JP5952948B1 - Aluminum resin composite laminate - Google Patents

Abstract

[PROBLEMS] To improve the formability when producing a three-dimensional molded article by press molding, and to suppress rough skin and cracks including fine irregularities on the surface of the aluminum plate material after molding to obtain good appearance characteristics. Provision of synthetic resin composite laminates. An aluminum synthetic resin composite laminate comprising aluminum plates 3 and 4 laminated on both surfaces of a synthetic resin layer 2 and used for molding a three-dimensional molded product having a convex surface 3 on one side and a concave surface 4 on the other side. 1, the aluminum plate 3 on the convex surface side contains 1.5 to 1.8% by mass of magnesium and 0.01% by mass or less of copper, the balance is made of aluminum and inevitable impurities, and the other aluminum plate 4 contains 0.01 to 0.03% by mass of copper, the balance is made of aluminum and inevitable impurities, and the thickness of the convex aluminum plate 3 is larger than the thickness of the concave aluminum plate 4. A composite laminate 1. [Selection] Figure 1

Description

  The present invention relates to an aluminum resin composite laminate obtained by laminating an aluminum plate and a synthetic resin layer.

  With the recent reduction in weight of vehicles, it has been studied to use aluminum plates for some steel plates of vehicle bodies and vehicle parts. In addition, in order to impart vibration damping properties, sound insulation properties, heat insulation properties, and the like, it has been proposed to provide an aluminum resin composite laminate in which a synthetic resin layer is sandwiched between two aluminum plates.

  Patent Document 1 discloses a laminated plate in which a foamable resin layer is provided between two aluminum alloy plates. The aluminum plate in this case is selected from JIS standard 1000 series, 3000 series, 5000 series, and 6000 series aluminum alloys. The aluminum plate is preferably as thin as possible, and is in the range of 0.05 to 1.0 mm. Further, in order to improve moldability, it is a tempering treatment material selected from O material, H22 material to H24 material, H32 material to H34 material, and T4 material, according to the quality symbol planned in the JISH0001 standard. As the foamable resin, a polyolefin resin is used, and it is described that the thickness of the entire laminated board is 3.4 mm or less.

  Patent Document 2 discloses an example in which the laminated plate described in Patent Document 1 is applied to a light heat ray shielding cover having a three-dimensional shape and excellent heat ray shielding properties such as a heat insulator. As a method for forming the laminated plate, it is described that press forming such as bulging forming, drawing forming, bending forming, or bending processing is possible, and the resin layer is foamed by heating after the forming processing.

  In Patent Document 3, a thermoplastic resin layer and an aluminum material are laminated, and in the surface layer of the aluminum material, a porous aluminum oxide film layer having a thickness of 20 to 500 nm on the surface side and a thickness of 3 to 30 nm on the substrate side. A barrier type aluminum oxide film layer is provided, small pores having a diameter of 25 to 120 nm are formed in the porous aluminum oxide film layer, and the same as the thermoplastic foam resin layer at the joint between the aluminum material and the thermoplastic foam resin layer The non-foamed resin layer of the component is formed on the porous aluminum oxide film layer to a thickness of 1 to 50 μm and from the surface to the depth of 0.5 nm or more toward the inside of the small hole / aluminum material / thermoplastic A composite material of a foamed resin layer is disclosed. It is described that a composite material having excellent adhesion and formability is obtained by adopting such a configuration.

International Publication No. 2010/029955 International Publication No. 2010/029946 JP 2012-25145 A

  By the way, in any composite laminate described in any patent document, it is useful when press-molding into a two-dimensional product or a three-dimensional product having a slight depth. Rough skin and cracks that include fine irregularities on the surface are likely to occur. In particular, in the case of a composite plate used for an outer plate of a vehicle, it is required to have a good surface without rough skin, and further improvement is desired. Also, as in Patent Document 1 or 2, there is an attempt to ensure moldability by foaming the core resin after molding. However, the resin foam after molding tends to cause changes in the dimensions of the laminate and distortion, and other parts. There is a high risk of becoming an obstacle during assembly.

