JP2018058279A - Production method of resin-metal joined article and resin-metal joined article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain sufficient joining strength without using joining members such as bolts and rivets or adhesives when joining various resins and aluminum materials.SOLUTION: The method of manufacturing a resin-metal joined article 10 according to the present invention is to sequentially carry out a nano spike array fabricating step of fabricating a nano spike array 13 consisting of plural acicular protrusions 13A protruding on the surface of an aluminum material 11, a silane coupling treatment step of carrying out the silane coupling treatment on the surface of the aluminum material 11 where the nano spike array 13 is formed, and a joining step of joining the aluminum material 11 and a resin 21 by solidifying the resin 21 in molten state after entering a gap S formed between the respective protrusions 13A.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for producing a resin-metal bonded body and a resin-metal bonded body, and in particular, bonds a thermoplastic or thermosetting carbon fiber reinforced resin and an aluminum material without using a bonding member such as a bolt or a rivet. The present invention relates to a method for producing a resin-metal bonded body and a resin-metal bonded body.

  Carbon fiber reinforced plastic (CFRP) is known as a composite material of carbon fiber and resin. As CFRP, in addition to thermosetting CFRP using a thermosetting resin as a base material, a thermoplastic material is used as a base material. There is a thermoplastic carbon fiber reinforced plastic (CFRTP) using a resin. Since these CFRPs are lightweight and have high strength, they are widely used as parts for aircrafts and automobiles. In particular, in the automobile field, there is a tendency to adopt multi-materials by adopting various materials at appropriate positions, and CFRTP using a thermoplastic resin as a base material is used from the viewpoint of moldability. The CFRTP is excellent in storage and mass productivity, is easy to post-process and can be recycled, and the manufacturing cost is low.

  When these CFRPs are used as materials for parts such as aircraft and automobiles, it is necessary to join with other parts made of a metal material. For example, in an aircraft, a joining member such as a bolt or a rivet is often used for joining a CFRP part and an aluminum part. However, joining using such a joining member not only increases the weight of the bolt or rivet itself, but hinders the advantages of weight reduction by using CFRP, and the bolt hole tends to be a starting point of damage occurrence. In recent years, there has been a demand for boltless bonding between the resin such as CFRP and the aluminum material.

  By the way, Patent Documents 1 to 3 disclose various methods for joining CFRP and metal without using a joining member such as a bolt or a rivet. That is, Patent Document 1 discloses a method in which fine unevenness of nanometer order is provided on a metal surface, and then the metal surface and CFRP are bonded using an epoxy adhesive. In Patent Document 2, a layer containing a triazine thiol derivative is formed on the metal surface, a thermoplastic resin layer is further provided between the layer and the CFRP, and the thermoplastic resin layer is melted so that the metal and A method for bonding CFRP is disclosed. Furthermore, in Patent Document 3, a thermoplastic resin containing 40 to 80% by weight of carbon fibers made of strip-like fiber bundles containing 1000 to 100,000 single fibers, and a surface roughness of the joining surface of 1 to 100 μm. A method of vibration welding with a metal to be obtained is disclosed.

JP 2010-269534 A International Publication WO2012 / 074083 JP 2016-34734 A

  However, since the method of Patent Document 1 requires an epoxy resin as an adhesive, it takes time to cure the adhesive, and also causes a decrease in adhesive strength due to aging of the adhesive. There exists a problem that recyclability falls by presence of the said adhesive agent. Further, in the method of Patent Document 2, since the lyazine thiol derivative layer and the thermoplastic resin layer are interposed between the metal to be joined and CFRP, the height of the joined body of the metal and CFRP is high. In addition to incurring weight, there is a problem that the recyclability is reduced as in Patent Document 1. Furthermore, in the method of Patent Document 3, usable carbon fiber composite materials are limited, and cannot be applied to a wide variety of CFRP.

