JP6402650B2 - Aluminum clad steel strip and manufacturing method thereof - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an aluminum clad steel strip and a method for producing the same, specifically, surface smoothness and molding that are used as a casing, an exterior material, a reflector, or the like through molding such as bending, shearing, or deep drawing. The present invention relates to an aluminum clad steel strip suitably used as a material for a foil product excellent in workability and a method for producing the same.

  Aluminum clad steel foil has a specular reflectivity, weather resistance, and chemical resistance that aluminum foil has, but in order to compensate for its strength deficiency, a highly economical steel sheet is used as its inner layer material. The foil product is expected to be used in various forms and applications such as various casings, electronic device members, and reflectors. This aluminum clad steel foil is produced by further cold-rolling and thinning an aluminum clad steel strip that has been clad and bonded in advance.

  In Patent Document 1, an aluminized steel sheet obtained by hot-plating aluminum or an aluminum alloy on a steel sheet is heated to 100 to 550 ° C., and aluminum or aluminum alloy sheets at room temperature are stacked to perform a rolling process with a reduction rate of 10 to 40%. A method of manufacturing an aluminum clad steel strip by press bonding is disclosed.

  In Patent Document 2, an aluminum plate or an aluminum alloy plate is superposed on an aluminum coated steel plate obtained by evaporating or electroplating aluminum or an aluminum alloy on the surface of the steel plate, and at least the aluminum coated steel plate is heated to a temperature of 200 to 500 ° C. and rolled. Thus, a method for producing an aluminum clad steel plate is disclosed.

  However, in the methods disclosed in Patent Documents 1 and 2, when the surface of the aluminum-plated steel sheet heated at the time of rolling and activated at a high temperature comes into contact with the rolling roll, aluminum adheres to the rolling roll, and particularly the coil. When performing long-time joining rolling, the surface properties cannot be kept smooth.

  In this way, when a foil product is manufactured by re-rolling using an aluminum clad steel strip that has been hot-rolled or hot-bonded and the surface smoothness of which has been impaired, fine roughness on the surface of the manufactured foil product. Remains, and there is a problem that the appearance is impaired or the desired specular reflectance cannot be obtained.

  In Patent Documents 3 and 4, steel sheets, plated steel sheets, and aluminum coils, which are joining materials, are surface-treated in a vacuum chamber and then cold rolled using a rolling machine installed in the vacuum chamber. Thus, a method for producing an aluminum clad steel sheet is disclosed.

Japanese Examined Patent Publication No. 56-52679 Japanese Patent No. 2761963 International Publication No. 00/039861 Pamphlet Japanese Patent Laid-Open No. 4-91872

  In the rolling mill installed in the vacuum chamber disclosed in Patent Documents 3 and 4, the rolling lubricant cannot be used, and the surface of the material to be rolled is chemically activated. Cannot be prevented, and the surface properties of the manufactured aluminum clad steel strip cannot be kept smooth.

  As described above, when an aluminum clad steel strip that has been bonded in a vacuum chamber and whose surface smoothness has been impaired is produced by rolling again using this as a raw material, a fine rough surface is formed on the surface of the produced foil product. Will remain, impairing the appearance, and failing to obtain the desired specular reflectance.

  In order to solve this problem, it may be considered that the joining material may be cold rolled (at room temperature) and heated using a suitable rolling lubricant without heating the bonding material. However, sufficient joining strength cannot be obtained with such an aluminum clad steel sheet obtained by cold rolling. For this reason, in the rolling process that is subsequently performed to obtain a foil product having a desired bonding strength, interfacial peeling occurs, or when the obtained foil product is subjected to processing such as bending, shearing or deep drawing. There is a problem of causing interface peeling.

  The present invention has been made in view of such problems of the prior art, and has been difficult to achieve with conventional aluminum clad steel strips, such as high surface smoothness, bending, shearing, and deep drawing. An object of the present invention is to provide an aluminum clad steel strip that is suitably used as a material for a foil product that has joint strength that can withstand forming processing, that is, a foil product that is excellent in surface smoothness and formability, and a method for producing the same. .