  The present invention has been made in view of the above circumstances, and further improves the moldability when producing a three-dimensional molded product by press molding, and provides an aluminum synthetic resin composite laminate that provides good appearance characteristics after molding. The purpose is to provide.

  The aluminum resin composite laminate of the present invention comprises an aluminum plate laminated on both sides of a synthetic resin layer, and is used for molding a three-dimensional molded product in which one side is convex and the other side is concave. The aluminum plate material on the convex surface side contains magnesium in an amount of 1.5% to 1.8% by mass and copper in an amount of 0.01% by mass with the balance being aluminum and inevitable impurities, The aluminum plate material contains 0.01% by mass or more and 0.03% by mass or less of copper, the balance is made of aluminum and inevitable impurities, and the thickness of the aluminum plate material on the convex surface side is greater than the thickness of the other aluminum plate material. Is also formed large.

  In this aluminum resin composite laminate, the aluminum plate material disposed on both sides of the synthetic resin layer is different in thickness from the components, and the aluminum plate material on the convex surface side is the other (side opposite the convex surface) aluminum plate material Compared to, strength is high and thickness is large. For this reason, rigidity also becomes large. In other words, the aluminum plate on the other side (opposite side of the convex surface) is easier to deform than the aluminum plate on the side of the convex surface. For this reason, when three-dimensional forming is performed, an aluminum plate having high strength and rigidity is placed on the convex surface (usually the outer surface), and the other easily deformable aluminum plate is placed on the opposite side (inner surface) of the convex surface. By arranging and molding, a three-dimensional molded product having a smooth outer surface and excellent design can be obtained while ensuring good moldability.

In this case, the aluminum plate material on the convex surface side has insufficient strength and rigidity when the magnesium content is less than 1.5% by mass, and when it exceeds 1.8% by mass, three-dimensional forming becomes difficult. On the other hand, if the copper content exceeds 0.01% by mass, the variation in strength increases.
On the other hand, the other aluminum plate material has insufficient strength and rigidity when the copper content is less than 0.01% by mass, and molding defects such as cracks tend to occur when the content exceeds 0.03% by mass.

  In the aluminum resin composite laminate of the present invention, the aluminum plate on the convex surface side has a tensile strength of 150 MPa to 170 MPa, a proof stress of 55 MPa to 75 MPa, an elongation of 15% or more, and the other aluminum plate is The tensile strength is preferably 60 MPa or more and 80 MPa or less, the proof stress is 50 MPa or more and 70 MPa or less, and the elongation is 20% or more.

  By using such a composite laminated plate in which aluminum plate materials are combined, it is possible to reliably prevent molding defects such as rough skin and cracks and to obtain a good three-dimensional molded product.

  In the aluminum resin composite laminate of the present invention, the aluminum plate on the convex surface side has a thickness of 0.2 mm to 0.5 mm, and the other aluminum plate has a thickness of 0.1 mm to 0.00 mm. The thickness of the synthetic resin layer is preferably 1 mm or more and 10 mm or less.

  By setting the thickness as described above, a three-dimensional molded product can be manufactured in a wide range such as a vehicle body or a vehicle part.

  In the aluminum resin composite laminate of the present invention, the synthetic resin layer may be made of a synthetic resin having a melting point of 100 ° C. or higher.

  In order to obtain a product with a complicated three-dimensional shape, warm molding may be performed by heating the material and mold to 100 ° C or higher, and in some cases to about 140 ° C. The synthetic resin layer is melted by the heat at that time. Thus, it can be prevented from flowing out between the aluminum plate materials.

  In the aluminum resin composite laminate of the present invention, the synthetic resin layer is preferably made of a foamed polypropylene resin having an expansion ratio of 2 times or more.

  By using such a foamed resin as a core material, excellent sound insulation and heat insulation can be exhibited.

  In the aluminum resin composite laminate of the present invention, it is desirable to provide an adhesive layer mainly composed of polypropylene resin between the aluminum material and the synthetic resin layer.