  In addition, as a background art of the above-mentioned Patent Document 1, by etching the aluminum alloy, after forming irregularities on the surface of the aluminum alloy, by injecting and injecting the molten thermoplastic resin into the concave portion at a high pressure, A method for joining the thermoplastic resin and the aluminum alloy is disclosed. However, this method is premised on injection molding in order to allow the resin to sufficiently enter the recess from the shape of the recess, and it becomes difficult to join the resin and metal having a complicated shape. In addition, since the concave portion has a gentle valley shape extending to a certain region, the spike effect that the resin engages with the concave portion may be insufficient. Therefore, as proposed in Patent Document 1, sufficient adhesion strength cannot be obtained only by this background art method, and it is necessary to use an adhesive in combination.

  Further, as a background art of Patent Document 2, the CFRTP and the aluminum material are joined to each other by an anchor effect in which the resin enters into the porous body and solidifies by injecting the resin into the aluminum material having a minute porous formed on the surface. A method is disclosed. Even in this method, since injection molding is premised, it is difficult to join a resin having a complicated shape and a metal, and it is difficult for the resin to reach the back of the porous body, and it is difficult to obtain a sufficient anchor effect.

  The present invention has been devised in order to solve such problems, and its purpose is to use a bonding member such as a bolt or a rivet or an adhesive when bonding various resins and aluminum materials. It is providing the manufacturing method of a resin metal joined body and resin metal joined body from which sufficient joint strength is obtained without it.

  In order to achieve the above-mentioned object, the present invention mainly provides a nano-spike array comprising needle-like protrusions protruding on the surface of the aluminum material in a method for producing a resin-metal bonded body obtained by bonding a resin and an aluminum material. The nano spike array manufacturing process to be manufactured and the bonding process of bonding the aluminum material and the resin by sequentially injecting the molten resin into the gap formed between the protrusions and solidifying the resin are sequentially performed. , Is adopted.

  Further, according to the present invention, in the joined body of resin and aluminum material, a large number of cone-shaped projections scattered in a plan view are formed at a joined portion of the aluminum material joined to the resin, and the gaps between the projections are formed. A configuration is adopted in which the resin and the aluminum material are joined in a state of being engaged with each other when the resin enters.

  In the present invention, a nanospike array consisting of many needle-like protrusions protruding on the surface of the aluminum material to be a joint portion with the resin is formed, and the molten resin is intruded into the gaps between the protrusions to solidify. The resin and the aluminum material are joined. At this time, since the tip of the protrusion is sharp, in the bonded state of the resin and the aluminum material, the protrusion can be deeply cut in from the bonded portion side of the resin to the inside, and a high spike effect is achieved. Can be obtained. In addition, since the outer peripheral surface of the protrusion is steep, the resin that has flowed into the outer peripheral surface from the distal end side can easily reach the base side, and the resin can be spread to the back of the gap to obtain a high anchor effect. be able to. Thereby, according to this invention, the joined body of resin and aluminum material joined firmly can be obtained, without using joining members and adhesives, such as a volt | bolt and a rivet. In addition, the manufacturing method according to the present invention does not require injection molding, and can be applied to both thermoplastic resin heat and curable resin, and can bond various resins to an aluminum material. .

(A) It is sectional drawing which represented typically the state of the aluminum material which passed through the anodizing process in the manufacturing method of the resin metal joined body which concerns on this embodiment, (B) is an etching process from the state of (A). It is sectional drawing which represented typically the state of the aluminum material which passed through. (A), (B) is sectional drawing which represented typically the joining process in the manufacturing method of the resin metal joined body which concerns on this embodiment in order.

  Details and examples of the present invention will be described below with appropriate drawings.

  The manufacturing method which concerns on this invention is a manufacturing method of the resin metal joined body characterized by the joining method of resin and an aluminum material. The manufacturing method includes a nanospike array manufacturing step of manufacturing a nanospike array composed of a plurality of needle-like protrusions protruding on the surface of an aluminum material to be a joint portion with the resin, and an aluminum material on which the nanospike array is formed. A silane coupling treatment step for performing a silane coupling treatment on the surface and a joining step for joining the surface of the aluminum material after the silane coupling treatment to the joining portion of the resin are sequentially performed.