  In producing an aluminum clad steel strip in which plain steel and aluminum are bonded and rolled, the present inventors have carried out cold bonded rolling using a rolling lubricant in order to keep the surface state as bonded rolled smooth. As a result of diligently investigating a method for obtaining sufficient bonding strength by the above, the surface of the steel strip is preliminarily plated with an aluminum alloy to obtain an aluminum-plated steel strip. In the case of cold rolling under bonding, although the bonding strength immediately after bonding is small, the interface between the aluminum plating layer and aluminum is sufficiently in metal contact, so it is excellent by performing heat treatment under appropriate conditions. Aluminum with excellent surface smoothness and high bonding strength that can withstand molding such as bending, shearing or deep drawing. It was found that obtained by Rudd steel strip, and completed the present invention by overlapping a further study. The present invention is listed below.

  (1) Two-layer or three-layer aluminum clad steel strip in which an industrial pure aluminum coil is cold-bonded and rolled on one side or both sides of an aluminum-plated steel strip, and pure aluminum disposed on at least one side thereof The surface roughness of the layer is 0.3 μm or less in terms of the arithmetic average roughness Ra specified in JIS B 0601 (2001), and the peel strength when peeling the bonding interface of the two or three layers is 0 per unit width. An aluminum clad steel strip used as a material for a foil product excellent in surface smoothness, characterized by having a width of 5 N / mm or more.

(2) By joining and rolling the aluminum plated steel strip and the industrial pure aluminum coil by a cold rolling method using the aluminum plated steel strip and the industrial pure aluminum coil as a raw material, A method of manufacturing comprising:
While spraying or applying a rolling lubricant to the surface of the work roll during the joint rolling, the kinematic viscosity ν (mm ² / sec) of the oil contained in the rolling lubricant, the rolling speed V ( m / min), and a value T = ν × V × (1-r) calculated by a rolling ratio r (%) of the whole of the raw material is set to 20 to 2000, The rolling rate of each material is over 10%, the rolling rate of the entire material is set to 10 to 65%, and heat treatment is performed at 250 ° C. to 450 ° C. for 1 second or more following the joining rolling. A method for producing a featured aluminum clad steel strip.

  In this case, the arithmetic average roughness Ra specified in JIS B 0601 (2001) of the work roll used in the joining rolling may be 0.3 μm or less and the maximum height Rz may be 2.5 μm or less. desirable.

  According to the present invention, a foil product that combines high surface smoothness, which is difficult to realize with conventional aluminum clad steel strips, and joint strength that can withstand forming processing such as bending, shearing and deep drawing, that is, surface smoothness. An aluminum clad steel strip that can be suitably used as a material for a foil product excellent in moldability can be provided.

FIG. 1 is a graph showing the influence of the heat treatment temperature after joining on the joining strength of an aluminum clad steel sheet produced by cold joining rolling.

1. Aluminum clad steel sheet according to the present invention When producing an aluminum clad steel strip by joining ordinary steel and aluminum directly by joint rolling, generally, individual rolling of individual constituent materials at a heating temperature of room temperature to 500 ° C. It is necessary to perform joint rolling under the conditions that all the rates are 10% or more. Further, in order to obtain a joining strength that can withstand a molding process such as bending, shearing, or deep drawing, it is necessary to heat the constituent material to a temperature of 200 to 500 ° C. prior to joining.

  However, when trying to produce an aluminum clad steel strip by such hot or hot joining rolling, the surface of aluminum activated by heating is in direct contact with the rolling roll, so that both of them are likely to adhere, Time-consuming coil rolling cannot prevent aluminum from adhering to the rolling roll, and the surface properties of the obtained aluminum clad steel strip cannot be kept smooth.

