JPH10263761A - Nozzle for manufacturing rapidly solidified thin strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily observe the whole paddle to be formed in a gap between a nozzle and a roll through the injection of the molten metal by inclining at least one of bottom surfaces of a nozzle wall on each side of an opening part of the nozzle inward of the nozzle. SOLUTION: A nozzle 13 injects the molten metal 2 from an opening part in a bottom surface onto the surface of a rotating roll 4 with the axial direction of a roll as the width direction, and forms a paddle 1 between the opening part and the roll 4. At least one bottom surface of a nozzle wall 3 on each side of the opening part in the width direction of the nozzle 13 is an inclined surface 13B which is inclined inward of the nozzle 13. The angle of inclination formed by the inclined surface 13B relative to the opening part is θ, and the distance between two lines formed by intersection of the horizontal plane in contact with an upper surface of the roll 4 and the plane of extension of the inclined surface 13B with the viewpoint installation surface 5 with the distance L of observation from the width end of the paddle 1, is (h), and θ, h, L, and the gap (g) between the nozzle and the roll are in the geometrical relationship of h=g+Ltanθ. θ is preferably >=tan<-1> (5/L).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle for producing a quenched ribbon and a method and an apparatus for producing a ribbon using the nozzle. More specifically, the present invention relates to a method for moving a molten metal (including an alloy) of a metal (including an alloy). For producing a quenched ribbon used for continuously producing an amorphous or crystalline metal ribbon, and a method and apparatus for producing a ribbon using the nozzle. About.

[0002]

2. Description of the Related Art A method for continuously producing (casting) a ribbon having a desired thickness directly from a molten metal has conventionally been a centrifugal casting method,
Various means, such as a single roll method and a twin roll method, are disclosed. In each case, a molten metal (a roll or a drum) facing a nozzle opening under a predetermined pressure from a nozzle having a predetermined shape. ) Is solidified by injection solidification on the surface.

For example, in the single-roll method, the bottom surface of a nozzle having one or more slit-shaped or hole-shaped openings through which molten metal passes is brought close to the surface of a rotating cooling roll (the nozzle / roll gap is usually 1mm or less)
By injecting molten metal, a paddle (puddle) is formed between the opening and the surface of the cooling roll as a casting start point of the ribbon, and the solidified layer at the bottom of the paddle that grows sequentially on the roll surface is rotated. The ribbon is continuously obtained by taking it out of the paddle.

[0004] Important manufacturing factors governing the properties of the ribbon (surface roughness, thickness uniformity, etc.) are the shape of the nozzle (especially the opening), the relative arrangement between the nozzle and the cooling roll surface (nozzle / roll). Gap, injection angle, etc.), injection pressure of the molten metal from the nozzle, and the moving speed of the chill roll surface.
JP-A-60-108144, JP-A-61-63346, JP-A-61-1
54737, JP-A-61-159246, JP-A 2-3425
There are a number of conventional techniques disclosed in Japanese Patent Application Laid-Open No. 9,275-254254, Japanese Patent Application Laid-Open No. 5-245598, Japanese Patent Publication No. 5-23864, and the like.

[0005]

In the single roll method, it is important to keep the paddle at an appropriate size between the nozzle bottom surface and the cooling roll surface. If the paddle is too large, the thickness of the ribbon becomes thicker than the target thickness, and paddle breaks are likely to occur. On the other hand, if the paddle is too small, the ribbon thickness becomes thinner than the target thickness, and nozzle clogging tends to occur.

[0006] The size of the paddle (particularly, the cross-sectional size in the casting direction) changes sensitively due to fluctuations in factors that are difficult to directly control, such as the temperature, viscosity, surface tension, and internal pressure of the paddle itself. , While directly observing and monitoring the paddle (hereinafter collectively referred to as "observation"), quickly adjust the nozzle / roll gap and injection pressure based on raw information on its size (the melt temperature and nozzle shape are It is considered that it is effective to change the roll speed because it cannot be changed.