  In the present invention, the resin can be applied to a carbon fiber reinforced plastic (CFRP) or the like. As the CFRP, a thermoplastic carbon fiber reinforced plastic (CFRTP) using a thermoplastic resin as a base material, and a base material. Both application with thermosetting CFRP using a thermosetting resin is possible. As CFRTP, in addition to polyamide (PA6, PA66, PA12, etc.) as a base resin, polypropylene, polycarbonate, polyoxymethylene, polyphenylene sulfide, polyphenylene ether, modified polyphenylene ether, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. Various types of materials such as those using phthalate, polyethylene, polystyrene, polymethyl methacrylate, polyether ether ketone, polyether imide, polyamide imide, epoxy, AS resin, ABS resin, and the like can be used.

  In the present invention, as the aluminum material, in addition to pure aluminum, an aluminum alloy containing aluminum as a main component can be applied.

  In the nano spike array manufacturing step, the degreased aluminum material is anodized in an acidic electrolytic solution, so that porous alumina is formed on the surface of the aluminum material 11 as shown in FIG. An anodizing process for forming the layer 12 and an etching process for removing the porous alumina layer 12 having a large number of porous layers formed by the anodizing process are sequentially performed.

  The anodizing treatment employs a known method of forming an oxide film on the surface of the metal by energizing in the electrolytic solution with the metal as the anode. Examples of the electrolytic solution include citric acid, sulfuric acid, oxalic acid, phosphorus Those containing acid, sulfamic acid, boric acid, chromic acid, malonic acid, selenic acid and the like are used.

  In the etching process, the porous alumina layer 12 is removed by immersing a portion of the aluminum material 11 including the porous alumina layer 12 in an acidic processing solution containing at least one of phosphoric acid, chromic acid, oxalic acid, and the like. As shown in FIG. 1B, the nanospike array 13 left on the new surface of the aluminum material 11 thereafter appears. This nano spike array 13 has a shape like a sword mountain for flower arrangement in which many needle-like protrusions 13A protruding on the surface are scattered in a plan view. These protrusions 13A have a conical shape that gradually narrows from the base side toward the distal end side that is substantially dotted. The nano spike array 13 formed here becomes a joining portion 11A of the aluminum material 11 to be joined to the resin.

  In the silane coupling process, a silane coupling agent is applied to the nanospike array 13 in order to firmly bond the aluminum material 11 on which the nanospike array 13 is formed with a resin. As the silane coupling agent used here, one having an isocyanate group is mainly used, but the present invention is not limited to this, and an amino group, mercapto group, thiol group, disulfide group, cyano group, halogen group, sulfone is used. Those having a group can also be used.

  In the joining step, when the resin is thermoplastic CFRTP, as shown in FIG. 2 (A), the joining portion 21A of the resin 21 that has been melted by heating and the joining portion 11A of the aluminum material 11 are combined. The joining portions 11A and 21A are joined to each other by a hot press process of pressing in directions approaching each other. Specifically, in this hot press treatment, the aluminum material 11 having the silane coupling agent applied to the joining portion 11A is heated by being placed on a hot plate H or the like, and the resin 21 is joined to the joining portion 11A. After the portions 21A are overlapped and the resin 21 is melted, the resin 21 is cooled and solidified while the resin 21 is pressurized toward the aluminum material 11, whereby the aluminum material 11 and the resin 21 are joined. The The temperature condition for the hot press treatment varies depending on the type of the base resin, and is set to a temperature equal to or higher than the glass transition temperature and lower than a temperature at which a desired shape can be maintained.

  Further, when the resin 21 is a thermosetting CFRP, when the resin 21 is molded, the bonding portion 11A of the aluminum material 11 is superposed on the bonding portion 21A. For example, the aluminum material 11 is joined to the resin 21 in the process of curing while applying pressure by an autoclave or the like using a semi-cured prepreg sheet.

