JP6715091B2 - Method for punching aluminum resin composite laminate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a punching method for processing a hole in an aluminum resin composite laminated plate formed by laminating an aluminum plate and a foamed synthetic resin layer.

In recent years, weight reduction of materials has been a major issue in plate-shaped members that have been used for various purposes. Not only in the field of automobiles, but also in railway vehicles, aircraft, ships and other transportation equipment, home appliances, IT-related members, and houses. It is required to reduce the weight of even the outer and inner wall materials of buildings. As an example, in the automobile field, 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 is under study. Furthermore, depending on the application, it is often required not only to be lightweight, but also to have additional properties such as vibration damping, sound insulation, and heat insulation. Two aluminum sheets are used as one of the plate materials to meet such requirements. It has been proposed to use an aluminum resin composite laminate in which a synthetic resin layer is sandwiched between the plates.

As such an aluminum resin composite laminated plate, 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 a sound absorbing panel in which a plurality of holes penetrating in the thickness direction are formed in a panel in which aluminum alloy plates (metal plates) are laminated on both sides of a foamed resin composed of closed cells. .. The patent document 2 describes that the holes of the sound absorbing panel are formed by penetrating a hole forming means such as a drill, a hole punch, a needle, a nail or a protrusion into the foamed resin of the panel and the aluminum alloy plate. ing. Further, in Patent Document 2, a panel is inserted between two rolls, a first roll having a needle on the surface and a second roll having a recess corresponding to the needle on the surface, and the needle is pierced into the panel. To form a hole by pressing, or press and sandwich the panel with two press plates, a first press plate having a needle on the surface and a second press plate having a concave portion corresponding to the needle on the surface. The method of forming the holes is illustrated.

International Publication No. 2010/029955 Patent No. 5626995

However, when the aluminum resin composite laminated plate is processed by the hole processing method as described in Patent Document 2, a dent (sag) that occurs in the periphery where the hole is processed and a foam synthetic resin layer that is the core material are formed. It is not possible to prevent burrs (whiskers) on the cut surface and push pits and the like caused by scraps, and it is easy to cause appearance defects. In particular, in the case of composite laminated plates used for vehicle members, it is possible to handle holes of various sizes from small diameter to large diameter, as well as holes of various shapes such as circular holes, square holes, and long holes, Improvement is desired because it is required to prevent the cut surface from being depressed or crushed around the hole and to prevent protrusions such as burrs and burrs.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for punching an aluminum resin composite laminated plate capable of suppressing appearance defects such as sagging and burrs.

The hole punching method for an aluminum resin composite laminate according to the present invention is such that an outer peripheral portion of a blank plate material of an aluminum resin composite laminate obtained by laminating aluminum plate materials on both sides of a foam synthetic resin layer is sandwiched between a die and a blank holder. In the state where a pressing load is applied, a punching step is performed in which a punch is penetrated in the thickness direction of the blank plate material to form a hole shape, and the foaming synthetic resin layer of the blank plate material has a foaming ratio of 1 5 times or more and 10 times or less, and a plate thickness of 1 mm or more and 10 mm or less, and a tensile strength of a first aluminum plate material arranged on one surface of the aluminum plate materials laminated on both surfaces of the foamed synthetic resin layer. In the punching step, the punching is performed at room temperature from the first aluminum plate material side to the second aluminum plate material side of the blank plate material at a normal temperature. Through.

Since the aluminum resin composite laminated plate is provided with the foamed synthetic resin layer which is the core material, it is very difficult to perform the punching process as compared with the case of processing the metal plate formed of a single metal. That is, since the expanded synthetic resin layer that is the core material is soft and the tensile strengths of the aluminum plate materials (first aluminum plate material and second aluminum plate material) arranged on both sides and the expanded synthetic resin layer are different, during the punching process Due to the pressing force applied by the punch, the foamed synthetic resin layer is easily deformed/reduced before the surface aluminum plate material is cut, and the aluminum plate material on the surface is susceptible to sagging or burr. is there.
In this respect, in the punching method of the present invention, among the aluminum plate materials arranged on both sides of the blank plate material, punching is performed from the first aluminum plate material side having a small tensile strength to the second aluminum plate material side having a large tensile strength. The punching is performed by penetrating it, and by punching from the side of the first aluminum plate having a smaller tensile strength, which is closer to the tensile strength of the foamed synthetic resin layer, it is possible to prevent plastic deformation of the foamed synthetic resin layer. The aluminum plate material, the foamed synthetic resin layer, and the second aluminum plate material can be brought close to each other in cutting timing. Therefore, appearance defects such as sagging and deformation that occur on the surface of the first aluminum plate on the processing start surface side and burrs that occur on the surface of the second aluminum plate on the processing end surface side can be suppressed, and a blank plate material made of an aluminum resin composite laminate The workability of can be improved.