Nevertheless, the above-mentioned prior art relating to the nozzle shape only proposes the shape, size or number and arrangement of nozzle openings suitable for stably maintaining the paddle size within an appropriate range. Nothing suggests a nozzle shape suitable for observation. Moreover, even if it is attempted to observe the paddle based on the above idea, it is extremely difficult to observe the entire height of the paddle with a nozzle having a conventionally disclosed shape. The reason will be described with reference to FIG.

FIG. 7 shows an example of a state of manufacturing a ribbon using a conventional nozzle. FIG. 7A is a cross-sectional view in which the direction of casting is from the front to the back of the paper, and FIGS. FIG. In FIG. 7, 1 is a paddle (water pool),
Reference numeral 2 denotes a molten metal (molten metal), 3 denotes a nozzle wall, 4 denotes a roll (cooling roll), 5 denotes a viewpoint installation surface spaced apart from a paddle width end having a roll axis direction by an observation distance L in a width direction, and 6 denotes a viewpoint installation surface. Reference numeral 13 denotes a nozzle (a nozzle for manufacturing a rapidly cooled thin ribbon).

As shown in FIG. 1, when the paddle 1 is viewed from a viewpoint B in a viewpoint setting surface 5, an upper portion of the paddle 1 has a nozzle wall 3.
When viewed from the viewpoint D, the lower part of the paddle 1 is hidden by the roll 4 (d). The entire height of the paddle 1 can be observed only when viewed from the viewpoint C within a range equal to the extremely small gap g between the nozzle and the roll, usually 1 mm or less (c).

Since the range of observable positions where the entire paddle height can be observed is extremely narrow in this way, it is very difficult to install an observation camera, and even if it can be installed, there is vibration during manufacture of the ribbon. And the position of the camera is likely to be out of the observable range. Therefore, in the conventional ribbon production, even if the temperature, viscosity, surface tension, and internal pressure of the paddle itself are out of the appropriate ranges and the paddle becomes excessively large or small due to an accidental cause, the paddle itself is not noticed, Problems such as unevenness, paddle breaks, and clogged nozzles were inevitable.

Accordingly, the present invention provides a quenching device which is capable of easily observing the entire paddle formed in the gap between the nozzle and the roll by the molten metal injected through the nozzle onto the surface of the rotating chill roll during the production of the quenched ribbon. An object of the present invention is to provide a nozzle for manufacturing a ribbon so that a paddle size can be directly grasped. The present invention also provides a method and an apparatus for manufacturing a ribbon capable of promptly reflecting paddle observation results obtained at the time of manufacturing a ribbon using the nozzle of the present invention in the manufacturing conditions of the ribbon. It is an object of the present invention to be able to manufacture a thin ribbon and to avoid occurrence of troubles such as paddle break and nozzle clogging.

[0012]

According to a first aspect of the present invention, a molten metal is injected into the surface of a rotating roll from the opening at the nozzle bottom with the axial direction of the roll as the width direction, and the opening and the roll are rotated. A quenched ribbon manufacturing nozzle that forms a paddle with the surface of the nozzle, wherein at least one bottom surface of the nozzle wall on both sides of the opening in the width direction is an inclined surface inclined toward the inside of the nozzle. This is a nozzle for manufacturing quenched ribbons.

In the present invention, the inclination angle θ of the inclined surface is set to tan ⁻¹ (5/5) according to the observation distance L (mm) to the paddle width end.
L) It is preferable that the angle is equal to or more than 45 °, and it is preferable that the angle is equal to or less than 45 °. Further, a second invention is a method for manufacturing a ribbon using the nozzle of the first invention, wherein the paddle is observed through a space between the inclined surface and the surface of the roll at the time of manufacturing the ribbon. Then, based on the observation result, at least one of the gap between the nozzle / roll and the injection pressure is controlled so as to keep the size of the paddle within a predetermined range.