  In the above joining process, since the joining portion 11A of the aluminum material 11 is the nano spike array 13, the joining portion 11A is firmly joined so as to pierce the resin 21 side, and the spike effect can be enhanced. Further, when the molten resin 12 enters the gap S formed between the projections 13A, the tip side of each projection 13A is substantially point-like, and a wide resin inlet portion between the tips can be secured. At the same time, the separation distance between the adjacent protrusions 13A toward the deep part of the gap S is gradually reduced, so that the resin 21 can be efficiently and sufficiently introduced into the protrusion S, and the anchor effect can be enhanced. .

  As shown in FIG. 2 (B), the resin-metal bonded body 10 obtained by the above manufacturing method has a needle-like protrusion 13A having a sharp point on the bonding portion 11A of the aluminum material 11 scattered in a plan view. The resin 21 enters between the adjacent protrusions 13A, and the aluminum material 11 and the resin 21 are engaged and joined.

  In the present invention, the silane coupling treatment step may be omitted and the nanospike array production step may be followed by the joining step. However, the aluminum material 11 is more easily subjected to the silane coupling treatment step. The bonding strength between the resin 21 and the resin 21 can be increased.

  Next, an example according to the method for manufacturing the resin-metal bonded body 10 will be described.

  As the aluminum material 11, a plate material made of aluminum material of A1050 is used, and as the resin 21, a plate material made of thermoplastic CFRTP in which the base material is combined with carbon fiber as polyamide (PA6) is used. A joined body 10 of the aluminum material 11 and the resin 21 was obtained.

First, the nano spike array 13 is formed on the surface of the aluminum material 11 by the nano spike array manufacturing process. That is, here, first, pretreatment such as degreasing is performed on the aluminum alloy. The degreasing here is performed by immersing an aluminum material in acetone and performing ultrasonic cleaning. However, as this pretreatment, a treatment of completely etching the surface oxide film of the aluminum material 11 with an inorganic material can be performed. Thus, it is considered that the nano spike array 13 can be more effectively manufactured by performing the subsequent processing. Then, anodizing treatment of the aluminum material 11 is performed. As the electrolytic solution here, one containing 2 wt% citric acid and 2 wt% ethylene glycol is used. The applied voltage was 400 V, the current density was 1.2 mA / cm ² , the temperature of the cooling water for cooling the electrolyte was 0 ° C., and the energization time was 9 hours. Then, a porous alumina layer 12 schematically shown in FIG. 1A was formed on the surface of the aluminum material 11. Next, an etching process for removing the porous alumina layer 12 is performed. Here, a treatment solution containing 2% by weight phosphoric acid and 1.5% by weight chromic acid is used, and the treatment is performed at a temperature of 63 ° C. for 60 minutes. Then, a large number of nanospike arrays 13 having a large number of needle-like protrusions 13A schematically shown in FIG. 1B are left on the surface of the aluminum material 11, and the nanospike array 13 is bonded to the resin 21. It becomes part 11A.

  Furthermore, a silane coupling process is performed on the portion of the nano spike array 13 on the surface side of the aluminum material 11 by the silane coupling process. Here, first, ultrasonic cleaning is performed while the aluminum material 11 is immersed in acetone. And the silane coupling agent which has 3-isocyanate propyl triethoxysilane as a main component is diluted to 1 weight%, and is stirred for 5 minutes. Further, the surface portion of the aluminum material 11 on which the nanospike array 13 is formed is covered with a paper waste impregnated with a solution obtained by diluting a silane coupling agent at 1% by weight and left for 1 minute. Thereafter, the aluminum material 11 from which the waste has been removed is placed in an oven heated to 100 ° C., and the aluminum material 11 is left until the silane coupling agent attached to the surface of the aluminum material 11 is dried.