In the punching method of the aluminum resin composite laminate of the present invention, the punching step may be performed in a state in which the pressing load is applied at 0.2 kN or more and 15 kN or less.

By sandwiching the outer peripheral portion of the blank plate material between the die and the blank holder and applying a pressing load of 0.2 kN or more and 15 kN or less, the blank plate material can be prevented from being displaced and sagging or burrs are generated. Since it can be further suppressed, it is possible to satisfactorily perform punching of small-diameter size holes and various shapes other than circular holes.
If the pressing load is less than 0.2 kN, the fixing force of the blank plate material becomes insufficient, and the position of the blank plate material may shift when the punch abuts. Moreover, when the maximum load of the pressing load exceeds 15 kN, there is a possibility that the sandwiching portion of the blank plate material may be dented or deformed.

In the method of punching an aluminum resin composite laminate according to the present invention, it is preferable that a low hardness urethane having a Shore hardness of A15 or more and A45 or less is provided on the fixing surface of the blank holder facing the die.

By providing low-hardness urethane on the fixing surface of the blank holder, it is possible to further prevent the blank plate material from being displaced, and to prevent scratches, dents, or the like from occurring in the sandwiched portion of the blank plate material.
If the Shore hardness is less than A15, the fixing force of the blank plate material becomes insufficient, and the blank plate material may be displaced. If the Shore hardness exceeds A45, the low hardness urethane may be too hard and may cause scratches, dents or the like on the blank plate material.

In the punching method for an aluminum resin composite laminate according to the present invention, a clearance on one side between the punch and the die hole of the die may be provided within a range of 0.5 mm or more and 1.5 mm or less.

If the one-side clearance between the punch and the die hole is less than 0.5 mm, the one-side clearance is too small, and secondary shear planes, burrs, sags, and deformations are likely to occur. On the other hand, even when the clearance on one side exceeds 1.5 mm, the clearance on one side is too large, so that sagging, burrs, and deformation are likely to occur.

According to the present invention, it is possible to prevent appearance defects such as sagging and burrs even when processing a hole shape in an aluminum resin composite laminate.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating a punching method for an aluminum resin composite laminate according to an embodiment of the present invention, showing a state in which a blank plate material is installed in a press molding die. FIG. 2 is a cross-sectional view of the press-molding die shown in FIG. 1, illustrating a state where the punch is moved from the state of FIG. 1 and a blank plate material is punched with the punch.

Hereinafter, an embodiment of a punching method for an aluminum resin composite laminate according to the present invention will be described.
The blank board material 10 made of an aluminum resin composite laminated board used in the present invention has aluminum foam materials 11 and 12 having different tensile strengths laminated on both surfaces of a foam synthetic resin layer 13 as schematically shown in FIG. It has a different structure. In the following, the aluminum plate member arranged on one surface of the foamed synthetic resin layer 13 of the aluminum plate members 11 and 12 is the first aluminum plate member 11, and the aluminum plate member is arranged on the other surface and has a tensile strength higher than that of the first aluminum plate member 11. The aluminum plate having a small value is referred to as a second aluminum plate 12.

The foamed synthetic resin layer 13 constituting the blank plate material 10 has a foaming ratio of 1.5 to 10 times and a plate thickness t3 of 1 mm to 10 mm. If the expansion ratio of the expanded synthetic resin layer 13 is less than 1.5 times, it is insufficient in terms of vibration damping properties, sound insulation properties, and heat insulation properties. On the contrary, if it exceeds 10 times, a uniform and stable expansion state cannot be obtained, and a blank is obtained. When the plate material 10 is processed, defects such as cracks and wrinkles due to local deformation are caused. Further, when the plate thickness t3 of the foamed synthetic resin layer 13 is 1 mm or less, the performance such as the vibration damping property is insufficient, and the molding process of the blank plate material 10 becomes very difficult. When the plate thickness t3 of the foamed synthetic resin layer 13 exceeds 10 mm, the molding process is difficult and the appearance abnormality such as rough skin is likely to occur.

Specifically, the types of synthetic resin forming the foamed synthetic resin layer 13 are polyethylene resin (PE), polypropylene resin (PP), polystyrene resin (PS), AS resin, ABS resin, polyvinyl chloride resin (PVC). , Methacrylic resin (PMMA), polyethylene terephthalate resin (PET), or polycarbonate (PC).

