JP2012171221A - Bonded structure member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonded structure member including an FRP reinforced member, for exhibiting excellent bonding strength.SOLUTION: The bonded structure member includes the reinforced member in which at least one piece of continuous fiber-reinforced layers is laminated, and a main structural member. The bonded structure member has a surface bonded to the main structural member of the reinforced member, the surface being processed by a strength improving mechanism.

Description

  The present invention relates to an adhesive structure member composed of a reinforcing member and a main structural material, and more particularly to the shape of the FRP (fiber reinforced resin) reinforcing member and the adhesive surface of the main structural material. Specifically, the bonded structural member of the present invention provides a bonded structural member having a high bonding strength because a grooved portion is present on the surface in contact with the adhesive.

  Polymeric composite materials such as CFRP materials are widely used as structural materials for large passenger aircraft, and are expected to be applied in a wider range of fields than ever before. Due to the characteristics of FRP materials including CFRP materials, bonding using adhesives is often used for bonding between members, and strength problems including design and guarantee are one of the major practical issues. It has become one. However, in general, the strength of the adhesive is lower than the interlayer strength of each member to be bonded, and cracks are generated in the adhesive and progress through the adhesive leading to destruction. Often dominates the strength of the entire member.

  FIG. 9 is a cross-sectional view of the prior art in which the reinforcing member 1 and the main structural member 2 are not provided with a grooved portion in the AA ′ cross section of FIG. 1. Since there is no groove processing portion, even when the crack is generated and propagated inside the adhesive, the crack tip hardly reaches the inside of the reinforcing member 1 or the main structural material 2, and the inside of the adhesive or the adhesive and the reinforcing member 1 or The interface between the adhesive and the main structural member 2 is advanced to break the structure, or the breaking strength is lowered.

  Adhesives composed of polymer materials are known to have reduced strength under high-speed loads, and there is an increasing need for increasing adhesive strength, particularly in applications where impact force is applied, such as automobile structural members.

  With respect to this problem, for example, in Patent Document 1, an adhesion site is obtained by providing a notch in a part of the main structure material adjacent to the adhesion portion with respect to the main structure material to which reinforcing members such as ribs and stiffeners are appropriately attached. This is not a technique to increase the strength of the adhesion site itself.

  As a method for increasing the adhesive strength, for example, Patent Document 2 attempts a method for increasing the adhesive strength by adding a material such as a nanocomposite to the adhesive. In this method, the adhesive is further introduced into the main structural material by pressurizing at the time of bonding to obtain a stronger bonding structure. However, this method is not a method that can be generally used for large structures such as requiring a pressurizing device at the time of bonding, and a method that can be applied more generally and at low cost is desired.

  Also, as an attempt to bond different materials, there is a method of forming a laminated plate made of a thermoplastic resin and a thermosetting resin as shown in Patent Document 3. According to this method, there is an effect of inhibiting crack propagation and improving the strength due to the complicated material interface, but this method can only be used when molding a single laminated plate, It cannot be used as a method for producing a structure formed by bonding.

JP 2003-291219 A JP 2010-234524 A JP 2008-230238 A

  An object of the present invention is to provide an adhesive structure member that exhibits an excellent adhesive strength in an adhesive structure member having an FRP reinforcing member in an attempt to improve such problems of the prior art. A molded article using the adhesive structural member is suitably used for a structural material of electricity, electronic equipment, office automation equipment, home appliances, medical equipment, automobile parts, bicycle parts, aircraft parts, building materials, and sports equipment.

  In order to solve the above-described problems, according to the present invention, the main structural material and at least one continuous fiber reinforcing material layer are laminated, and the reinforcing member is bonded to one surface of the main structural material. There is provided an adhesive structure member having a groove processing portion in which a groove is processed on a surface bonded to the main structural material of the reinforcing member.

  Moreover, according to the preferable form of this invention, the said groove processing part is provided in the long side of the adhesion surface along the substantially parallel direction, The adhesion structure member characterized by the above-mentioned is provided.

  Moreover, according to the preferable form of this invention, the said fiber reinforcement material layer contained in the said reinforcement member by which the said groove | channel was processed is comprised from the textile fabric, The adhesive structure member characterized by the above-mentioned is provided.

  Moreover, according to the preferable form of this invention, the said fiber reinforcement material layer is laminated | stacked on the surface side which contact | connects an adhesive material in the laminated structure of the said reinforcement member, The adhesive structure member characterized by the above-mentioned is provided.

  Moreover, according to the preferable form of this invention, the adhesive structure member characterized by being a laminated board containing at least 1 continuous fiber reinforcement layer is provided.