  Next, the joining portions 11A and 21A of the aluminum material 11 on which the nano spike array 13 is formed and the resin 21 are joined by a joining process. Here, as shown in FIG. 2 (A), the aluminum material 11 coated with the silane coupling agent is heated to 290 ° C. with the joining portion 11A side where the nanospike array 13 is formed facing upward. After being placed on the plate H and left for 1 minute, the joining portion 21A of the resin 21 is overlaid on the joining portion 11A. Then, a pressure of 125.4 kPa is applied from above in the figure of the resin 21 in which the joining portion 21A side is in a molten state to make it a pressurized state and left as it is for 3 minutes. Thereafter, the hot plate H is turned off while maintaining the pressurized state, and the temperature is lowered to about room temperature by air cooling, so that the resin 21 is solidified and joined to the aluminum material 11, as shown in FIG. Such a resin-metal bonded body 10 was obtained.

  According to the bonding strength experiment (shear test) of the resin / metal bonded body 10 conducted by the present inventors, the bonding strength of the resin / metal bonded body 10 according to this example was 27.8 MPa. On the other hand, for the same aluminum material 11 as in the previous embodiment, a conventional resin-metal bonded body obtained by bonding the same resin 21 as in the embodiment after performing the silane coupling treatment without forming the nano spike array 13. With respect to (Comparative Example 1), when a bonding strength experiment was performed under the same conditions as described above, the bonding strength was 22.6 MPa. Moreover, about the same aluminum material 11 as the said Example, the same resin 21 as the said Example was joined, without forming the nano spike array 13, using the adhesive sheet which consists of an epoxy resin and an acrylic resin. For the conventional resin-metal bonded body (Comparative Example 2), when the bonding strength experiment was performed under the same conditions as described above, the bonding strength was 25.0 MPa.

  According to the above experimental results, it is proved that the resin-metal bonded body 10 according to the present example has higher bonding strength between the aluminum material 11 and the resin 21 than the conventional resin-metal bonded bodies according to the comparative examples. It was done.

  As another example, the resin-metal bonded body 10 schematically shown in FIG. 2B was also obtained by omitting the silane coupling treatment step with respect to the above example.

  The present invention is also applicable to other resins described above.

DESCRIPTION OF SYMBOLS 10 Resin metal joined body 11 Aluminum material 11A Joining part 12 Porous alumina layer 13 Nano spike array 13A Protrusion 21 Resin 21A Joining part H Hot plate S Gap

Claims (5)

In the method for producing a resin-metal bonded body obtained by bonding a resin and an aluminum material,
A nanospike array manufacturing process for manufacturing a nanospike array consisting of a plurality of needle-like protrusions protruding on the surface of the aluminum material, and solidifying after injecting the molten resin into the gap formed between the protrusions Then, the joining process which joins the said aluminum material and the said resin in order is performed, The manufacturing method of the resin metal joined body characterized by the above-mentioned.   In the nano spike array manufacturing step, the aluminum material is anodized to form porous alumina having a porous structure on the surface of the aluminum material, and then the porous alumina is removed by an etching process. The method for producing a resin-metal bonded body according to claim 1, wherein the nanospike array is formed on a new surface. A silane coupling treatment step is performed between the nanospike array manufacturing step and the bonding step to perform a silane coupling treatment on the surface of the aluminum material on which the nanospike array is formed,
The method for producing a resin-metal bonded body according to claim 1 or 2, wherein, in the bonding step, the resin is bonded to the surface of the aluminum material after the silane coupling treatment. The resin is a thermoplastic carbon fiber reinforced resin using a thermoplastic resin as a base material,
In the joining step, each of the above-described resin components is hot-pressed by pressing in a direction in which the joint portion of the resin that has been melted by heating and the joint portion of the aluminum material on which the nanospike array is formed are brought close to each other. The method for producing a resin-metal bonded body according to claim 1, 2 or 3, wherein the bonded portion is bonded. In the joined body of resin and aluminum,
A large number of cone-shaped projections scattered in a plan view are formed in the joining portion of the aluminum material to be joined to the resin, and the resin and the aluminum material are formed by the resin entering between the projections. A resin-metal bonded body characterized by being bonded in a meshed state.

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