JP3205887B2 - Continuous casting method of metal plate and mold used for it - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous casting method for metal sheets,
More specifically, the present invention relates to a method for continuously casting a metal ingot (mainly a sheet metal ingot) having a smooth surface and a directionally solidified structure without causing breakout, and It relates to the mold used in carrying out the method. In the present invention, “metal” includes “silicon (Si)”.

[0002]

2. Description of the Related Art Conventionally, as a method for manufacturing a plate made of a metal such as Al, Sn, Bi, Zn, etc., an open top horizontal heating mold type continuous casting method (hereinafter simply referred to as "OSC method") has been adopted. Have been. (The "OSC method" is
Strip Casting Method ”). Thereby, a long metal having a unidirectionally solidified structure is obtained.

Here, the OSC method will be briefly described with reference to FIG. That is, as shown in the figure, the horizontal heating mold (12) to which the molten metal is supplied is heated by the heating element (30) to a temperature equal to or higher than the solidification temperature of the molten metal. The bottom of the mold (12) is deepest near the inlet (32) into which the molten metal flows. Then, it gradually becomes shallower toward the exit (34), and becomes a horizontal plane (36) from the middle.

[0004] Inside the crucible (10) is the crucible (10).
A molten metal (14) that is melted by a heating element (24) that covers the housing is accommodated. Control rods (2
8) By operating the molten metal (14), the mold (1
In the interior of 2), a hot water supply pipe (16) covered with a heating element (26) so that the hot water level (44) is higher than the horizontal plane (36)
And from the inlet (32).

A dummy plate (38) made of graphite is passed through an outlet (3
4) Insert from the tip of this (40) and horizontal heating mold (1
The molten metal (14) flowing from the inlet (32) of 2) is brought into contact with the molten metal (14).

The gas outlet pipe (4) in the cooling device (18)
Since the cooling is performed by blowing argon gas from 2) toward the upper surface of the graphite dummy plate (38), the molten metal (14) in contact with the dummy plate (38) is cooled by the tip ( Coagulation starts in the horizontal direction at 40).

Next, the dummy plate (38) is pulled out rearward (to the right in the drawing) using a pair of upper and lower pinch rolls (22), so that the dummy plate (38) is horizontally pulled from the portion attached to the tip (40) of the dummy plate (38). A metal plate (20) is sequentially formed in the direction, and gradually becomes longer.

The level of the molten metal surface (44) shifts up and down depending on the insertion amount of the control rod (28), and the distance between the molten metal surface (44) and the horizontal surface (36) is reduced by reducing the insertion amount. . Thus, the thickness of the metal plate to be obtained can be appropriately changed by operating the control rod (28).

[0009]

However, the above-mentioned OS
When casting by the C method, in particular, for example, Cu or Si
When thin sheet casting is performed, there is a problem that a breakout occurs. That is, even if the molten metal is supplied to the mold to perform sheet casting, the supplied molten metal gathers in the central portion of the mold and becomes sparse in the peripheral portion due to its large surface tension. If casting was continued in this state, a breakout occurred, and a thin plate-shaped ingot could not be formed.

In order to cast a thin plate-like ingot without causing a breakout, it is necessary to spread a molten metal (molten metal) over the entire surface of the mold so that the molten metal does not gather at the center. In other words, it is necessary to make the molten metal pressure of the metal to be cast equal between the central part and the peripheral part of the mold.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for easily producing a thin plate-like ingot in metal plate casting by the OSC method, and a mold used for the method. There.

[0012]

As a result of intensive studies, the present inventors have found that the shape of the mold is gradually reduced from the central part of the mold toward the inner wall of the mold, thereby achieving the above-mentioned features. The inventors have found that the problems can be solved, and have completed the present invention.

That is, according to the continuous casting method of the present invention, a molten metal is supplied into a mold having a part of the bottom surface being a horizontal plane so that the molten metal surface is higher than the horizontal plane. By directly or indirectly cooling the molten metal, a metal plate is formed on the horizontal surface, and the metal plate is drawn horizontally and continuously from between the left and right side walls toward the rear of the mold. The continuous casting method for producing a long metal plate by the above, wherein the front portion of the horizontal surface has a tapered shape in which the right width and the left width from the center in the width direction become smaller as going forward. An inclined surface which is continuous with the tapered surface and which is inclined downward toward the left and right side walls is provided on both left and right sides of the tapered surface.

