JPWO2006013654A1 - Molten metal direct rolling equipment - Google Patents

Abstract

We propose a molten metal direct rolling device that can directly roll the molten metal and stably form a metal plate with excellent quality.
A pair of upper and lower rolling rolls 21 and 22 arranged so as to incline a plane f passing through both rotation axes P ₁ and P ₂ from the vertical direction to within about 45 degrees toward the discharge side, and the inclination direction of the rolling rolls. The horizontal supply nozzle 12 for supplying the molten metal X between the upper and lower rolling rolls 21 and 22, which are arranged in a non-contact manner with the molten metal X, and the horizontal supply nozzle 12 for maintaining the molten metal X at a substantially constant level. The apparatus 1 is provided with a molten metal supply means for supplying, and the contact circumferential lengths L ₁ and L ₂ that come into contact with the upper and lower rolling rolls are made substantially equal to each other. This apparatus 1 is capable of stably producing a metal plate that does not cause surface defects and has a morphological symmetry in the plate thickness direction, and is highly practical as a manufacturing apparatus.

Description

  The present invention relates to a molten metal direct rolling apparatus for forming a metal plate by directly rolling a molten metal.

  As a method for directly forming a metal plate from a molten metal, a strip continuous casting method and a molten metal direct rolling method are known. Here, the molten metal direct rolling method is a method of forming a desired metal plate by solidifying and rolling the molten metal injected between a pair of rolling rolls, and heat that cannot be obtained by the strip continuous casting method. It is possible to form a metal plate having an expanded structure.

As such a molten metal direct rolling method, the inventors of the present invention, for example, as in Non-Patent Document 1 (see FIG. 8), provide a pair of rolling rolls 61 and 62 with a surface f passing through the rotation axis of both of them. It is arranged so as to be inclined about 45 degrees toward the discharge side with respect to the vertical direction, and the injection head is reduced in the region defined by the rolling rolls 61 and 62 and the side dams provided on both sides thereof. An apparatus 60 for injecting a molten metal X (a molten aluminum alloy) to form a metal plate Y′ (aluminum alloy plate) is proposed. In this molten metal direct rolling apparatus 60, the position where the solidified metal (solidified shell) solidified by contacting the molten metal with the rolling rolls 61, 62 is sent by the rolling rolls 61, 62 and meets is the distance between the rolling rolls 61, 62. By setting it considerably on the supply side compared to the narrowest rolling end of the narrowest rolling end, a large clamping force (rolling load) that cannot be generated by the above strip continuous casting method is generated on the metal immediately after solidification, and a high reduction ratio is achieved. It can be rolled. Here, the reduction rate is the reduction rate of the distance between the rolling rolls 61 and 62 from the position where the solidified metal meets and the solidification is completed to the narrowest rolling end (details will be described later). That is, the molten metal direct rolling apparatus 60 solidifies the molten metal X and performs rolling at a large reduction ratio corresponding to normal hot rolling, so that the molten metal X corresponds to a hot rolled thin plate in one step. It is an apparatus capable of forming a metal plate Y′.
Journal of Japan Society for Plasticity Processing Vol. 36, No. 418, p1281 to p1287

  In the above-described conventional molten metal direct rolling apparatus, the molten metal is dropped from the gutter-shaped tundish onto the lower rolling roll, and then flows into the area defined by the upper and lower rolling rolls and the side dam. It is designed to form a pool of hot water. However, in this conventional molten metal direct rolling apparatus, since a small pool of the molten metal is formed on the rolling roll, it is difficult to control the level of the molten metal level of the molten metal pool to be constant and the level of the molten metal easily fluctuates. Therefore, as described above, the position where the solidified metal meets and completes solidification is likely to change, and the rolling load and the rolling reduction change accordingly. Therefore, the thickness of the metal plate after forming, its structure There is a problem that it is difficult to stabilize the morphology and mechanical properties such as strength and ductility in the longitudinal direction of the metal plate.

  Further, in the molten metal direct rolling apparatus having the conventional configuration, as described above, the molten metal is supplied by being dropped into the pool on the rolling roll, so that the molten metal surface is likely to be wavy. For this reason, there is a problem that the metal melt is disturbed at the first contact with the rolling roll (so-called contact start end), and surface defects are easily generated on the metal plate after forming.

  Further, since the molten metal is supplied between the rolling rolls using the gutter-shaped tundish as described above, it is difficult to supply the molten metal evenly in the roll width direction, and therefore the temperature distribution of the molten metal in the pool Tends to be non-uniform in the roll width direction. As a result, the reduction ratio is also non-uniform in the roll width direction, and accordingly, the plate thickness, structure, mechanical properties, etc. of the metal plate tend to be non-uniform in the width direction. There is also a problem that shape defects such as poor flatness are likely to occur.

  Further, as a result of detailed research conducted by the present inventors on the aluminum alloy sheet formed by the molten metal direct rolling apparatus having the conventional configuration, it was found that the microstructure was formed asymmetrically in the sheet thickness direction. In addition, as a result of chemical composition analysis of the same aluminum alloy plate, it was found that the solute has a reverse segregation that is concentrated as it is closer to the plate surface.Furthermore, the distribution of this solute also becomes asymmetric in the plate thickness direction. Was there. In the metal plate formed in such an asymmetric structure, the mechanical properties are unevenly expressed in the plate thickness direction, which adversely affects the mechanical properties of the product.

  Furthermore, since the metal immediately after solidification is rolled at a high reduction ratio in the direct molten metal rolling, slip and seizure are likely to occur between the roll and the solidified metal. In a conventional molten metal direct rolling apparatus, in order to prevent this, soot is generated on the roll surface by incomplete combustion of propane gas as a lubricant release agent, but this method is difficult to control the soot adhesion amount.

  From the above, even if the above-mentioned conventional molten metal direct rolling apparatus is applied as a manufacturing apparatus, it is difficult to form a metal plate while maintaining desired quality, and stable production is not possible. Therefore, this molten metal direct rolling device cannot be put to practical use as a device for manufacturing a metal plate. The present invention solves such a problem and proposes a practical molten metal direct rolling apparatus capable of stably forming a metal plate of excellent quality.

  The present invention provides a pair of upper and lower water-cooled rolling rolls in which both rotary axes are horizontal and parallel to each other, and a plane passing through both rotary axes is vertical or inclined to the discharge side within about 45 degrees. And a horizontal supply path for supplying the molten metal between the upper and lower rolling rolls is formed, a horizontal supply nozzle arranged in a non-contact state with a small gap with the roll surface of the lower rolling roll, and maintained at a predetermined temperature. The molten metal supplied from the horizontal supply nozzle is provided with a molten metal supply means for sequentially supplying the molten metal to maintain a substantially constant molten metal surface height in the supply path of the horizontal supply nozzle. From the upper and lower contact start ends in contact with the upper rolling roll or the lower rolling roll to the narrowest rolling end with the narrowest distance between the upper and lower rolling rolls, the upper and lower contact circumferential lengths are set to be substantially equal. It is a characteristic molten metal direct rolling device. This molten metal direct rolling apparatus forms a hot-rolled sheet (metal plate) from the molten metal in one step by performing rapid solidification of the molten metal and rolling of the solidified metal corresponding to ordinary hot rolling. Is something that can be done.

  In such a configuration, unlike the conventional configuration described above, without forming a pool of molten metal on the rolling roll, the metal melt that is gently fed in a calm state by the horizontal supply nozzle and the melt supply means, It is arranged so that it is sequentially supplied between the upper and lower rolling rolls. As a result, the molten metal can be stably supplied at a substantially constant molten metal surface height, so that the solidified metal (solidified shell) solidified by contacting the upper and lower rolling rolls and the upper and lower rolling rolls respectively meet each other at a position where the solidification is completed. Since it is always fixed and a substantially constant rolling reduction and rolling load can be applied, a metal plate having a desired plate thickness and structure morphology can be stably formed. Further, since the molten metal can be supplied gently while always maintaining a calm state, the surface of the molten metal does not swell and surface defects due to this do not occur in the metal plate.

  Furthermore, since this horizontal supply nozzle can be arranged with its tip at any position on the supply side from the apex part of the lower rolling roll, the contact circumferential length at which the molten metal comes into contact with the lower rolling roll is It can be set arbitrarily. On the other hand, the contact circumferential length with which the molten metal comes into contact with the upper rolling roll can be arbitrarily adjusted by the height of the molten metal surface. Therefore, since it is possible to arbitrarily and equalize the contact circumferential length of the upper and lower rolling rolls, unlike the above-described conventional configuration, the structure morphology and mechanical properties are not formed asymmetrically in the plate thickness direction, It may be possible to form a metal plate whose structure morphology and mechanical properties are symmetrical in the plate thickness direction.

  Further, since this horizontal supply nozzle is mounted so as to be arranged in a non-contact state with a small gap provided between the horizontal supply nozzle and the lower rolling roll, the horizontal supply nozzle is not contact-cooled by the lower rolling roll. Therefore, the temperature drop of the molten metal in the supply passage of the horizontal supply nozzle can be minimized.

  Further, in the molten metal direct rolling apparatus of the present invention, the molten metal supply means can uniformly supply the molten metal held at the predetermined temperature in the roll width direction by the horizontal supply nozzle, so that the first contact with the rolling roll is made. Since the temperature of the molten metal at the start end can be uniformly controlled in the roll width direction, the rolling reduction is also uniform in the roll width direction, and accordingly, the plate thickness, structure, mechanical properties, etc. of the metal plate can be uniform in the roll width direction.

Next, the arrangement of the upper and lower rolling rolls will be described in detail (see FIG. 4).
In the molten metal direct rolling method, after the molten metal X supplied between the upper and lower rolling rolls 21 and 22 is appropriately solidified, rolling is started according to the rotation of the rolling rolls 21 and 22. At this time, if the friction coefficient μ between the rolling rolls 21 and 22 and the solidified metal (solidified shell) x is not sufficiently large, the rolling rolls 21 and 22 slip with the solidified metal x and the rolling process cannot be started. If the molten metal contact angles φ forming the contact circumferential lengths L ₁ and L ₂ between the rolling rolls 21 and 22 and the solidified metal x are equal in the upper and lower rolling rolls, the condition that no slip occurs is that the known biting condition is
φ≦2 tan ⁻¹ μ (1)
Is expressed as
Further, since the tip 13 of the horizontal supply nozzle 12 is arranged on the supply side from the top portion of the lower rolling roll 22, it passes through the rotation axes P ₁ and P ₂ of the upper and lower rolling rolls 21 and 22 in the vertical direction. The inclination angle θ of the surface f is
φ≧θ (2)
Is expressed as
From these equations (1) and (2),
θ≦2 tan ⁻¹ μ (3)
Therefore, the upper limit of the inclination angle θ is obtained. Here, since the friction coefficient μ is generally about 0.4 when performing hot non-lubricating rolling of an aluminum alloy, the upper limit of the inclination angle θ is about 45 degrees.

