JP2019031054A - Method for producing composite molded body of resin and metal member - Google Patents

Abstract

To provide a technique capable of enhancing a bonding strength between a resin and a metal member only by adding a simple configuration in a manufacturing process.SOLUTION: A method for producing a composite molded body of a resin and a metal member disclosed in this specification includes a step of irradiating a pulse laser through a liquid formed over a surface of a metal member on which a resin is placed, and a step of joining the resin to the surface. According to this method for producing a composite molded article, it is possible to increase a bonding strength between the resin and the metal member by adding a simple structure (forming the liquid over the metal surface when irradiating the laser) in a manufacturing process.SELECTED DRAWING: Figure 2

Description

  This specification discloses the technique regarding manufacture of the composite molded object of resin and a metal member.

  A composite molded body of a resin and a metal member is used in various applications such as a vehicle cooler. Patent Documents 1 and 2 describe techniques related to the manufacture of a composite molded body of a resin and a metal member. In Patent Document 1, high-density energy such as laser light is applied to the surface of a metal member that serves as a resin bonding surface. In patent document 2, short pulse light is irradiated to the surface of the metal member used as the joint surface of resin.

JP 2013-71312 A JP2015-71258A

  By the way, in such a composite molded body, it is preferable to increase the bonding strength between the resin and the metal member in order to improve the shear strength, tensile strength, and sealing performance at the bonding surface between the resin and the metal member. Therefore, the present specification provides a technique capable of increasing the bonding strength between the resin and the metal member only by adding a simple configuration in the manufacturing process.

  The method for producing a composite molded body of a resin and a metal member disclosed in the present specification includes a step of applying a liquid to a surface of a metal member on which a resin is disposed and irradiating a pulse laser through the liquid; Joining.

  According to the method of manufacturing a composite molded body of this aspect, a liquid is applied to the surface of the metal member on which the resin is disposed, and the pulse laser is irradiated through the liquid. Since the surface of the metal member is rapidly cooled by this liquid after the pulse laser irradiation, nanostructures can be formed on the surface of the metal member. Further, since a pulse wave from the liquid hits the surface of the metal member by irradiating the pulse laser through the liquid, a porous structure (porous structure) can be formed on the surface of the metal member. As a result, according to the method for manufacturing a composite molded body of the present embodiment, by adding a simple configuration (stretching a liquid on the metal surface when irradiating a laser) in the manufacturing process, the resin and the metal member Bonding strength can be increased.

It is sectional drawing which shows schematic structure of a composite molded object. It is a flowchart which shows the manufacturing method of a composite molded object. It is a figure explaining step S10. It is a figure explaining step S12. It is a figure explaining step S12. It is a table | surface showing the result of the physical-property evaluation of a composite molded object. It is a figure explaining the metal member for a test, and the roughening range of a pulse laser. It is a figure explaining the metal member for a test, and the roughening range of a pulse laser. It is a figure explaining cooling of sample # 2. It is a figure explaining cooling of sample # 2. It is a figure explaining the resin member for a test. It is a figure explaining joining strength evaluation. It is a figure explaining sealing performance evaluation.

  (Configuration of Composite Molded Body) FIG. 1 is a sectional view showing a schematic configuration of a composite molded body 1 as an example. The composite molded body 1 is a material in which a metal member 10 and a resin member 20 are joined. The composite molded body 1 is used in various applications such as vehicle parts, vehicle-mounted products, electronic devices, and home appliances. For example, the composite molded body 1 is used in a part that requires sealing performance (sealing performance) such as a joined body of a cooling fin (metal member) and a mold resin (resin member) in an inverter of an electric vehicle. FIG. 1 schematically shows the fine structure of the surface 11 to which the resin member 20 of the metal member 10 is bonded.

  The metal member 10 has a plate shape having a first surface 11 and a second surface 12. The metal member 10 is made of aluminum (Al). The metal member 10 may be made of any material as long as a rough surface can be formed by a pulse laser.

  The resin member 20 is a plate-like member disposed on one surface of the metal member 10. The resin member 20 is bonded to the first surface 11 of the metal member 10. The resin member 20 is a member made of an epoxy resin. In addition, the resin member 20 can employ | adopt arbitrarily the combination of all the different materials of resin, such as a polymeric material and an elastomer which belong to the classification of a thermoplastic resin or a thermosetting resin.

  Of the metal member 10, the nanostructure 11 </ b> N and the porous layer 11 </ b> P are formed on the first surface 11 on which the resin member 20 is disposed. The nanostructure 11N includes a plurality of raised portions 101 formed by raising the first surface 11 of the metal member 10. Each ridge 101 is a fine ridge whose height from the first surface 11 is nanometer level. The porous layer 11P includes a plurality of pores 102 formed on the first surface 11 side of the metal member 10. Each pore 102 is a fine hole having a diameter of nanometer level.