According to a third aspect of the present invention, there is provided a roll, a rotating device for rotating the roll, a nozzle for injecting the molten metal onto the roll surface, an intermediate container for storing the molten metal passed through the nozzle, and an intermediate container. An apparatus for manufacturing a ribbon, comprising a lifting device for raising and lowering, a melting furnace for feeding the molten metal to the intermediate container, and a valve device for changing a feeding amount of the molten metal from the melting furnace to the intermediate container. A paddle observation camera; and a nozzle / pad for analyzing a paddle image obtained by the camera to derive a current size of the paddle and reducing a deviation between the current size and a predetermined size to zero.
An image analyzer that calculates the values g ₀ and P ₀ of the gap between the rolls and the injection pressure, and the current value of the gap between the nozzle and the roll is g
₀ and elevation control device for driving the lifting device so as to coincide, the ribbon, characterized in that the current value of the injection pressure and a valve control device for driving the valve device so as to coincide with P ₀ Manufacturing equipment.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1A and 1B show an example of a ribbon production state using a nozzle according to the present invention. FIG. 1A is a cross-sectional view in which the direction of casting is from the front to the back of the paper, and FIG. It is a B arrow view of a). In FIG. 1, reference numeral 13B denotes an inclined surface, and the same or corresponding portions as those in the conventional example of FIG. 7 are denoted by the same reference numerals, and description thereof will be omitted.

As shown in this figure, the nozzle 13 of the present invention (first present invention) is configured such that the melt 2
In the quenched ribbon manufacturing nozzle 13 which forms the paddle 1 between the opening and the surface of the roll 4 by injection, at least one bottom surface of the nozzle wall 3 on both sides of the opening in the width direction is a nozzle. The gist of the present invention is that the inclined surface 13B is inclined toward the inside. In FIG. 1, θ is the inclined surface 13B.
Is the angle of inclination formed by the opening (including a plane), and h is the horizontal plane in contact with the upper surface of the roll 4 and the extension surface of the inclined surface 13B.
The distance between two straight lines formed by intersecting the width end of the paddle 1 and the viewpoint installation surface 5 where the observation distance L is set, and θ, h, L, and the gap g between the nozzle and the roll are given by the following equation: h = g + L tan θ Are in a relationship.

With this configuration, the observable range of the entire height of the paddle 1 within the viewpoint setting plane 5 is the same as that of the conventional g shown in FIG.
From FIG. 1 (a), if it is enlarged to h (h> g), and if the viewpoint B is provided within the enlarged observable range, FIG.
Therefore, according to the first aspect of the present invention, the conventional difficulty relating to the paddle observation can be greatly reduced.

The inclination angle θ of the inclined surface 13B is tan ⁻¹ (5 / L) ° according to the observation distance L (mm) to the width end of the paddle 1.
Preferably, the angle is not less than 45 °. If θ <tan ⁻¹ (5 / L) °, h is less than (5 + g) mm from the above geometrical relationship, and g is usually as small as 1 mm or less as described above, so that the observable range is too narrow. . On the other hand, if θ> 45 °, as shown in FIG. 2, the paddle break 7 is likely to occur from the width end of the paddle 1 on the observation side. In FIG. 2, the same or corresponding parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

Strip casting in which the above preferred range of the inclination angle θ is determined.
The experimental results are described below. In the form shown in FIG.
With an opening (0.7mm x 20mm slit) on the short side of the opening
The nozzle 13 made of quartz having a thickness of 5 mm on the side of the nozzle wall 3 is
G = 0.25mm, opening on top of cooling roll 4 made of -Be alloy
Set the long side (paddle 1 width direction) parallel to the roll axis direction
Do not rotate the cooling roll 4 at a roll peripheral speed of 30 m / s.
Gara, Fe₇₈Si ₉B₁₃Of alloys of different compositions (subscripts are at%)
Injection pressure of hot water 2 through nozzle 13 from opening to roll surface
0.1kgf / cm^TwoInjected with a thin ribbon of amorphous alloy 6 (22μ thick)
In casting m), the nose on one short side of the opening
The bottom of the wall 3 is inclined at θ = 0 °, 1 °, 3 °, 10 °, 45
°, 50 °, 60 ° using a nozzle 13 with an inclined surface 13B
Five castings per nozzle were performed. At this time, the slope 13
Viewing point at observation distance L = 100mm from paddle 1 width end on side B
An observation camera is installed at the viewpoint in plane 5 and one side of paddle is
Observation, difficulty of paddle 1 height observation and paddle bray
Incidence rate (paddle break out of 5 castings per nozzle)
As a result of examining the number of occurrences of
And θ <3 ° (≒ tan^-1(5/100) °) difficult to observe
When θ> 45 °, the paddle break
However, when θ = 3 ° to 45 °, observation is easy and paddle blur
There was no workout.