  By providing such an adhesive layer, the adhesion between the aluminum material on both sides and the synthetic resin layer that is the core material is increased, and peeling at the interface between the aluminum material and the core material resin during three-dimensional molding and subsequent use Can be suppressed.

  The aluminum resin composite laminate of the present invention preferably has a tensile strength of 20 MPa to 60 MPa, a proof stress of 5 MPa to 40 MPa, and an elongation of 15% or more.

  By using a composite laminate having such characteristics, a three-dimensional product can be molded in a stable shape.

  In the aluminum resin composite laminate of the present invention, it is desirable that the limit drawing ratio in the cylindrical drawing in the temperature range from room temperature to less than 150 ° C. is 2.1 or more.

  When the limit drawing ratio is 2.1 or more, a more complicated three-dimensional shaped product can be manufactured with a high yield. For example, in the rectangular tube-shaped drawing forming, which is more difficult to process than a cylinder, a metal plate and a resin need to be evenly deformed, and hence higher formability is required as a composite laminated plate.

It is possible to obtain a three-dimensional molded product with a smooth outer surface and excellent design, while ensuring good moldability by arranging and molding an aluminum plate material with a large thickness on the convex side (outer side) it can.
In this case, a good molded product can be obtained even at room temperature, but when the mold and the aluminum resin composite laminate are heated and molded, the molding can be performed more smoothly.

  According to the present invention, a product having a complicated three-dimensional shape can be molded without causing rough skin or cracks, and a three-dimensional molded product having a smooth outer surface and excellent design can be obtained.

It is sectional drawing of the aluminum resin composite laminated sheet of one Embodiment of this invention. It is sectional drawing which shows the state which installed the aluminum resin composite laminated board of FIG. 1 in the press molding die.

Hereinafter, an embodiment of an aluminum resin composite laminate according to the present invention and a method for producing a three-dimensional molded product using the same will be described.
The three-dimensional molded product of the present invention includes a cylindrical molded product such as a bottomed cylinder and a square tube with a bottom, a box-shaped molded product with one opening, a dome-shaped molded product, etc., one of which (usually the outer surface side). Is a convex surface, and the other (inner surface side) is a concave surface. In addition, the shape which has a concave surface in a certain range is included in a part of the convex surface.
As schematically shown in FIG. 1, the aluminum resin composite laminate 1 has a configuration in which aluminum plates 3 and 4 are laminated on both surfaces of a synthetic resin layer 2, respectively. In the following, one of the aluminum plate members (the side that becomes the convex surface in the three-dimensional forming) is referred to as a first aluminum plate member 3, and the other aluminum plate member is referred to as a second aluminum plate member 4.

<First aluminum plate>
The first aluminum plate 3 contains magnesium in an amount of 1.5 mass% to 1.8 mass%, copper in an amount of 0.01 mass% or less, the balance is made of aluminum and inevitable impurities, and the tensile strength is 150 MPa to 170 MPa. The proof stress is preferably 55 MPa or more and 75 MPa or less, and the elongation is 15% or more.

Magnesium has the effect of high solid solution hardening by dissolving in aluminum, and has the effect of increasing the strength of the material and increasing the rigidity of the aluminum plate. When the magnesium content is less than 1.5% by mass, the effect of increasing strength and rigidity is insufficient, and when it exceeds 1.8% by mass, three-dimensional molding becomes difficult.
Copper also has the effect of increasing the strength of the material by being dissolved in aluminum, but if the content exceeds 0.01% by mass, the variation in strength increases and the formability is impaired.

  When the tensile strength of the first aluminum plate 3 is 150 MPa or more and 170 MPa or less, the proof stress is 55 MPa or more and 75 MPa or less, and the elongation is 15% or more, molding defects such as rough skin and cracks are maintained while maintaining desired strength and rigidity. Can be effectively prevented, the spring back is small, and the molded three-dimensional shape can be maintained. The values of tensile strength, proof stress, and elongation can be adjusted by subjecting a plate cold-rolled to a predetermined final product thickness to final annealing called temper annealing (or stabilization annealing).