  In order to solve this problem, it is effective to join plain steel and aluminum by cold joining and rolling using a rolling lubricant, but solid plain steel and aluminum are joined by cold joining and rolling. In order to join stably, a rolling rate as high as about 70% is required as the total rolling rate of all the constituent materials. In such a large rolling reduction, the rolling load increases, so the material being joined and rolled. The stress applied to the contact surface between the surface and the rolling roll is increased, and adhesion of aluminum to the rolling roll cannot be prevented.

  On the other hand, the surface to be joined by applying a plating treatment made of an aluminum alloy in advance to the surface of ordinary steel is made an aluminum alloy plating and an interface made of aluminum, so that stable rolling even at a small rolling rate. Thus, adhesion of aluminum to the rolling roll can be prevented.

  Even if the interface to be joined in this way is an interface made of aluminum alloy plating and aluminum, sufficient joining strength cannot be obtained at the joining interface of the aluminum clad steel strip that has been cold-rolled, and bending, shearing or When forming such as deep drawing, there is a risk of causing interface peeling.

  On the other hand, the joining strength at the joining interface can be increased by performing heat treatment under suitable conditions for the aluminum clad steel strip that has been cold-rolled under appropriate conditions. This is because the thermal energy necessary for the interface to be integrated with the rearrangement of crystal orientation, even though the cold bonded and rolled interface is sufficiently in metal contact. This is considered to be because sufficient bonding strength cannot be obtained due to the shortage of bonding, whereas the bonding interface is integrated by performing heat treatment under appropriate conditions. In other words, the bonding strength of the interface bonded under conditions such that the interface is in uniform metal contact during cold bonding rolling can be increased by subsequently performing an appropriate heat treatment.

  FIG. 1 shows an aluminum clad steel strip obtained by cold rolling an aluminum-plated steel strip and an aluminum coil in accordance with the above method, and the heat treatment temperature after joining is 7 levels in the range of 20 ° C. or more and 500 ° C. or less. The effect of the heat treatment on the bonding strength by the peel test performed on the aluminum clad steel strip obtained by performing the heat treatment with a change in the graph is shown in a graph.

  The bonding strength was defined as the load cell load when the interface was forcibly peeled from one end of a strip sample having a width of 10 mm and a length of 120 mm cut out as a sample, and each peeled end was chucked and peeled off by a tensile tester. .

  As shown in the graph of FIG. 1, the bonding strength is remarkably increased in the heat treatment temperature range of 250 ° C. or higher and 450 ° C. or lower.

  Moreover, using the sample used for the measurement of the bonding strength, a strip sample having a width of 6 mm and a length of 100 mm was cut out and subjected to a twist-back test and a 90-degree repeated bending test to evaluate the moldability.

  In the twist-back test, a sample having a length of 100 mm was twisted twice by 10 mm at both ends, and the pass / fail was judged by the presence or absence of interfacial delamination after the operation of returning twice. Further, in the 90-degree repeated bending test, the pass / fail was judged by the presence / absence of interfacial peeling after bending the free end 90 degrees by one reciprocation left and right with one end 50 mm of a sample having a length of 100 mm as a grip portion. Table 1 summarizes the results of the moldability evaluation test.

  As shown in Table 1, in both the untwisting test and the 90-degree repeated bending test, good moldability was obtained when the heat treatment temperature was in the range of 250 ° C to 450 ° C. It can be seen that an aluminum clad steel strip having excellent formability can be obtained in the range where the bonding strength (peel strength) by the peel test is 0.5 N / mm width or more.

  Furthermore, it can be seen from the results shown in FIG. 1 and Table 1 that the joint strength having a joint strength of 0.5 N / mm width or more is equivalent to the pass / fail judgment criteria of the untwisting test and the 90 ° repeated bending test. As described above, the bonding strength is measured by forcibly peeling the interface from one end of the cut strip sample and then chucking and peeling each end to a tensile tester. When the thickness is less than 5 mm, the base material may be broken in the work of peeling off, resulting in a case where the bonding strength cannot be measured. Therefore, in the case where the thickness of one end peeled off is less than 0.5 mm and when evaluating the bondability of a clad material rolled with foil, the bondability should be evaluated by a twist back test and a 90 ° repeated bending test. Can do.

