JP5503231B2 - Continuous processing apparatus and continuous processing method for aluminum alloy plate - Google Patents

Description

  The present invention relates to a continuous processing apparatus and a continuous processing method for continuously heating and cooling a rolled aluminum alloy sheet.

  Aluminum alloy plates are used in a wide range of fields such as cans and automobile members because they are lightweight and have excellent formability and corrosion resistance. Aluminum alloy sheets are usually manufactured by performing homogenization heat treatment on an aluminum alloy ingot, followed by hot rolling and cold rolling, etc., but depending on the composition, characteristics such as formability after cold rolling are obtained. A heat treatment is performed for improvement. As a method of this heat treatment, there are a method of heat-treating in a coil form in a batch-type annealing furnace, and a method of heat-treating while conveying an alloy plate with a continuous processing apparatus (continuous annealing line), depending on the required characteristics. It is used properly.

  The aluminum alloy plate is made of an alloy such as 5000 or 6000 as an automobile member. Depending on the application, the aluminum alloy plate may be cold-rolled to a product plate thickness and then processed into an O material (annealed) or solutionized. A quenching process is performed, and such a process often uses a continuous annealing line capable of rapid heating and rapid cooling.

  When an aluminum alloy plate is usually subjected to the above-mentioned homogenization heat treatment, hot rolling, annealing treatment, solution treatment, etc., an oxide film is formed on the surface. This oxide film degrades the degreasing properties of the aluminum alloy plate, causes chemical conversion unevenness during chemical conversion treatment, and lowers the coating appearance and corrosion resistance. Therefore, conventionally, when aluminum alloy sheets are shipped, surface cleaning with acid or alkali has been performed.

  Here, in order to clean the surface of the aluminum alloy plate, a cleaning facility is provided separately from the above-described continuous annealing line, or as shown in Patent Document 1 or Patent Document 2, the cleaning equipment is incorporated in the continuous annealing line. There was a need. That is, in Patent Document 1, it is proposed to dispose a surface treatment device for removing a surface oxide film continuously to a continuous heat treatment device composed of a heating zone and a cooling zone. It has been proposed to pickle an aluminum alloy plate by arranging an acid washing device continuously in the line.

Japanese Patent Laid-Open No. 9-195019 (Claim 2, FIG. 1) JP-A-6-256980 (paragraph 0014, FIG. 1)

  However, if cleaning equipment is provided separately from the continuous annealing line, the process becomes complicated and the productivity may be reduced. In addition, when the cleaning equipment is incorporated in the continuous annealing line as in Patent Document 1 and Patent Document 2, it is necessary to secure a space for installing the cleaning equipment in the continuous annealing line, and the installation of the cleaning equipment is expensive. It was necessary. Here, in recent years, an aluminum alloy has been widely used as a member for an automobile because of its light weight, and has greatly contributed to an improvement in automobile fuel consumption. Therefore, cost reduction is indispensable for further dissemination, and a technology for reducing cost more than the present is necessary.

  This invention is made | formed in view of this point, Comprising: By utilizing the cooling equipment currently used by the existing continuous annealing line, cooling of the aluminum alloy plate after heat processing is not accompanied by a big capital investment. It is an object of the present invention to provide a continuous processing apparatus and a continuous processing method capable of simultaneously and simultaneously performing surface cleaning.

  This inventor repeated earnest experiment and examination in order to solve the above-mentioned subject. As a result, by using an acidic aqueous solution as a cooling medium for rapidly cooling a rapidly heated aluminum alloy plate in a continuous annealing line, the cooling and surface cleaning of the aluminum alloy plate are performed in parallel using existing cooling equipment. And found that it can be implemented.

That is, in order to solve the above-mentioned problems, an aluminum alloy plate continuous processing apparatus according to the present invention is a continuous processing apparatus for continuously heating and cooling an aluminum alloy plate rolled to a desired plate thickness, A heating zone for heating the aluminum alloy plate; and a cooling zone for cooling the aluminum alloy plate heated in the heating zone, wherein the cooling zone uses an acidic aqueous solution as a cooling medium, and the aluminum aqueous solution is formed by the acidic aqueous solution. The cooling of the alloy plate and the surface cleaning for improving the degreasing property of the aluminum alloy plate surface were performed at the same time.