  As shown in FIG. 1, the resin member 20 enters the gaps between the raised portions 101 of the metal member 10 and the pores 102 of the metal member 10. For this reason, the composite molded body 1 of the present embodiment has a high bonding strength between the resin member 20 and the metal member 10. Details thereof will be described later.

  (Method for Manufacturing Composite Molded Body) FIG. 2 is a flowchart showing a method for manufacturing the composite molded body 1. FIG. 3 is a diagram for explaining the processing in step S10. 4 and 5 are diagrams for explaining the processing in step S12.

  In step S10 of FIG. 2, the metal member 10 is prepared, and a liquid is stretched on the first surface 11 (resin arrangement surface) on which the resin member 20 is arranged in the metal member 10. Specifically, as shown in FIG. 3, the first surface 11 of the metal member 10 is directed upward in the vertical direction, and the cover glass 30 is placed thereon, and the first surface 11, the cover glass 30, Is filled with the liquid 40. 3 to 5 schematically show phenomena that occur on the surface 11 of the metal member 11 in order to help understanding. The distance between the first surface 11 of the metal member 10 and the cover glass 30 is, for example, 1 [mm], and the liquid does not leak from the edge of the cover glass 30 due to the surface tension of the liquid. Can stay in between.

  In this embodiment, water is used as the liquid 40, but other liquids (oils, molten salts, etc.) that can transmit a pulse laser may be used. In addition, it replaces with the cover glass 30, and other members which can permeate | transmit a pulse laser may be utilized, and the cover glass 30 may be abbreviate | omitted by surrounding the edge of the metal member 10 so that the liquid 40 may not leak.

  In step S <b> 12 of FIG. 2, the metal member 10 is irradiated with a pulse laser through the liquid 40. Specifically, as shown in FIG. 4, the pulse laser PL is irradiated from the upper side of the cover glass 30 to the metal member 10 through the liquid 40.

  By irradiation with the pulse laser PL, high energy is input to the first surface 11 of the metal member 10 in a short time. Due to this high energy, the metal in the vicinity of the first surface 11 is locally melted violently, and the raised portion 101 and the metal splash 103 are generated. Here, as described above, the liquid 40 is stretched on the first surface 11. The melted metal is rapidly cooled by the liquid 40, and the raised portions 101 and the metal splashes 103 are solidified while maintaining the shape at the time of melting.

  Further, the pulse laser PL is irradiated through the liquid 40. For this reason, the shock wave SW from the liquid 40 generated when the high energy of the pulse laser PL passes through the liquid 40 strikes the first surface 11 of the metal member 10. By this shock wave SW, the metal melted or softened by the high energy of the pulse laser PL becomes porous, and the pores 102 (see FIG. 1) are formed.

  As described above, the nanostructure 11N and the porous layer 11P are formed on the first surface 11 of the metal member 10 by step S12 (irradiation of the pulse laser PL through the liquid 40) as shown in FIG. And can be formed.

  In step S14 of FIG. 2, the resin member 20 is bonded to the first surface 11 (resin arrangement surface) on which the nanostructure 11N and the porous layer 11P are formed. Specifically, a plate-like resin member 20 is prepared, the resin member 20 is placed on the preheated first surface 11 of the metal member 10, and a predetermined molding pressure is applied and held for a predetermined time. The pressure and time can be arbitrarily determined. Then, the metal member 10 and the resin member 20 are joined to each other by heating the metal member 10 and the resin member 20 at a predetermined temperature in a constant temperature bath for a predetermined time. The temperature and time can be arbitrarily determined. Note that various methods can be adopted as a method of joining the resin member 20. For example, the resin member 20 may be injection-molded with respect to the metal member 10.

  (Physical property evaluation of composite molded body: preparation of sample) FIG. 6 is a table showing the results of physical property evaluation of the composite molded body 1 as an example. In FIG. 6, the bonding strength between the metal member 10 and the resin member 20 and the sealing performance were evaluated for the samples # 1 to # 3 of the three composite molded bodies 1 produced by different manufacturing methods. Sample # 1 is a sample produced by the manufacturing method described in this example. Samples # 2 and # 3 are comparative examples. For the bonding strength, the shear strength at the bonding surface between the metal member 10 and the resin member 20 and the tensile strength at the bonding surface between the metal member 10 and the resin member 20 were evaluated.