  As described above, aluminum-plated steel that has been pre-plated with an aluminum alloy as a technique for realizing clad bonding by the cold rolling method, which is necessary to obtain an aluminum-clad steel strip used as a material for foil products with excellent surface smoothness. The strip and the aluminum coil are joined together by a cold rolling method using a rolling lubricant under the condition that each rolling ratio exceeds 10%, and the obtained clad coil is further heated to 250 ° C. or higher and 450 ° C. or lower for 1 second. It is effective to perform the heat treatment to be held as described above.

  A foil product obtained by performing cold rolling at a rolling rate of 50% or more using an aluminum clad steel strip that has been cold rolled as described above as a raw material is Gs (60 °) described in JIS Z 8741. The specular glossiness exceeds 800, and the surface quality on appearance is good.

  Here, when the surface of the aluminum clad steel strip immediately after being joined by the hot rolling method or the vacuum rolling method exceeds 0.3 μm in the arithmetic average roughness Ra specified in JIS B 0601, the Gs ( 60 °) Since the specular gloss is less than 800, and the appearance quality is judged to have a problem such as cloudiness failure on the surface, the arithmetic defined in JIS B 0601 is used as an index of a rolled foil material having excellent surface smoothness. It can be used as an index that the average roughness Ra is 0.3 μm or less.

2. Manufacturing method of aluminum clad steel strip according to the present invention An aluminum clad steel strip according to the present invention is manufactured by joining and rolling both materials by a cold rolling method using an aluminum plated steel strip and an industrial pure aluminum coil as raw materials. Is done. That is, when joining and rolling an industrial pure aluminum coil on one side of an aluminum plated steel strip, it becomes a two-layer aluminum clad steel strip, and when joining and rolling an industrial pure aluminum coil on both sides of an aluminum plated steel strip It becomes a three-layer aluminum clad steel strip.

  The aluminum-plated steel strip used as a raw material can be one produced by a normal hot dipping or electroplating method, but an aluminum alloy containing 5 mass% or more and 15 mass% or less of Si on the surface of ordinary steel. Those that are hot-dip plated or those obtained by electroplating pure aluminum on the surface of plain steel can be used.

  The thickness of the plating layer is not particularly limited, and is exemplified to be 5 μm or more and 50 μm or less.

  Moreover, the industrial pure aluminum prescribed | regulated as a 1000 series alloy by JISH4000 is used for the aluminum coil joined with an aluminum plating steel strip. This makes it possible to maintain good clad bonding by using pure aluminum with few impurities, and to prevent the alloy elements in the aluminum layer from forming a different phase and being exposed to the surface, thereby impairing surface smoothness. It is to do.

  For the coil pretreatment of these materials used for joint rolling, it is only necessary to remove oil and dirt on the surface using a normal cleaning method, but if necessary, the surface is dissolved or brushed. May be.

  For the joining rolling, a normal clad joining rolling mill can be used. That is, this is a coil cold rolling mill in which a plurality of unwinding reels are arranged on the entry side of a two-stage to six-stage serial rolling mill and a rolling lubricant supply device is provided in the vicinity of the exit side of the rolling roll.

  In order to keep the surface immediately after cold-bonding rolling smooth, the surface roughness of the work roll used is 0.3 μm or less in terms of arithmetic average roughness Ra defined in JIS B 0601, and the maximum height. Rz is preferably 2.5 μm or less. This is because when the arithmetic average roughness Ra exceeds 0.3 μm, or the maximum height Rz exceeds 2.5 μm, the local contact stress increases at the tip of the roughness. This is because there is a possibility that the aluminum adheres to the rolling roll and the smoothness of the surface of the clad coil after the joint rolling cannot be maintained due to the rolling for a long time due to the direct contact.

The rolling lubricant used for joint rolling can be either mineral type or emulsion type. However, in order to keep the surface smooth immediately after cold joining rolling, the kinematic viscosity of mineral oil or emulsion lubricant base is used. A value T = ν × calculated from the kinematic viscosity ν (mm ² / sec) of the oil, the rolling speed V (m / min) at the time of joint rolling, and the rolling ratio r (%) of the entire coil as the material. V × (1-r) is 20 or more and 2000 or less.