  According to a preferred embodiment of the present invention, there is provided an adhesive structure member characterized by having a groove processing portion in which a groove is processed on a surface in contact with the reinforcing member of the main structural member.

According to a preferred embodiment of the present invention, the adhesive structural member, wherein the thickness T ₁ of the said fiber reinforcement layer is in the range of 0.2~3mm it is provided.

  According to a preferred embodiment of the present invention, the groove depth t of the groove processed portion is in the range of 20% to 60% with respect to the thickness of the fiber reinforcing material layer. A member is provided.

Moreover, according to the preferable form of this invention, angle (theta) ₁ which makes the groove | channel and the adhesion surface of the said groove process part exists in the range of 30 degree | times-150 degree | times, The adhesion structure member characterized by the above-mentioned is provided.

According to a preferred embodiment of the present invention, there is provided an adhesive structure member characterized in that a cross-sectional shape of the groove processed portion is a triangle, and an angle θ ₂ formed by a bottom surface is in a range of 45 degrees to 90 degrees. Is done.

  Moreover, according to the preferable form of this invention, the said continuous fiber reinforcement is a carbon fiber, The adhesion structure member characterized by the above-mentioned is provided.

  According to still another preferred aspect of the present invention, the adhesive is composed of at least one adhesive selected from an epoxy adhesive, a cyanoacrylic adhesive, a vinyl adhesive, and a plastic adhesive. An adhesive structural member is provided.

  Moreover, according to the preferable form of this invention, the adhesion | attachment structure member used for either an electric, an electronic device, an office automation device, a household appliance, a medical device, a motor vehicle part, a bicycle part, an aircraft part, a building material, and a sports goods is provided. Provided.

  The terms are defined below.

  In the present invention, the “main structural material” refers to a base material that is a main component of the entire structure in which a reinforcing material is joined by an adhesive. The bonding surface shape of the main structural material does not need to be a flat surface, and a curved surface may be formed or a minute hole or a through hole may be formed on the surface.

  In the present invention, the “reinforcing member” refers to a structure that is provided with a strength improving mechanism on an adhesive surface and is bonded to the main structural member by an adhesive. Similar to the main structural material, the shape of the adherend does not need to be flat on the bonding surface, and a curved surface may be formed or there may be a minute hole or a through hole on the surface. The reinforcing member is often used for the purpose of improving the rigidity and strength of the main structural material, and is not limited in size, and a plurality of reinforcing members may be joined to one main structural material. From the viewpoint of weight reduction, there may be a monocoque structure that is hollow when joined to the main structural material. Further, the main structural material and the reinforcing member are collectively referred to as an “adhering material”.

  In the present invention, the “bonding portion” refers to a region where both are bonded via an adhesive when the reinforcing member is bonded to the main structural material, and the reinforcing member and the main at the site where the adhesive strength is desired to be improved. At least one grooved portion as described later exists on the bonding surface of the structural material.

  In the present invention, the “grooved portion” refers to a portion where groove processing has been performed on the surface of the adhesion surface of the reinforcing member and the main structural material. After forming the reinforcing member and the main structural material, processing is performed at a place where adhesive strength is required. When the adhesive breaks and the crack propagates, it becomes a transmission path for propagating the crack to the inside of the reinforcing member or the main structural material.

  In the present invention, the “adhesive” is a substance composed of a material different from the adherend that forms the joint together, and unlike rivet joining or welding joining, when joining to the adherend. , A material for bonding adherends together by adhering along the surface of the adherend as an amorphous object having a Young's modulus lower than that of the adherend, and then curing by heating or drying . Typically, it is a liquid or gel-like object before curing. Epoxy adhesives, cyanoacrylic adhesives, vinyl adhesives, plastic adhesives, and the like are widely used, and they may be used in combination.

  From the viewpoint of improving the bonding strength, the adhesive may be pretreated on the adherend or may be composed of a plurality of components. Moreover, not only liquid but solid and powder may be sufficient. Further, the adhesive may be applied to the reinforcing member instead of the main structural material, or may be applied to both.

  In the present invention, “FRP” refers to a composite material composed of fiber reinforced resin reinforced with fibers, and as a fiber material to be used, in addition to carbon fibers, for example, inorganic fibers such as glass fibers, and Kevlar fibers It is also possible to use reinforcing fibers made of organic fibers such as polyethylene fibers, polyamide fibers, boron fibers, and polyparaphenylene benzobisoxazole (PBO) fibers. Carbon fiber is particularly preferable from the viewpoint of easy control of rigidity and strength of the structural member. Examples of the matrix resin of FRP include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, dicyclopentadiene resins, polyurethane resins, and further, polyamide resins, polyolefin resins, Thermoplastic resins such as polypropylene resin can also be used.

