JP2018012108A - Press molding method of aluminum resin composite laminated plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a press molding method of an aluminum resin composite laminated plate capable of molding a square molded article which can improve moldability and has good appearance characteristics.SOLUTION: A press molding method of an aluminum resin composite laminated plate includes a heating step of heating a blank material and a molding step of drawing the heated blank material using a press molding die having a punch and a die, where the heating step includes heating the blank material to a temperature which is equal to or lower than a heat-resistant temperature of a foamed synthetic resin layer and shows a temperature difference between the temperature and the temperature of the heat-resistant temperature of the foamed synthetic resin layer of higher than 10°C and 22°C or lower, and sets a temperature of an inner surface of a concave surface of the square molded article in the blank material to be higher than a temperature of an outer surface to be a convex surface of the square molded article by 3°C or higher.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a press molding method for press-molding an aluminum resin composite laminated plate obtained by laminating an aluminum plate and a foamed synthetic resin layer to form a square molded product.

  In recent years, in the plate-like member used for various uses, weight reduction of a material is a big subject, and it is not limited to the automobile field, but it is a railway vehicle, an aircraft, a ship and other transportation equipment, a household appliance, an IT related member, and There is a need to reduce the weight of houses and outer wall materials such as buildings. As an example, in an automobile, replacement of a part of a steel plate used for vehicle parts with an aluminum plate, a resin plate, or a CFRP (carbon fiber reinforced plastic) plate has been studied. Furthermore, depending on the application, in addition to light weight, additional performance such as vibration control, sound insulation, and heat insulation is often required. As one of the plate materials to meet such demands, two aluminum It has been proposed to use an aluminum resin composite laminate in which a synthetic resin layer is sandwiched between plates. And this kind of laminated board is normally processed by press molding.

  For example, Patent Document 1 discloses a laminated plate in which a foamable resin layer is provided between two aluminum alloy plates. Patent Document 2 discloses an example in which the laminated plate described in Patent Document 1 is applied to a lightweight heat ray shielding cover having a three-dimensional shape and excellent heat ray shielding properties, such as a heat insulator. Furthermore, in Patent Document 2, as a method of forming the laminated plate, press forming such as bulging forming, drawing forming, bending forming, and bending can be performed, and the resin layer is foamed by heating after the forming processing. Is described.

  In Patent Document 3, a thermoplastic resin layer and an aluminum material are laminated, and a surface layer of the aluminum material is provided with a porous aluminum oxide film layer having a small diameter on the surface side, and a barrier type on the substrate side. An aluminum oxide film layer is provided, and a non-foamed resin layer of the same component as the thermoplastic foam resin layer is formed on the porous aluminum oxide film layer from the surface thereof at the joint between the aluminum material and the thermoplastic foam resin layer. An aluminum material / thermoplastic foamed resin layer composite formed toward the inside of the small holes is disclosed. Patent Document 3 describes that by adopting such a configuration, a composite material having excellent adhesion and formability is obtained.

  In Patent Document 4, aluminum having a higher strength than the inner aluminum plate is used for the outer aluminum plate at the time of press molding, and the outer aluminum plate thickness is equal to or thicker than the inner aluminum plate thickness. An aluminum alloy press-molding composite plate is disclosed. In Patent Document 4, when the strength of the outer and inner aluminum plates is relatively viewed, a high strength material is used on the outer side, a low strength material is used on the inner side, and the outer plate thickness is equal to the inner plate thickness. Alternatively, it is described that, by increasing the thickness, it is possible to prevent the occurrence of cracks during press molding, and an aluminum composite plate having excellent press moldability is obtained.

International Publication No. 2010/029955 International Publication No. 2010/029946 JP 2012-25145 A JP-A-4-43027 JP 2013-116475 A JP 2014-18854 A JP 2009-242240 A

  By the way, as disclosed in, for example, Patent Documents 5 to 7, when forming a metal plate conventionally formed of a single metal, generation of wrinkles and cracks is prevented, and further, a spring back after forming is prevented. A molding method for reducing the number has been proposed. However, when a composite laminate as described in Patent Documents 1 to 4 is formed by the same method as Patent Documents 5 to 7, it is press-molded into a two-dimensional product or a three-dimensional product with a slight depth. It is useful in some cases, but if it is molded into a deeper and more complex shape (such as a square-shaped molded product), the surface of the aluminum sheet cannot prevent rough skin, wrinkles, cracks, etc. It is a problem to cause defects. Moreover, even if it forms the highly difficult three-dimensional shape as a composite laminated board described in patent document 4, it is difficult to prevent generation | occurrence | production of a crack etc. and cannot perform stable shaping | molding. 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. In addition, there is an attempt to ensure moldability by foaming the core resin after molding as in Patent Document 1 or 2, but it is easy to cause changes in the dimensions of the laminate and distortion in the resin foam after molding. There is a high risk of becoming an obstacle during assembly.

  The present invention has been made in view of such circumstances, and can improve the formability when producing a square molded product using an aluminum resin composite laminate by press molding, and has a good appearance characteristic. It aims at providing the press molding method of the aluminum resin composite laminated board which can shape | mold a molded article.

  In the press molding method of an aluminum resin composite laminate of the present invention, a blank material made of an aluminum resin composite laminate obtained by bonding an aluminum plate to both sides of a foamed synthetic resin layer is drawn into a rectangular rectangular shaped product with a bottom. A heating process for heating the blank material, and a molding process for performing drawing using a press molding die provided with a punch and a die on the heated blank material, In the heating step, the blank material is heated to a temperature lower than the heat resistant temperature of the foamed synthetic resin layer and a temperature difference from the heat resistant temperature of the foamed synthetic resin layer to more than 10 ° C and not more than 22 ° C. In addition, the temperature of the inner surface of the blank material to be the concave surface of the square-shaped molded product is higher by 3 ° C. than the temperature of the outer surface of the blank-shaped molded product to be the convex surface. Keep heated to a temperature.