According to a second aspect of the present invention, there is provided a method of manufacturing a ribbon using the nozzle according to the first aspect of the present invention, wherein the ribbon is passed through a space between the inclined surface and the surface of the roll when the ribbon is manufactured. The gist is to observe the paddle and to control at least one of the nozzle / roll gap and the injection pressure so as to keep the size of the paddle within a predetermined range based on the observation result. As a result, the temperature, viscosity, surface tension and internal pressure of the paddle itself fluctuate due to accidental causes, resulting in an excessive paddle,
Even if the size is to be reduced, the paddle size can be quickly corrected, so that uneven thickness of the ribbon, paddle breaks and nozzle clogging can be effectively avoided, and stable production of quench ribbons of uniform quality can be stably produced. It becomes possible.

The size of the paddle is preferably the length in the casting direction. The height position at which the length in the casting direction is measured must be the contact position between the paddle and the roll, and one or more other measurement height positions may be provided. A third aspect of the present invention is a thin ribbon manufacturing apparatus suitable for implementing the second aspect of the present invention, comprising: a roll; a rotating device for rotating the roll; and a nozzle for injecting a molten metal onto the roll surface.
An intermediate container for storing the molten metal passing through the nozzle, an elevating device for raising and lowering the intermediate container, a melting furnace for feeding the molten metal to the intermediate container, and a valve device for changing a feed amount of the molten metal from the melting furnace to the intermediate container Wherein the nozzle is the nozzle of the first aspect of the present invention, and further, a paddle observation camera, and a paddle image by the camera are analyzed to derive a current size of the paddle. A nozzle / roll gap (hereinafter abbreviated as a gap) that calculates the deviation between the size and the predetermined size to be zero, an image analyzer that calculates the values g ₀ and P ₀ of the injection pressure, and the current value of the gap as g _The gist of the present invention is to provide a lifting control device that drives the lifting device so as to make the same ₀ , and a valve control device that drives the valve device so that the current value of the injection pressure matches P0.

FIG. 4 is a schematic diagram showing a third example of the present invention. The molten metal 2 is injected from the opening at the bottom of the nozzle 13 onto the surface of the roll (cooling roll) 4 rotated by a rotating device (not shown), and the ribbon 6 is being manufactured. This nozzle 13
Is a nozzle of the first aspect of the present invention. In this example, the bottom surface on both outer sides of the opening width is an inclined surface, but only one side on the paddle observation side may be an inclined surface.

The inlet side of the nozzle 13 is connected to a pouring port (tundish pouring port) 19 at the bottom of the tundish (intermediate container) 14, and the molten steel 2 is stored in the tundish 14 at a predetermined level. I have. By changing the level of the molten metal, the static pressure of the molten metal, that is, the injection pressure is adjusted. In addition, the tundish 14 can be moved up and down by an elevating device 10D to adjust the gap.

Above the tundish 14, a melting furnace 16 is disposed, and the melting furnace 16 melts a metal or alloy material to form a molten metal 2 and feeds it to the tundish 14 as needed. The molten metal feed path is such that a nozzle 15 between the melting furnace and the tundish is connected to a pouring port (melting furnace pouring port) 18 at the bottom of the melting furnace 16. The opening of the melting furnace pouring port 18 can be adjusted by a stopper rod 17 whose upper end is supported by a valve device 12D so as to be able to move up and down.
It is configured to change the level of the molten metal 2 in the inside 14.

