springer Berlag, Berlin/Heidelberg/New York, 1981 3. U.S. Patent Specification No. 3881541

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of the device of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Crucible, 2... Inductive homogenizer, 3... Nozzle, 4... Microcrystallizer, 5... Roll, 6... System for ionizing the melt, 7... Adjustable cooling chamber, 8... Magnetic " A system for providing direction.

Claims (5)

[Claims] 1. A method for producing microcrystalline and amorphous metal strips, in which molten metal is passed between forcedly cooled metal rolls, the melt is homogenized before being passed to the rolls, and the melt is Cooling is zonal
), which is adjustable and at the same time an electric field acts between the rolls and then a homogeneous magnetic field. 2. The method of claim 1, wherein the thickness is 0.
01 to 0.07 mm amorphous strips are made by feeding the homogeneous melt into a forming roll and spreading the melt over its surface, which is then rolled by a second roll located in the line of contact between them. The above method. 3. In the method of claim 1, the metal strip with an "oriented" microcrystalline structure and a width of 0.07 to 0.35 mm is used to direct the homogenized melt vertically or to the contact line of two rolls. The method described above is made by feeding at an angle to the temperature T>>Tkr and then forming and rolling it at a temperature T>>Tkr. 4. The method according to claim 1, wherein the magnetic "orientation" of the metal strip is adjustable under the action of a uniform magnetic field and at a temperature near the Curie point (T<Tkr). The above method brought about by cooling. 5. An apparatus for carrying out the method according to claim 1, comprising an induction crucible, a melt discharge nozzle, and a forcedly cooled forming roll, and an induction homogenizing device 2 and a nozzle between the crucible 1 and the roll 5. A microcrystallization device 4 is provided with 3 and connected to the rolls a system 6 for ionizing the melt, below which a system 8 for magnetic "orientation" and a chamber 7 for adjustable cooling are provided. The above equipment.