The aluminum resin composite laminated plate is very difficult to be drawn compared to the case of forming a metal plate formed of a single metal. In other words, since the appropriate molding conditions differ between the foamed synthetic resin and aluminum, the difference in deformation amount between the foamed synthetic resin layer formed of the foamed synthetic resin that is the core material and the aluminum plate disposed on both surfaces thereof. Appearance defects are likely to occur due to the occurrence of rough skin, wrinkles, cracks, etc. including fine irregularities on the surface of the aluminum plate. Further, the difference in deformation amount between the convex surface side and the concave surface side of the square-shaped molded product to be molded may promote the appearance defect that occurs on the surface of the aluminum plate. For this reason, in the aluminum resin composite laminate composed of three layers in which the aluminum plate material is laminated on both surfaces of the foamed synthetic resin layer, it must be molded in consideration of the molding conditions and the amount of deformation for each of these materials, The process is complicated.
In this regard, in the press molding method of the present invention, the blank material of the aluminum resin composite laminate can be heated to a temperature near the heat-resistant temperature at which the foamed synthetic resin as the core does not elute, thereby enabling stable warm molding. By providing a temperature difference of 3 ° C. or more between the outer surface and the inner surface of the blank material and providing a deformability difference between the outer surface and the inner surface, a square-shaped molded product is obtained due to the difference in deformation (molding amount) between the outer surface and the inner surface. It can prevent that the crack of wrinkles and wrinkles arises on the surface. By controlling the temperature of the blank material in this way, it is possible to improve the formability when manufacturing a square-shaped product using an aluminum resin composite laminate by press molding, so that a deep corner having good appearance characteristics can be obtained. Molded products can be manufactured.
If the temperature difference between the temperature of the blank material and the heat resistant temperature of the foamed synthetic resin is 10 ° C. or less, the foamed synthetic resin of the foamed synthetic resin layer may be eluted. Moreover, when it is set as the temperature difference over 22 degreeC, a foaming synthetic resin layer cannot change easily, and a moldability falls because the effect of warm shaping | molding is not fully acquired. In addition, when the temperature difference between the outer surface and the inner surface of the blank is less than 3 ° C., it is not possible to impart a deformability difference and prevent generation of wrinkles and the like. The temperature difference between the outer surface and the inner surface is desirably 12 ° C. or less. When the temperature difference between the outer surface and the inner surface exceeds 12 ° C., the temperature difference is too large, particularly the deformability on the outer surface side is inferior, and molding becomes difficult. In addition, since the heat on the inner surface side is abruptly taken to the outer surface side, the temperature on the inner and outer surfaces is difficult to stabilize.

  In the molding step of the press molding method for the aluminum resin composite laminate of the present invention, the temperature of the die may be heated to a temperature lower than the temperature of the blank material within a range of 5 ° C to 20 ° C. .

  Of the press molding dies, at least the die that contacts the outer surface of the blank material is heated to a temperature close to the temperature of the blank material, so that the temperature drop of the blank material can be prevented and stable warm forming can be performed. it can. Moreover, it can shape | mold, maintaining the temperature difference of the outer surface of a blank material, and an inner surface by setting the temperature of a press-molding die to the temperature lower within the range of 5 degreeC or more and 20 degrees C or less than the temperature of a blank material.

  In the press molding method of the aluminum resin composite laminate of the present invention, the heating step is performed using a pair of heat transfer plates, and each heat transfer plate of the pair of heat transfer plates is heated by separate heating means. It is good to heat each of the outer surface and the inner surface of the blank material through each heat transfer plate by sandwiching the outer surface and the inner surface of the blank material between the pair of heat transfer plates.

  A blank material is sandwiched between a pair of heat transfer plates, and each heat transfer plate is brought into contact with the outer surface and the inner surface of the blank material and heated, so that the inner surface and the outer surface of the blank material are brought into contact with each other by the heat transfer plates in contact with each other. Quick heating in the direction. And since the inner surface and the outer surface of the blank material can be heated to a temperature having a uniform temperature difference according to the temperature of each heat transfer plate, the core material can be reduced while reducing the temperature difference between the inner surface and the outer surface of the blank material. It is possible to realize temperature control in a high temperature range where the foamed synthetic resin is heated to near the heat-resistant temperature where it does not elute, and stable warm molding can be performed.

The heat transfer plate may be formed of an aluminum material.
Aluminum is more stable in heating temperature than materials other than aluminum, and the temperature of the inner and outer surfaces of the blank can be easily controlled by forming the heat transfer plate with an aluminum material.

The heating means may be a far infrared heater.
The far-infrared heater is capable of rapid heating and is excellent in stability of the temperature holding performance. Therefore, by using the far-infrared heater as the heating means, the outer surface and the inner surface of the blank can be quickly heated.

  In the press molding method of the aluminum resin composite laminate of the present invention, the blank synthetic material layer has a foaming ratio of 1.5 to 10 times and a plate thickness of 1 to 10 mm. An aluminum resin composite laminate may be used.

  In the foamed synthetic resin layer having a foaming ratio of less than 1.5 times and a plate thickness of less than 1 mm, the heat shielding property between the outer and inner surfaces of the blank material is lowered, so that it is difficult to provide a temperature difference between the outer surface and the inner surface. On the other hand, in a foamed synthetic resin layer having an expansion ratio exceeding 10 times and a plate thickness exceeding 10 mm, uniform workability is lowered. In addition, when the expansion ratio exceeds 10 times, a uniform and stable foamed state cannot be obtained, and problems such as cracks and wrinkles due to local deformation are likely to occur in the processing of the aluminum resin composite laminate.

  According to the present invention, the blank material is provided with a temperature difference that takes into account the amount of deformation between the outer surface and the inner surface of the blank material while heating to a high temperature region near the heat-resistant temperature where the foamed synthetic resin as the core material does not elute. Since stable warm forming can be performed, it is possible to improve moldability when a square shaped product is produced by press molding, and it is possible to produce a deep shaped square shaped product having good appearance characteristics.