  The thickness of the first aluminum plate 3 is preferably 0.2 mm or more and 0.5 mm or less in order to give strength and rigidity. In this case, it is important that the thickness of the first aluminum plate 3 is larger than the thickness of the second aluminum plate 4. When the three-dimensional molded product is arranged and molded such that the first aluminum plate 3 is on the outer surface side, it is possible to prevent the occurrence of rough skin, cracks, etc. on the outer surface and to form the surface in a good surface state.

<Second aluminum plate>
The second aluminum plate 4 contains 0.01 mass% or more and 0.03 mass% or less of copper (Cu), the balance is made of aluminum and inevitable impurities, the tensile strength is 60 MPa or more and 80 MPa or less, and the proof stress is 50 MPa or more and 70 MPa. Hereinafter, the elongation is preferably 20% or more.
In this second aluminum plate material, a small amount of copper is added for the purpose of improving the deformability while maintaining the necessary strength. Addition of magnesium (Mg) contributes to improvement in strength but is inferior in moldability. The addition of copper has the effect of improving the strength and improving the formability. However, caution is necessary because excessive addition of copper tends to cause corrosion.
For this reason, content of copper was made into 0.01 mass% or more and 0.03 mass% or less. If the content is less than 0.01% by mass, strength and rigidity are insufficient, and if it exceeds 0.03% by mass, molding defects such as cracks are likely to occur. Some 1000 series aluminum falls under JIS standards.

  When the tensile strength of the second aluminum plate 4 is 60 MPa or more and 80 MPa or less, the proof stress is 50 MPa or more and 70 MPa or less, and the elongation is 20% or more, the balance between the strength and rigidity of the first aluminum plate 3 described above in the composite laminate. As a result, the three-dimensional molded product can be molded with a high yield. For the second aluminum plate, as in the first aluminum plate, the values of tensile strength, proof stress, and elongation are the final values called temper annealing (or stabilization annealing) for a plate cold-rolled to a predetermined final product thickness. It can be adjusted by annealing.

  The thickness of the second aluminum plate 4 is smaller than the thickness of the first aluminum plate 3 and is preferably 0.1 mm to 0.4 mm. By making the second aluminum plate 4 thinner than the first aluminum plate 3, the unevenness of the synthetic resin layer is absorbed by the second aluminum plate 4 when used on the inner surface side of the three-dimensional molded product. It is possible to prevent deformation (rough skin) from occurring in the first aluminum plate 3 on the outer surface side. Moreover, it is more preferable in terms of the three-dimensional formability of the composite laminate that the difference in thickness (plate thickness difference) between the first aluminum plate 3 and the second aluminum plate 4 is 0.2 mm or more.

<Synthetic resin layer>
The synthetic resin layer 2 is made of polyethylene, polypropylene, polystyrene, polyurethane, polyethylene terephthalate, polycarbonate, or the like, and is formed in a film shape or a plate shape having a thickness of 1 mm to 10 mm. In this case, a foamable resin in which bubbles are dispersed may be used, and by using a foamable resin that is uniformly dispersed at a foaming ratio of 2 times or more, more preferably 3 times or more, a resin having excellent sound insulation and heat insulation properties. It becomes. In addition, as long as the temperature at the time of processing does not exceed the melting temperature (melting point) of the resin to be used, the foaming ratio of the synthetic resin does not greatly affect the workability and moldability of the composite laminate. Further, the melting point of the synthetic resin is desirably 100 ° C. or higher, and when performing highly difficult three-dimensional molding, warm molding is performed in which the mold and material are heated to about 140 ° C. In some cases, the melting point of the synthetic resin is preferably 150 ° C. or higher.

<Characteristics and manufacturing method of aluminum resin composite laminate>
As a whole, the aluminum resin composite laminated plate 1 formed by laminating both the aluminum plate members 3 and 4 and the synthetic resin layer 2 thus configured has a tensile strength of 20 MPa to 60 MPa, a proof stress of 5 MPa to 40 MPa, and an elongation. It is good that it is 15% or more, and a three-dimensional product can be molded in a stable shape. More desirably, the elongation of the composite laminate is 17.5% or more in terms of formability.