  According to the adhesive structure member of the present invention, it is possible to provide an adhesive structure member having higher strength than a joined body in which the main structural member and the reinforcing member are simply bonded.

It is the adhesion schematic diagram of the reinforcement member made from FRP concerning one embodiment of the present invention, and the main structure material. It is the said schematic sectional drawing in the AA 'cross section of the said schematic drawing of FIG. It is a top view in the adhesion surface of FIG. FIG. 3 is a design example of a groove processing portion provided in the reinforcing member 1 in the schematic cross-sectional view of FIG. 2. In the schematic cross-sectional view of FIG. 2, it is an example schematically showing the progress of a crack when the crack progresses along the groove processing portion 4. It is an example of the said schematic sectional drawing in the AA 'cross section of the said schematic drawing of FIG. It is an example of the said schematic sectional drawing in the AA 'cross section of the said schematic drawing of FIG. It is an example of the said schematic sectional drawing in the AA 'cross section of the said schematic drawing of FIG. It is the said schematic of the prior art which does not provide a groove process part in the reinforcement member 1 and the main structural material 2. FIG.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic perspective view of an adhesive structure in the present embodiment. Reference numeral 100 denotes an adhesive portion composed of the reinforcing member 1, the adhesive material 3 and the main structural material 2. The adhesive 3 is applied for the purpose of joining the reinforcing member 1 to the main structural material 2 to form an adhesive part 100.

  FIG. 2 shows an example of a cross-sectional view of the bonding portion 100 in the AA ′ cross section of FIG. A groove processing portion 4 having a square cross section is provided at the bonding portion of the reinforcing member 1. There is no restriction | limiting in particular in the number, shape, length, and arrangement | positioning of the groove process part 4 in an adhesion | attachment part, You may change for every site | part by the adhesive strength and load calculated | required.

  FIG. 3 is a view of the reinforcing member 1 of FIG. 1 as viewed from above. When an external force is applied to the bonding surface, cracks tend to occur in the direction of low rigidity on the bonding surface. For example, in the rectangular bonding portion shown in FIG. 3 (a), cracks occur from the long side to the opposite long side. Easy to progress. Since the groove processing portion is provided for the purpose of inhibiting the propagation of the crack, the shape of the groove processing portion 4 is substantially the same as the ridgeline formed by bonding and a curved surface as shown in FIG. It is desirable to arrange in a perpendicular direction, that is, parallel to the long side of the bonding surface.

  The continuous groove shape of FIG. 3 (a) is desirable because it is the easiest to process, but the staggered arrangement as shown in FIG. 3 (b) and the arcuate shape as shown in FIG. Since the tip stays and it is easy to guide the crack tip to the inside of the adherend, the effect of improving the strength is high, which is more desirable. Further, as shown in FIG. 3 (d), a groove arrangement that is substantially parallel to all the adhesive material end portions is also more desirable because it has a high strength improvement effect so that it can be easily caught even if a crack propagates from any adhesive end portion. In any case, as shown above, the shape of the groove processing portion is provided so as to inhibit the propagation of cracks, and is approximately in the propagation direction of cracks generated by the load assumed on the bonding surface. It suffices if a groove containing a component that forms a right angle is processed.

  The groove processing method generally uses a grinder using an FRP grindstone in order to ensure the groove processing accuracy, but the method is not particularly limited. It is desirable to use a method that does not cause cracks in the layer during grooving.

  Further, depending on the thickness of the adhesive and the progress position of the crack, there may be a case where the groove processing portion 4 does not enter. Therefore, it is more preferable to provide several groove processing portions on the bonding surface instead of one.

  FIG. 4 shows an enlarged view of a portion B in FIG. 2 when a crack is generated at the bonded portion.

  In this example, the reinforcing member 1 is composed of three laminated materials 1a, 1b, and 1c, each using a fiber reinforced material. Since the strength of the adhesive is lower than the strength of the main structural member 2 and the reinforcing member 1, when a load is applied to the structure and the bonded portion breaks, a crack first occurs inside the adhesive, It propagates through the interface between the adhesive and the main structural member 2 or the reinforcing member 1. Since stress is high at the crack tip, the crack further progresses from the crack tip, and the fracture proceeds so as to cut the joint. When a crack propagates through the interface between the adhesive and the main structural member 2 or the reinforcing member 1, if the grooved portion 4 is present in the main structural member or the reinforcing member, the crack enters the grooved portion 4 and stress is generated in the grooved portion. Becomes higher. Since the stress is increased in the vicinity of the crack tip that has entered the groove processing portion 4, the corner of the groove processing portion is broken, and the crack easily propagates inside the reinforcing material. Cracks that have moved away from the adhesive and entered the reinforcing member proceed between the laminated layers in the reinforcing member, which has lower strength than the strength of the fiber material, but the strength between the laminated layers is higher than the strength of the adhesive. The breaking strength of the part is higher than in the case of a conventional structure having a conventional adhesive structure without a grooved part.