Further, in the casting mold of the present invention, the molten metal supplied inside such that a part of the bottom surface is a horizontal surface and the molten metal surface is higher than the horizontal surface may be directly or indirectly above the horizontal surface. The metal plate is formed on the horizontal surface by cooling the metal plate, and the metal plate is horizontally directed rearward,
And a continuous casting mold capable of manufacturing a long metal plate by continuously drawing it from between the left and right side walls, wherein a front portion of the horizontal surface has a right width from a width direction central portion. The left and right sides of the tapered surface are provided with inclined surfaces which are continuous with the tapered surface and which are inclined downward toward the left and right side walls, respectively. It is.

Although there is no particular limitation on how much the tapered surface has a tapered shape, that is, how much the boundary between the tapered surface and the inclined surface is inclined with respect to the drawing direction of the metal plate. It is preferred that it be tilted by 75 °. If the inclination is less than 20 °, it is not preferable because the length of the mold becomes longer, and if it is more than 75 °, the inclined surfaces provided on the left and right sides thereof cannot be made large, and the effect becomes low, which is not preferable. . Note that a more preferable range is 30 to 60 °.

The inclination of the inclined surface depends on the thickness of the metal plate to be manufactured, and cannot be unconditionally determined. However, the angle between the tapered surface and the inclined surface is 135 to 17 degrees.
It is preferable that the angle is 5 ° (the inclination is 5 to 45 °). If it exceeds 175 °, the effect of lowering the melt pressure may be reduced, and if it is less than 135 °, a possibility of breakout between the mold and a horizontal surface may easily occur, which is not preferable. Note that a more preferable range is 150 to 165 °.

The shape of the inclined surface may be any one of a flat surface, a convex surface and a concave surface. However, in order for the ingot to be continuously cast without causing a breakout, the vicinity of the boundary with the tapered surface is smooth. A flat (with radius) or convex surface is preferred.

Further, the boundary line with the tapered surface does not need to be a straight line, and may be partially or entirely curved.

As the material of the mold, any material such as ceramics and metal may be used as long as it does not react with the molten metal, but ceramics is preferable because it is easy to process. In particular, easy to mold, easy to obtain,
Graphite and boron nitride, silicon nitride,
It is desirable to use ceramics such as aluminum nitride, aluminum oxide, or a mixed sintered body thereof.

By using the template of the present invention, OSC
The reason why the thin plate casting by the method becomes easy is as follows.

That is, when the molten metal is spread on the mold, as described above, due to its large surface tension,
The melt pressure at the center of the mold and that at the periphery are greatly different, and the center of the mold is larger. Therefore, if the molten metal pressure is reduced to produce a thin plate ingot, as described above, the molten metal becomes difficult to flow around the mold, that is, the molten metal gathers in the central portion, and as a result, the thin plate ingot becomes In addition, continuous casting becomes difficult due to failure or breakout.

As a mold for performing continuous casting, the tapered surface is provided at a front portion of the horizontal plane, and an inclined surface which is continuous with the tapered surface and is inclined downward toward left and right side walls is provided. By using the mold, the molten metal pressure in the central part of the mold and the molten metal pressure in the peripheral part thereof become uniform, so that there is no possibility that the supplied molten metal is concentrated in the central part of the mold. It will be easier.

In the present invention, not only Cu and Si, but also noble metals such as Au, Ag, Pt, Rh, Ir, Ni,
For a transition metal such as Fe, Cr, Mn, Ti, and V, a thin plate-like ingot can be produced.

[0024]

According to the casting method and the mold of the present invention, even for a metal such as Cu or Si, which is difficult to obtain a thin ingot,
A thin plate-shaped ingot can be obtained easily and without breakout.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings, but the present invention is not limited thereto.

[Embodiment] FIGS. 1 to 3 are views showing a casting apparatus (top-open horizontal heating mold type continuous casting apparatus) for carrying out the casting method of the present invention.

The casting apparatus is roughly divided into a crucible (10) for melting Cu, a horizontal heating mold (12) for casting a Cu plate, and a crucible connecting the crucible (10) and the horizontal heating mold (12). From (10), the molten Cu (1
4) Hot water supply pipe (16) for supplying, horizontal heating mold (1
2) Cooling device (18) provided above and cast C
It is composed of a pair of upper and lower pinch rolls (22) (22) for pulling out the u-plate (20) horizontally (rightward in the drawing) horizontally and continuously.