  With such a configuration, the continuous processing apparatus for aluminum alloy plates uses an acidic aqueous solution as a cooling medium in the cooling zone to perform surface cleaning in parallel with the cooling of the aluminum alloy plate, thereby reducing the Mg concentration on the plate surface, The oxide film can be removed.

  Further, in the continuous processing apparatus for an aluminum alloy plate according to the present invention, the acidic aqueous solution is any one of a sulfuric acid aqueous solution, a phosphoric acid aqueous solution, or a mixture thereof, and an acid concentration thereof is 0.005 to 0.005. It is preferably within the range of 3.000% by mass.

  With this configuration, the aluminum alloy plate continuous processing apparatus can reduce the Mg concentration on the surface of the aluminum alloy plate and reduce the thickness of the oxide film to the extent that degreasing failure can be prevented in the subsequent degreasing step.

Furthermore, the continuous processing method of the aluminum alloy plate according to the present invention is a continuous processing method of continuously heating and cooling the aluminum alloy plate rolled to a desired plate thickness, wherein the aluminum alloy plate is placed in a heating zone. A heating step of conveying and heating the aluminum alloy plate, and a cooling step of conveying the heated aluminum alloy plate into a cooling zone and cooling the aluminum alloy plate, wherein the cooling step includes cooling An acidic aqueous solution was used as a medium, and the aluminum alloy plate was cooled and the surface cleaning for improving the degreasing property of the aluminum alloy plate surface was simultaneously performed with the acidic aqueous solution.

  With such a configuration, the continuous treatment method of the aluminum alloy plate uses an acidic aqueous solution as a cooling medium in the cooling zone, performs surface cleaning in parallel with the cooling of the aluminum alloy plate, reduces the Mg concentration on the plate surface, The oxide film can be removed.

  Moreover, the continuous treatment method of the aluminum alloy plate according to the present invention is such that the acidic aqueous solution is any one of a sulfuric acid aqueous solution, a phosphoric acid aqueous solution, or a mixture thereof, and an acid concentration thereof is 0.005 to 0.005. It is preferably within the range of 3.000% by mass.

  With such a configuration, the aluminum alloy plate continuous processing method can reduce the Mg concentration on the surface of the aluminum alloy plate and reduce the thickness of the oxide film to the extent that the degreasing failure in the subsequent degreasing step can be prevented.

  According to the continuous processing apparatus and the continuous processing method of an aluminum alloy plate according to the present invention, the equipment used in the existing continuous annealing line is used as it is, and the cooling and surface cleaning of the aluminum alloy plate after the heat treatment are performed in parallel. Can be done at the same time. Therefore, it is possible to produce an aluminum alloy plate without a new capital investment and an increase in the size of the continuous processing apparatus and with fewer steps than before.

It is the schematic which shows the structure of the continuous processing apparatus which concerns on embodiment.

(Continuous processing equipment)
Hereinafter, the continuous processing apparatus 10 of the aluminum alloy plate which concerns on embodiment is demonstrated, referring drawings. As shown in FIG. 1, the continuous processing apparatus 10 includes an uncoiler 1 that is disposed on the most upstream side and feeds a coiled aluminum alloy plate A (hereinafter referred to as an alloy plate A), a preliminary cleaning device 2, and an accumulator 3. A heating zone 4, a cooling zone 5, a rinsing zone 6, and a recoiler 7 that is disposed on the most downstream side and winds the alloy plate A in a coil shape are provided as main components.

  The continuous processing apparatus (continuous annealing apparatus) 10 having such a configuration continuously heats and cools the alloy sheet A rolled to a desired sheet thickness, and thereby properties such as strength and formability of the alloy sheet A. It is a device for adjusting. The alloy plate A is generally work hardened through cold rolling, and its formability is lowered. However, properties such as formability and bake hardness (characteristics that improve the strength during paint baking in the subsequent process) can be obtained by heating / cooling with the continuous processing apparatus 10, solution treatment / quenching treatment, or annealing treatment. Can be improved.

  The alloy plate A is manufactured by subjecting an aluminum alloy ingot to a uniform heat treatment, followed by hot rolling, cold rolling or the like. The composition of the alloy plate A is not particularly limited. For example, in the case of a 3000 series, 5000 series, 6000 series, etc. aluminum alloy containing Mg, the mechanical properties, surface treatment properties and adhesive properties of the alloy plate A by heating / cooling. Can be expected more.