  7 and 8 are diagrams for explaining the test metal member 10t and the roughening range 11A of the pulse laser PL. In each sample # 1 to # 3, a flat aluminum substrate 10t having a circular hole HO penetrating the first surface 11 and the second surface 12 in the center was used as a test metal member. . The width W of the aluminum substrate 10t was 50 mm, the depth D was 50 mm, and the height H was 3 mm (FIG. 7). Further, the diameter L1 of the hole HO was 8 mm, and the range of the diameter L2 (18 mm) around the hole HO was a roughening range 11A of the pulse laser PL (FIG. 8).

In each sample # 1 to # 3, the roughening range 11A of the first surface 11 of the aluminum substrate 10t was irradiated with the pulse laser PL concentrically as shown in FIG. As the equipment used, SUNX LP-MA05 manufactured by Panasonic Corporation was used. The roughening conditions were a rated output of 80 W, a pulse width of 150 nm, and an energy density of 26.7 J / cm ² . At this time, the sample # 1 was irradiated with the pulse laser PL through the liquid 40 as described in steps S10 and S12 of FIG. The liquid 40 is water. On the other hand, in samples # 2 and # 3, the pulse laser PL was irradiated without passing through the liquid 40.

  In sample # 1, since the pulse laser PL was irradiated through the liquid 40, as described in step S12 of FIG. 2, the roughened range 11A of the aluminum substrate 10t includes the nanostructure 11N including the raised portions 101, pores, and the like. A porous layer 11P including 102 is formed.

  9 and 10 are diagrams for explaining the cooling of the sample # 2. In sample # 2, air cooling using the air nozzle 2 was performed during the pulse laser PL irradiation. The air cooling was performed under the condition that the distance L3 between the air discharge port 21 of the air nozzle 2 and the aluminum substrate 10t was 15 mm, and the angle θ between the axis O of the air nozzle 2 and the aluminum substrate 10t was 45 degrees.

  In sample # 2, the pulse laser PL was irradiated with air cooling. For this reason, as shown in FIG. 10, the raised portion 101 and the metal splash 103 generated on the first surface 11 (roughening range 11A) of the aluminum substrate 10t are rapidly cooled, and the raised portion 101 and the metal splash 103 are Solidify while maintaining the melted shape. As a result, also in the sample # 2, the nanostructure 11N composed of the raised portions 101 is formed as in the sample # 1. On the other hand, in sample # 2, there is no liquid 40 serving as a shock wave medium. For this reason, the porous layer 11P including the pores 102 is not formed in the sample # 2.

  In sample # 3, the pulse laser PL was irradiated without passing through the liquid 40 and without air cooling. For this reason, neither the nanostructure 11N including the raised portion 101 nor the porous layer 11P including the pores 102 is formed in the sample # 3.

  FIG. 11 is a diagram illustrating a test resin member 20t. The aluminum substrate 10t of each sample # 1 to # 3 in which the roughening range 11A was processed was put in a dedicated mold and preheated at 175 degrees for 3.5 minutes. A circular epoxy resin 20t (test resin member 20t) covering the roughening range 11A is placed on each of the pre-heated aluminum substrates 10t of the samples # 1 to # 3 at a molding pressure of 7 Mpa. Hold for 2 minutes. After cooling, each sample # 1 to # 3 was taken out from the dedicated mold and heated at 180 degrees for 1 hour using a thermostatic bath to join the epoxy resin 20t to the aluminum substrate 10t.

  (Physical property evaluation of composite molded article: Evaluation) FIG. 12 is a diagram for explaining a method for evaluating the bonding strength. In FIG. 12, the AA cross section of FIG. 11 is shown. First, the shear strength was measured for each sample # 1 to # 3 prepared as described above. Specifically, a load of 5 mm / min is applied until the interface peeling of the bonding surface JS occurs in the direction T1 parallel to the bonding surface JS between the aluminum substrate 10t and the epoxy resin 20t, or until the epoxy resin 20t breaks. By continuing to add, the tensile strength (Mpa) of the aluminum substrate 10t and the epoxy resin 20t was measured.

  The measured value of the shear strength (tensile strength) and the determination result of the shear strength are shown in “strength: shear strength” in FIG. Samples # 1 and # 2 had a tensile strength of 30 Mpa or more, and no interfacial peeling of the joint surface JS occurred. For this reason, the determination of samples # 1 and # 2 is determined as A. On the other hand, since sample # 3 had a tensile strength of 5 Mpa or less and interface peeling of the joint surface JS occurred, C was determined. In addition, the determination result in the table | surface of FIG. 6 shows that A determination is the best and C determination is the inferior.

  Next, the tensile strength was measured for each sample # 1 to # 3. Specifically, the load portion 3 is inserted from the hole HO of the aluminum substrate 10t, and the interface surface JS is peeled off in the direction T2 perpendicular to the bonding surface JS, or 5 mm until the epoxy resin 20t breaks. The tensile strength (Mpa) between the aluminum substrate 10t and the epoxy resin 20t was measured by continuing to apply a load per minute.