The first aluminum plate material 11 has a tensile strength of 100 MPa or more and 200 MPa or less, a proof stress of 80 MPa or more and 180 MPa or less, and an elongation of 3% or more and 27% or less. For example, the first aluminum plate material 11 is made of copper (Cu). The content is 0.01% by mass or more and 0.03% by mass or less, and the balance is aluminum and unavoidable impurities. Specifically, 1000 series aluminum (1050 etc.) which is a part of Japanese Industrial Standard (JIS standard) is applicable.

The second aluminum plate material 12 has a tensile strength of 150 MPa or more and 610 MPa or less, a proof stress of 120 MPa or more and 500 MPa or less, an elongation of 2.5% or more and 18% or less, and a tensile strength of 10 MPa or more larger than that of the first aluminum plate material 11. To be taken. For example, the 2nd aluminum plate material 12 contains 1.5 mass% or more and 1.8 mass% or less of magnesium, 0.01 mass% or less of copper, and the balance consists of aluminum and unavoidable impurities. Specifically, a part of Japanese Industrial Standards, 5000 series aluminum (5151 etc.) is applicable.

The plate thickness t1 of the first aluminum plate member 11 is 0.1 mm or more and 0.3 mm or less, and the plate thickness t2 of the second aluminum plate member 12 is 0.25 mm or more and 0.5 mm or less. The plate thickness t1 is provided to be smaller than the plate thickness t2 of the second aluminum plate member 12. If the first aluminum plate member 11 and the second aluminum plate member 12 satisfy the above mechanical properties, The alloy component is not limited to this, depending on the shape of the desired three-dimensional molded product, the degree of processing of the details, the appearance property, the corrosion resistance, and other required properties, and the material temper is appropriately selected. sell.

As a whole of the blank plate material 10 made of an aluminum resin composite laminated plate formed by laminating both the aluminum plate materials 11 and 12 and the foamed synthetic resin layer 13 configured as described above, the tensile strength is 15 MPa or more and 150 MPa or less, and the proof stress is 10 MPa or more. 130 MPa or less and an elongation of 2.5% or more and 27% or less are good, and a stable pressed product can be molded.

And the blank board material 10 which consists of an aluminum resin composite laminated board is manufactured by preparing the foaming synthetic resin layer 13 and both aluminum board materials 11 and 12, respectively, and laminating|stacking these via an adhesive layer. It is preferable that the adhesive layer is made of a resin whose main component is the same as the material of the foamed synthetic resin layer 13 of the core material, in order to secure necessary adhesiveness. For example, when the foamed synthetic resin layer 13 serving as the core material is made of polypropylene, it is preferable that the adhesive layer is made of an adhesive or the like containing polypropylene as a main component. In this case, the adhesion between the aluminum plate materials 11 and 12 on both sides and the expanded synthetic resin layer 13 which is the core material is increased, and the aluminum plate materials 11 and 12 and the expanded synthetic resin layer 13 are formed during punching and subsequent use. Peeling at the interface can be suppressed.
Then, such an adhesive is applied to both surfaces of the foamed synthetic resin layer 13 or one surface of both aluminum plate members 11 and 12, and the foamed synthetic resin layer 13 is sandwiched between both aluminum plate members 11 and 12, and these are hot-pressed or By pressurizing and heating with a hot roll, the aluminum plate members 11 and 12 are integrally laminated on both surfaces of the foamed synthetic resin layer 13 with an adhesive layer interposed therebetween.

(Method of punching aluminum resin composite laminate)
Next, in order to perform the punching process on the blank plate material 10 of the aluminum resin composite laminated plate thus obtained, a pressing die 101 is used as shown in FIGS. 1 and 2, for example. The press die 101 has a die 21 having a die hole 22 having substantially the same shape as the hole to be formed, a blank holder 31 having a through hole 32 having substantially the same shape as the die hole 22, and a columnar shape for punching out the hole shape. The punch 41 is provided. In this embodiment, since the circular hole is punched out, all of the die hole 22, the through hole 32, and the punch 41 are circular. Further, the blank holder 31 of the pressing die 101 is equipped with a spring 35 for applying a pressing load to the outer peripheral portion of the blank plate material 10 sandwiched between the die 21 and the blank holder 31.