  This value T is a parameter related to the oil film thickness that hinders direct contact between the material to be rolled and the rolling roll. When the value T is less than 20, the oil film thickness becomes too thin and the material to be rolled and the rolling roll Direct contact cannot be inhibited, and aluminum is adhered to the rolling roll through long-time rolling, so that the smoothness of the surface of the clad coil after joint rolling cannot be maintained. On the other hand, when the value T exceeds 2000, the oil film becomes too thick to transfer the smooth surface of the rolling roll to the material to be rolled, and the surface of aluminum as the material to be rolled passes through the oil film. Therefore, unintentional irregularities occur due to free deformation, and the smoothness of the surface of the clad coil after the joint rolling cannot be maintained.

  Joining rolling can be achieved even by rolling only one pass with overlapping materials, but the rolling rate at that time is higher than 10% for each material, and the entire coil as a material is integrated. It is desirable that the rate be 10% to 65%. If the rolling rate of any of the individual materials is less than 10%, the effect of bringing the joint surface into uniform metal contact with the expansion of the material surface cannot be obtained, and it is sufficient even after the subsequent heat treatment. Bond strength cannot be obtained. In addition, if the rolling ratio of the entire coil as a material exceeds 65%, the stress acting between the material coil and the rolling roll during joint rolling becomes too large, so the aluminum material and the rolling roll are in direct contact with each other. As a result, the direct contact between the material to be rolled and the rolling roll cannot be obstructed, and the aluminum adheres to the rolling roll through long-time rolling, and the smoothness of the surface of the clad coil after joint rolling is reduced. I can't keep it.

  As described above, a clad coil bonded and rolled under appropriate conditions cannot be obtained with sufficient bonding strength even though the bonding interface is in uniform metal contact. It is desirable to perform a heat treatment for holding for 1 second or longer. This is because by applying heat treatment to the clad interface sufficiently in metal contact by cold rolling joining, the integration of the interface accompanied by rearrangement of crystal orientation proceeds and the joining strength increases. it is conceivable that.

  If the temperature of the heat treatment is lower than 250 ° C. or if the holding time is shorter than 1 second, the thermal energy given to the cladding interface is insufficient, so the integration of the interface with the rearrangement of crystal orientation does not proceed, Bonding strength does not increase. On the other hand, when the heat treatment temperature exceeds 450 ° C., hard and brittle intermetallic compounds such as Fe—Al and Fe—Al—Si are formed at the interface between the normal steel and aluminum as the core material, and the bonding strength at the interface is impaired. There is a possibility.

  Note that the upper limit of the holding time in the heat treatment is not particularly required, but is preferably 24 hours or less from the viewpoint of productivity.

  The method of heat treatment is not particularly limited, and examples thereof include using an electric furnace heating in the atmosphere or an electric furnace heating in an inert gas such as nitrogen or argon. Also, the heat treatment furnace is not particularly limited, and a vertical furnace or a horizontal furnace included in a continuous heat treatment line may be used, or a box furnace that performs batch heat treatment may be used.

  Thus, according to the present invention, it has high surface smoothness, which is difficult to realize with the conventional aluminum clad steel strip, and joint strength that can withstand forming processing such as bending, shearing and deep drawing. An aluminum clad steel strip that is suitably used as a material for a foil product, that is, a foil product excellent in surface smoothness and moldability can be obtained.

The present invention will be described more specifically with reference to examples.
As materials for producing an aluminum clad steel strip, (a) a 0.6 mm thick aluminum plated steel strip obtained by hot-plating Al-10% Si alloy on both sides of ordinary steel, and (b) a thickness of 0.5 mm A1100 pure aluminum coil mass production coil was prepared.