On the other hand, the lower limit value of the inclination angle θ is determined based on the condition that the molten metal X does not enter the gap between the tip 13 of the horizontal supply nozzle 12 and the lower rolling roll 22 and the molten metal does not leak. This condition is that the molten metal depth h ₀ at the tip 13 of the horizontal supply nozzle 12 does not exceed a predetermined critical value determined by the gap and the surface tension of the molten metal. Here, the molten metal depth h ₀ is the distance between the tip 13 of the horizontal supply nozzle 12 and the contact start end B ₁ where the molten metal X contacts the upper rolling roll 21 (the depth of the molten metal X into the upper and lower rolls 21 and 22). H) For h _S ,
h ₀ =h _S cos θ (4)
Have a relationship. Accordingly, the larger the inclination angle θ is, the smaller the molten metal depth h ₀ is. Therefore, if the distance h _S is sufficiently smaller than the critical value, the inclined angle θ may be 0 degree, but the molten metal depth h ₀ Under the condition that is close to the critical value or exceeds the critical value, the larger the tilt angle θ is, the safer it is.

Therefore, due to the above-mentioned upper limit value and lower limit value of the inclination angle θ, the arrangement form of the upper and lower rolling rolls 21 and 22 is such that the plane f passing through the rotation axis P ₁ or P ₂ of each rolling roll 21 or 22 is vertical. Alternatively, it will be inclined to the discharge side within about 45 degrees.

  Further, in the molten metal direct rolling apparatus of the present invention, the pair of upper and lower rolling rolls have a water-cooling type cooling function so that the molten metal in contact can be appropriately solidified. This water-cooling type cooling function has an internal water-cooling type configuration in which a circulation path for circulating cooling water is provided inside the roll, or an external water-cooling type configuration in which the roll processing surface is directly cooled by cooling water from outside the roll. Can be used. As a result, the rolling roll exerts an excellent heat removal ability and can rapidly solidify the molten metal. In addition, since the molten metal direct rolling apparatus of the present invention performs rolling with a large reduction corresponding to normal hot rolling, a large rolling load acts on the rolling rolls. Therefore, the rolling roll is required to have high cooling capacity and sufficient strength. Therefore, as the rolling roll, an internal water cooling type sleeve type water cooling roll, which is optimally designed by using an alloy tool steel having both strength and thermal conductivity, can be suitably used.

  Thus, in the molten metal direct rolling apparatus of the present invention, it is possible to stably form a metal plate of excellent quality which does not cause surface defects and has a morphological morphology and mechanical properties symmetrical in the plate thickness direction. Therefore, it can be sufficiently used as a practical manufacturing apparatus.

In the above-described molten metal direct rolling apparatus, the molten metal supplied by the horizontal supply nozzle and solidified by contacting the pair of upper and lower water-cooled rolling rolls is rolled by the rolling rolls at a reduction ratio of about 40% or more ((1 A configuration is proposed in which the rolling process can be performed with the minimum distance t between rolls/total thickness solidification starting thickness t ₀ )×100). In the molten metal direct rolling device, the metal solidified by the upper and lower rolling rolls is rolled by the same roll at a reduction rate of about 40% or more, so that the dendrites generated during solidification are transformed into a structure elongated in the longitudinal direction. Along with the modification, internal defects such as micro voids and cracks that can be generated at the time of solidification or immediately after the start of rolling and surface defects such as ripple marks can be repaired by crimping or smoothing to form a metal plate of excellent quality. .. Here, the rolling reduction is defined by (1-narrowest distance between rolls t 1 /total thickness solidification start thickness t ₀ )×100%. Further, the minimum distance t between the rolls is the distance between the rolls at the narrowest rolling edges A ₁ and A ₂ where the distance between the upper and lower rolling rolls 21 and 22 is the narrowest in FIG. t ₀ is the thickness at which the molten metal X completes solidification and starts rolling.

  Further, in the above-mentioned molten metal direct rolling apparatus, a concave circumferential groove formed around the surface of the lower rolling roll, and a fitting convex circumferential portion formed around the surface of the upper rolling roll that can be fitted into the concave circumferential groove. A configuration is proposed in which the molten metal supplied between the upper and lower rolling rolls by the horizontal supply nozzle is rolled together with solidification by the groove bottom surface of the concave circumferential groove and the convex top surface of the fitting convex circumferential portion. It In the molten metal direct rolling apparatus of the present invention, as described above, since the rolling process is applied to the metal immediately after solidification at a large reduction ratio corresponding to ordinary hot rolling, the solidified metal is rolled by this high reduction ratio. Attempts to widen and deform between. In particular, it becomes remarkable when rolling with a reduction ratio of more than about 40%. In such a configuration, this widening deformation can be suppressed by the side wall of the concave circumferential groove in which the fitting concave circumferential portion is fitted, and therefore, the metal having a constant width corresponding to the groove width of the concave circumferential groove. The plate can be continuously formed. Here, if a slight gap is provided between the side wall of the concave circumferential groove 25 and the side surface of the fitting convex circumferential portion, the width can be appropriately suppressed by forming a burr in the gap. It is possible because it is possible. Incidentally, in this configuration, the groove bottom surface of the concave circumferential groove of the lower rolling roll and the convex top surface of the fitting convex circumferential portion of the upper rolling roll solidify the molten metal supplied by the horizontal supply nozzle, and It is a roll processing surface to be rolled.

  Here, there is proposed a configuration in which concave circumferential grooves formed on the surface of the lower rolling roll are provided with groove side walls that are inclined outward by about 3 degrees or more and about 10 degrees or less on both sides. In the molten metal direct rolling equipment, in order to discharge the rolled metal sheet straightly without wrapping around the rolling roll, the groove side wall of the concave circumferential groove formed on the surface of the lower rolling roll should be removed. It must be provided with an appropriate inclination angle (so-called draft angle). This is a well-known technique for a processing apparatus that hot-rolls a metal square bar between a concave groove and a fitting convex portion. However, in the molten metal direct rolling apparatus for forming a metal plate, there has been no knowledge of this draft until now. The present inventors, as a result of performing a detailed study of the influence of the draft using aluminum alloy, the groove side wall of the concave circumferential groove of the lower rolling roll, and formed on both sides of the fitting convex circumferential portion of the upper rolling roll It was also clarified that when a graphite grease-based lubricant release agent is applied to the convex peripheral wall, a draft angle of about 3 degrees or more and about 10 degrees or less is appropriate. Here, when the groove side wall is formed to have a draft of about 3 degrees, a high surface pressure is generated between the groove side wall and the metal plate, so that the metal plate is likely to be partly seized and the metal plate tends to be easily wound around the lower rolling roll. is there. On the other hand, in the case of forming the draft angle of about 10 degrees, the gap between the groove side wall and the convex peripheral wall becomes large, so that the surface pressure between the groove side wall and the metal plate is reduced, and the metal plate easily comes off from the lower rolling roll. However, since thick and large burrs are formed along the upper rolling roll during the rolling process, on the contrary, it tends to be easily wound around the upper rolling roll.

  Further, a lubricant release agent that applies a lubricant release agent to the groove side walls formed on both sides of the concave circumferential groove of the lower rolling roll and the convex circumferential walls formed on both sides of the fitting convex circumferential portion of the upper rolling roll. A configuration with a coating device is proposed. With such a configuration, when the molten metal direct rolling device is forming a metal plate, a proper amount of the lubricant release agent is applied to the groove side wall and the convex peripheral wall by the lubricant release agent applying device. It is something that can be maintained. Thereby, even if the metal plate is continuously formed, it is possible to prevent the metal plate from being seized on the groove side wall and the convex peripheral wall by the lubricant release agent. Thus, the molten metal direct rolling apparatus of this configuration can be more practical. As the lubricant release agent applying device, a device which is controlled to always apply a predetermined amount of the lubricant release agent or a device which is controlled to apply the lubricant release agent regularly at predetermined intervals. Can be

  On the other hand, in the above-described molten metal direct rolling apparatus, a pair of upper and lower water-cooled rolling rolls solidify the molten metal supplied from the horizontal supply nozzle and roll-process the rolled surface to roll Ra about 0.5 μm or more to about 5 μm. A configuration is proposed in which a large number of minute recesses of 0.0 μm or less are formed. Here, Ra of about 0.5 μm or more and about 5.0 μm or less means that the average depth of the depressions is in the range of about 0.5 μm or more and 5.0 μm or less. By providing such a roll processed surface, it is possible to prevent the molten metal supplied from the horizontal supply nozzle from being seized. Here, in order to prevent the seizure of the molten metal, it is common to apply a predetermined release agent to the roll surface with which the molten metal contacts in the strip continuous casting method, but in the molten metal direct rolling method immediately after solidification Since the metal of No. 1 is rolled at a large reduction rate, the release agent is easily peeled off, and the molten metal will be burned at the peeled portion, so the release agent application is not suitable for continuous molding of metal plates. .. On the other hand, the present configuration is a molten metal direct rolling apparatus in which a large clamping force acts, and it is possible to prevent the molten metal from being seized on the roll processed surface without applying a release agent. Furthermore, since the roll-processed surface has a sufficiently high friction coefficient, the metal immediately after solidification can be processed by rolling without slip even at a large reduction rate. Therefore, the present configuration can further enhance the molding stability of the metal plate and exhibit high practicality when the desired metal plate is continuously formed by the molten metal direct rolling device of the present invention. .. Here, when the dent on the roll-processed surface is smaller than Ra 0.5 μm, the coefficient of friction is small, and slippage is likely to occur. On the other hand, when Ra is larger than 5.0 μm, the function of preventing the seizure of the molten metal is lowered, and the surface of the formed metal plate is roughened and the luster is dull.

  Further, in the molten metal direct rolling apparatus described above, a pair of upper and lower water-cooled rolling rolls, the roll processing surface for solidifying and rolling the molten metal supplied from the horizontal supply nozzle, a substantially uniform spherical shot grain. A structure formed by shot peening is proposed. The roll-processed surface having such a structure has a large number of minute dents each having a substantially uniform curved surface. Further, when viewed microscopically, the dents may be smoothly continuous. This roll-processed surface becomes more excellent in the function and effect of preventing the seizure of the molten metal described above. Moreover, since the shot peening process is performed by spraying shot particles at a relatively high speed, the surface temperature of the processed surface rises during this process. By increasing the surface temperature at the time of this processing to the A3 transformation point or higher, the quenching action can be performed, so that the durability of the roll processed surface can be further improved. As a result, in the case of continuously forming a metal plate, the working effect of the roll-worked surface is maintained for a long period of time, which further enhances the practicability of the molten metal direct rolling device of the present invention.

  Further, the above-mentioned molten metal supply means is connected to a horizontal supply nozzle, and a tundish that holds the molten metal at the same level as the horizontal supply path of the horizontal supply nozzle and a tundish that communicates with the tundish to melt the molten metal. A holding furnace for holding at a predetermined temperature and a communication path between the holding furnace and the tundish are provided, and the molten metal in the holding furnace flows in so as to keep the level of the molten metal in the tundish almost constant. An arrangement is proposed which comprises a control valve for controlling. Here, the tundish is an intermediate holding furnace in which the molten metal is once transferred from the holding furnace and is supplied to the horizontal supply nozzle. In such a configuration, the molten metal is allowed to flow from the holding furnace to the horizontal supply nozzle through the tundish so that the molten metal can be gently supplied along the horizontal direction between the upper and lower rolling rolls, and the control is performed. The valve controls the inflow amount of the molten metal from the holding furnace to the tundish so that the level of the molten metal between the supply passage of the horizontal supply nozzle and the tundish is kept substantially constant. As a result, a certain amount of molten metal is sequentially supplied between the rolling rolls while maintaining the predetermined temperature, so that the above-described metal plate without internal defects or surface defects is stably formed. The effect of the present invention can be properly and easily exhibited.