This aluminum resin composite laminate 1 is manufactured by preparing a synthetic resin layer 2 and both aluminum plates 3 and 4 and laminating them through an adhesive. It is preferable to select the main component of the same resin as the material of the synthetic resin layer of the core material for securing the necessary adhesive. For example, when the synthetic resin layer 2 serving as the core material is made of polypropylene, an adhesive mainly composed of polypropylene is suitable.
This adhesive is applied to both surfaces of the synthetic resin layer 2 or one side of both aluminum plates 3 and 4, and the synthetic resin layer 2 is sandwiched between both aluminum plates 3 and 4, and these are pressed and hot-pressed or hot-rolled. By heating, the aluminum plate materials 3 and 4 are integrally laminated on both surfaces of the synthetic resin layer 2.

<Manufacture of three-dimensional molded products>
When a three-dimensional molded product is manufactured using the aluminum resin composite laminate 1 obtained in this way, as shown in FIG. 2, the first aluminum plate 3 is placed on the pressing die 11 and the outer surface of the molded product. Arrange so that At this time, when the depth of the molded product is small, it is molded at room temperature, but when it is a molded product with a complicated shape, the mold surface and the aluminum resin composite laminate are preheated to perform warm molding. Do. As the temperature of the warm molding, a higher temperature is more advantageous for molding, but the temperature is less than the melting point of the synthetic resin, for example, less than 150 ° C., and is appropriately set according to the shape of the molded product, temperature variation, and the like.
In FIG. 2, the pressing die 11 includes a die 13 having a forming hole 12, a punch 14, and a wrinkle retainer 15.

  Then, a three-dimensional molded product is manufactured by press molding. At this time, the aluminum resin composite laminate 1 is a bent portion that is a large process, and the synthetic resin layer 2 that is a core material is easily deformed into an uneven shape. In this aluminum resin composite laminate 1, the first aluminum plate 3 arranged on the outer surface side is formed thicker than the second aluminum plate 4 arranged on the inner surface side, and the strength and rigidity are higher than those of the second aluminum plate 4, On the other hand, since the second aluminum plate 4 disposed on the inner surface side is small in thickness and can be easily deformed, the unevenness generated in the synthetic resin layer 2 is deformed by the second aluminum plate 4 on the inner surface side of the molded product. And the occurrence of rough skin and cracks in the first aluminum plate 3 on the outer surface side is prevented. By warm molding, the moldability is further improved and the surface can be smoothed.

  Samples of an aluminum resin composite laminate were produced using the combinations shown in Table 1 for the composition, plate thickness, mechanical properties, material of the synthetic resin layer, and thickness of the aluminum plate material. For mechanical properties, No. 5 test piece of JIS-Z2241 was prepared and subjected to a tensile test, and tensile strength, 0.2% proof stress and elongation were measured. In addition, polyethylene (melting point 100 ° C.) or polypropylene (melting point 150 ° C.) was selected as the synthetic resin layer material, and the expansion ratio was 2.5 times. As the adhesive, an adhesive mainly composed of polypropylene was used for the composite laminate having the synthetic resin layer of polyethylene, and an adhesive mainly composed of polypropylene was used for the composite resin layer having the polypropylene.

The moldability of the obtained composite laminate sample was evaluated by a cylindrical drawing test and a rectangular tube drawing test. In both tests, the mold / material temperature was set to 90 ° C. for a composite laminate made of polyethylene as a synthetic resin layer and 140 ° C. for a composite laminate made of polypropylene as a synthetic resin layer.
The moldability was evaluated by drawing a sample into a cylindrical container with a punch having a diameter of 33 mm, and changing the blank diameter at that time, so that the drawing ratio (blank diameter / punch diameter) was 1.7, 1.8, Six types of containers of 1.9, 2.0, 2.1, and 2.2 were molded. In both cases, the forming speed was 200 mm / min, and the wrinkle holding force around the punch was 3 kN. Formability is evaluated by inspecting the appearance of the molded product, and in each of the five moldings, “◎” indicates that the molding can be performed five times, and “◯” indicates that the molding can be performed four or three times. The case where it was able to be molded twice out of 5 times was “Δ”, and the case where it was able to be molded once in 5 times was “x”. In the pass / fail judgment, “◎” and “○” were determined to be acceptable and “Δ” and “×” were determined to be unacceptable based on the correlation with the formability of the actual product shape and size.
The results are shown in Table 2.