  Since the crack is high stress at the crack tip, the crack usually progresses from the crack tip.However, after the crack tip once enters the laminated layer, it branches again from the middle of the crack in the adhesive layer, and the crack is broken in the adhesive layer. It is also possible to proceed. However, even in this case, since extra fracture energy is required for the branching of the crack, it is compared with the case where the crack tip propagates only in the adhesive having a low resistance like the conventional adhesive structure without the grooved portion. And the intensity | strength of an adhesion part becomes high.

  Since it is important that the material used for the reinforcing member and the main structural material incorporate the crack tip into the member after reaching the crack, and at the same time, do not return the crack tip to the adhesive surface again, use at least one fiber reinforcement. It is necessary to be. More preferably, the fiber reinforcing material is laminated on the side in contact with the adhesive surface in order to easily induce cracks propagating through the inside of the adhesive material, that is, in FIG. 4, the laminated material 1a is at least fiber reinforced. A material is desirable.

The thickness T ₁ of the fiber reinforcement used for the reinforcing member and the main structural material is not preferable because the thickness of the fiber reinforcing material needs to maintain the interlayer strength and maintain the structure even when the crack reaches the interlayer and progresses. Moreover, in order to make a crack progress stably between layers, the thing with a thick thickness and a large surface unevenness | corrugation is unpreferable. That is, the thickness T ₁ of the fiber reinforcement is desirably in the range of 0.2 to 3 mm. For the same reason, it is desirable that the fiber reinforcing material is not formed of a mat material but is composed of continuous fibers having higher rigidity, and it is preferable to use a woven fabric from the viewpoint of the productivity of the molded product.

  FIG. 5 is a schematic diagram of the groove processing portion 4 in the cross section of the reinforcing member 1. In this example, the reinforcing member 1 is composed of three laminated materials 1a, 1b, and 1c. Of the three sheets, the laminated material 1a closest to the main structural material 2 and in contact with the adhesive is desirably a fiber reinforcing material because the grooved portion 4 is provided and the cracks need to be transmitted between the layers as described above. Further, if the depth t of the groove of the groove processed portion 4 is too shallow, the strength of the fiber reinforcing material is too high, and even if the crack tip enters the groove processed portion, the fiber reinforcing material cannot be induced to crack, and is too deep. However, since the strength of the reinforcing member itself is significantly reduced, it is necessary to be within a range of 20% to 60% with respect to the thickness Ta of the fiber reinforcing material layer. Further, when a plurality of groove processing portions are provided, the groove depths t need not all be the same, and the depth t may be changed for each groove.

  If the distance d between the grooved portions in the bonded portion is too small, the rigidity of the reinforcing member is excessively lowered, and delamination is likely to occur in the reinforcing member after the crack has propagated into the reinforcing member. It is desirable to be larger than the thickness h.

  FIG. 6 shows another example of the cross-sectional view of the bonding portion in the cross section A-A ′ of FIG. 1. In addition to the grooved portion 4 provided in the bonded portion of the reinforcing member 1, the grooved portion 5 is also provided in the main structural member 2 facing the reinforcing member on the bonded surface. By providing the grooved portions on the bonding surfaces on both sides, the number of grooved portions 4 provided on the reinforcing member 1 can be reduced, the reduction in the member strength of the reinforcing member 1 can be reduced, and the complementation of the crack tip is enhanced. There are advantages.

FIG. 7 shows still another example of the cross-sectional view of the adhesive portion in the cross section AA ′ of FIG. In this example, the angle formed between the grooved portion 6 provided in the bonding portion of the reinforcing member 1 and the bonding surface is not a right angle but an angle θ ₁ .

  In the case of a structure having an adhesion portion as shown in this example, the load direction is often predictable by the structure, and for example, in the adhesion surface shown in FIG. 4, the crack propagates from the right end side to the left end side. An example is shown.

In the structure of FIG. 7, the crack is the same as in FIG. 4, and shows the shape of the grooved portion provided even when the crack occurs on the right end side and is expected to propagate to the left end side. . If the digging angle of the groove processing part is made small along the propagation direction of the crack, the crack tip is easy to enter the groove processing part and the crack tip is difficult to come out of the groove processing part, so the crack tip is reinforced from the groove processing part. It becomes easy to propagate inside the material, and the crack tip can be taken into the reinforcing material more stably. It is desirable that θ ₁ is not less than 30 degrees and not more than 150 degrees for ease of processing.