It is a flowchart of the press molding method of 1st Embodiment of this invention. It is a schematic cross section of the heating apparatus used for the heating process of the press molding method of 1st Embodiment. It is a model perspective view of the press molding die used for the forming process of the press forming method of the first embodiment. It is principal part sectional drawing of the aluminum resin composite laminated board used for this invention. It is a perspective view which shows the example of the square shape molded article shape | molded by this invention. It is a flowchart of the press molding method of 2nd Embodiment of this invention. It is a model perspective view of the press molding die used for the 1st formation process of the press molding method of a 2nd embodiment. It is a schematic cross section of the heating apparatus used for the 2nd heating process of the press molding method of 2nd Embodiment. It is a model perspective view of the press molding die used for the 2nd shaping | molding process of the press molding method of 2nd Embodiment. It is a perspective view which shows the example of the intermediate molded product of the square shape molded product shape | molded by this invention.

Hereinafter, an embodiment of a press molding method for an aluminum resin composite laminate according to the present invention will be described.
As shown in FIG. 5, the square molded product 60 molded by the press molding method of the aluminum resin composite laminate of the first embodiment of the present invention has a bottomed shape and is formed in a rectangular shape, and one is opened. It is a box-shaped molded product. Specifically, the square molded product 60 is a tube such as a bottomed square tube in which a plurality of corner portions 62 and a side surface portion 63 that connects the corner portions 62 are formed on a rectangular bottom portion 61. One (outer surface side) is a convex surface and the other (inner surface side) is a concave surface.

[Structure of aluminum resin composite laminate]
As schematically shown in FIG. 4, the aluminum resin composite laminated plate 10 used in the present invention has a configuration in which aluminum plate materials 11 and 12 are joined to both surfaces of a foamed synthetic resin layer 13 in a laminated state. The surface of the aluminum plate 11 that is to be the convex surface 60a in the square molded product 60 is the outer surface 10a, and the surface of the aluminum plate 12 that is to be the concave surface 60b in the square molded product 60 is the inner surface 10b.

  The types of the aluminum plate 11 on the outer surface side and the aluminum plate 12 on the inner surface side are not particularly limited, but in order to form the aluminum resin composite laminate 10 deeper, the mechanical properties of the aluminum plate 11 on the outer surface side. (Tensile strength, yield strength, etc.) may be larger than the aluminum plate 12 on the inner surface side.

  The thickness of each of the aluminum plate members 11 and 12 is not particularly limited, but it is preferable that the aluminum resin composite laminated plate 10 have a thickness that can give desired strength and rigidity. For this purpose, the thickness of the aluminum resin composite laminate 10 is preferably 2 mm or more and 10 mm or less, and the thickness of the aluminum plates 11 and 12 on both sides is preferably 0.1 mm or more and 4 mm or less. The aluminum plate 11 on the outer surface 10a side is preferably thinner.

  In addition, the aluminum plate materials 11 and 12 as described above are obtained by performing a semi-continuous casting, a homogenization process, a hot rolling, a cold rolling, and an intermediate annealing as required by performing a conventional method. A plate having mechanical properties can be produced. Moreover, the molten metal rolling method like continuous casting rolling can also be used as a cold rolling raw material.

On the other hand, the foamed synthetic resin layer 13 is a thermoplastic resin having a heat resistant temperature in the range of 100 ° C. or higher and 200 ° C. or lower. Specifically, polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyethylene terephthalate. (PET), polyvinylidene chloride (PVDC), polybutylene terephthalate (PBT), polyvinylidene fluoride (PVDF), polyamide (PA6, PA12, etc.), polyetherimide (PEI), polysulfone (PSF), polychlorotrifluoro Any of ethylene (PCTFE) can be used.
For example, when the foamed synthetic resin layer 13 is polypropylene, the melting point is around 170 ° C. and the heat resistant temperature is around 140 ° C. The deflection temperature under load is around 77 ° C., and the aluminum resin composite laminate 10 is press-molded at a temperature equal to or higher than the deflection temperature under load as will be described later.

Here, the heat-resistant temperature of the resin and the deflection temperature under load are determined based on whether or not the resin test piece is placed in a certain temperature for a predetermined time and the appearance changes or the mechanical characteristics are deteriorated at that time.
In JIS (Japanese Industrial Standard), it is a temperature obtained by a test method (Method A, flatwise) defined in Plastics-How to obtain deflection temperature under load (JIS K 7191), and forms a foamed synthetic resin layer 13. It represents the temperature at which the foamed synthetic resin deforms when it receives a certain load (also referred to as heat deformation temperature). For example, it is determined that the temperature range is 110 to 180 ° C. and the time is 2 hours. Under this condition, the heat-resistant temperature is a temperature at which the product can be maintained without being deformed and deformed in a state where the product such as the resin container is not subjected to force, and the deflection temperature under load is a force that the product such as the resin container receives. It becomes the temperature which causes deformation in the state. In the case of polypropylene, the temperatures are as described above, and the relationship is such that the heat resistance temperature> the deflection temperature under load.

The foamed synthetic resin layer 13 is formed in a film shape or plate shape having a plate thickness of 1 mm or more and 10 mm or less, and has an expansion ratio of 1.5 times or more and 10 times or less in order to provide sound insulation and heat insulation. Is used. If the expansion ratio is less than 1.5 times, it is insufficient in terms of vibration damping, sound insulation, and heat insulation. Conversely, if the expansion ratio exceeds 10 times, a uniform and stable foam state cannot be obtained, and processing of an aluminum resin composite laminate Causes problems such as cracks and wrinkles due to local deformation.
The foamed synthetic resin layer 13 and the aluminum plate members 11 and 12 are preferably bonded together, and in this case, the adhesive may be selected from the material of the foamed synthetic resin layer 13 that is the core material and the main component of the same resin. Preferably, when the foamed synthetic resin layer 13 is polypropylene, an adhesive mainly composed of polypropylene is suitable.