  The uncoiler (feeding device) 1 is for feeding the coiled alloy sheet A to the downstream side of the continuous processing device 10. The uncoiler 1 is disposed on the most upstream side in the continuous processing apparatus 10. The uncoiler 1 includes a mandrel (not shown) for supporting the coiled alloy plate A and sending means (not shown) for sending the alloy plate A, and the alloy plate A is attached to the precleaning device 2 located downstream. Send it out.

  The preliminary cleaning device 2 is a device for preliminarily cleaning the alloy plate A conveyed from the uncoiler 1. Since the cold rolled oil, dust, dust and the like adhere to the alloy plate A after cold rolling, it is necessary to clean the alloy plate A before heating / cooling by the preliminary cleaning device 2. As shown in FIG. 1, the preliminary cleaning device 2 is disposed between the uncoiler 1 and the upstream accumulator 3a. The medium used for the preliminary cleaning is water, and examples of the cleaning method include a method of cleaning by spraying water, hot water, or the like on both surfaces of the alloy plate A.

  The accumulator 3 is a device for temporarily accumulating the alloy sheet A conveyed through the continuous annealing line and adjusting the feed amount and tension. As shown in FIG. 1, the accumulator 3 includes an upstream accumulator 3 a disposed upstream of the heating zone 4 in the continuous processing apparatus 10, and a downstream accumulator 3 b disposed downstream of the washing zone 6. .

  The upstream accumulator 3 a receives the alloy plate A cleaned by the preliminary cleaning device 2, adjusts the feed amount and tension, and feeds it to the heating zone 4. Then, the downstream accumulator 3b receives the alloy plate A washed with a washing zone 6 described later, adjusts the feed amount and tension, and sends it to the recoiler 7. By providing such an accumulator 3, the continuous processing apparatus 10 can efficiently perform heating / cooling processing and improve productivity.

  The heating zone 4 is for heating the alloy plate A to be conveyed. The heating zone 4 uniformly heats both surfaces of the alloy plate A by blowing hot air at a predetermined temperature, for example, on both surfaces of the alloy plate A. When the alloy sheet A after cold rolling is a heat treatment type alloy such as 6000 series, it is rapidly heated to a predetermined temperature in the heating zone 4 to perform a solution treatment in which undissolved elements are dissolved in the structure. In the case where the alloy sheet A after cold rolling is a non-heat treatment type alloy such as 5000 series, it is rapidly heated to a predetermined temperature in the heating zone 4 to be annealed to recrystallize the structure. The

  The heating temperature in the heating zone 4 (the temperature of the alloy plate A) is set according to the characteristics of the material. For example, in the case of a solution treatment of a 6000 series alloy that is a heat treatment type alloy, about 500 to 550 ° C., non-heat treatment. If it is an annealing treatment of a 5000 series alloy which is a mold alloy, it can be set to about 400 to 500 ° C.

  The cooling zone 5 is provided adjacent to the heating zone 4 and is for cooling the alloy plate A heated in the heating zone 4. The cooling zone 5 uniformly cools both surfaces of the alloy plate A by bringing a cooling medium having a predetermined temperature into contact with both surfaces of the alloy plate A. The alloy plate A heated in the heating zone 4 is rapidly cooled to a predetermined temperature in the cooling zone 5, and particularly when the alloy plate A is a heat treatment type alloy such as a 6000 series alloy, the rapid cooling causes a solid solution at room temperature. A quenching process is performed to keep it.

  Although the cooling method by the cooling zone 5 is not specifically limited, For example, the method of spraying a cooling medium directly on both surfaces of the heated alloy plate A, the method of immersing the heated alloy plate A in a cooling medium, etc. are mentioned. An acidic aqueous solution is used as the cooling medium used in the cooling zone 5. Thus, by using the acidic aqueous solution as the cooling medium, the oxide film on the surface of the alloy plate A can be cleaned and removed in parallel with the cooling of the alloy plate A. As a result, it is possible to improve the degreasing property of the surface of the alloy plate A and to prevent processing unevenness of the chemical conversion treatment.