  Using an experimental coil rolling mill, pure aluminum, an aluminum-plated steel strip, and pure aluminum were installed on three unwinding reels arranged on the inlet side, and these three types of materials were placed in the line. A three-layer aluminum clad steel strip clad coil according to the present invention was prepared by superimposing in order and joining and rolling cold.

The work roll used for rolling at this time is a normal forged steel roll having a diameter of 200 mm, and the surface is polished with a # 240 grindstone so that the arithmetic average roughness Ra is 0.12 μm and the maximum height Rz is 1.02 μm. Respectively. Further, as a rolling lubricant, a mineral oil having a kinematic viscosity of 11 mm ² / sec at 40 ° C. and a lubricating oil having a kinematic viscosity of 210 mm ² / sec at 40 ° C. were diluted to 4.0% by mass with distilled water. Two types of emulsion type lubricants were used.
For comparison, using the same 0.6 mm aluminum-plated steel strip and 0.5 mm thick A1100 pure aluminum coil as described above, hot joining rolling at a heating temperature of 200 ° C. and hot joining rolling at 400 ° C. Thus, a clad coil of an aluminum clad steel strip of a comparative example was prepared.

The work roll used for rolling at this time is a forged steel roll having a diameter of 200 mm similar to that used in the above-described cold joining rolling, and the rolling lubricant has a kinematic viscosity at 40 ° C. of 210 mm ² / sec. An emulsion type lubricant in which the lubricating oil was diluted to 4.0% by mass with distilled water was used.

  Furthermore, for comparison, an aluminum clad steel of a comparative example was obtained by performing cold joint rolling in a vacuum chamber using a 0.6 mm thick normal steel strip and a 0.5 mm thick A1100 pure aluminum coil. A clad coil was made.

  As a rolling roll at this time, a forged steel roll having a diameter of 100 mm was used, and the surface was polished with a # 240 grindstone to prepare an arithmetic average roughness Ra of 0.10 μm and a maximum height Rz of 0.95 μm. No rolling lubricant is used.

  Samples of an appropriate size were cut out from the clad coils of the present invention example and the comparative example thus obtained, and the surface smoothness was evaluated using the arithmetic average roughness Ra specified in JIS B 0601.

  In addition, the sample cut out from the obtained clad coil was subjected to heat treatment at various temperatures using a laboratory electric furnace, and then a strip sample having a width of 6 mm and a length of 100 mm was cut out from the obtained sample. A twist-back test and a 90-degree repeated bending test were performed to evaluate the moldability.

  In the twist-back test, a sample having a length of 100 mm was twisted twice by 10 mm at both ends, and the pass / fail was judged by the presence or absence of interfacial delamination after the operation of returning twice. Further, in the 90-degree repeated bending test, the pass / fail was judged by the presence / absence of interfacial peeling after bending the free end 90 degrees by one reciprocation left and right with one end 50 mm of a sample having a length of 100 mm as a grip portion.

Furthermore, the obtained clad coil was cold-rolled again under the condition of a reduction ratio of 50%, thereby obtaining an aluminum clad steel foil. At this time, a mineral oil having a kinematic viscosity of 11 mm ² / sec at 40 ° C. is used as a lubricating oil, a normal forged steel roll having a diameter of 200 mm is used as a work roll for rolling, and the surface is polished with a # 600 grindstone to obtain an arithmetic average The roughness Ra was adjusted to 0.04 μm, and the maximum height Rz was adjusted to 0.35 μm.

  Regarding the obtained aluminum clad foil, the Gs (60 °) specular gloss described in JIS Z 8741 was measured and the appearance was observed to determine pass / fail. In addition, HG-246 by Suga Test Instruments Co., Ltd. was used for the measurement of Gs (60 °) specular gloss.

  Table 2 summarizes the experimental conditions and the evaluation results for each test. In addition, the underline in Table 2 shows that it deviates from the conditions of this invention, or an evaluation result is unsatisfactory.

  Numbers 1 to 8 in Table 2 are all examples of the present invention that satisfy all of the conditions specified in the present invention, and an aluminum clad steel strip having good surface smoothness and moldability was obtained. I understand.