  And this adhesive agent is apply | coated to both surfaces of the foamed synthetic resin layer 13, or one side of the aluminum board | plate materials 11 and 12, sandwiching the foamed synthetic resin layer 13 between both the aluminum board | plate materials 11 and 12, these are hot-pressed or hot-rolled. By pressurizing and heating, aluminum plate materials 11 and 12 are integrally laminated on both surfaces of the foamed synthetic resin layer 13 to provide an aluminum resin composite laminate.

  The aluminum resin composite laminate 10 thus formed is punched into a blank material having an appropriate shape, and a square molded product 60 having a depth of 10 mm or more is manufactured by the press molding method of the present invention. Hereinafter, the blank material will be described with the same reference numeral 10 as that of the aluminum resin composite laminate.

  As shown in FIG. 1, the press molding method of the first embodiment is performed in the order of a heating step and a molding step. And in the heating process of the press molding method of this embodiment, the heating apparatus 20 shown in FIG. 2 is used, and in the molding process, the press molding die 30 shown in FIG. 3 is used.

As shown in FIG. 2, the heating device 20 includes a pair of heat transfer plates 21 and 22 and heating means 23 and 24 that heat the heat transfer plates 21 and 22. In the present embodiment, the heat transfer plates 21 and 22 are formed in a flat plate shape from an aluminum material. Further, far infrared heaters are used for the heating means 23 and 24.
The heat transfer plate 21 disposed on the upper side of the heating device 20 has a lower surface 21b that is a heating surface of the outer surface 10a of the blank member 10, and is formed in a flat shape. The heating means 23 is installed on the upper surface 21t of the heat transfer plate 21. On the other hand, the upper surface 22t of the heat transfer plate 22 disposed on the lower side of the heating device 20 is a heating surface of the inner surface 10b of the blank 10 and is formed in a flat shape. A heating unit 24 is installed on the lower surface 22 b of the heat transfer plate 22.

  Further, temperature measuring means (for example, thermocouple type measuring devices) 25A and 25B are embedded in (incorporated into) each of the heat transfer plates 21 and 22, and each heat measuring means 25A and 25B is provided with each heat. By measuring the temperatures of the transfer plates 21 and 22 and controlling the heating means 23 and 24 based on the measured values, the upper heat transfer plate 21 and the lower heat transfer plate 22 are independently temperature controlled. It is provided as possible. Further, the upper heat transfer plate 21 of the heating device 20 is held so as to be vertically movable with respect to the lower heat transfer plate 22, and by moving the upper heat transfer plate 21 up and down, the heat transfer plate 21. , 22 can be opened and closed. And the blank material 10 is arrange | positioned between a pair of heat-transfer plates 21 and 22, and the outer surface 10a and the inner surface 10b of the blank material 10 are pinched | interposed by a pair of heat-transfer plates 21 and 22 between the outer surface 10a and the inner surface 10b. Heating can be performed individually and simultaneously via the heat transfer plates 21 and 22.

  As shown in FIG. 3, the press molding die 30 includes a die 31 having a molding square hole 31 h having substantially the same shape as the bottom 61 of the square molded product 60 to be molded, and a molding square hole 31 h of the die 31. A blank holder 32 that has a shaped through-angle hole 32h and holds the blank material 10 between the surface of the die 31 and a blank material 10 that is inserted into the forming square hole 31h and the through-angle hole 32h to be drawn. And a prismatic punch 33 that can squeeze the bottom 61 of the molded product 60.

Although not shown, the die 31 and the blank holder 32 incorporate a plurality of rod-shaped heaters for heating in advance prior to molding. The die 31 and the blank holder 32 incorporate temperature measuring means 35A and 35B, and the die 31 and the blank holder 32 are provided so that the temperature can be adjusted independently. For the temperature measuring means 35A, 35B, for example, a thermocouple type measuring instrument having a rod-shaped tip is used. Note that, similarly to the die 31 and the blank holder 32, the punch 33 may be heated.
Further, a heat insulating material 102 is provided on a mounting surface 31 m of the die 31 with the press machine body 101. Since the heat of the die 31 and the blank holder 32 can be prevented from being transmitted to the press machine body 101 by the heat insulating material 102, the temperature drop of the die 31 and the blank holder 32 can be prevented.

  Although not shown, the blank holder 32 is provided with a guide hole through which a guide rod for supporting the body portion of the blank holder 32 so as to be movable up and down is provided, and the blank holder 32 is urged downward. An elastic member such as a spring is provided.

[Press molding method for square-shaped molded products]
In the press molding method of the present embodiment, the blank material 10 is subjected to deep drawing through a heating process using the heating device 20 and a molding process using the press mold 30, and the square molded product 60. Manufacturing.

[Heating process]
In the heating step, the blank material 10 is heated to a temperature lower than the heat resistant temperature of the foamed synthetic resin layer 13 and a temperature difference from the heat resistant temperature of the foamed synthetic resin layer 13 to more than 10 ° C. and not more than 22 ° C. At the same time, the temperature of the inner surface 10b is heated to 3 ° C. or more higher than the temperature of the outer surface 10a. In addition, as for the temperature difference of the outer surface 10a and the inner surface 10b, it is desirable to set it as 12 degrees C or less from a viewpoint of a moldability.
As described above, the heating process is performed using the heating apparatus 20 shown in FIG. Each heat transfer plate 21, 22 of the heating device 20 is heated by separate heating means 23, 24, and a temperature difference is provided in advance in each heat transfer plate 21, 22 and heated at the expected heating temperature of the blank 10. Keep it. And the blank material 10 is arrange | positioned between a pair of heated heat-transfer plates 21 and 22, and each heat-transfer plate 21 and 22 is pinched | interposed by a pair of heat-transfer plates 21 and 22 between the outer surface 10a and the inner surface 10b. Each of the outer surface 10a and the inner surface 10b of the blank material 10 is heated through the above. That is, the outer surface 10a of the blank member 10 is heated by bringing it into contact with the preheated heat transfer plate 21 and heated separately by bringing the inner surface 10b into contact with the heat transfer plate 22, but the outer surface 10a of the blank member 10 is heated. And the inner surface 10b between the pair of heat transfer plates 21 and 22, the outer surface 10a and the inner surface 10b can be heated simultaneously via the heat transfer plates 21 and 22.