The crucible (10) and the hot water supply pipe (16) are heated above the melting temperature of Cu by heating elements (24) and (26) provided on the outer periphery thereof, respectively.

Inside the crucible (10), a control rod (28) having an outer dimension slightly smaller than the inner dimension of the crucible (10) is inserted. The molten metal surface (44) of the molten Cu (14) is kept constant.

The horizontal heating mold (12) is made of boron nitride, with both side walls (12a) (12a) constituting the left and right sides thereof, a front wall (12b) constituting the front part, and a bottom plate (12c) constituting the bottom part. And a mixed sintered body of silicon nitride (manufactured by Kawasaki Furnace Materials Co., Ltd.). The temperature of the mold (12) is
By controlling the amount of current supplied to the heating element (30) provided under c), the temperature is adjusted to be equal to or higher than the solidification temperature of the molten Cu.

The discharge side of the Cu plate on the bottom surface of the horizontal heating mold (12), that is, the pinch roller (22) side is a horizontal plane (36) as shown in FIGS.

The front part of the horizontal plane (36) has a tapered shape in which the width is gradually reduced toward the front,
The tip (36b) has a tapered surface (36a) passing through the center in the width direction of the mold (12).

On both left and right sides of the tapered surface (36a), the mold (12)
There are provided inclined surfaces (48) (48) inclined downward toward the left and right side walls (12a) and (12a), and also downward toward the front wall (12b). It should be noted that the inclined surface (48) can obtain a superior effect as long as it is inclined downward toward the left and right side walls (12a) and (12a) of the mold (12), but obtains a more excellent effect. For this purpose, as in the present embodiment, it is preferable that the inclination is also downward toward the front wall (12b).

Reference numeral (13) denotes a slope formed in front of the inclined surfaces (48) and (48). This slope (13)
It is continuous with the slopes (48) and (48) via the ridgeline (15), and is inclined downward toward the front wall (12b) at a slope greater than the slope in the front-rear direction on the slope (48). I have.

In the present embodiment, the boundary line (46) between the tapered surface (36a) and the inclined surface (48) extends at an angle of 40 ° with respect to the drawing direction of the Cu plate (that is, R in FIG. 40 °). The angle between the tapered surface (36a) and the inclined surface (48) is 160 °.

In order to manufacture a Cu plate, a graphite heating plate (12) is first maintained by a heating element (30) at a temperature higher than the solidification temperature of Cu, as shown in FIG. (38) is the horizontal plane (3
6) Insert the dummy plate (38) through the outlet (34) so as to be placed on top.

Thereafter, by operating the control rod (28), the molten Cu (14) is supplied from the crucible (10) to the hot water supply pipe (16).
And feed into the horizontal heating mold (12) through the inlet (32). The molten metal surface (44) of the supplied molten Cu (14)
It is located above the horizontal plane (36).

The molten Cu (14) flowing from the inlet (32) of the horizontal heating mold (12) is converted into a graphite dummy plate (38).
Contacts the insertion end (40) of the Argon gas for cooling is blown from the gas blowing pipe (42) of the cooling device (18) to the molten Cu supply side on the upper surface of the graphite dummy plate (38) avoiding the inner wall surface of the horizontal heating mold (12). Thus, the molten Cu (14) in contact with the insertion end (40) of the dummy plate (38) starts solidifying (crystallizing) in the horizontal direction from the dummy plate (38). Symbol (50) in FIG.
Indicates a solidification interface.

Next, the dummy plate (38) made of graphite is pulled backward by using the pinch roll (22), and simultaneously, the Cu plate (20) solidified at the tip (40) of the dummy plate (38) is pulled out. By further drawing with a pinch roll (22) and further blowing of a cooling gas, a long Cu plate (20) is continuously obtained (see FIG. 3).

At this time, the depth of the molten Cu (14) from the molten metal surface (44) to the horizontal surface (36) determines the thickness of the manufactured Cu plate (20). Therefore, the thickness of the Cu plate (20) can be changed by changing the insertion amount of the control rod (28) into the crucible (10) and adjusting the molten metal surface (44). The minimum thickness (the thickness at the center in the width direction) of the Cu plate (20) stably obtained using the mold (12) was 1 mm.

The crucible (10) for melting Cu and the horizontal heating mold (12) are connected by a hot water supply pipe (16). However, these crucibles (10) and the horizontal heating mold (12) are integrated. It may be formed in a typical manner.

As shown in FIG. 4, the slope (13)
Through a ridge line (17) extending in the width direction and a tapered surface (36a).
Can be provided continuously.