The spring 35 is provided with an initial load of 0.2 kN or more and a maximum load of 15 kN or less. When the outer peripheral portion of the blank plate material 10 is sandwiched by the spring 35 between the die 21 and the blank holder 31. In addition, a pressing load of 0.2 kN or more and 15 kN or less is applied to the outer peripheral portion of the blank plate material 10. Further, a low hardness urethane 33 having a Shore hardness of A15 or more and A45 or less is provided on the fixed surface of the blank holder 31 facing the die 21 to prevent displacement of the sandwiched blank plate material 10 and further to prevent the blank plate material 10 from being displaced. It is possible to prevent scratches and dents from being formed on the surface of the. When the Shore hardness of the low hardness urethane 33 is less than A15, the fixing force of the blank plate material 10 becomes insufficient, and the blank plate material 10 may be displaced. If the Shore hardness of the low hardness urethane 33 exceeds A45, the low hardness urethane 33 may be too hard and may cause scratches, dents, or the like on the blank plate material 10. The Shore hardness is a value measured using a Type A durometer of JIS-K6253.

Further, as shown in FIGS. 1 and 2, the one-side clearance c1 between the punch 41 and the die hole 22 of the die 21 is provided within a range of 0.5 mm or more and 1.5 mm or less. If the one-side clearance c1 between the punch 41 and the die hole 22 is less than 0.5 mm, the one-side clearance c1 is too small, so that secondary sheared surfaces, burrs, sags, and deformations are likely to occur. On the other hand, even when the one-side clearance c1 exceeds 1.5 mm, the one-side clearance c1 is too large, so that sagging, burrs, and deformation are likely to occur.

Then, in the punching method of the present embodiment, this punching die 101 is used to punch holes in the thickness direction of the blank plate 10 through a punching step described below.
(Punching process)
The punching process is performed at room temperature (25° C.). First, the blank plate material 10 is arranged on the die 21 of the pressing die 101 so as to overlap the second aluminum plate material 12. That is, of the aluminum plate materials 11 and 12 laminated on both surfaces of the foamed synthetic resin layer 13, the first aluminum plate material 11 having the smaller tensile strength is arranged toward the blank holder 31 on the processing start surface side, and the tensile strength is increased. The second aluminum plate member 12 having the larger size is arranged toward the die 21 on the processing end surface side. Then, after the blank plate material 10 is placed on the die 21, the blank holder 31 is moved down to hold the outer peripheral portion of the blank plate material 10 between the die 21 and the blank holder 31, as shown in FIG. To do. At this time, a pressing load of 0.2 kN or more and 15 kN or less is applied to the outer peripheral portion of the blank plate material 10 by the spring 35.

Next, as shown in FIG. 2, the punch 41 is moved downward in a state where the outer peripheral portion of the blank plate material 10 is sandwiched and a pressing load is applied, and the punch 41 is moved from the first aluminum plate material 11 side to the second aluminum plate material 12 side. The hole shape 15 is punched out by penetrating to the side. At this time, of the aluminum plate members 11 and 12 arranged on both sides, the first aluminum plate member 11 having a tensile strength close to the tensile strength of the expanded synthetic resin layer 13, which is the core material, is first brought into contact with the punch 41. Since the punch 41 is penetrated from the side of the first aluminum plate 11 having a small tensile strength to the side of the second aluminum plate 12 having a large tensile strength, it is difficult to cause plastic deformation in the synthetic foam resin layer 13, The cutting timings of the 1st aluminum plate 11, the foamed synthetic resin layer 13, and the 2nd aluminum plate 12 can be made close to each other. Therefore, it is possible to suppress appearance defects such as sagging and deformation that occur on the surface of the first aluminum plate material 11 on the processing start surface side and burrs that occur on the surface of the second aluminum plate material 12 on the processing end surface side, and the aluminum resin composite laminate plate is used. The workability of the blank plate material 10 can be improved.

In addition, when the punch 41 is penetrated from the second aluminum plate material 12 side to the first aluminum plate material 11 side, the second aluminum plate material 12 having a large tensile strength is hard to be deformed, so that the second aluminum plate material 12 is cut. Before being punched, the foam synthetic resin layer 13 is likely to be plastically deformed by the punch 41 through the second aluminum plate material 12 by being deformed/reduced, and the second aluminum plate material 12 and the first aluminum plate material 11 are affected by this influence. Therefore, the surface may be sagged or burred.

Further, in the hole punching process, the blank plate member 10 can be prevented from being displaced by sandwiching the outer peripheral portion of the blank plate member 10 between the die 21 and the blank holder 31, so that the occurrence of sagging, burrs, and the like can be further suppressed. .. Therefore, it is possible to satisfactorily perform punching of small-diameter holes and various shapes other than circular holes.
If the pressing load applied by the blank holder 31 is less than 0.2 kN, the fixing force of the blank plate material 10 becomes insufficient, and the position of the blank plate material 10 may be displaced when the punch 41 abuts. Moreover, when the maximum load of the pressing load of the blank holder 31 exceeds 15 kN, there is a possibility that the sandwiching portion of the blank plate material 10 may be dented or deformed.