Next, regarding the observation and control system, first, a camera (paddle observation camera) 8 is installed at a viewpoint within a viewpoint installation plane 5 which is at an observation distance L from the end of the paddle width. Camera 8
As such, a CCD camera is preferable. The paddle image taken by the camera 8 is input to the image analysis device 9. The image analysis device 9 analyzes the input paddle image to derive the current size of the paddle, and sets the values g ₀ , P of the gap and the injection pressure so as to make the deviation between the current size and the predetermined size zero.
₀ is calculated, and g ₀ is sent to the elevation controller 10 and P ₀ is sent to the valve controller 12. The elevation control device 10 drives the elevation device 10D so that the current value g of the gap coincides with g ₀ , and the valve control device 12 controls the valve so that the current value P of the injection pressure coincides with P _0. The device 12D is driven.

The lift control device 10 itself can recognize g, and the tundish weight is detected by the tundish weight detecting device 11 for P, and P is calculated from the detected value and sent to the valve control device 12. . Thereby, the second invention can be efficiently implemented. The predetermined size (appropriate size) of the paddle can be determined by preliminary experiments, but it can also be determined by quickly analyzing observation data at the beginning of casting for each casting. In using this device, both the elevation control device 10 and the valve control device 12 can be used, but if only one of them is sufficient, only one of them may be used.

Although not shown, it is also possible to construct a control system that takes into account the roll peripheral speed in addition to the gap g and the injection pressure P as the operation amounts.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the apparatus configuration shown in FIG. 3, an opening (0.
7 mm x 50 mm slit), and a silicon nitride nozzle 13 having a bottom surface on both short sides of the opening with an inclined surface having an inclination angle θ of 10 °
Is arranged above the cooling roll 4 made of a Cu-Be alloy with an initial gap g = 0.25 mm and the long side of the opening (paddle width direction) is parallel to the roll axis direction. While rotating at s, a melt 2 of about 100 kg of alloy having a composition of Fe ₇₈ Si ₉ B ₁₃ (subscript is at%) is injected through the nozzle 13 to the roll surface from the opening at an injection pressure of 0.1 kgf / cm ^2. In casting the amorphous ribbon 6, the paddle observation camera 8 is installed at the viewpoint within the viewpoint installation surface 5 at an observation distance L = 200 mm from the edge of the paddle, and the paddle is photographed. The paddle size (using the length of the paddle bottom in the casting direction) is read using the automatic analysis control program installed in the image processing device 9 and compared with an appropriate size stored in advance. calculates the value g ₀ of the gap such that the zero, Descending controller 10, the current g as causative lifting device 10D was as in Example performs automatic control to match the g _0.

On the other hand, a thin strip was cast under the same casting conditions as above using a conventional nozzle in which the bottom surface on the paddle observation side was not inclined (θ = 0 °). In the conventional example, paddle observation was not possible, so automatic control was not performed, and the initial gap g =
After holding 0.25 mm for 5 seconds, the gap was reduced at 0.01 mm / s, and when the gap reached 0.20 mm, the gap was kept constant. FIG. 5 shows the temporal change of the paddle size, the nozzle / roll gap, and the ribbon thickness of the embodiment, and FIG. 6 shows the temporal change of the nozzle / roll gap, the ribbon thickness of the conventional example. The thickness of the collected ribbon was measured at three locations (width center, 1/4 width, both sides) with a micrometer every 60 m in the longitudinal direction (every 2 seconds), and the three-point average at each time was plotted.

FIG. 6 shows that the thickness of the ribbon in the conventional example varied greatly in the casting direction. However, from FIG. 5, the thickness of the ribbon in the embodiment became substantially constant in the casting direction. Could be transformed. Not disclosed in this embodiment, when only the valve control device 12 is used, and when both the elevation control device 10 and the valve control device 12 are used, the thickness is as uniform as in this embodiment. Was obtained.