  Further, a configuration is proposed in which the horizontal supply nozzle described above is provided with side dams on both sides of the horizontal supply path for supplying the molten metal to prevent the molten metal flowing through the horizontal supply path from protruding in both directions. It In such a structure, the side dam prevents the molten metal flowing through the horizontal supply passage of the horizontal supply nozzle from protruding in both directions, and also prevents the molten metal supplied between the upper and lower rolling rolls from protruding in both directions. I am trying. Therefore, almost all of the molten metal supplied from the horizontal supply nozzle is molded as a metal plate, so that the material production efficiency can be made extremely high.

  The present invention, as described above, has a pair of upper and lower sides which are arranged such that both rotation axes are horizontal and parallel to each other, and the plane passing through both rotation axes is vertical or inclined to the discharge side within about 45 degrees. A water-cooled rolling roll, a horizontal supply path for supplying a molten metal between the upper and lower rolling rolls is formed, a horizontal supply nozzle arranged in a non-contact manner with a small gap with the roll surface of the lower rolling roll, The horizontal supply nozzle is provided with a molten metal supply means for sequentially supplying the molten metal held at a predetermined temperature so as to maintain a substantially constant molten metal surface height in the supply path of the horizontal supply nozzle. The upper and lower contact circumferential lengths of the molten metal from the upper and lower contact start ends that come into contact with the upper rolling roll or the lower rolling roll to the narrowest rolling end with the smallest distance between the upper and lower rolling rolls are almost equal. This is a molten metal direct rolling device. According to this molten metal direct rolling device, it is possible to stably form a metal plate of excellent quality having no surface defect and having a morphological structure and mechanical properties symmetrical in the plate thickness direction. Thus, the molten metal direct rolling apparatus of the present invention can be sufficiently used as a practical manufacturing apparatus.

In the above-mentioned molten metal direct rolling apparatus, the molten metal supplied by the horizontal supply nozzle and solidified by contact with the pair of upper and lower water-cooled rolling rolls has a rolling reduction of about 40% or more ((( In the configuration in which the rolling process can be performed with the 1-roll minimum distance t/total thickness solidification starting edge thickness t ₀ )×100), the rolling process can be performed by applying a large clamping pressure corresponding to normal hot rolling. As a molten metal direct rolling apparatus, the above-described effects of the present invention can be properly and reliably exhibited, and the apparatus has high practicability.

  Further, a concave circumferential groove formed around the surface of the lower rolling roll, and a fitting convex circumferential portion formed around the surface of the upper rolling roll that can be fitted into the concave circumferential groove, are supplied into the concave circumferential groove. In a configuration in which the molten metal is rolled together with solidification by the groove bottom surface of the concave circumferential groove and the convex top surface of the fitting convex circumferential portion, the molten metal has a constant width corresponding to the groove width of the concave circumferential groove. The metal plate can be continuously molded, and the molding stability of the metal plate can be further improved.

  Here, in the structure in which the concave circumferential groove formed on the surface of the lower rolling roll is provided with the groove side walls inclined outward at about 3 degrees or more and about 10 degrees or less on both sides, it is rolled. The metal plate can be discharged straight without being wound around a rolling roll, and the metal plate can be stably and continuously formed.

  Further, a lubricant release agent that applies a lubricant release agent to the groove side walls formed on both sides of the concave circumferential groove of the lower rolling roll and the convex circumferential walls formed on both sides of the fitting convex circumferential portion of the upper rolling roll. In the configuration including the coating device, the groove side wall and the convex peripheral wall can be maintained in a state in which the lubricant release agent is applied in an appropriate amount, and the molten metal is prevented from sticking to the groove side wall or the convex peripheral portion. it can. Thus, the molten metal direct rolling apparatus can be more practical.

  On the other hand, in the above-described molten metal direct rolling apparatus, a pair of upper and lower water-cooled rolling rolls solidify the molten metal supplied from the horizontal supply nozzle and roll-process the rolled surface to roll Ra about 0.5 μm or more to about 5 μm. With a structure in which a large number of minute recesses of 0.0 μm or less are formed, seizure of the molten metal can be prevented without applying a lubricant to the roll-processed surface, and slippage does not occur even at a large reduction rate, and immediately after solidification. The metal can be rolled. Thus, the molten metal direct rolling apparatus of the present invention can further enhance the molding stability of the metal plate and exhibit high practicality when the desired metal plate is continuously molded.

  Further, in the molten metal direct rolling apparatus described above, a pair of upper and lower water-cooled rolling rolls, the roll processing surface for solidifying and rolling the molten metal supplied from the horizontal supply nozzle, a substantially uniform spherical shot grain. In the constitution which is formed by the shot peening process according to, the roll processed surface is more excellent in the effect of preventing the seizure of the molten metal described above. Further, since it becomes possible to further improve the durability of the roll-processed surface, the above-mentioned effects of the roll-processed surface can be maintained for a long period of time, further improving the practicality of the molten metal direct rolling device of the present invention. ..

  Further, the above-mentioned molten metal supply means is connected to a horizontal supply nozzle, and a tundish that holds the molten metal at the same level as the horizontal supply path of the horizontal supply nozzle and a tundish that communicates with the tundish to melt the molten metal. A holding furnace for holding at a predetermined temperature and a communication passage between the holding furnace and the tundish, which controls the inflow of the molten metal in the holding furnace so that the level of the molten metal in the tundish is kept substantially constant. In the configuration provided with the control valve for controlling the temperature, a certain amount of molten metal can be gradually supplied between the rolling rolls while maintaining a predetermined temperature, and the above-described excellent quality metal plate can be easily and properly formed. Can be done.

  Further, in the configuration in which the horizontal supply nozzle described above is provided with side dams on both sides of the supply path for supplying the molten metal, which prevents the molten metal flowing through the supply path from protruding in both directions, Almost all of the molten metal supplied from the horizontal supply nozzle can be formed as a metal plate, and the material production efficiency can be made extremely high.

It is a vertical section side view showing molten metal direct rolling device 1 of this embodiment example. It is an enlarged view showing the arrangement state of the horizontal supply nozzle 12. FIG. 3 is a cross-sectional view of the horizontal supply nozzle 12 taken along the line M-M′ shown in FIG. 2. It is a schematic diagram showing the positional relationship between the horizontal supply nozzle 12 and the upper and lower rolling rolls 21 and 22. It is explanatory drawing showing the fitting convex peripheral part 24 of the upper side rolling roll 21, and the concave peripheral groove 25 of the lower side rolling roll 22. 9 is a chart showing the results of evaluation of the bakeability of the molten metal X and the surface morphology of the metal plate Y with respect to the depth of the depression 28 that forms the convex top surface 26 and the groove bottom surface 27. 9 is a chart showing the results of evaluating the groove inclination angles of the groove side walls 29, 29 of the concave circumferential groove 25, the bakeability of the molten metal X, and the burr formation state of the metal plate Y. It is explanatory drawing showing the apparatus 60 of the conventional structure which tilted the upper and lower rolling rolls 61 and 62 at about 45 degrees.

Explanation of symbols

1 Molten Metal Direct Rolling Device 2 Holding Furnace 4 Tundish 8 Control Valve 11 Horizontal Supply Channel 16 Side Dam 19 Weir 21 Upper Rolling Roll 22 Lower Rolling Roll 24 Fitting Convex Peripheral 25 Concave Circumferential Groove 26 Convex Top Surface (Roll Processing Surface)
27 Bottom of groove (rolled surface)
28 Depression 29 Groove Side Wall 30 Convex Peripheral Wall 31 Lubricant Release Agent Applying Device X Metal Melt Y Metal Plate Y Tilt Angle ω Groove Tilt Angle t Narrowest Distance Between Rolls t ₀ Total Thickness Solidification Starting Thickness

An embodiment of the present invention will be described in detail with reference to the accompanying drawings.
The molten metal direct rolling apparatus 1 of this embodiment is shown in FIG. The molten metal direct rolling apparatus 1 is provided with a holding furnace 2 for holding the molten metal X at a predetermined temperature, and a heater 3 for keeping the stored molten metal X at a predetermined temperature is arranged in the holding furnace 2. Has been done. Further, a tundish 4 is provided side by side with the holding furnace 2. The holding furnace 2 is provided with a protruding upper portion 6 protruding toward the tundish 4 side, and the tundish 4 is provided with a protruding lower portion 7 protruding toward the holding furnace 2 side. A protruding lower portion 7 of the tundish 4 is arranged below the protruding upper portion 6 of the holding furnace 2, and the holding furnace 2 and the tundish are disposed between the lower bottom of the protruding upper portion 6 and the upper surface of the protruding lower portion 7. A communication passage 5 that communicates with 4 is provided. Further, the communication passage 5 is provided with a control valve 8 for converting the communication passage 5 into an open state and a closed state, and an opening/closing operation of the control valve 8 is controlled by a control device (not shown). The control valve 8 can adjust the opening amount of the communication passage 5 according to an instruction from the control device. For example, the amount of the molten metal X sent from the holding furnace 2 to the tundish 4 can be controlled by setting the opening amount to 1/4 opening or 1/2 opening. The control device for controlling the opening and closing of the control valve 8 is provided with a float 10 which is provided in the tundish 4 and floats along the surface of the metal melt X held in the tundish 4. The height of the molten metal surface of X is detected. Then, the control valve 8 is opened and closed according to the position of the molten metal surface so that the molten metal surface is controlled to be almost constant. The tundish 4 is also provided with a heater 3 for holding the retained molten metal X at a predetermined temperature.

  Further, a molten metal X is appropriately added to the holding furnace 2 so that the height of the molten metal X stored in the holding furnace 2 is equal to the height of the molten metal X held in the tundish 4. In comparison, the position is always higher. Thus, when the control valve 8 is opened, the molten metal X flows from the holding furnace 2 into the tundish 4 via the communication passage 5. Furthermore, the control valve 8 is also arranged at a position higher than the surface level of the molten metal X held in the tundish 4. Accordingly, when the molten metal X is held in the holding furnace 2 and the tundish 4, the communication passage 5 is also filled with the molten metal X, so that the control valve 8 is opened and the holding furnace 2 is held. When the molten metal X is supplied from the molten metal X, the molten metal X does not hold air. Therefore, when a molten aluminum alloy is used as the molten metal X, it is possible to prevent the molten aluminum alloy from being oxidized. The holding furnace 2, the tundish 4, the communication passage 5, the control valve 8 and the control device constitute the molten metal supply control means according to the present invention.