  In this manner, the blank member 10 is sandwiched between the pair of heat transfer plates 21 and 22, the heat transfer plate 21 is brought into contact with the outer surface 10a of the blank member 10, and the heat transfer plate 22 is brought into contact with the inner surface 10b to be heated. Thereby, the outer surface 10a and the inner surface 10b of the blank material 10 can be rapidly heated in the surface direction by the heat transfer plates 21 and 22 that are in contact with each other. And since the outer surface 10a and the inner surface 10b of the blank material 10 can be heated to a temperature having a uniform temperature difference in accordance with the temperature of the heat transfer plates 21 and 22, the outer surface 10a and the inner surface 10b of the blank material 10 have 3 By providing a small temperature difference of not less than 0 ° C., temperature control can be realized in a high temperature range where the foamed synthetic resin as the core material is heated to near the heat-resistant temperature where it does not elute.

[Molding process]
In the molding step, the blank material 10 heated in the heating step is drawn using a press molding die 30.
The die 31 and the blank holder 32 of the press molding die 30 are heated in the heating process by heating respective heaters (not shown) provided before the blank material 10 is formed. It is heated to a temperature lower than the temperature within a range of 5 ° C. to 20 ° C. and heated at that temperature. Then, as shown in FIG. 3, the outer peripheral portion (peripheral portion) of the blank material 10 is pressed and sandwiched between the die 31 and the blank holder 32, and the blank material 10 is moved downward in this state to punch 33. Is inserted into the through-hole 32h of the blank holder 32 and the forming-angle hole 31h of the die 31, and the blank material 10 is drawn between the die 31 and the punch 33, and a square-shaped product 60 shown in FIG. Mold.

  At this time, since the die 31 and the blank holder 32 are preliminarily heated, when the outer peripheral portion of the blank material 10 is sandwiched between the die 31 and the blank holder 32, the temperature drop of the blank material 10 can be prevented. Moreover, since the temperature of the die 31 and the blank holder 32 is heated at a temperature close to the temperature of the blank material 10, that is, within a range of 5 ° C. or more and 20 ° C. or less than the temperature of the blank material 10, the blank material 10 can be molded while maintaining the temperature difference between the outer surface 10a and the inner surface 10b.

Thus, in the molding step, the foamed synthetic resin layer 13 that is the core material is heated to near the heat-resistant temperature where the foamed synthetic resin does not elute, and a temperature difference is provided between the outer surface 10a and the inner surface 10b of the blank material 10. That is, since the deformability difference is provided between the outer surface 10a and the inner surface 10b, the formability of the blank material 10 can be improved and stable warm forming can be performed. Therefore, a deeply molded square shaped product 60 can be manufactured while preventing generation of wrinkles and the like and obtaining good appearance characteristics.
In addition, the blank material 10 is made of an aluminum resin composite laminate having a foamed synthetic resin layer 13 having a foaming ratio of 1.5 to 10 times and a plate thickness of 1 to 10 mm. Can maintain sex.

  Note that if the temperature difference between the heating temperature of the blank 10 and the heat resistant temperature of the foamed synthetic resin is 10 ° C. or less, the foamed synthetic resin of the foamed synthetic resin layer 13 may be eluted. Moreover, when it is set as the temperature difference over 22 degreeC, the foaming synthetic resin layer 13 becomes difficult to deform | transform and a moldability falls because the effect of warm shaping | molding is not fully acquired. In addition, if the temperature difference between the outer surface 10a and the inner surface 10b of the blank 10 is less than 3 ° C., the deformability difference cannot be imparted to the outer surface 10a and the inner surface 10b, and the occurrence of wrinkles and the like cannot be prevented.

  Further, in the foamed synthetic resin layer 13 having a foaming ratio of less than 1.5 times and a plate thickness of less than 1 mm, the heat shielding property between the outer and inner surfaces of the blank material 10 is lowered, so that the temperature difference between the outer surface 10a and the inner surface 10b is increased. It becomes difficult to put on. On the other hand, in the foamed synthetic resin layer 13 having an expansion ratio exceeding 10 times and a plate thickness exceeding 10 mm, uniform workability is lowered. In addition, when the expansion ratio exceeds 10 times, a uniform and stable foam state cannot be obtained, and it becomes easy to cause defects such as cracks and wrinkles due to local deformation in the processing of the aluminum resin composite laminate, so that workability is reduced. is there.

In the press molding method of the first embodiment, the square molded product 60 is molded by a single molding process. However, the square molded product 60 is molded through a plurality of heating processes and molding processes. It is good to do.
For example, as shown in the flowchart of the press molding method of the second embodiment in FIG. 6, the heating process and the molding process are performed in the order of the first heating process, the first molding process, the second heating process, and the second heating process. By repeating twice alternately, the blank material 10 can be drawn in stages to form the square shaped product 60. In this case, after forming the intermediate molded product 50 shown in FIG. 7 through the first heating step and the first molding step, the intermediate molded product 50 (the present invention) is further passed through the second heating step and the second molding step. (Corresponding to the blank material) is drawn to form a final square shaped product 60 (FIG. 5) having a substantially prismatic shape.

Specifically, in the first heating step, the flat blank 10 is heated using the heating device 20 shown in FIG. 1 which is the same as the heating step of the press molding method of the first embodiment. Then, in the first molding step, the blank material 10 is mainly bent using a press molding die 70 shown in FIG. 8 to form an intermediate molded product 50 shown in FIG. In the second heating step, the intermediate molded product 50 is heated using the heating device 80 shown in FIG. Then, in the second molding step, a press molding die 90 shown in FIG. 10 is used to draw the intermediate molded product 50 heated in the second heating step, and the final square molded product 60 is molded.
As described above, in the press molding method of the second embodiment, the blank material 10 is predetermined by the first heating process or the second heating process performed before each molding process (first molding process or second molding process). After heating to temperature, processing is performed in each molding step.