  As the acidic aqueous solution used in the cooling zone 5, an inorganic acid aqueous solution is used. Specifically, an aqueous sulfuric acid solution, an aqueous phosphoric acid solution, an aqueous nitric acid solution, and the like can be mentioned. Among them, an aqueous sulfuric acid solution, an aqueous phosphoric acid solution, or a mixture thereof is preferably used. The acid concentration of the acidic aqueous solution is preferably in the range of 0.005 to 3.000% by mass in any case, more preferably in the range of 0.01 to 2.00% by mass, More preferably, it is in the range of 0.10 to 2.00% by mass. If the acid concentration of the acidic aqueous solution is less than 0.005% by mass, the desired cleaning ability cannot be obtained. If the acid concentration exceeds 3.000% by mass, the desired cleaning ability can be obtained, but the waste water treatment or continuous treatment apparatus. 10 corrosion resistance, the cost of the acidic aqueous solution, and the like are problems.

  Although the temperature of the acidic aqueous solution (cooling medium) used in the cooling zone 5 is not particularly limited, it is preferably, for example, room temperature to 60 ° C. By setting the temperature of the acidic aqueous solution within such a range, the surface of the alloy plate A can be cleaned and the alloy plate A can be cooled to a desired temperature. Note that the temperature of the acidic aqueous solution is controlled by adjusting the temperature of the tank for the acidic aqueous solution so as to maintain a constant temperature. The supply amount of the acidic aqueous solution is set according to the cooling rate of the alloy plate A, but is preferably set to 1000 L / h or more in order to ensure the cleaning effect.

  The cooling rate of the alloy plate A in the cooling zone 5 is preferably 5 ° C./s or more, and more preferably 30 ° C./s or more. Further, the temperature after cooling of the alloy plate A is preferably 200 ° C. or less, and more preferably 100 ° C. or less. By setting the cooling rate and the cooling temperature of the alloy plate A in the cooling zone 5 within such ranges, the mechanical properties of the alloy plate A can be sufficiently improved. In addition, the cooling rate and the cooling temperature in the cooling zone 5 can be controlled by increasing or decreasing the supply amount of the cooling medium brought into contact with the alloy plate A and the temperature of the cooling medium.

  In addition, the specific structure of the cooling zone 5 uses the same thing as a general continuous processing apparatus. However, it goes without saying that pipes for introducing or discharging acidic aqueous solutions and nozzles for spraying acidic aqueous solutions need to use acid-resistant ones, for example, particularly excellent in acid resistance among stainless steels. Can be used. Moreover, the vapor | steam and gas which generate | occur | produce when an acidic aqueous solution is made to contact the hot alloy plate A are removed using a conventionally well-known filter apparatus etc.

  The washing zone 6 is for washing and removing the acidic aqueous solution remaining on the surface of the alloy plate A after cooling and washing. The medium used for washing in the washing zone 6 is water, and examples of the washing method include a method of washing by spraying water on both surfaces of the alloy plate A. Moreover, in the washing zone 6, moisture remaining on the surface of the alloy plate A after washing is removed by drying with hot air or the like.

  The recoiler (winding device) 7 is a device for winding the conveyed alloy plate A into a coil shape. The recoiler 7 is disposed most downstream in the continuous processing apparatus 10. The recoiler 7 includes a mandrel (not shown) for supporting the coiled alloy plate A and a winding means (not shown) for winding the alloy plate A, and winds the alloy plate A.

  In addition, the continuous processing apparatus 10 which concerns on embodiment is good also as a structure which further provides straightening apparatuses, such as a roller leveler and a tension leveler, and improves the planarity and quality of the alloy plate A further. Depending on the composition of the alloy plate A, a heating device for heating the cooled and washed alloy plate A to 50 to 150 ° C. is disposed downstream of the cooling zone 5, and the heated alloy plate A is wound by the recoiler 7. It is good also as a structure to take. When the alloy plate A is a 6000 series aluminum alloy which is a heat treatment type alloy, its mechanical properties can be further improved by winding the alloy plate A in a high temperature state.

  As described above, according to the continuous processing apparatus 10 according to the embodiment, the equipment used in the existing continuous annealing line is used as it is, and the alloy plate A after the heat treatment is simultaneously cooled and cleaned in parallel. be able to. Therefore, it is possible to improve the properties of the alloy plate A, such as formability, bake hardness, and degreasing properties, without a new capital investment and an increase in the size of the continuous processing apparatus, and with fewer steps than before.