  As shown in FIG. 2, the tundish 4 described above is provided with a supply port 9 on the side opposite to the holding furnace 2, and the molten metal X in the tundish 4 is horizontally supplied to the supply port 9. A horizontal supply nozzle 12 is connected along the line. A rolling device 20 including a pair of upper and lower rolling rolls 21 and 22 provided in parallel in the vertical direction along the horizontal direction orthogonal to the horizontal supply nozzle 12 is disposed on the tip 13 side of the horizontal supply nozzle 12. ing. In this rolling apparatus 20, the surface f passing through the rotation axes of the upper and lower rolling rolls 21 and 22 can be tilted from the vertical direction to the opposite side (discharging side) of the tundish 4 within about 45 degrees. The upper and lower rolling rolls 21 and 22 can be tilted. Here, the angle formed by the surface f with respect to the vertical direction is the inclination angle θ of the pair of upper and lower rolling rolls 21 and 22, and the inclination angle θ is about 45 degrees from the vertical direction (0 degree) in the present embodiment. The range up to degrees is shown (see FIG. 4). Further, the rolling apparatus 20 is provided with a control device (not shown) for rotationally controlling the upper and lower rolling rolls 21 and 22, and the upper rolling roll 21 and the lower rolling roll 22 are moved in opposite directions to each other. Control to rotate at the same rotation speed. Here, at the time of forming the metal plate Y, the upper rolling roll 21 and the lower rolling roll 22 are moved in the discharge side direction in which the molten metal X supplied from the horizontal supply nozzle 12 is rolled to form the metal plate Y. Toward each other and rotate each other. That is, on the paper surface of FIGS. 1 and 2, the upper rolling roll 21 is rotated counterclockwise and the lower rolling roll 22 is rotated clockwise. Further, in the rolling device 20, the upper rolling roll 21 is made movable in parallel with the lower rolling roll 22 in the vertical direction along the surface f, and is pressed downward along the surface f. Movable device 23 is also provided.

Here, the lower rolling roll 22 is circumferentially formed with a concave circumferential groove 25 on the roll surface, and the upper rolling roll 21 is circumferentially provided with a fitting convex circumferential portion 24 which can be fitted into the concave circumferential groove 25. (See FIG. 5). Here, the outer peripheral diameter of the groove bottom surface 27 of the concave peripheral groove 25 and the outer peripheral diameter of the convex top surface 26 of the fitting convex peripheral portion 24 have substantially the same diameter. Then, the pair of upper and lower rolling rolls 21 and 22 are provided with the concave circumferential groove 25 of the lower rolling roll 22 and the fitting convex of the upper rolling roll 21 on the surface f passing through both the rotational axes P ₁ and P ₂ described above. The fitting convex circumferential portion 24 is fitted into the concave circumferential groove 25 so that the distance from the circumferential portion 24 becomes the shortest (see FIG. 4). Here, the circumferential position in which the concave circumferential groove 25 and the fitting convex circumferential portion 24 are fitted sequentially changes in rotation along the circumferential direction as the upper and lower rolling rolls 21 and 22 rotate. There is. Then, the plate thickness of the metal plate Y to be formed by the molten metal direct rolling apparatus 1 can be set by appropriately adjusting the minimum distance t between the rolls having the smallest distance between the two.

  Further, as shown in FIG. 5, the convex top surface 26 of the fitting convex peripheral portion 24 of the upper rolling roll 21 and the groove bottom surface 27 of the concave peripheral groove 25 of the lower rolling roll 22 respectively cover the entire area in the circumferential direction. A large number of minute recesses 28 are formed substantially uniformly. The convex top surface 26 and the groove bottom surface 27 are roll processing surfaces according to the present invention. Here, the depressions 28 are formed such that the depth Ra thereof is in the range of about 0.5 μm or more and 5.0 μm or less, and a shape in which the depressions 28 adjacent to each other in a microscopic view are smoothly continuous. Has become. As a result, the convex top surface 26 and the groove bottom surface 27 do not cause seizure even when the molten metal X comes into contact with each other without applying a release agent, and solidified molten metal (hereinafter, solidified metal) x It can be possible to start the rolling process by sending the sheet to the discharge side without slipping. Further, the metal plate Y can be molded as one having an appropriately smooth and glossy surface. It will be described in detail later that the convex top surface 26 and the groove bottom surface 27 have a shape in which a large number of depressions 28 are formed.

  Furthermore, as shown in FIG. 5, the concave circumferential groove 25 of the lower rolling roll 22 is provided with groove side walls 29, 29 that are inclined outwardly on both sides. Here, the groove inclination angle (draft) ω of the groove sidewalls 29, 29 is formed to be in the range of about 3 degrees or more and about 10 degrees or less. Thus, the solidified metal x, which is sequentially supplied from the horizontal supply nozzle 12 and solidified by the groove sidewalls 29, 29 that are inclined outward, is rolled by the upper rolling roll 21 and the lower rolling roll 22 with a large clamping force. When the roll is bent, a widening deformation extending in the roll width direction is formed in the gap between the groove side walls 29, 29 and the convex peripheral walls 30, 30 of the fitting convex peripheral portion 24 along the groove inclination angle ω. Can be suppressed by. As a result, the force directly acting on the groove side walls 29, 29 can be reduced, so that the lubricant release agent applied to the groove side walls 29, 29 can be prevented from being damaged, and the solidified metal x can be prevented. It is possible to prevent seizure on the groove side walls 29, 29. Further, by the groove side walls 29, 29 of the concave circumferential groove 25, the rolled metal plate Y can be discharged straight without being wound around the rolling rolls 21, 22, and the metal plate Y can be continuously formed.

  Circulation paths 35, 35 for circulating cooling water inside the rolls are formed in the upper rolling roll 21 and the lower rolling roll 22, respectively, and the concave circumferential groove 25 of the lower rolling roll 22 and the upper rolling roll 21 are formed. The inwardly projecting peripheral portion 24 is indirectly cooled. With this internal water-cooled structure, when the molten metal X supplied from the horizontal supply nozzle 12 comes into contact with the roll surface, it is rapidly cooled and solidified. As will be described later, the molten metal direct rolling apparatus 1 of the present embodiment performs rolling at a large reduction ratio corresponding to normal hot rolling, and therefore the upper and lower rolling rolls 21 and 22 are large. Rolling load acts. Therefore, the rolling rolls 21 and 22 need to have high cooling capacity and sufficient strength. Therefore, the upper and lower rolling rolls 21 and 22 are so-called sleeve-type water-cooled rolls that are optimally designed by using an alloy tool steel having both strength and thermal conductivity.

  Further, in the molten metal direct rolling apparatus 1 of the present embodiment example, as shown in FIG. 2, the convex peripheral walls 30, 30 formed on both sides of the fitting convex peripheral portion 24 of the upper rolling roll 21 and the lower rolling roll 22 are provided. A lubrication release agent application device 31 for applying a paste-form lubrication release agent is provided on the groove side walls 29, 29 of the concave circumferential groove 25. The lubricant release agent applying device 31 includes a release agent supply source that holds a lubricant release agent (not shown), a supply pipe 32 that supplies a predetermined lubricant release agent from the release agent supply source, A coating part 33 that is connected to the most downstream end of the supply pipe 32 and applies the lubricant release agent supplied from the supply pipe 32 to the convex peripheral walls 30, 30 and the groove side walls 29, 29, and a lubricant release agent from the release agent supply source. It is composed of a control device (not shown) that controls the supply amount of the mold agent. Here, the coating part 33 is supported and fixed by a coating casing 34 so that the lubricating mold release agent can be stably coated on the convex peripheral walls 30, 30, and the groove side walls 29, 29. It is connected to the supply pipe 32 inside. The coating housing 34 is on the outlet side of the metal plate Y formed by the upper rolling roll 21 and the lower rolling roll 22 (the inclined side of the upper and lower rolling rolls 21 and 22), and the coating portion 33 includes the convex peripheral walls 30, 30 and the side walls 29, 29 of the groove are respectively arranged at four adjacent locations so as to come into contact with the side walls 29, 29. Further, the application portion 33 has a brush-like shape, and allows the lubricant release agent to be applied to the convex peripheral walls 30, 30 and the groove side walls 29, 29 substantially uniformly and smoothly. The amount of supply from the release agent supply source is controlled by the control device so that the convex peripheral walls 30, 30 and the groove side walls 29, 29 are always in a state where a substantially constant amount of the lubricant release agent is applied. Controlled appropriately. As a result, the release effect of the lubricant release agent is always properly exerted, and the solidified metal x is prevented from sticking to the convex peripheral walls 30, 30 and the groove side walls 29, 29.

Further, as described above, the horizontal supply nozzle 12 connected to the supply port 9 formed on the side portion of the tundish 4 opposite to the holding furnace 2 has a horizontal molten metal X flowing from the tundish 4. The supply path 11 is formed along the horizontal direction. As shown in FIGS. 2 and 3, the horizontal supply path 11 is composed of a road bottom portion 15 formed along the horizontal direction and side dams 16 and 16 standing on both sides of the road bottom portion 15. Here, the horizontal supply nozzle 12 is arranged so as to be orthogonal to the pair of upper and lower rolling rolls 21 and 22 described above. Then, the tip 13 of the road bottom portion 15 of the horizontal supply nozzle 12 is, as shown in FIG. 2, on the side opposite to the inclination direction of the plane f passing through the respective rotation axis P ₁ , P ₂ of the upper and lower rolling rolls 21, 22. It is fitted into the concave circumferential groove 25 of the lower rolling roll 22 described above, and is arranged in a non-contact manner with the groove bottom surface 27 of the concave circumferential groove 25 with a slight gap (see FIG. 4). Here, the tip 13 of the horizontal supply nozzle 12 is arranged on the supply side with respect to the top portion (upper circumferential position in the vertical radial direction) of the lower rolling roll 22. In this way, since the road bottom portion 15 of the horizontal supply nozzle 12 is arranged with a small gap, it does not hinder the rotation of the lower rolling roll 22, and the lower rolling roll 22 prevents the rotation of the lower rolling roll 22. The horizontal supply path 11 is prevented from being cooled. Here, since the tip 13 of the horizontal supply nozzle 12 can be arranged at an arbitrary position on the supply side from the apex portion of the lower rolling roll 22, the molten metal X and the lower rolling roll 22 are initially arranged in accordance with this position. The contact start end B ₂ (see FIG. 4) that comes into contact with is determined. On the other hand, the contact start end B ₁ (see FIG. 4) at which the molten metal X first contacts the upper and upper rolling rolls is determined by the height of the molten metal surface of the horizontal supply nozzle 12. Therefore, the contact circumferential lengths L ₁ and L ₂ (see FIG. 4) of the solidified metal x, which comes into contact with the upper and lower rolling rolls 21 and 22 with the rolling rolls, respectively, can be set to the same arbitrary length. It is possible.

  A heat insulating material (not shown) is provided on the inner peripheral surfaces of the road bottom portion 15 and the side dams 16, 16 which constitute the horizontal supply path 11 so that the molten metal X flowing through the horizontal supply path 11 is not solidified. ing. Further, the side dam 16 of the horizontal supply nozzle 12 does not fit into the concave circumferential groove 25, and the tip side portion 17 of the side dam 16 follows the surface arc shape of each of the upper and lower rolling rolls 21 and 22 so as to have the above-mentioned inter-roller gap. It is provided so as to project to a position immediately before the position at which the narrow distance is t. The tip side portion 17 of the side dam 16 prevents the molten metal supplied to the concave circumferential groove 25 from protruding laterally. The horizontal supply passage 11 of the horizontal supply nozzle 12 is formed to have a width that is substantially the same as the width of the concave circumferential groove 25 of the lower rolling roll 22, and extends from the horizontal supply passage 11 to the entire groove width of the concave circumferential groove 25. The molten metal X is supplied almost evenly. As a result, the metal plate Y can be stably formed to have a substantially uniform plate thickness and a morphology in the plate width direction, and can be formed in a substantially straight shape with high flatness. ..