FIG. 8 shows still another example of the cross-sectional view of the adhesive portion in the cross section AA ′ of FIG. In FIG. 8A, a groove processing portion 7 having a triangular cross section is provided in the bonding portion of the reinforcing member 1 and is processed so that the angle of the bottom of the triangle is θ ₂ . Further, FIG. 8 (b) shows a case bottom angle theta ₂ of the groove processing section 7 of the triangle is especially 90 °.

When the occurrence of cracks and the propagation direction are clear on the bonding surface, the groove processing portion 7 may have a triangular cross-sectional shape. θ ₂ is desirably 45 degrees or more in order to stably induce cracks to the groove processing portion, and is desirably 90 degrees or less in order to easily propagate the crack tip into the reinforcing material.

  The bonded structural member constructed using the present invention is provided with higher strength than the conventional structure. Therefore, the structural member can be widely used in electric, electronic equipment, office automation equipment, home appliances, medical equipment, and the like. In particular, since the impact strength against dynamic load application is high, it is preferably used for automobile parts, bicycle parts, aircraft parts and sports equipment.

  Moreover, as FRP material which comprises the reinforcement member 1, it is desirable to laminate | stack at least 1 piece of CFRP textile material on the side which contact | connects an adhesive material. That is, since the rigidity of the reinforcing member 1 is appropriately reduced by the groove processing, the crack tip that has propagated in the adhesive through the groove processing portion is guided between the layers in the reinforcing member, and the reinforcing member is stably laminated. Easy to propagate between the inner layers.

1 Reinforcing member 1a Fiber reinforcing layer (thickness Ta) constituting reinforcing member 1
1b Fiber reinforced layer constituting the reinforcing member 1 (thickness Tb)
1c Fiber reinforced layer constituting the reinforcing member 1 (thickness Tc)
2 Main structure material 3 Adhesive material 4 Groove processing portion 5 Groove processing portion 6 Groove processing portion 7 Groove processing portion 8 Crack 100 Adhesion portion θ Angle formed by the groove of the _one groove processing portion and the bonding surface θ ₂ Bottom surface of the triangular groove processing portion Angle

Claims (13)

An adhesive structural member comprising a main structural material and a reinforcing member in which at least one continuous fiber reinforcing material layer is laminated and bonded to one surface of the main structural material, An adhesive structure member having a groove processing portion in which a groove is processed on a surface bonded to a main structural material. The bonded structure member according to claim 1, wherein the groove processing portion is provided along a long side of the bonding surface along a substantially parallel direction. The adhesive structure member according to claim 1 or 2, wherein the fiber reinforcing material layer included in the reinforcing member in which the groove is processed is made of a woven fabric. The adhesive structure member according to any one of claims 1 to 3, wherein the fiber reinforcing material layer is laminated on a surface side in contact with the adhesive in the laminated configuration of the reinforcing member. The adhesive structure member according to any one of claims 1 to 4, wherein the main structural member is a laminated plate including at least one continuous fiber reinforcement layer. The adhesive structure member according to any one of claims 1 to 5, further comprising a groove processing portion in which a groove is processed on a surface of the main structural member that contacts the reinforcing member. Wherein the thickness T ₁ of the fiber reinforcement layer is in the range of 0.2 to 3 mm, the adhesion structure according to any of claims 1 to 6. The adhesion according to any one of claims 1 to 7, wherein a depth t of the groove of the groove processed portion is in a range of 20% to 60% with respect to a thickness of the fiber reinforcing material layer. Structural member. 9. The adhesive structure member according to claim 1, wherein an angle θ ₁ formed by a groove and an adhesive surface of the groove processing portion is in a range of 30 degrees to 150 degrees. 10. The adhesive structure member according to claim 1, wherein a cross-sectional shape of the groove processing portion is a triangle, and an angle θ ₂ formed by a bottom surface is in a range of 45 degrees to 90 degrees. The adhesive structure member according to claim 1, wherein the fiber reinforcement is a carbon fiber. The adhesive according to any one of claims 1 to 11, wherein the adhesive is composed of at least one adhesive selected from an epoxy adhesive, a cyanoacrylic adhesive, a vinyl adhesive, and a plastic adhesive. The adhesive structure member as described. The adhesive structure member according to any one of claims 1 to 12, which is used for any of electric, electronic equipment, office automation equipment, home appliances, medical equipment, automobile parts, bicycle parts, aircraft parts, building materials, and sports equipment. .

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