Since the heating device 20 used in the first heating step is the same as the heating device 20 used in the first embodiment, description thereof is omitted.
As shown in FIG. 9, the heating device 80 used in the second heating step is similar to the heating device 20 (FIG. 2) used in the first heating step, and a pair of heat transfer plates 81 and 82 and each heat transfer plate 81. , 82 heating means (far infrared heaters in this embodiment) 83, 84, with a convex portion 81 d on the lower surface 81 b of the upper heat transfer plate 81 and a concave portion 82 c on the lower heat transfer plate 82. The intermediate molded product 50 that is provided and processed in the first molding step is sandwiched between the convex portion 81d and the concave portion 82c, thereby connecting the outer surface 50a and the inner surface 50b of the intermediate molded product 50 to the heat transfer plate 81, 82 can be heated individually and simultaneously.

  Similarly to the heating device 20 in the first heating step, the heating device 80 in the second heating step is also held so that the upper heat transfer plate 81 can move up and down with respect to the lower heat transfer plate 82. Further, individual temperature measuring means 85A and 85B are embedded in each heat transfer plate 81 and 82, and by controlling each heating means 83 and 84 based on the value of each temperature measuring means 85A and 85B, The upper heat transfer plate 81 and the lower heat transfer plate 82 are provided so that the temperature can be adjusted independently.

  The press molding die 70 used in the first molding step includes an upper die (punch) 71 and a lower die (die) 72. The upper die 71 is provided with a convex portion 71d and the lower die 72 is provided with a concave portion 72c. The convex portion 71d is formed in a tapered surface with a gentle molding surface. The concave portion 72c also has a gently tapered surface that engages with the convex portion 71d. And the blank material 10 is arrange | positioned between the convex part 71d and the recessed part 72c, and the intermediate molded product 50 shown in FIG. 7 can be shape | molded by bending this blank material 10 with the convex part 71d and the recessed part 72c.

  Although not shown, the upper mold 71 and the lower mold 72 incorporate a plurality of rod-shaped heaters for heating the upper mold 71 and the lower mold 72 in advance prior to molding. Further, the upper mold 71 and the lower mold 72 have temperature measuring means 75A and 75B, respectively, and the upper mold 71 and the lower mold 72 are provided so that the temperature can be adjusted independently. And the heat insulating material 104 is provided in the attachment surface 72m with the press machine main body 103 of the lower mold | type 72. FIG. The heat insulating material 104 can prevent the heat of the lower mold 72 from being transmitted to the press machine main body 103, and can prevent the temperature decrease of the upper mold 71 and the lower mold 72.

  On the other hand, the press molding die 90 in the second molding step shown in FIG. 10 also includes an upper die (punch) 91 and a lower die (die) 92, as in the press molding die 70 in the first molding step. Molding is performed between the convex portion 91d of the mold 91 and the concave portion 92c of the lower mold 92, but the molding surface of the convex portion 91d is formed substantially perpendicularly and provided in substantially the same shape as the bottom portion 61 of the square molded product 60. Yes. In accordance with this, the concave portion 92c is also formed on a substantially vertical molding surface, and the intermediate molded product 50 is drawn by the convex portion 91d and the concave portion 92c to form the square shaped product 60. Similarly to the press molding die 70 in the first molding step, the upper die 91 and the lower die 92 incorporate a heater (not shown) and temperature measuring means 95A and 95B. The mold 92 is provided independently of the temperature. A heat insulating material 106 is provided on a mounting surface 92m of the lower die 92 with the press machine main body 105. The heat insulating material 106 can prevent the heat of the lower mold 92 from being transmitted to the press machine main body 105, and can prevent the temperature of the upper mold 91 and the lower mold 92 from being lowered.

[Press molding method for square-shaped molded products]
And in the press molding method of 2nd Embodiment, the 1st shaping | molding using the 1st heating process and the 2nd heating process using the heating apparatuses 20 and 80 comprised in this way, and the press-molding dies 70 and 90 is carried out. Through the steps of the first heating step, the first molding step, the second heating step, and the second heating step, the blank material 10 is subjected to drawing to produce a square molded product 60. .

[First heating step]
In the first heating step, the blank material 10 is set to a temperature lower than the heat resistant temperature of the foamed synthetic resin layer 13 and the temperature difference from the heat resistant temperature of the foamed synthetic resin layer 13 to more than 10 ° C and not more than 22 ° C. While heating, the temperature of the inner surface 10b is heated to 3 ° C. or higher than the temperature of the outer surface 10a. The temperature difference between the outer surface 10a and the inner surface 10b is desirably 12 ° C. or less.
Specifically, as shown in FIG. 2, each heat transfer plate 21, 22 of the heating device 20 is heated by separate heating means 23, 24, and between these pair of heat transfer plates 21, 22. By placing the blank material 10 and sandwiching the outer surface 10a and the inner surface 10b between the pair of heat transfer plates 21 and 22, the heating of the outer surface 10a and the inner surface 10b of the blank material 10 is performed via the heat transfer plates 21 and 22, respectively. Do.

[First molding process]
In the first forming step, the blank material 10 heated in the first heating step is subjected to drawing using a press mold 70, and the drawing depth shallower than the final drawing depth (for example, 1/2 or more 3/4). An intermediate molded product 50 having the following drawing depth) is molded.
At this time, each heater (not shown) provided in the upper die 71 and the lower die 72 is heated before the blank material 10 is formed, and the temperature of the upper die 71 and the lower die 72 is set to be higher than the temperature of the blank material 10. Is heated to a low temperature within the range of 5 ° C. or more and 20 ° C. or less, and heated at that temperature. Thus, since the upper mold | type 71 and the lower mold | type 72 are previously heated by the temperature close | similar to the temperature of the blank material 10 heated at the 1st heating process, the temperature fall at the time of shaping | molding of the blank material 10 can be prevented. Further, warm forming can be performed while maintaining the temperature difference between the outer surface 10a and the inner surface 10b of the blank 10.