  No. 9 is a comparative example in which the maximum height Rz of the surface of the work roll is 2.64 μm, which exceeds the upper limit of the range of the present invention, and aluminum adheres to the roughness tip of the work roll. The smoothness of the surface was unsatisfactory. Furthermore, the foil product manufactured by re-rolling using this aluminum clad steel strip as a raw material had a Gs (60 °) specular gloss of less than 800 as described in JIS Z 8741, and also had poor haze on the appearance.

  No. 10 is a comparative example in which the T value is 14, which is below the lower limit of the range of the present invention, and since aluminum adhered to the roughness tip of the work roll, the smoothness of the surface of the aluminum clad steel strip was poor. It was. Furthermore, the foil product manufactured by re-rolling using this aluminum clad steel strip as a raw material had a Gs (60 °) specular gloss of less than 800 as described in JIS Z 8741, and also had poor haze on the appearance.

  No. 11 is a comparative example in which the T value is 2268, which exceeds the upper limit of the range of the present invention, and the surface of the aluminum clad was free-deformed to form irregularities, so the smoothness of the surface of the aluminum clad steel strip was poor. It was. Furthermore, the foil product manufactured by re-rolling using this aluminum clad steel strip as a raw material had a Gs (60 °) specular gloss of less than 800 as described in JIS Z 8741, and also had poor haze on the appearance.

  No. 12 is a comparative example in which the rolling rate of the entire material in the joint rolling is 70, which exceeds the upper limit of the range of the present invention, and the rolling load increases and is added to the contact surface between the material surface and the rolling roll during the joint rolling. Since the stress increased and aluminum adhered to the rolling roll, the smoothness of the surface of the aluminum clad steel strip was unsatisfactory. Furthermore, the foil product manufactured by re-rolling using this aluminum clad steel strip as a raw material had a Gs (60 °) specular gloss of less than 800 as described in JIS Z 8741, and also had poor haze on the appearance.

  Nos. 13 and 14 are comparative examples in which the temperature of the heat treatment performed after joining is outside the range defined in the present invention, and since the intended joining strength was not obtained, the interface was used in the untwisting test and 90-degree repeated bending. Peeling occurred.

Furthermore, numbers 14 to 16 are comparative examples joined by warm joining rolling, hot joining rolling, and cold joining rolling in vacuum, respectively, and all of aluminum to the rolling roll during joining rolling. Since the adhesion could not be prevented, the smoothness of the surface of the aluminum clad steel strip was poor. In addition, foil products manufactured by re-rolling using these aluminum clad steel strips as a raw material had a Gs (60 °) specular gloss of less than 800 as described in JIS Z 8741, and also had poor haze on the appearance. .

Claims (2)

  A two-layer or three-layer aluminum clad steel strip in which an industrial pure aluminum coil is cold-rolled on one or both sides of an aluminum-plated steel strip, and the surface of the pure aluminum layer disposed on at least one side thereof The arithmetic mean roughness Ra specified in JIS B 0601 (2001) is 0.3 μm or less, and the peel strength when peeling the bonding interface of the two or three layers is 0.5 N / unit width. An aluminum clad steel strip having a width of mm or more. The aluminum clad steel strip according to claim 1 is manufactured by joining and rolling the aluminum plated steel strip and the industrial pure aluminum coil by a cold rolling method using the aluminum plated steel strip and the industrial pure aluminum coil as a raw material. A method,
While spraying or applying a rolling lubricant to the surface of the work roll during the joint rolling, the kinematic viscosity ν (mm ² / sec) of the oil contained in the rolling lubricant, the rolling speed V ( m / min), and a value T = ν × V × (1-r) calculated by a rolling ratio r (%) of the whole of the raw material is set to 20 to 2000, The rolling rate of each material is over 10%, the rolling rate of the entire material is set to 10 to 65%, and heat treatment is performed at 250 ° C. to 450 ° C. for 1 second or more following the joining rolling. A method for producing a featured aluminum clad steel strip.

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