By the horizontal supply nozzle 12 and the molten metal supply control including the holding furnace 2, the tundish 4 and the like, the molten metal X is gently and upwardly rolled at a predetermined constant surface level. It is adapted to be supplied between the fitting convex peripheral portion 24 of the roll 21 and the concave peripheral groove 25 of the lower rolling roll 22. Here, since the height of the molten metal X is kept constant, the contact start point B ₁ (see FIG. 4) that comes into contact with the upper rolling roll 21 at the same time is always almost at the same position. Since the position where the solidified metal x solidified by the rolls 21 and 22 respectively meet and the solidification is completed (the position where the total thickness solidification starting end thickness t _{0 in} FIG. 4 is reached) is also always determined, the solidified metal x is always reduced at a substantially constant pressure. Depending on the rate, it can be rolled. Therefore, the metal plate Y can be stably formed into a desired plate thickness, texture form, or the like. Further, since the molten metal X is supplied quietly while always maintaining a calm state, bubbles and the like are not generated in the molten metal X, and turbulence such as wavy surface may occur. Absent. Therefore, the metal plate Y can be molded without causing internal defects or wrinkle-like surface defects.

  The horizontal supply nozzle 12 is provided with a weir 19 on the horizontal supply path 11 and on the upper side of the horizontal supply path 11. The weir 19 is formed to have a width substantially the same as the width of the horizontal supply passage 11, and is provided so as to be fitted into the horizontal supply passage 11. Here, below the weir 19, that is, on the lower side of the horizontal supply path 11, the horizontal supply path 11 communicates, and the molten metal X is supplied between the upper and lower rolling rolls 21 and 22 through this lower side. ing. By this weir 19, the molten metal X flowing through the horizontal supply path 11 can be dammed on the molten metal X side and the impurities floating in the molten metal X can be dammed, so that the metal plate Y can be prevented from being mixed with impurities. High quality can be maintained.

An arrangement mode of the horizontal supply nozzle 12 and the upper and lower rolling rolls 21 and 22 for continuously forming a desired metal plate Y by the molten metal direct rolling apparatus 1 will be described with reference to the schematic diagram of FIG.
The upper rolling roll 21 and the lower rolling roll 22 are arranged such that the plane f passing through the rotational axes P ₁ and P ₂ of both rolls is inclined from the vertical direction to the discharge side by a predetermined angle. Here, the angle of the surface f with respect to the vertical direction is the inclination angle θ. The narrowest rolling edge A ₁ of the fitting convex circumferential portion 24 of the upper rolling roll 21 and the narrowest rolling edge A ₂ of the concave circumferential groove 25 of the lower rolling roll 22 on this surface f are The distance is the narrowest, and the distance between the narrowest rolling edges A ₁ and A ₂ is the narrowest distance t between rolls. Further, the arc length of the roll outer circumference from the narrowest rolling end A ₂ of the concave circumferential groove 25 of the lower rolling roll 22 to the position (contact start end) B ₂ where the tip 13 of the horizontal supply nozzle 12 described above is arranged. Is the contact circumference L ₂ . The angle forming the contact circumference L ₂ is the molten metal contact angle φ. Further, an arc of the roll outer circumference from the narrowest rolling end A ₁ of the fitting convex peripheral portion 24 of the upper rolling roll 21 to the position (contact start end) B ₁ where the molten metal surface of the molten metal X flowing through the horizontal supply nozzle 12 comes into contact. The length is the contact circumference L ₁ , and the contact circumference L ₁ is made substantially equal to the contact circumference L ₂ of the lower rolling roll 22. That is, the angle forming the contact circumference L ₁ is also the molten metal contact angle φ. In this way, the molten metal at the position (contact start end) B ₂ of the lower rolling roll 22 where the tip 13 of the horizontal supply nozzle 12 is arranged so that the contact circumference L ₁ and the contact circumference L ₂ are equal to each other. The molten metal depth h ₀ is set. Incidentally, the molten metal X which is supplied from the horizontal supply nozzle 12, the contact start B ₂ and contact starting B ₁ in contact with each solidified and, fitting the convex peripheral section 24 of the upper rolling roll 21 of the lower rolling roll 22 It is bitten by the concave circumferential groove 25, sequentially fed the distances of the contact circumferential length L ₁ and the contact circumferential length L ₂ , respectively, and the rolling process is performed.

Here, at the above-mentioned molten metal contact angle φ, as described above, the solidified metal x solidified by contacting the upper and lower rolling rolls 21 and 22 does not slip with the rolling rolls 21 and 22. It is necessary to sequentially feed in the direction from the contact starting ends B ₁ and B ₂ to the narrowest rolling ends A ₁ and A ₂ (discharging side direction) by sufficient frictional force. This is determined by the biting condition set from the friction coefficient μ between the rolling rolls 21 and 22 and the solidified metal x (see the above-mentioned formula (1)). Further, the inclination angle θ of the upper and lower rolling rolls 21 and 22 is equal to or more than the molten metal contact angle φ because the tip 13 of the horizontal supply nozzle 12 is arranged on the supply side from the top portion of the lower rolling roll 22. (See the above formula (2)). Further, in the convex top surface 26 of the fitting convex peripheral portion 24 and the groove bottom surface 27 of the concave peripheral groove 25 of the upper and lower rolling rolls 21 and 22, as described above, the depression of Ra about 0.5 to 5.0 μm is provided. In the present embodiment, the friction coefficient μ is approximately 0.2 to 0.4. From these conditions (see the above formula (3)), the upper limit value of the inclination angle θ of the upper and lower rolling rolls 21 and 22 was set to about 45 degrees with respect to the vertical direction.

Further, since the tip 13 of the horizontal supply nozzle 12 is arranged in a non-contact state with a slight gap with the lower rolling roll 22, the molten metal X is not inserted into this gap to prevent leakage of molten metal. Is a condition. This condition is determined by the distance h _S between the contact start end B ₁ and the contact start end B ₂ so that the above-mentioned molten metal depth h ₀ does not exceed a critical value determined by this gap and the surface tension of the molten metal (above-mentioned. (Equation (4)). Therefore, the lower limit of the inclination angle θ is set to 0 degree (vertical direction) on condition that the distance h _S is sufficiently smaller than the critical value. It should be noted that the larger the lower limit value, the safer the molten metal X is from being inserted and the safer it is.

  Under these conditions, in the molten metal direct rolling apparatus 1 of the present embodiment, the inclination angle θ of the upper and lower rolling rolls 21 and 22 is in the range from the vertical direction to about 45 degrees toward the discharge side.

Further, the molten metal X supplied from the horizontal supply nozzle 12 arranged in this way is solidified at the contact starting end B ₁ that contacts the upper rolling roll 21 and the contact starting end B ₂ that contacts the lower rolling roll 22. Be started. Then, when the upper and lower rolling rolls 21 and 22 are sequentially fed toward the narrowest rolling ends A ₁ and A ₂ , the space between the upper rolling roll 21 and the lower rolling roll 22 becomes gradually narrower. The solidified metal x solidified on the upper and lower sides meets each other to complete solidification. That is, it solidifies in the entire region in the plate thickness direction. Then, the solidified metal x is further sent in the plate working direction in the entire area in the plate thickness direction to be rolled. Here, the contact peripheries L ₁ and L ₂ contacting the solidified metal x from the contact start ends B ₁ and B ₂ to the narrowest rolling ends A ₁ and A ₂ forming the narrowest distance t between rolls are equalized. By doing so, the molten metal X is solidified equally on both the upper and lower surfaces, so that it has a vertically symmetrical solidified form. Therefore, the solidified metal x can be equally rolled in the vertical direction along the plate thickness direction. Thereby, the metal plate Y having a symmetrical structure in the plate thickness direction can be formed.

On the other hand, the rolling process is the full thickness solidification in which the narrowest roll distance t between the upper and lower rolling rolls 21 and 22 and the solidified metal x in contact with the upper and lower rolling rolls 21 and 22 meet each other to complete the solidification. The rolling reduction ((1-t/t ₀ )×100%) of the rolling process is determined by the difference from the starting end thickness t ₀ . In the molten metal direct rolling apparatus 1, the reduction ratio can be set to about 40% or more, and the molten metal X is rapidly solidified, and at the same time, a large clamping force (corresponding to general hot rolling) is applied. By rolling with a rolling load), a metal plate Y can be formed from the molten metal X in one step. As described above, by setting the rolling reduction to a high value of about 40% or more, the dendrites formed during solidification are modified into a work structure elongated in the longitudinal direction, and microvoids that may be formed during solidification or immediately after the start of rolling, Internal defects such as cracks and surface defects such as ripple marks can be repaired by pressure bonding or smoothing to form a metal plate of excellent quality. Here, in this embodiment, the rolling reduction is set to about 50% or more so that the working effect of the rolling process can be further enhanced. As described above, this reduction rate is determined by the narrowest roll distance t and the total thickness solidification starting end thickness t _0. Therefore, the plate thickness design of the metal plate Y and the roll diameters of the upper and lower rolling rolls 21 and 22 are determined. It can be set at any time by appropriately setting the inclination angle θ, the contact circumferential lengths L ₁ and L ₂ , and the like.

The level of the molten metal X flowing through the horizontal supply passage 11 of the horizontal supply nozzle 12 is the depth of the molten metal X at the contact start end B ₂ where the tip 13 of the horizontal supply nozzle 12 is arranged. It is defined by h ₀ . Further, the inside of the tundish 4 is maintained at the same level so that the level of the level of the molten metal can be sequentially supplied while being kept substantially constant. As described above, by controlling the opening/closing of the control valve 8 as described above, the molten metal X flows from the holding furnace 2 into the tundish 4, and the molten metal X in the tundish 4 is moved to the above-mentioned surface level. Always trying to keep up. As a result, a constant amount of molten metal X can be gently supplied between the upper and lower rolling rolls 21 and 22 while maintaining a calm state.

On the other hand, the outer diameters of the upper and lower rolling rolls 21 and 22 are set so that the rolling load applied during rolling is large enough for practical use. Here, when a rolling roll having a large outer diameter is used, the rolling load becomes relatively large as the outer diameter is increased. For this reason, the entire apparatus is enlarged, and there are many adverse effects on the installation in the factory. On the other hand, when a small mill roll having an outer diameter, the outer diameter dimension for contacting the circumference of the molten metal X L _1, L ₂ becomes shorter accordingly smaller diameter, the total thickness solidification starting thickness t ₀ of the above The distance between the position and the narrowest rolling ends A ₁ and A ₂ forming the narrowest distance t between the rolls becomes short, and it becomes impossible to obtain a sufficient working effect by the rolling work. From the above, the outer diameters of the upper and lower rolling rolls 21 and 22 are set within a practical range to some extent, and the outer diameters of the rolls are usually used for rolling of molten metal. Then, the inclination angle θ, the molten metal contact angle φ, etc. are set as described above according to the upper and lower rolling rolls 21 and 22 of this size, and the molten metal X is supplied by the horizontal supply nozzle 12 to obtain the molten metal. By making the contact circumferential lengths L ₁ and L ₂ of X and the rolling rolls 21 and 22 equal, the practical molten metal direct rolling apparatus 1 according to the present invention is configured.