When the upper mold 71 is lowered in this warmed state, the convex portion 71d engages with the concave portion 72c while sandwiching the blank material 10 between the concave portion 72c of the lower mold 72, and at that time, the blank 71 The material 10 is bent, and the intermediate molded product 50 is formed. The intermediate molded product 50 has a smaller depth than the square molded product 60, and as shown in FIG. 7, the intermediate molded product 50 is formed in a tapered shape so that the side surface 53 extends toward the upper opening end. In addition, the radius of curvature of the corner 52 is formed large.
After the intermediate molded product 50 is molded, the intermediate molded product 50 is removed from the press molding die 70, and the second heating step is performed.

[Second heating step]
In the second heating step, similarly to the first heating step, the intermediate molded product 50 is set at a temperature lower than the heat resistant temperature of the foamed synthetic resin layer 13 and the temperature difference between the heat resistant temperature of the foamed synthetic resin layer 13 is 10 ° C. In addition to heating to a temperature exceeding 22 ° C., the temperature of the inner surface 50b is heated to a temperature higher by 3 ° C. than the temperature of the outer surface 50a. The temperature difference between the outer surface 50a and the inner surface 50b is desirably 12 ° C. or less.
Specifically, as shown in FIG. 9, each heat transfer plate 81, 82 of the heating device 80 is heated by separate heating means 83, 84, and between the pair of heat transfer plates 81, 82. The intermediate molded product 50 is arranged, and the outer surface 50a and the inner surface 50b are sandwiched between the pair of heat transfer plates 81 and 82, whereby the outer surface 50a and the inner surface 50b of the intermediate molded product 50 are respectively interposed via the heat transfer plates 81 and 82. Heat.

[Second molding process]
Finally, in the second molding step, the intermediate molded product 50 heated in the second heating step is subjected to drawing processing by the press molding die 90 shown in FIG.
In this second molding step, the intermediate molded product 50 is drawn from the bottom 51 of the intermediate molded product 50 so as to be sandwiched between the convex portion 91d of the upper die 91 and the concave portion 92c of the lower die 92. Processing is performed until the side surface portion 53 has an angle close to approximately 90 °, and the corner portion 52 is formed with a larger curvature than in the first molding step.

  At this time, before the start of molding, each heater (not shown) provided in the upper mold 91 and the lower mold 92 is heated, and the temperature of the upper mold 91 and the lower mold 92 is 5 ° C. higher than the temperature of the intermediate molded product 50. It is heated to a low temperature in the range of 20 ° C. or lower and heated at that temperature. Thus, since the upper mold 91 and the lower mold 92 are preheated to a temperature close to the temperature of the intermediate molded product 50 heated in the second heating step, the temperature drop during molding can be prevented, and the outer surface 50a. Can be warm-formed while maintaining the temperature difference between the inner surface 50b and the inner surface 50b.

In the second molding step, it is preferable to hold at the bottom dead center of the press mold 90 for 20 seconds or more during molding. By securing this holding time, the shape can be stabilized and deeper processing can be performed. If the holding time is less than 20 seconds, when the aperture depth is increased, the spring back becomes large and it is difficult to stabilize the shape. It is inefficient that the holding time is too long.
And the square shape molded product (final molded product) 60 shown in FIG. 7 is shape | molded by this 2nd shaping | molding process.

  As described above, according to the press molding method of the second embodiment, the first square forming process 60 is divided into the first molding process and the second molding process. After forming a shallow intermediate molded product 50 and subjecting the intermediate molded product 50 to a heat treatment process to remove processing distortion, the square molded product 60 can be molded in the second molding process. For this reason, it is possible to avoid the occurrence of cracks and wrinkles that are likely to occur when performing deep drawing continuously at a time, and to form a deeper three-dimensional molded product (square shaped product 60). Moreover, also when processing by dividing into a 1st shaping | molding process and a 2nd shaping | molding process in this way, before each shaping | molding process, the outer surface 10a and the inner surface 10b of the blank material 10, or the outer surface 50a and inner surface of the intermediate molded product 50 By providing a temperature difference to 50b and heating, a difference in deformability is provided between the outer surface and the inner surface, so that the formability of the blank material 10 (intermediate molded product 50) can be improved, and stable warm forming It can be performed. Therefore, a deeply molded square shaped product 60 can be manufactured while preventing generation of wrinkles and the like and obtaining good appearance characteristics.

In addition, this invention is not limited to the thing of the structure of the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, in the above embodiment, a far infrared heater is used as the heating unit, but the heating unit is not limited to this, and a halogen heater, a ceramic heater, or the like can be used.
Further, the configurations of the upper mold and the lower mold of the press mold and the punch and the die are not limited to the above-described configurations. For example, in the press molding die 30 shown in FIG. 3, the punch 33 may be disposed on the upper side and the die 31 may be disposed on the lower side so that the top and bottom are reversed.

As the blank material, an aluminum resin composite laminate having a tensile strength of 40 MPa, a proof stress of 25 MPa, an elongation of 17.2%, and a thickness of 3.5 mm is used. As a result, a rectangular tube-drawn container (a square molded product) having a bottom surface of 98 mm × 170 mm (bottom area of 16660 mm ² ) and a depth of 30 mm was manufactured. The outer surface side aluminum plate material has a tensile strength of 190 MPa and a proof stress of 140 MPa formed from a H22 tempered material of 5000 series alloy through general semi-continuous casting, hot rolling and cold rolling (including intermediate annealing). Using a plate material having a thickness of 16% and a thickness of 0.35 mm, the inner surface side aluminum plate material has a tensile strength of 120 MPa and a proof stress formed from a H24 tempered material of 1000 series alloy in the same manner as the outer surface side aluminum plate material. Was a plate material having a thickness of 0.15 mm and an elongation of 27%. For the foamed synthetic resin layer, polypropylene (melting point: 170 ° C., heat resistant temperature: 140 ° C.) was selected, and the expansion ratio was 2.5 times. The heat resistant temperature is, for example, a temperature at which the function of the resin product can be maintained without being deformed or altered in a state where no external force is applied. The deflection temperature under load of polypropylene is 77 ° C. In addition, an adhesive mainly composed of polypropylene was used as the adhesive. As for the mechanical properties of the blank material, a No. 5 test piece of JIS-Z2241 was prepared and subjected to a tensile test, and the tensile strength, 0.2% proof stress and elongation were measured.