  Moreover, according to the continuous processing apparatus 10 which concerns on embodiment, since acidic aqueous solution is made to contact the hot alloy plate A immediately after heat processing as a cooling medium, surface cleaning can be performed at temperature higher than before. Therefore, the reaction of the acidic aqueous solution with respect to the oxide film on the surface of the alloy plate A is further promoted, and the acid concentration of the acidic aqueous solution used for cleaning the surface of the alloy plate A can be lowered than before. That is, it is possible to reduce the cost of the medicine and the influence on the environment as compared with the conventional case.

(Continuous processing method)
Next, a continuous processing method of the alloy plate A using the continuous processing apparatus 10 according to the embodiment will be described with reference to FIG.
The continuous processing method of the alloy plate A using the continuous processing apparatus 10 can be mainly divided into a preliminary cleaning process, a heating process, and a cooling process.

  The pre-cleaning step is a step of conveying the alloy sheet A cold-rolled to a desired product plate thickness into the pre-cleaning apparatus 2 and pre-cleaning both surfaces thereof. By passing through this preliminary cleaning process, cold rolling oil, dust, dust and the like adhering to the surface of the alloy plate A are removed, and a state suitable for the subsequent heating / cooling process is obtained.

  The heating process is a process in which the pre-cleaned alloy plate A is conveyed into the heating zone 4 and heated. By passing through this heating step, the alloy plate A can be subjected to a solution treatment or an annealing treatment.

  The cooling step is a step of transporting the heated aluminum alloy plate A into the cooling zone 5 and cooling it. By passing through this cooling step, when the heating step is a solution treatment, the alloy plate A is quenched.

  In this cooling process, an acidic aqueous solution is used as a cooling medium, and the surface of the alloy plate A is cleaned simultaneously with cooling. In this way, the surface of the alloy plate A is simultaneously cleaned in the cooling step, so that the formability of the alloy plate A can be reduced without new capital investment and increase in the size of the continuous processing apparatus and with fewer steps than before. And properties such as bake hardness and degreasing properties can be improved.

  Moreover, since the acidic aqueous solution is brought into contact with the high-temperature alloy plate A immediately after the heat treatment as a cooling medium, the surface can be cleaned at a temperature higher than that in the past. Therefore, the reaction of the acidic aqueous solution with respect to the oxide film on the surface of the alloy plate A is further promoted, and the acid concentration of the acidic aqueous solution used for cleaning the surface of the alloy plate A can be lowered than before. That is, it is possible to reduce the cost of the medicine and the influence on the environment as compared with the conventional case.

(Operation of continuous processing equipment)
Next, the operation of the continuous processing apparatus 10 according to this embodiment will be described with a specific example with reference to FIG.

  First, when the uncoiler 1 feeds the coiled alloy plate A to the downstream side of the continuous processing device 10, the preliminary cleaning device 2 cleans both sides of the alloy plate A that has been conveyed, and the surface of the alloy plate A is cold. Remove rolling oil, dust, dust, etc. Then, the upstream accumulator 3a conveys the cleaned alloy plate A to the downstream heating zone 4 while adjusting the feed amount and tension of the cleaned alloy plate A.

  The heating zone 4 rapidly heats both sides of the conveyed alloy plate A to 500 to 550 ° C. with hot air. The cooling zone 5 is rapidly cooled to 200 ° C. at a cooling rate of 5 ° C./s or more by spraying an acidic aqueous solution on both surfaces of the rapidly heated alloy plate A. At the same time, the oxide film on the surface of the alloy plate A is removed by reacting with the acidic aqueous solution.

  Next, the rinsing belt 6 sprays water on both surfaces of the rapidly cooled alloy plate A to remove the acid component remaining on the surface of the alloy plate A, and dries the moisture on the surface of the alloy plate A with hot air. Remove. And the downstream accumulator 3b is conveyed to the recoiler 7, adjusting the feed amount and tension | tensile_strength of the wash | cleaned alloy plate A, and winds the alloy plate A in which the recoiler 7 was conveyed in coil shape.

  Next, examples in which the effects of the present invention have been confirmed will be described with reference to Table 1. In this example, the cleanliness of the aluminum alloy plate when the continuous processing apparatus is actually operated and the type and concentration of the cooling medium used in the cooling zone is changed is evaluated. In addition, this invention is not limited only to this Example.