Next, as described above, the convex top surface 26 of the upper rolling roll 21 and the groove bottom surface 27 of the lower rolling roll 22 (see FIG. 5) in which a large number of minute recesses 28 are formed will be described.
When the metal plate Y is formed from the molten metal X, the recess 28 prevents seizure on the upper and lower rolling rolls 21 and 22 and allows the solidified metal x to be appropriately caught without slipping. The plate Y is provided so as to have an appropriately smooth and glossy plate surface. The recess 28 has a depth of Ra in the range of about 0.5 to 5.0 μm, and the recesses adjacent to each other are formed so as to be continuous smoothly in a microscopic view.

  In this embodiment, the convex top surface 26 and the groove bottom surface 27 are formed by shot peening. The shot peening process is performed by using substantially uniform spherical shot particles having hardness equal to or higher than the materials of the fitting convex peripheral portion 24 and the concave peripheral groove 25 of the upper and lower rolling rolls 21 and 22. Here, the shot particles having a diameter of about 50 to 150 μm are used, and the shot particles are circumferentially formed on the convex top surface 26 and the groove bottom surface 27 at a jetting speed of about 150 to 300 mm/sec. Inject almost uniformly. As a result, minute recesses 28 having a depth of Ra of about 0.5 to 5.0 μm are formed so that adjacent ones are smoothly continuous. Here, during the shot peening process, shot grains collide with the convex top surface 26 and the groove circumferential surface 27 to raise the surface temperature of these to the A3 transformation point. When the surface temperature reaches the A3 transformation point in this way, the quenching action can be performed, so that the durability of the convex top surface 26 and the groove peripheral surface 27 can be improved. In this way, the convex top surface 26 and the groove peripheral surface 27 are formed in a surface form in which a large number of minute recesses 28 are formed.

  Here, the depth range of the depression 28 is an experiment in which upper and lower rolling rolls having depressions 28 of different depths formed on the convex top surface 26 and the groove bottom surface 27 are prepared, and the metal plate Y is formed from the molten metal X, respectively. And set the applicable range. In this experiment, the above-described molten metal direct rolling apparatus 1 was used, the inclination angle θ of the upper and lower rolling rolls was set to about 25 degrees, and the rolling reduction was set to about 50%, and the formability in the case of forming the metal plate Y was examined. .. The result is shown in FIG. In each of the upper and lower rolling rolls, the convex top surface and the groove bottom surface (roll processing surface) are formed by the shot peening processing described above. As a result, when the depth of the depression is smaller than Ra of about 0.5 μm, the upper and lower rolling rolls 21 and 22 slip with the solidified metal x contacting the convex top surface and the groove bottom surface and rotate. According to the above, it cannot be fed properly toward the discharge side. That is, the solidified metal x cannot be caught between the convex top surface and the groove bottom surface. When Ra is about 0.5 μm, there are cases where slip does not occur and cases where slip easily occurs depending on conditions such as the inclination angle θ and the molten metal contact angle φ. On the other hand, when the depth of the depression was larger than Ra about 5.0 μm, seizure occurred on the solidified metal x and the convex top surface and the groove bottom surface. When Ra was about 5.0 μm, there were cases where seizure did not occur and cases where seizure occurred easily depending on conditions such as the inclination angle θ and the molten metal contact angle φ. Then, by setting the depth of the recess to be Ra about 0.5 μm or more and about 5.0 μm or less, the solidified metal x is appropriately bitten without slipping, and is sequentially rotated according to the rotation of the upper and lower rolling rolls 21 and 22. It can be fed in the plate processing direction, and the solidified metal x can be prevented from being seized on the convex top surface or the groove bottom surface. Further, by setting the depth of the depression in such a range, the metal plate Y can be molded as having a moderately smooth and glossy plate surface. In FIG. 6, a case where defective biting or seizure occurs is indicated by “x”, and a case where bite or seizure does not occur depending on conditions is indicated by “Δ”, so that the bite is properly performed and seizure is prevented. When possible, it is indicated by "○".

Further, even if Ra is in the range of about 0.5 to 5.0 μm, if the maximum depth Rmax includes one exceeding about 15 μm, seizure occurs locally or a formed metal plate. A dull glossy part locally occurs on the Y plate surface. Therefore, it is also necessary to set Rmax to about 15 μm or less. On the other hand, if the minimum depth Rmin is smaller than about 0.2 μm, the solidified metal x cannot be bitten over the entire contact circumferential lengths L ₁ and L ₂ , so that continuous molding is performed. In this case, troubles such as defective biting may occur. Therefore, it is necessary to set Rmin to about 0.2 μm or more. In this way, the recess 28 is formed so as to satisfy Rmax and Rmin.

  The same experiment was also performed when the inclination angle θ of the upper and lower rolling rolls was appropriately set within the range of about 45 degrees from the vertical direction to the discharge side. As a result (not shown), it was found that the depth of the depression 28 should be Ra about 0.5 to 5.0 μm, as in the case where the inclination angle θ is about 25 degrees described above.

  Further, in the molten metal direct rolling apparatus 1 according to the present invention, by arranging the upper and lower rolling rolls 21 and 22 having the convex top surface 26 in which such a depression 28 is formed and the groove bottom surface 27, Even with a large reduction rate (about 50%), seizure of the molten metal X can be prevented and the solidified metal x can be sequentially and appropriately fed in the plate processing direction, so that a metal plate Y of excellent quality can be stably and continuously formed. It can be molded.

Next, the groove side walls 29, 29 provided on both sides of the concave circumferential groove 25 formed around the lower rolling roll 22 will be described. A lubrication release agent for preventing the molten metal X from being seized is applied to the side peripheral walls 29, 29 by a lubrication release agent application device 31.
In the groove side walls 29, 29, as shown in FIG. 5, a groove inclination angle ω of about 3 degrees or more and about 10 degrees or less is outward with respect to the direction orthogonal to the groove bottom surface 27 of the concave circumferential groove 25. It is provided so as to be inclined. By providing such groove side walls 29, 29, the solidified metal x which is in contact with the concave circumferential groove 25 and the fitting convex circumferential portion 24 of the upper rolling roll 21 undergoes widening deformation in the roll width direction due to rolling. Can be suppressed. The force of the width-widening deformation can be released into the gap between the groove side walls 29, 29 and the convex peripheral walls 30, 30 of the fitting convex peripheral portion 24 along the direction of the groove inclination angle ω. The force acting on the side walls 29, 29 can be reduced, and further, the friction between the solidified metal x and the side walls 29, 29 of the groove caused by this force can be suppressed. As a result, it is possible to prevent the lubricant release agent applied to the groove sidewalls 29, 29 from being damaged by the force of the width-spreading deformation. It can be exerted, and the solidified metal x can be prevented from being seized on the groove side walls 29, 29. Further, the formed metal plate Y can be discharged straight without being wound around a rolling roll and can be continuously formed with a constant width.

  Here, it has been verified through experiments that the groove inclination angle ω of the groove side walls 29, 29 can appropriately exhibit the above-described effects. In the experiment, the metal plate Y is formed by gradually changing the groove inclination angle ω from about 0 degrees orthogonal to the groove bottom surface 27, baking of the solidified metal x occurs, and burrs formed on both side ends of the metal plate Y. I tried to find out. In this experiment, the molten metal direct rolling apparatus 1 described above was used, the inclination angle θ of the upper and lower rolling rolls was about 25 degrees, and the rolling reduction was about 50%. Further, a graphite grease-based lubricant release agent is applied to the groove side wall and the convex peripheral wall of the fitting convex peripheral portion. The results of this experiment are shown in FIG. When the groove inclination angle ω of the groove side wall was about 0 degree, a high surface pressure was generated between the metal plate and the groove side wall to cause seizure, and the metal plate was wound around the lower rolling roll. Further, when it was set to about 3 degrees, there was a tendency that seizure easily occurred between the metal plate and the side wall of the groove depending on the experimental conditions, but it was generally good. Further, when it is set to about 5 degrees, seizure does not occur between the metal plate and the side wall of the groove, and burrs generated on both side ends of the metal plate are relatively small, and the shape of both side ends is good. It was Further, in the range of about 8 degrees to about 10 degrees, the burr tends to increase depending on the experimental situation, but seizure does not occur. On the other hand, when the angle is set to about 10 degrees, the gap between the groove side wall and the convex peripheral wall is large, and therefore the lower rolling roll is likely to come off. However, since relatively thick and large burrs were formed along the upper rolling roll, there was a tendency to easily wind around the upper rolling roll depending on the experimental conditions, but it was generally good. On the other hand, when it exceeded about 10 degrees, thick and large burrs were formed along the upper rolling roll, and the metal plate was wound around the upper rolling roll. From the above experimental results, it was decided that the groove side walls 29, 29 forming the concave circumferential groove 25 are inclined outward at the groove inclination angle ω of about 3 degrees or more and about 10 degrees or less. Thus, by providing such groove side walls 29, 29, it is possible to prevent the solidified metal x from sticking to the groove side walls 29, 29 and to obtain the metal plate Y to be formed in a relatively straight form. It becomes possible and can be made highly practical. Further, it is possible to prevent a trouble at the time of molding due to the occurrence of the seizure or the formation of burrs.

  The same experiment was also performed when the inclination angle θ of the upper and lower rolling rolls was appropriately set within the range of about 45 degrees from the vertical direction to the discharge side. As a result (not shown), as in the case where the inclination angle θ is about 25 degrees, the seizure occurs by setting the groove inclination angles ω of the groove side walls 29, 29 to about 3 degrees or more and about 10 degrees or less. The metal plate Y can be formed in a straight shape.

Next, a process of continuously producing the metal plate Y from the molten metal X of the aluminum alloy by using the molten metal direct rolling apparatus 1 described above will be described.
Here, in the molten metal direct rolling apparatus 1, use is made of rolling rolls 21 and 22 in which the outer diameter of the fitting convex peripheral portion 24 of the upper rolling roll 21 and the concave circumferential groove 25 of the lower rolling roll 22 is approximately 450 mm. I was there. As described above, the convex top surface 26 of the fitting convex peripheral portion 24 and the groove bottom surface 27 of the concave peripheral groove 25 have minute recesses 28 having a depth Ra of about 2.4 μm substantially evenly along the circumferential direction. It has a large number of shapes. The Rmax of the depression 28 was about 7.0 μm, and the Rmin was about 0.3 μm. Then, the inclination angle θ of the upper and lower rolling rolls 21 and 22 was set to about 25 degrees. Further, the narrowest distance t between the upper and lower rolling rolls 21 and 22 is set so that the metal plate Y having a plate thickness of about 6 mm is formed. The narrowest distance t between the rolls is determined by moving the upper rolling roll 21 up and down by the roll moving device 23. Further, according to these, the molten metal contact angle φ is set to about 30 degrees, the tip 13 of the horizontal supply nozzle 12 is arranged in a non-contact state on the lower rolling roll 22, and the contact peripheral length L ₂ and the contact peripheral length L _{1 are set.} Doo is to be equal, define the melt depth h ₀ of the molten metal X at position (contact start) B ₂ of the tip 13. The level of the molten metal, which is the molten metal depth h ₀ , is always kept constant in the tundish 4 and the horizontal supply passage 11 of the horizontal supply nozzle. Here, in order to maintain the level of the molten metal in the tundish 4 and the horizontal supply path 11 constant, the holding furnace 2 moves to the tundish 4 according to the amount of supply between the upper and lower rolling rolls 21 and 22. The molten metal X is flowing in. That is, a control device (not shown) controls the opening/closing of the control valve 8 according to the height position of the float 10 floating on the surface of the molten metal in the tundish 4 to hold the molten metal X held in the holding furnace 2 at a predetermined temperature. Are allowed to flow into the tundish 4 through the communication passage 5. Here, the holding furnace 2 and the heaters 3 of the tundish 4 are operated to hold the molten metal X at about 720°C.