In this embodiment, as shown in FIG. 2, the blank material 10 is sandwiched between a pair of preheated heat transfer plates 21 and 22, and the blank material 10 is heated to the “heating blank temperature” in Table 1. Then, the blank material 10 was installed in the press molding die 30 (FIG. 3). The heat transfer plates 21 and 22 were heated by using “far-infrared” heaters or “halogen” heaters as the heating means 23 and 24 as described in “Heating method” in Table 1.
In the molding step, the blank material 10 is drawn between the die 31 and the punch 33 using the press molding die 30 preliminarily heated to the “die temperature” shown in Table 1, and shown in FIG. Such a rectangular tube squeezed container (square shaped product) was molded. "Mold temperature" is arranged so that the tip of the thermocouple is arranged in the range from the inner surface of the corner to the outside of 10 mm at the four corners of the forming corner hole 31h of the die 31, This is a value obtained by measuring the temperature at that position. The “molding start blank temperature” is a state in which the blank material 10 is placed on the blank holder 32 and the outer periphery of the blank material 10 is sandwiched between the blank holder 32 and the die 31. It is the value which measured the temperature of the center part of the outer surface 10a of the blank material 10 with the radiation thermometer immediately before. Then, after measuring the temperature of the outer surface 10 a of the blank material 10, the blank material 10 was immediately moved downward, and the blank material 10 was drawn between the die 31 and the punch 33.

The appearance of the rectangular tube-drawn container thus obtained was observed, and the presence or absence of “cracking”, “wrinkle”, “skin roughness”, and “resin leakage” was evaluated.
For each evaluation, the appearance is “cracked”, “wrinkle”, “visually visible (white light only on the ceiling of the measurement room), visual inspection with a white light over the hand, and inspection with a 10x optical lens or more. "◎" indicates that no "rough skin" or "resin leakage" is observed, "○" indicates that it cannot be visually observed but can be confirmed with an optical lens of 10 times or more, and cannot be confirmed visually, but is confirmed with an optical lens of less than 10 times The case where it was possible to make it “△” and the case where it could be confirmed visually was made “X”.
These evaluation results are shown in Table 2.

  As can be seen from Table 2, no. Nos. 1 to 7 show almost good molding with almost no cracks, wrinkles, rough skin, and resin leakage. In contrast, No. of the comparative example. In 8-12, generation | occurrence | production of any one of a crack, a wrinkle, rough skin, and resin leakage is recognized, and it turns out that sufficient moldability is not acquired and three-dimensional shaping | molding by drawing is difficult.

10 Aluminum resin composite laminate (blank material)
11, 12 Aluminum plate material 13 Foamed synthetic resin layer 20 Heating device 21, 22 Heat transfer plates 23, 24 Heating means 25A, 25B Temperature measuring means 30 Press molding die 31 Die 32 Blank holder 33 Punch 35A, 35B Temperature measuring means 50 Intermediate Molded product (blank material)
60 Square molding 70 Press molding 71 Upper mold 72 Lower mold 75A, 75B Temperature measuring means 80 Heating means 81, 82 Heat transfer plate 83, 84 Heating means 90 Press molding die 91 Upper mold 92 Lower mold 95A, 95B Temperature measuring means 101, 103, 105 Press body 102, 104, 106

Claims (6)

A press molding method for drawing a blank material made of an aluminum resin composite laminate in which an aluminum plate material is bonded to both surfaces of a foamed synthetic resin layer into a rectangular rectangular shaped product with a bottom,
A heating step of heating the blank material;
A molding step of drawing the heated blank material using a press mold including a punch and a die, and
In the heating step, the blank material is heated to a temperature lower than the heat resistant temperature of the foamed synthetic resin layer and a temperature difference from the heat resistant temperature of the foamed synthetic resin layer to more than 10 ° C and not more than 22 ° C. In addition, the temperature of the inner surface of the blank material to be the concave surface of the square-shaped molded product is heated to a temperature higher by 3 ° C. or more than the temperature of the outer surface of the blank-shaped molded product to be the convex surface. A method for press-molding an aluminum resin composite laminate, characterized by comprising: In the molding step,
2. The press molding method for an aluminum resin composite laminate according to claim 1, wherein the temperature of the die is heated to a temperature lower than the temperature of the blank material within a range of 5 ° C. or more and 20 ° C. or less. . The heating step is performed using a pair of heat transfer plates,
Each heat transfer plate of the pair of heat transfer plates is heated by separate heating means,
The heating of each of the outer surface and the inner surface of the blank material is performed via each heat transfer plate by sandwiching the outer surface and the inner surface of the blank material between the pair of heat transfer plates. 3. A press molding method for an aluminum resin composite laminate according to 1 or 2.   The said heat-transfer board is formed with the aluminum material, The press molding method of the aluminum resin composite laminated board of Claim 3 characterized by the above-mentioned.   The said heating means is a far-infrared heater, The press molding method of the aluminum resin composite laminated sheet of Claim 3 or 4 characterized by the above-mentioned.   The aluminum resin composite laminate having a foaming ratio of the foamed synthetic resin layer of 1.5 to 10 times and a plate thickness of 1 to 10 mm is used as the blank material. The press molding method of the aluminum resin composite laminated sheet as described in any one of 1 to 5.

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