[0031]

According to the present invention, the entire paddle formed in the gap between the nozzle and the roll by the molten metal injected through the nozzle onto the surface of the rotating cooling roll can be easily observed during the production of the quenched ribbon. Furthermore, since the paddle observation results can be promptly reflected in the manufacturing conditions of the ribbon, it is possible to produce a ribbon having a uniform thickness in the casting direction and eliminate the problems of paddle breaks and nozzle clogging. Play.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing an example of a production state of a ribbon using a nozzle of the present invention, in which FIG. 1A is a cross-sectional view in which the casting direction is from the front to the back of the paper, and FIG. It is.

FIG. 2 is a cross-sectional view showing a situation where a paddle break occurs.

FIG. 3 is a graph showing a relationship between a tilt angle θ, paddle observation difficulty, and a paddle break occurrence rate.

FIG. 4 is a schematic diagram showing a third example of the present invention.

FIG. 5 is a graph showing changes with time in paddle size, nozzle / roll gap, and ribbon thickness in the example.

FIG. 6 is a graph showing a change with time of a gap between a nozzle and a roll and a thickness of a ribbon in a conventional example.

7 (a) is a cross-sectional view showing an example of a state of manufacturing a ribbon using a conventional nozzle, in which the direction of casting is from the front to the back of the paper, and FIGS. 7 (b) to (d) are B in FIG. 7 (a). FIG.

[Explanation of symbols]

 1 Paddle (pool) 2 Molten metal (molten metal) 3 Nozzle wall 4 Roll (cooling roll) 5 Viewing surface 6 Thin strip (quickly cooling strip) 7 Paddle break 8 Camera (paddle observation camera) 9 Image analyzer 10 Elevating Control device 10D Lifting device 11 Tundish weight detection device 12 Valve control device 12D valve device 13 Nozzle (nozzle for quenching ribbon production) 13B Inclined surface 14 Tundish (intermediate container) 15 Melting furnace / tundish nozzle 16 Melting furnace 17 Stopper rod 18 Melting furnace pouring port 19 Tundish pouring port

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masao Yukimoto 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Inside the Technical Research Institute of Kawasaki Steel (72) Inventor Haruhiko Ishizuka 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki Steel Corporation Chiba Works (72) Inventor Takayuki Yanagimoto 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki Steel Corporation Technical Research Institute

Claims (5)

[Claims] 1. A quenching method in which a molten metal is injected into the surface of a rotating roll with the axial direction of the roll as a width direction from an opening in a nozzle bottom to form a paddle between the opening and the surface of the roll. A nozzle for manufacturing a quenched ribbon, wherein at least one bottom surface of the nozzle wall on both sides of the opening in the width direction is an inclined surface inclined toward the inside of the nozzle. 2. The nozzle according to claim 1, wherein an inclination angle θ of the inclined surface is tan ⁻¹ (5 / L) ° or more according to an observation distance L (mm) to a paddle width end. 3. The nozzle according to claim 1, wherein the inclination angle θ of the inclined surface is 45 ° or less. 4. A method for producing a ribbon using the nozzle according to claim 1, wherein the paddle is passed through a space between the inclined surface and the surface of the roll during production of the ribbon. Observation, and based on the observation result, the nozzle / roll gap, so as to keep the size of the paddle within a predetermined range,
A method for producing a ribbon, comprising controlling at least one of an injection pressure. 5. A roll, a rotating device for rotating the roll, a nozzle for injecting the molten metal onto the roll surface, an intermediate container for storing the molten metal passing through the nozzle, an elevating device for elevating and lowering the intermediate container, A melting furnace for sending the molten metal to the intermediate container,
In a thin ribbon manufacturing apparatus including a valve device for changing a feed amount of the molten metal from the melting furnace to the intermediate container, the nozzle is the nozzle according to any one of claims 1 to 3, and further, paddle observation. And a paddle image by the camera are analyzed to derive the current size of the paddle, and the nozzle / roll gap and injection pressure values g ₀ , such that the deviation between the current size and the predetermined size is _zero , An image analysis device that calculates P ₀ , a lifting control device that drives the lifting device to make the current value of the nozzle / roll gap equal to g ₀ ,
Apparatus for manufacturing a thin strip, characterized in that the current value of the injection pressure and a valve control device for driving the valve device so as to match the P _0.