Further, in setting the inclination angle θ, the molten metal contact angle φ, the molten metal depth h _0, etc. of the above-mentioned upper and lower rolling rolls 21 and 22, the solidified metal x solidified by contacting the upper and lower rolling rolls 21 and 22 is encountered. the total thickness solidification starting thickness t ₀ which is formed by complete solidification Te has been adjusted so that reduction ratio relative to the roll between the narrowest distance t is about 50% or more. The rolling reduction is adjusted so that it does not exceed about 70% to prevent an excessive load from acting on the rolling roll.

  Further, the lower rolling roll 22 has the groove width of the concave circumferential groove 25 (the groove width at the groove bottom surface 27) of about 160 mm, and the groove side walls 29, 29 on both sides constituting the concave circumferential groove 25 are about outward. The groove is inclined at a groove inclination angle ω of 5 degrees. Further, the width of the fitting convex peripheral portion 24 of the upper rolling roll 21 is also set so that it can be fitted into the concave peripheral groove 25. The convex peripheral walls 30, 30 of the fitting convex peripheral portion 24 are formed so as to be substantially orthogonal to the convex top surface 26. Further, the groove side walls 29, 29 of the concave peripheral groove 25 and the convex peripheral walls 30, 30 of the fitting convex peripheral portion 24 are lubricated with a graphite-based paste-like lubricant release agent by the lubricant release agent application device 31 described above. Is applied so that the application amount is substantially constant. By applying the lubricant release agent in this way, it is possible to prevent the solidified metal x from being seized. No lubrication release agent is applied to the groove bottom surface 27 of the concave circumferential groove 25 and the convex top surface 26 of the fitting convex circumferential portion 24. Then, the metal plate Y is formed to have a plate width of about 160 mm by such upper and lower rolling rolls 21 and 22. On the other hand, the upper and lower rolling rolls 21 and 22 are rotated in a direction opposite to each other toward the discharge side at a constant rotation speed. Here, the rotation speeds of the upper and lower rolling rolls 21 and 22 are controlled to be equal. Further, the cooling water is circulated through the circulation path 35 formed inside each of the rolling rolls 21 and 22 to cool the concave circumferential groove 25 and the fitting convex circumferential portion 24.

As described above, the molten metal X that has flowed into the tundish 4 from the holding furnace 2 through the communication passage 5 passes through the horizontal supply passage 11 of the horizontal supply nozzle 12 and the fitting convex peripheral portion 24 of the upper rolling roll 21 and the lower side. It is sequentially supplied to the concave circumferential groove 25 of the rolling roll 22. The molten metal X is kept at the above-mentioned level of the molten metal surface at a constant temperature and is kept at a predetermined temperature, and the molten metal X is calm and smooth without causing any disturbance in the molten metal and the molten metal surface, It contacts the convex top surface 26 and the groove bottom surface 27 of the concave circumferential groove 25. Here, the contact start ends B ₁ and B _{2 with} which the molten metal X comes into contact are always substantially constant at the positions set as described above. When the convex top surface 26 and the concave circumferential groove 25 are brought into contact with each other, the molten metal X is rapidly cooled and solidified, and is caught in the convex top surface 26 of the fitting convex circumferential portion 24 and the groove bottom surface 27 of the concave circumferential groove 25. As the rolling rolls 21 and 22 rotate, they are sequentially fed in the discharge side direction toward the narrowest rolling ends A ₁ and A ₂ having the narrowest distance t between the rolls. Here, as described above, the convex top surface 26 and the groove bottom surface 27 have an uneven shape in which a large number of depressions 28 having Ra of about 2.4 μm are formed, so that the solidified metal x and seizure can be prevented. At the same time, the solidified metal x can be appropriately caught, and the solidified metal x can be sequentially fed in the discharge side direction without slipping.

Then, as the upper and lower rolling rolls 21 and 22 rotate, the fitting convex peripheral portion 24 is fitted into the concave peripheral groove 25, and when the distance between the convex top surface 26 and the groove bottom surface 27 becomes gradually narrow, the convex top surface 26 and the groove bottom surface 27 are brought into contact with each other, the solidified metals x, x meet and the solidification is completed. That is, the position where the solidification is completed is the full-thickness solidification starting end where the solidified metal x is completely solidified in the entire plate thickness direction, and the plate thickness at the position is the total thickness solidification starting end thickness t ₀ . Further, as the rolling rolls 21 and 22 rotate, the solidified metal x is gradually clamped and rolled. Then, the solidified metal x is rolled to the narrowest distance t between the rolls to form a desired metal plate Y. Here, as described above, by setting the rolling reduction to about 50% or more, the action of stretching the dendrites generated when the molten aluminum alloy solidifies along the longitudinal direction is further enhanced. Here, the dendrites are formed so as to be substantially orthogonal to the solidification interface (two-dot chain line in FIG. 4) at which the molten metal X solidifies, and therefore, before the rolling process is performed, the plate is formed. It is supposed to be formed so as to incline vertically and vertically from the center toward the plate processing direction. Then, this dendrite is modified into a processed structure that is elongated along the longitudinal direction by rolling. Furthermore, by this rolling process with a large reduction rate, internal defects such as microvoids and cracks that may be generated during solidification or immediately after the start of rolling and surface defects such as ripple marks can be repaired by pressure bonding or smoothing. The metal plate Y is formed to have a high quality capable of exhibiting high mechanical properties by forming such a texture form as a symmetrical structure in the plate thickness direction. Incidentally, when passing the narrowest distance t between the rolls, the convex top surface 26 and the groove bottom surface 27 are separated from each other, and the metal plate Y is released from the convex top surface 26 and the groove bottom surface 27 and discharged. It Since the convex top surface 26 and the groove bottom surface 27 of this embodiment are formed with a large number of depressions 28 having Ra of about 2.4 μm, they also have an excellent releasing effect, and at the time of releasing the mold. The surface of the metal plate Y is not damaged.

  Here, in the state where the rolling process is performed, the solidified metal x tends to be widened and deformed in the roll width direction due to the large clamping force applied by the rolling process, and the solidified metal x is likely to be widened and deformed. Is applied to the groove side walls 29, 29 of the concave circumferential groove 25. As described above, the groove side walls 29, 29 are provided so as to be inclined outward at the groove inclination angle ω (about 5 degrees in the present embodiment example). Therefore, the concave peripheral groove 25 and the convex peripheral groove are provided. By forming a burr in the gap with respect to 30, it is possible to release the force that tends to widen and deform along the inclination direction of the groove inclination angle ω. As a result, the force that acts on the groove side walls 29, 29 to widen and deform can be reduced, and so-called widening can be prevented, so that the frictional force between the groove side walls 29, 29 and the solidified metal x can be suppressed. It is possible to prevent damage such as peeling off of the lubricant release agent applied to the groove side walls 29, 29. Therefore, the solidified metal x can be prevented from sticking to the groove side walls 29, 29. Further, the metal plate Y thus obtained is formed into a straight shape with a substantially constant width, with only small burrs formed on both side ends thereof. For this reason, even when a processing step for adjusting the both ends of the metal plate Y is provided, the processing step only needs to be relatively easy, and the time and labor required for the step can be relatively small. ..

  With the molten metal direct rolling apparatus 1 of the present embodiment, the metal plate Y was formed by about 100 m. During this forming, the groove bottom surface 27 and the groove side walls 29, 29 of the concave peripheral groove 25 of the lower rolling roll 22, and the convex top surface 26 and the convex peripheral walls 30, 30 of the fitting convex peripheral portion 24 of the upper rolling roll 21. No trouble due to image sticking, such as image sticking, occurred. Further, there was no trouble caused by burrs formed on both sides of the metal plate Y, and the metal plate Y could be taken out in a substantially straight shape relatively easily. Then, a substantially constant metal plate Y having a plate thickness of about 6 mm and a plate width of about 160 mm could be continuously formed. The metal plate Y is appropriately smooth over the entire length and is formed on a desired glossy plate surface, and a slight burr is formed on both side edges of the metal plate Y. Yes, it was molded into a good side edge shape. Further, as a result of detailed examination of the metal plate Y, no internal defects, surface defects, etc. were generated over the entire length, and impurities and the like were not mixed. Furthermore, as a result of observing the structure of the metal plate Y, it was found that the structure morphology extended along the longitudinal direction was formed in a symmetrical structure in the plate thickness direction, and that the structure formation was substantially uniform in the width direction. The formation was confirmed over the entire length. Moreover, as a result of evaluating the mechanical properties of the test pieces taken from the metal plate Y at equal intervals in the longitudinal direction, all the test pieces stably exhibited high physical property values. As described above, according to the molten metal direct rolling apparatus 1, the desired metal plate Y can exhibit excellent mechanical properties without causing troubles such as seizure and burrs during forming. As a quality product, stable production is possible.

  On the other hand, as a comparative example with respect to the molten metal direct rolling apparatus 1 of the present embodiment example, the inclination angle θ of the upper and lower rolling rolls 61 and 62 of the above-described conventional configuration shown in FIG. 8 is set to about 45 degrees, and the lower rolling is performed. An apparatus 60 was prepared in which the molten metal X was flown down and supplied to the roll 62. Here, a fitting convex peripheral portion 64 is formed on the upper rolling roll 61 of the conventional configuration, and a concave peripheral groove 65 is formed on the lower rolling roll 62. As in the above-described embodiment example, the fitting convex peripheral portion is formed. 64 can be fitted into the concave circumferential groove 65. The convex top surface 66 of the fitting convex peripheral portion 64 and the groove bottom surface 67 of the concave peripheral groove 65 have a smooth flat shape, and soot is applied as a release agent by incomplete combustion of propane gas. is doing. The groove side wall (not shown) of the concave circumferential groove 65 of the lower rolling roll 62 is formed so as to be substantially orthogonal to the groove bottom surface (not shown) (the groove inclination angle is about 0 degree). The upper and lower rolling rolls 61, 62 are the same rolling rolls as those of the present embodiment except that the shapes of the fitting convex peripheral portion 64 and the concave peripheral groove 65 are different as described above, and the inter-roller narrowest The distance t and the fitting convex peripheral portion 64 have the same shape.

  Further, in the apparatus 60 of this comparative example, the molten metal X that has flowed from the holding furnace 72 into the gutter-shaped tundish 74 is flowed down from the tundish 74 onto the lower rolling roll 62, and the upper and lower rolling rolls 61, 62. It is arranged such that the water is successively supplied to the pool of water generated in the region defined by the side dams 76 arranged between and on both sides. Then, it is supposed that the material is fed in the plate working direction from the inside of the basin as the rolling rolls 61 and 62 rotate. Here, the gutter-shaped tundish 74 is narrower than the groove width of the concave circumferential groove 65 of the upper and lower rolling rolls 61 and 62, and the molten metal X that flows in from the tundish 74 and is supplied to the pool is a roll. It is supposed to spread in the width direction. Further, since the molten metal X is made to flow down onto the lower rolling roll 62, the contact circumference (not shown) at which the molten metal and the upper and lower rolling rolls contact each other is set to the upper rolling roll 61. In comparison, the lower rolling roll 62 is longer.