The present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the spirit of the present invention.

An aluminum resin composite laminated plate is manufactured using the foamed synthetic resin layer, the first aluminum plate material, and the second aluminum plate material shown in Table 1, and a circular hole having a diameter of 10 mm is punched in a blank plate material formed of this aluminum resin composite laminated plate. processed. In addition, "PP" of a resin kind of a foaming synthetic resin layer represents polypropylene, "PE" represents polyethylene, and "PC" represents polycarbonate. The punching process for each blank plate material was performed under the conditions shown in Table 1. The tensile strength of the first aluminum plate and the second aluminum plate was measured by making a No. 5 test piece of JIS-Z2241 and performing a tensile test.

Then, each blank plate material after the hole punching step was observed, and evaluation items shown in Table 2 (dimensional accuracy, dents around the hole, hole deformation, sag, burr, warpage, secondary sheared surface) were evaluated. “Dimensional accuracy” is “◎” when the dimensional tolerance is within ±10 μm, “◯” when the dimensional tolerance is not within ±10 μm but within ±50 μm, and the dimensional tolerance is within ±50 μm When the value was within ±100 μm, it was evaluated as “Δ”, and when the dimensional tolerance was out of ±100 μm, it was evaluated as “x”. In addition, "dent around the hole", "deformation of the hole", "sag", "burr", "warp" is "◎" when it cannot be confirmed by visual inspection by holding the halogen light (under the halogen light). , When it can be visually confirmed under a halogen light but not visually under a white light, it is marked as “○”. Furthermore, it can be visually confirmed under a white light but cannot be visually confirmed under normal light, or only slightly visible. The case was designated as “Δ”, and the case where it could be clearly confirmed even under normal light was designated as “x”. In addition, when all of these evaluation items are "○" or more and there are three or more "◎", all of the evaluation items are "○" or more and "◎" is 1 If the number is two or more, it is "B", all the evaluation items are "△" or less, and if the number of "△" is three or more is "C", all the evaluation items are "△" or less, In addition, when the number of “Δ” is one or two, the determination is made as “D”.

As can be seen from Table 2, No. In Nos. 1 to 11, there is no appearance defect and it is possible to process a hole shape having excellent dimensional accuracy, and good workability is exhibited. On the other hand, in Comparative Example No. In Nos. 12 to 20, occurrence of any of depressions around the holes, deformation of the holes, sagging, burrs, and warpage was observed, and sufficient dimensional accuracy could not be obtained, resulting in deterioration of workability.

10 Blank Plate Material of Aluminum Resin Composite Laminated Plate 11 First Aluminum Plate Material 12 Second Aluminum Plate Material 13 Foam Synthetic Resin Layer 15 Hole Shape 101 Press Mold 21 Die 22 Die Hole 31 Blank Holder 32 Through Hole 33 Low Hardness Urethane 35 Spring 41 punch

Claims (4)

The thickness of the blank plate material in a state in which the outer peripheral part of the blank plate material of the aluminum resin composite laminated plate in which the aluminum plate materials are laminated on both sides of the foamed synthetic resin layer is sandwiched between the die and the blank holder and a pressing load is applied. Has a hole punching process that penetrates the punch in the direction to process the hole shape,
Among the aluminum plate materials laminated on both sides of the foamed synthetic resin layer, the foamed synthetic resin layer of the blank plate material has a foaming ratio of 1.5 times or more and 10 times or less and a plate thickness of 1 mm or more and 10 mm or less. The tensile strength of the first aluminum plate material arranged on one surface is made smaller than the tensile strength of the second aluminum plate material arranged on the other surface,
The punching process for an aluminum resin composite laminate sheet, wherein the punching step is performed at room temperature by penetrating the punch from the side of the first aluminum plate of the blank plate to the side of the second aluminum plate. The method for punching an aluminum resin composite laminate according to claim 1, wherein the punching step is performed in a state where the pressing load is applied at 0.2 kN or more and 15 kN or less. 3. The punching method for an aluminum resin composite laminate according to claim 1, wherein a low hardness urethane having a Shore hardness of A15 or more and A45 or less is provided on a fixed surface of the blank holder facing the die. .. 4. The one-side clearance between the punch and the die hole of the die is provided within a range of 0.5 mm or more and 1.5 mm or less, according to claim 1. A method for punching an aluminum resin composite laminate.