  Further, in order to investigate the adaptability to processing with a higher degree of difficulty, the drawing ratio is 1.8, 1.9, 2.0, 2 for a square tube diaphragm (die corner R = 3 mm) that is a square with a side of 40 mm. A square tube drawing test was performed on six types of containers 1, 2, and 2.3 under conditions of a molding speed of 2 mm / second and a wrinkle holding force of 5 kN. The appearance of the molded product at this time was evaluated in the same manner as in the previous section.

  As can be seen from the results in Table 2, the aluminum resin composite laminates of Examples 1 to 20 exhibit generally good formability in processing of a drawing ratio of 2.1 or less in cylindrical and rectangular tube deep drawing. On the other hand, in Comparative Examples 1 to 12, even when the cylindrical drawing is relatively good (Comparative Examples 1, 8 to 10 and 12), sufficient formability is obtained in the more difficult rectangular tube drawing. However, it is difficult to apply to actual molding that requires processing into various shapes, which is not preferable as a three-dimensionally molded laminate.

  In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Aluminum resin composite laminated board 2 Synthetic resin layer 3 1st aluminum board material (aluminum board material of the side used as a convex surface)
4 Second aluminum plate (the other aluminum plate)
11 Die for press 12 Molding hole 13 Die 14 Punch 15 Wrinkle retainer

Claims (8)

  In the aluminum synthetic resin composite laminated plate used for molding a three-dimensional molded product in which an aluminum plate material is laminated on both surfaces of a synthetic resin layer, and either side is convex and the other side is concave, the aluminum plate material on the convex surface side Contains not less than 1.5% by mass and not more than 1.8% by mass of magnesium and 0.01% by mass or less of copper, and the balance is made of aluminum and inevitable impurities, and the other aluminum plate material has 0.01% by mass of copper. % Or more and 0.03% by mass or less, the balance is made of aluminum and inevitable impurities, and the thickness of the aluminum plate on the convex surface side is larger than the thickness of the other aluminum plate. Aluminum resin composite laminate.   The aluminum plate on the convex surface side has a tensile strength of 150 MPa or more and 170 MPa or less, a proof stress of 55 MPa or more and 75 MPa or less, and an elongation of 15% or more, and the other aluminum plate material has a tensile strength of 60 MPa or more and 80 MPa or less, The aluminum resin composite laminate according to claim 1, wherein the proof stress is 50 MPa or more and 70 MPa or less, and the elongation is 20% or more.   The aluminum plate on the convex surface side has a thickness of 0.2 mm to 0.5 mm, and the other aluminum plate has a thickness of 0.1 mm to 0.4 mm. The thickness of the synthetic resin layer The aluminum resin composite laminate according to claim 1 or 2, wherein the length is from 1 mm to 10 mm.   The aluminum resin composite laminate according to any one of claims 1 to 3, wherein the synthetic resin layer is made of a synthetic resin having a melting point of 100 ° C or higher.   The aluminum resin composite laminate according to any one of claims 1 to 4, wherein the synthetic resin layer is a polypropylene resin having an expansion ratio of 2 times or more.   The aluminum resin composite laminate according to claim 5, wherein an adhesive layer mainly composed of polypropylene is provided between the aluminum plate and the synthetic resin layer.   The aluminum resin composite laminate according to any one of claims 1 to 6, wherein the tensile strength is 20 MPa or more and 60 MPa or less, the proof stress is 5 MPa or more and 40 MPa or less, and the elongation is 15% or more. The aluminum resin composite laminate according to any one of claims 1 to 7, wherein a limit drawing ratio in cylindrical drawing in a temperature range from room temperature to less than 150 ° C is 2.1 or more.

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