  Using the apparatus 60 of this comparative example, a metal plate Y′ having a plate width of 160 mm and a plate thickness of about 6 mm was formed as in the above-described embodiment. At about 10 m after the start of molding, seizure of the molten metal occurred, so the molding was stopped. When the seizure-occurring portions of the upper and lower rolling rolls 61 and 62 were examined, the applied release agent was peeled off. Here, the site where the seizure occurred was on the convex top surface 66 of the fitting convex peripheral portion 64 and the groove bottom surface 67 of the concave peripheral groove 65. Further, during this forming, the metal plate Y′ gradually tended to be wound around the lower rolling roll 62. Therefore, as a result of examining the concave circumferential groove 65 of the lower rolling roll 62, the molten metal was burned on the groove side wall (not shown) of the concave circumferential groove 65, and the release agent was peeled off. Therefore, in order to perform further molding, it was necessary to apply the release agent again, and it was found that there is a limit to continuous molding. Further, as a result of examining the formed metal plate Y′ over the entire length, a wrinkle-like defect was found on the surface. It is considered that this is because the molten metal X was made to flow onto the lower rolling roll 62 and then supplied to the pool, so that the surface of the molten metal X was disturbed in the pool such as waviness. .. Further, the release agent was partially adhered to the surface of the metal plate Y', which had a rough surface texture. This is because the release effect of the release agent applied to the convex top surface 66 and the groove bottom surface 67 was reduced as the metal plate Y′ was continuously formed, and the release effect was constantly exhibited. It can be said that it is not possible. On the other hand, as a result of evaluating the mechanical properties of the metal plate Y', the development of the physical property values was lower than that of the metal plate Y'formed by the molten metal direct rolling device 1 of the embodiment. Therefore, as a result of examining the morphology of the metal plate Y', it was found to be asymmetric in the plate thickness direction. Further, the mechanical property values had a relatively large variation in the longitudinal direction, and the tissue morphology was non-uniform in the longitudinal direction as well. It is considered that these are because the upper and lower rolling rolls of the apparatus 60 of this comparative example have different contact circumferential lengths (not shown) with which the molten metal contacts.

  Furthermore, in the metal plate Y'formed by the device 60 of this comparative example, reverse segregation in which the solute is concentrated occurs on the plate surface. On the other hand, in the metal plate Y formed by the molten metal direct rolling apparatus 1 according to the present invention, the generation of this segregation was suppressed as compared with the metal plate Y′ of the comparative example. Therefore, by performing heat treatment such as annealing of the metal plate Y, recrystallization texture is sufficiently generated, and the effect of this heat treatment can be properly exhibited.

As described above, according to the molten metal direct rolling apparatus 1 of the present embodiment, as described above, the internal defects and the surface defects are not generated, and the surface has a smooth and glossy surface and is symmetrical in the plate thickness direction. It is also possible to stably produce a metal plate of excellent quality capable of exhibiting high mechanical properties, which is formed into a uniform structure in the width direction. Further, the molten metal direct rolling apparatus 1 is configured to perform rolling processing by the concave circumferential groove 25 provided with the groove side walls 29, 29 which are inclined outwardly at approximately 3 degrees or more and approximately 10 degrees or less, and the fitting convex circumferential portion 24. Therefore, the lubricant release agent applied to the groove side walls 29, 29 can be prevented from being damaged, and the solidified metal x and the groove side walls 29, 29 can be prevented from seizing. Then, the formed metal plate Y can be formed in a substantially constant width and in a substantially straight shape. Furthermore, in this molten metal direct rolling apparatus 1, the upper and lower rolling rolls 21 and 22 have the convex top surface 26 and the groove bottom surface 27 that form the uneven surface by the depression 28, and the convex top surface 26 and Since the inclination angle θ is set based on the coefficient of friction μ with the groove bottom surface 27, even if the mold release agent is not applied to the convex top surface 26 and the groove bottom surface 27, trouble such as seizure of the molten metal X may occur. In addition to preventing the above, the solidified metal x can be sequentially and properly fed in the direction toward the narrowest rolling edges A ₁ and A ₂ without slipping.

  Further, in the molten metal direct rolling apparatus 1, the molten metal X supplied through the horizontal supply path 11 of the horizontal supply nozzle 12 is supplied to the bottom 15 of the horizontal supply path 11 and the concave circumferential groove of the lower rolling roll 22. It is not inserted into a fine gap with the metal 25, and this fine gap prevents the temperature of the molten metal X in the horizontal supply passage 11 from changing rapidly. Further, the side dams 16, 16 prevent the molten metal X from leaking to the outside of the horizontal supply path 11. Furthermore, the inclination angle θ of the upper and lower rolling rolls 21 and 22 is set based on the frictional force that can be exerted by the convex top surface 26 of the fitting convex peripheral portion 24 and the groove bottom surface 27 of the concave peripheral groove 25 in contact with the solidified metal x. Therefore, the solidified metal x can be bitten and appropriately fed in the plate processing direction. Therefore, this molten metal direct rolling apparatus 1 is excellent in that it is possible to significantly reduce the occurrence of apparatus troubles during molding, defective molding, and the like, and it is also possible to reduce the time and cost required for work such as maintenance of the apparatus. It also has advantages. Thus, the molten metal direct rolling apparatus 1 according to the present invention can be sufficiently put to practical use as a manufacturing apparatus for producing a desired metal plate Y, and has excellent quality and high mechanical properties. The product can be stably produced.

  In the molten metal direct rolling apparatus 1 of the above-described embodiment, the inclination angle θ of the upper and lower rolling rolls 21 and 22 is set to about 25 degrees, but the type of aluminum alloy or other metal, or forming Depending on the plate thickness of the metal plate, etc., it can be appropriately set within the range of about 45 degrees from the vertical direction to the discharge side as described above. Further, the inclination angle θ is preferably in the range of about 10 degrees or more and about 40 degrees or less in consideration of practicality from the shape of the rolling roll, the coefficient of friction, etc., and further about 20 degrees or more. A range of about 30 degrees or less is preferable. The molten metal contact angle φ can be appropriately set according to the inclination angle θ. Furthermore, in the above-described embodiment, the reduction rate is set to be about 50% or more, but it is also possible to appropriately set the reduction rate to be about 40% or more.

  Further, in the molten metal direct rolling device 1 of the above-described embodiment, the groove circumferential wall 25 formed on the lower rolling roll 22 is grooved side wall 29 which is inclined outward at a groove inclination angle ω of about 5 degrees. , 29, but as described above, the groove side wall can be inclined within a range of about 3 degrees or more and about 10 degrees or less. Also by this, similarly to the above, it is possible to prevent the side wall of the groove and the molten metal from being seized and the formation of relatively large burrs, and it is possible to continuously form desired metal plates. The groove inclination angle ω is in the range of about 4 degrees to about 7 degrees so that the effect of preventing seizure and the effect of forming the metal plate in a straight shape can be more appropriately exerted. Is preferred.

Further, in the convex top surface 26 of the fitting convex peripheral portion 24 and the groove bottom surface 27 of the concave peripheral groove 25, minute recesses 28 are uniformly provided in the circumferential direction by the above-mentioned shot peening processing to form irregularities. Although it is formed, it may be formed by another processing method such as etching. In the minute recesses, Ra is about 1.0 μm or more and about 2 μm or more in order to further enhance the function and effect of preventing seizure of the molten metal and the function and effect of forming without slipping and having a desired gloss. It is preferable that the thickness is 0.5 μm or less.

Claims (9)

A pair of upper and lower water-cooled rolling rolls, in which both rotation axes are horizontal and parallel to each other, and a plane passing through both rotation axes is arranged to be vertical or inclined to the discharge side within about 45 degrees,
A horizontal supply path for supplying the molten metal between the upper and lower rolling rolls is formed, and a horizontal supply nozzle arranged in a non-contact state with a fine gap with the roll surface of the lower rolling roll,
A molten metal supply means for sequentially supplying the molten metal held at a predetermined temperature so as to maintain a substantially constant molten metal surface height in the supply path of the horizontal supply nozzle,
The molten metal supplied from the horizontal supply nozzle, from the upper and lower contact start ends contacting the upper rolling roll or the lower rolling roll, to the narrowest rolling end of the narrowest distance between the upper and lower rolling rolls, the upper and lower contact circumferential lengths. The molten metal direct rolling device is characterized in that the lengths are approximately equal. The metal melt supplied by the horizontal supply nozzle and solidified by contact with the pair of upper and lower water-cooled rolling rolls has a rolling reduction of about 40% or more by the rolling rolls ((1-narrowest distance between rolls t/total thickness The molten metal direct rolling apparatus according to claim 1, which is capable of being rolled with a solidification starting thickness t ₀ )×100).   A concave circumferential groove formed around the surface of the lower rolling roll, and a fitting convex circumferential portion formed around the surface of the upper rolling roll that can be fitted into the concave circumferential groove, and between the upper and lower rolling rolls by a horizontal supply nozzle. 3. The metal melt supplied is rolled together with solidification by the groove bottom surface of the concave circumferential groove and the convex top surface of the fitting convex circumferential portion. Molten metal direct rolling device described.   The concave circumferential groove formed on the surface of the lower rolling roll is provided with groove side walls inclined outwardly at about 3 degrees or more and about 10 degrees or less on both sides. Molten metal direct rolling device described.   Lubrication release agent coating device for applying a lubricant release agent to the groove side walls formed on both sides of the concave circumferential groove of the lower rolling roll and the convex circumferential walls formed on both sides of the fitting convex circumferential portion of the upper rolling roll. The molten metal direct rolling apparatus according to claim 3 or 4, further comprising:   A pair of upper and lower water-cooled rolling rolls solidifies the molten metal supplied from the horizontal supply nozzle and rolls it. A large number of minute recesses with Ra of about 0.5 μm or more and about 5.0 μm or less are formed on the roll processing surface. The molten metal direct rolling apparatus according to any one of claims 1 to 5, wherein:   A pair of upper and lower water-cooled rolling rolls are formed by performing shot peening processing with substantially uniform spherical shot grains on the roll processing surface for solidifying and rolling the molten metal supplied from the horizontal supply nozzle. The molten metal direct rolling apparatus according to any one of claims 1 to 6, characterized in that. The molten metal supply means
A tundish connected to the horizontal supply nozzle, which holds the molten metal at the same level as the horizontal supply path of the horizontal supply nozzle;
A holding furnace which communicates with the tundish and holds the molten metal at a predetermined temperature;
The control valve is provided in a communication path between the holding furnace and the tundish, and has a control valve for controlling the inflow of the molten metal in the holding furnace so that the level of the molten metal in the tundish is kept substantially constant. The molten metal direct rolling apparatus according to any one of claims 1 to 7, characterized in that. The horizontal supply nozzle is provided with side dams on both sides of the horizontal supply path for supplying the molten metal to prevent the molten metal flowing through the horizontal supply path from protruding in both directions. 8. The molten metal direct rolling apparatus according to any one of 8.

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