The processing condition column in Table 1 will be described below.
(Alloy, treated plate temperature)
In this example, two types, a 6022 aluminum alloy plate (hereinafter referred to as 6022 alloy plate) and a 5182 aluminum alloy plate (hereinafter referred to as 5182 alloy plate) having a thickness of 1 mm, were used. The 6022 alloy plate and the 5182 alloy plate were conveyed to a heating zone, rapidly heated so that the plate temperatures were 540 ° C. and 450 ° C., respectively, and then held for 30 seconds. Then, the held 6022 alloy plate and 5182 alloy plate were transported to a cooling zone, rapidly cooled at 30 ° C./s so as to be 100 ° C., washed with pure water, and dried to prepare a sample.

(Cooling medium type and concentration)
As the cooling medium, five types of sulfuric acid aqueous solution, phosphoric acid aqueous solution, mixed acidic aqueous solution of sulfuric acid aqueous solution and phosphoric acid aqueous solution, nitric acid aqueous solution, and water were used. Moreover, the density | concentration with respect to the water of the acid component in acidic aqueous solution and mixed acidic aqueous solution was made into the range of 0.005-10 mass%. In Table 1, “sulfuric acid” indicates a sulfuric acid aqueous solution, “phosphoric acid” indicates a phosphoric acid aqueous solution, and “nitric acid” indicates a nitric acid aqueous solution.

Hereinafter, the measurement result column in Table 1 will be described.
(Oxide film thickness)
The oxide film thickness of the sample was measured by surface analysis of glow discharge optical emission spectrometry (hereinafter referred to as GD-OES). Further, the thickness at which the maximum value of the oxygen concentration was reduced to ½ based on the results of GD-OES depth direction composition analysis was defined as the oxide film thickness. Here, the oxide film thickness indicates that the smaller the value (the thinner the oxide film), the higher the cleaning degree in the cooling zone.

(Mg / Al ratio)
The Mg / Al ratio was also measured by GD-OES surface analysis. The Mg / Al ratio was obtained by measuring the Mg concentration and Al concentration of the outermost layer portion of each alloy plate and calculating the ratio. The oxide film on the surface of the aluminum alloy plate is also formed by oxidation of Mg on the plate surface, and it is known that the degreasing property is inferior when the Mg concentration on the surface is high. In this example, the Mg / Al ratio was also calculated as an index of the degree of cleaning. Here, the Mg / Al ratio indicates that the smaller the value (the lower the Mg concentration ratio), the higher the cleaning degree in the cooling zone.

(Area wetted after degreasing)
The water wetting area after degreasing is measured by the fact that the thicker the oxide film on the surface of the aluminum plate and the higher the Mg / Al ratio, that is, the lower the degree of cleaning in the cooling zone, the less rust-preventing oil will be degreased ( Focusing on the property that rust oil remains), the actual wetted area was measured as an index indicating the degree of cleaning. Further, if the rust preventive oil remains on the aluminum alloy plate, it becomes difficult for the chemical conversion treatment film to adhere during chemical conversion treatment, resulting in chemical conversion treatment unevenness, and the coating appearance and corrosion resistance are reduced. Therefore, it can be said that the greater the wetted area after degreasing, the better the coating appearance and the corrosion resistance.

The measurement of the wetted area after degreasing was performed according to the following procedure.
First, the surface of each sample was lubricated with a commercially available rust preventive lubricating oil “RP-75N manufactured by Yuken Kogyo Co., Ltd.” and then left for 7 days in an environment of temperature 40 ° C. and humidity 90%. . Next, these samples were immersed for 2 minutes at 40 ° C. in a deterioration solution (pH 11, 3,000 ppm of rust preventive oil added) of a commercially available alkaline degreasing agent “FC-L4460 manufactured by Nihon Parkerizing Co., Ltd.” maintained at 60 ° C. And washed with water for 30 seconds. Then, the wetted area after standing for 30 seconds after washing with water was visually confirmed and measured. In this example, a product having a wetted area after degreasing of 10% or more was regarded as acceptable.

  Here, the sample Nos. 1-26 is the Example which concerns on this invention which performed cooling and pickling in parallel using the acidic aqueous solution as a cooling medium in the cooling zone of a continuous processing apparatus.