  The measured value of tensile strength (adhesive strength) and the determination result of tensile strength are shown in “strength: tensile strength” in FIG. In sample # 1, the tensile strength was 30 Mpa or more, and no interfacial peeling occurred on the joint surface JS. On the other hand, sample # 2 had a tensile strength of 10 Mpa, and interface peeling of the joint surface JS occurred. In sample # 3, the tensile strength was 5 Mpa or less, and interface peeling of the joint surface JS occurred.

FIG. 13 is a diagram for explaining seal performance evaluation. In FIG. 13, the AA cross section of FIG. 11 is shown. The sealing performance was measured for each sample # 1 to # 3. Specifically, the O-ring 4 is attached to the aluminum substrate 10t as shown in the figure, and helium (He) gas is filled from the hole HO of the aluminum substrate 10t. The amount of He leak leaked from the joint surface JS was measured with a He leak rate of 5.0 × 10 ⁻⁵ Pa · m ³ / s as a standard value.

  The measured value of the He leak amount and the determination result of the seal performance are shown in “seal performance” of FIG. Sample # 1 had a He leak amount of 1.10E-09, very little leak, and was judged as A. In sample # 2, the amount of He leak was 1.68E-08, the leak was small, and A was determined. Sample # 3 had a He leak amount of 1.06E-04, and was judged as C.

  As described above, Sample # 1 of the present invention prepared in accordance with the manufacturing method described with reference to FIG. 2 was able to obtain A judgment in all of shear strength, tensile strength, and seal performance. This is because the epoxy resin 20t (for the gap between the raised portions 101 of the nanostructure 11N and the inside of the pores 102 of the porous layer 11P formed on the aluminum substrate 10t (metal member 10). This is because the resin member 20) enters and the aluminum substrate 10t and the epoxy resin 20t are firmly bonded.

  On the other hand, Sample # 2 as a comparative example prepared by air cooling had A judgment on the shear strength and sealing performance, but B judgment on the tensile strength. This is because the nanostructure 11N formed on the aluminum substrate 10t increases the seal area between the aluminum substrate 10t and the epoxy resin 20t, but the aluminum substrate 10t does not have the porous layer 11P, and thus is perpendicular to the bonding surface JS. This is because a sufficient bonding strength in the direction T2 (FIG. 12) cannot be obtained.

  Sample # 3 as a comparative example in which neither water cooling nor air cooling was performed was C judgment in all of shear strength, tensile strength, and seal performance. This is because neither the nanostructure 11N nor the porous layer 11P is formed on the aluminum substrate 10t, so that sufficient bonding strength between the aluminum substrate 10t and the epoxy resin 20t cannot be obtained.

  As described above, as is clear from the results of the physical property evaluation of the composite molded body 1 (samples # 1 to # 3) shown in FIG. 6, the composite molding of the present invention prepared according to the manufacturing method described in FIG. In the body 1 (sample # 1), the nanostructure 11N formed on the metal member 10 allows the resin member 20 to enter the gaps between the raised portions 101, thereby obtaining excellent shear strength and sealing performance. it can. Further, in the composite molded body 1 (sample # 1) of the present invention, excellent tensile strength is obtained by the resin member 20 entering each pore 102 by the porous layer 11P formed on the metal member 10. be able to. As a result, according to the method of manufacturing the composite molded body 1 of the present invention shown in FIG. 2, the bonding strength between the resin member 20 and the metal member 10 can be increased by adding a simple configuration (liquid 40). .

  Furthermore, according to the manufacturing method of the composite molded body 1 of the present invention, it is not necessary to repeatedly irradiate the pulse laser PL in order to obtain a sufficient bonding strength in the composite molded body 1, thereby shortening the time required for processing. Can do. Moreover, according to the manufacturing method of the composite molded body 1 of the present invention, it is possible to manufacture the composite molded body 1 having high bonding strength without using a short pulse laser or the like that is expensive to introduce and maintain equipment. it can.

  Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the above-described embodiment. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Further, the technology described in this specification or the drawings achieves a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

1: Composite molding 2: Air nozzle 3: Load part 4: O-ring 10: Metal member 10t: Aluminum substrate 11: First surface 11A: Roughening range 11N: Nanostructure 11P: Porous layer 12: Second surface 20: Resin member 20t: Epoxy resin 21: Air outlet 30: Cover glass 40: Liquid 101: Raised portion 102: Pore 103: Metal splash

Claims (1)

A method for producing a composite molded body of a resin and a metal member,
Stretching a liquid on the surface on which the resin is disposed among the metal members and irradiating a pulse laser through the liquid;
Bonding the resin to the surface;
A processing method comprising:

Images