[Comparative Example] The same as the above-mentioned embodiment except that a mold having no inclined surfaces (48) and (48) and having a horizontal plane (36) extending to both left and right side walls (12a) and (12a) was used. Similarly, a Cu plate was cast by the OSC method. In order to reduce the thickness of the plate, if the degree of insertion of the control rod is reduced, Cu
The molten metal gathered in the center of the mold, making it impossible to cast a thin plate. The minimum thickness (the thickness at the center in the width direction) of the Cu plate obtained stably was 6 mm.

[Brief description of the drawings]

FIG. 1 is a partially omitted cross-sectional perspective view showing one example of an open-top horizontal heating mold type continuous casting apparatus used in carrying out a casting method of the present invention.

FIG. 2 is a plan view of a main part showing a shape of a horizontal heating mold in FIG.

FIG. 3 is a perspective view showing a state where a metal plate is formed in FIG. 1;

FIG. 4 is a main part plan view showing another shape of the horizontal heating mold.

FIG. 5 is a perspective view showing a state of a conventional continuous casting.

[Explanation of symbols]

 10 Crucible 12 Horizontal heating mold 13 Slope 14 Melted Cu 15, 17 Ridge line 16 Hot water supply pipe 18 Cooling device 20 Cu plate 22 Pinch roll 24, 26 , 30 heating element 28 control rod 32 inlet (of horizontal heating mold) 34 outlet (of horizontal heating mold) 36 ... horizontal surface (of horizontal heating mold) 38 dummy plate 40 Tip (dummy plate) 42 Gas blow-out tube 44 Hot surface (of molten Cu) 46 Boundary line (with tapered surface) 48 Slope 50 Solidification interface

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-60-121047 (JP, A) JP-A-63-278640 (JP, A) JP-A-3-243247 (JP, A) JP-A 63-278 313634 (JP, A) JP-A-7-41393 (JP, A) JP-A-6-210406 (JP, A) JP-A-60-121047 (JP, A) JP-A-59-229262 (JP, A) JP-A 4-125046 (JP, U) JP-A 61-63345 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B22D 11/04 301 B22D 11/04 311 B22D 11 / 00 B22D 11/04 114

Claims (6)

(57) [Claims] 1. A mold in which a part of the bottom surface is a horizontal plane,
The molten metal is supplied such that the molten metal surface is higher than the horizontal surface, and the molten metal is directly or indirectly cooled above the horizontal surface to form a metal plate on the horizontal surface. A continuous casting method for manufacturing a long metal plate by horizontally pulling a metal plate toward the rear of the mold and continuously and between the left and right side walls, wherein a front portion of the horizontal plane has a width of The right side width and the left side width from the center of the direction have a tapered shape that becomes smaller as going forward, and the left and right sides of this tapered surface are respectively continuous with the tapered surface and downward toward the left and right side walls. A continuous casting method for a metal plate, wherein an inclined surface is provided. 2. The method according to claim 1, wherein the molten metal is molten Cu or molten Si.
The continuous casting method according to claim 1, wherein 3. The method according to claim 1, wherein a boundary between the tapered surface and the inclined surface is inclined at 20 to 75 ° with respect to a drawing direction of the metal plate, and an angle between the tapered surface and the inclined surface is 135 to 175 °. The continuous casting method according to claim 1 or 2, wherein: 4. A method according to claim 1, wherein a part of the bottom surface is a horizontal plane, and the molten metal supplied therein is cooled directly or indirectly above the horizontal plane so that the molten metal level is above the horizontal plane. A continuous casting in which a metal plate is formed on the horizontal plane, and the metal plate is horizontally drawn rearward and continuously drawn out from between the left and right side walls so that a long metal plate can be manufactured. The front part of the horizontal plane has a tapered shape in which the right width dimension and the left width dimension from the center in the width direction become smaller toward the front, and the left and right sides of the tapered surface are respectively provided. A mold, characterized by being provided with an inclined surface that is continuous with the tapered surface and that is inclined downward toward the left and right side walls. 5. The method according to claim 1, wherein the molten metal is molten Cu or molten Si.
The mold according to claim 4, wherein 6. A method according to claim 1, wherein a boundary between the tapered surface and the inclined surface is inclined at 20 to 75 ° with respect to a drawing direction of the metal plate, and an angle between the tapered surface and the inclined surface is 135 to 175 °. The template according to claim 4 or 5, wherein