  Sample No. Nos. 27 to 30 are comparative examples according to the related art in which only cooling is performed using water as a cooling medium in the cooling zone of the continuous processing apparatus, and then pickling with an aqueous sulfuric acid solution is performed separately. In addition, the density | concentration of the sulfuric acid aqueous solution used here is the same 1.5 mass% as the samples 7 and 8 which concern on an Example. Therefore, by referring to the measurement result of this sample, it is possible to compare the surface state of the aluminum alloy plate when pickling and cooling are performed simultaneously and when pickling and cooling are performed separately.

  Sample No. Reference numerals 31 and 32 are reference examples related to the prior art in which cooling is performed using water as a cooling medium only in the cooling zone of the continuous processing apparatus, and then pickling with an acidic aqueous solution. In addition, the density | concentration of the sulfuric acid aqueous solution used here is 10 mass% which is the density | concentration of the sulfuric acid aqueous solution used by the conventional pickling. Therefore, by referring to the measurement result of this sample, it can be confirmed how much the concentration of the sulfuric acid aqueous solution can be reduced by performing pickling and cooling simultaneously in parallel.

  As shown in Table 1, sample No. Since No. 1-26 was pickling in parallel with cooling, the water-wetting area after degreasing was all 10% or more. In particular, sample no. 1, 2, 7, 8, 13, 14, 19, 20 are sample Nos. According to Reference Examples. Although the sulfuric acid aqueous solution having a concentration much lower than that of 31 and 32 was used, the oxide film thickness and the Mg / Al ratio were measured according to Sample No. 31 or 32 or less. Therefore, it was confirmed that by performing the pickling in parallel with the cooling, a cleaning degree equal to or higher than that can be achieved even with an acidic aqueous solution having a lower concentration than that in the separate pickling.

  On the other hand, sample no. Since Nos. 27 to 30 were cooled only with water and were not pickled, the wetted areas after degreasing were all 10% or less. In addition, Sample No. Nos. 31 and 32 had a water wetted area after degreasing of 10% or more, but the concentration of the acidic aqueous solution was high and the cost of the drug was high. Moreover, in the comparative example and the reference example, since the pickling facility is separately provided, there arises a problem that securing of installation space and a large installation cost are necessary.

1 Uncoiler (Feeding device)
2 Preliminary cleaning device 3 Accumulator 3a Upstream accumulator 3b Downstream accumulator 4 Heating zone 5 Cooling zone 6 Flushing zone 7 Recoiler (winding device)
10 Continuous processing equipment (continuous annealing equipment)
A Aluminum alloy plate (alloy plate)

Claims (4)

A continuous processing apparatus for continuously heating and cooling an aluminum alloy plate rolled to a desired plate thickness, the heating zone heating the aluminum alloy plate, and cooling the aluminum alloy plate heated in the heating zone A cooling zone, and
The cooling zone uses an acidic aqueous solution as a cooling medium, and simultaneously performs cooling of the aluminum alloy plate and surface cleaning for improving the degreasing property of the surface of the aluminum alloy plate with the acidic aqueous solution. Board continuous processing equipment. The acidic aqueous solution is any one of a sulfuric acid aqueous solution, a phosphoric acid aqueous solution, or a mixture thereof, and an acid concentration thereof is in a range of 0.005 to 3.000% by mass. The continuous processing apparatus of the aluminum alloy plate of Claim 1 . A continuous treatment method for continuously heating and cooling an aluminum alloy plate rolled to a desired plate thickness, wherein the aluminum alloy plate is conveyed into a heating zone, and the aluminum alloy plate is heated, and heating A subsequent cooling step of conveying the aluminum alloy plate afterwards into a cooling zone and cooling the aluminum alloy plate,
The cooling step uses an acidic aqueous solution as a cooling medium, and simultaneously performs cooling of the aluminum alloy plate and surface cleaning for improving the degreasing property of the aluminum alloy plate surface with the acidic aqueous solution. Continuous processing method for plates. The acidic aqueous solution is any one of a sulfuric acid aqueous solution, a phosphoric acid aqueous solution, or a mixture thereof, and an acid concentration thereof is in a range of 0.005 to 3.000% by mass. The continuous processing method of the aluminum alloy plate of Claim 3 .

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