Conjugate and method for producing conjugate

Abstract

The present invention provides a joint body with high joint strength and a manufacturing method thereof. The joint body 10 of the present invention comprises: a first component 30 having a first joint surface 32 provided with an anchoring portion 34; and a second component 20 having a second joint surface 22, wherein the joint body 10 is obtained by joining the second joint surface 22 with the first joint surface 32, wherein the anchoring portion 34 comprises a plurality of protrusions 35, the plurality of protrusions 35 protrude from the first joint surface 32 and are arranged side by side along a first direction X, the plurality of protrusions 35 have bottom cut portions 35c on both sides in a direction perpendicular to the first direction X, i.e., in a second direction Y, and the cross-sectional shape along the first direction X including the top 35d presents the following shape, i.e., the closer to the first joint surface 32, the wider in the first direction X, so that the length along the first direction X is the longest on the first joint surface 32 side.

Description

Technical Field

[0001] The present invention relates to a joined body and a method for producing the joined body. Background Art

[0002] In a joined body obtained by joining members formed of the same or different materials, an anchor portion having a concavo-convex shape may be formed on the surface of one of the members in order to improve the joining strength.

[0003] For example, Patent Document 1 below proposes a method of attaching metal powder to a joining surface of one component and then subjecting the surface to which the metal powder is attached to laser cladding to thereby bond substantially spherical metal powder to the joining surface to form an anchor portion.

[0004] In order to form an anchor portion on the joint surface and obtain a high anchor effect, it is very important that the anchor portion (metal powder) attached to the joint surface maintains a shape that easily exhibits an anchor effect and increases the bonding strength of the anchor portion to the joint surface.

[0005] However, in the method of Patent Document 1, when the bonding strength of the anchoring portion to the joint surface is to be increased, the metal powder melts and deforms into a shape that is not easy to exert the anchoring effect. In addition, when the shape that is easy to exert the anchoring effect is to be maintained, the metal powder is not easy to melt, and the bonding strength of the anchoring portion to the joint surface is reduced.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2016-130003 Summary of the invention

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to form an anchor portion having a shape that easily exhibits an anchor effect and having a high bonding strength to a bonding surface, thereby improving the bonding strength of a bonded body.

[0010] According to this embodiment, the following solutions [1] to

[12] are provided.

[0011] [1] A joint body comprising: a first component having a first joint surface provided with an anchoring portion, and a second component having a second joint surface, the joint body being obtained by joining the second joint surface to the first joint surface, the joint body being characterized in that the anchoring portion has a plurality of protrusions, the plurality of protrusions protruding from the first joint surface and arranged side by side along a first direction, the plurality of protrusions having bottom cut portions on both sides of a second direction perpendicular to the first direction, and the cross-sectional shape along the first direction including the top is such that the closer to the first joint surface, the wider in the first direction, so that the length along the first direction is longest on the first joint surface side.

[0012] [2] According to the joint body described in the above [1], it is characterized in that the multiple protrusions include: a convex portion, which protrudes from the first joint surface and extends along the first direction; and an expansion portion, which is arranged on the upper part of the convex portion and extends further in the second direction than the convex portion.

[0013] [3] The joint body according to the above [2], characterized in that at least a portion of the plurality of protrusions have the convex strips adjacent to each other in the first direction connected to each other.

[0014] [4] A joint body according to any one of [1] to [3] above, characterized in that a cross section of the plurality of protrusions along the first direction including the top has a shape such that the length in the first direction becomes longer as the protrusions are closer to the first joining surface from the top.

[0015] [5] The joint body according to any one of [1] to [4] above, wherein the second member has a groove extending along the first direction on the second joint surface, and the plurality of protrusions are fitted into the groove.

[0016] [6] The bonded body according to [5] above, characterized in that the bonded body comprises: a third member filled in the groove.

[0017] [7] The joined body according to any one of [1] to [4] above, wherein the hardness of the first member is higher than the hardness of the second member.

[0018] [8] The bonded body according to any one of [1] to [7] above, wherein a metal oxide is provided on the surface of the anchor portion.

[0019] [9] A method for manufacturing a joint body, wherein the joint body is obtained by joining a second joint surface of a second component to a first joint surface of a first component provided with an anchoring portion, wherein the method for manufacturing a joint body is characterized in that it includes the following steps: an anchoring forming step, in which an anchoring portion protruding from the first joint surface and having a plurality of protrusions is formed; and a joining step, in which, after the anchoring forming step, pressure is applied to the second component while the second component is in contact with the plurality of protrusions, so that the plurality of protrusions enter the second component, thereby bringing the first joint surface into contact with the second joint surface, wherein in the anchoring forming step, a pulsed laser is irradiated on the first joint surface while scanning in a first direction, thereby arranging a plurality of protrusions side by side along the first direction, wherein the plurality of protrusions have bottom cut portions on both sides in a direction perpendicular to the first direction, i.e., in a second direction, and wherein the cross-sectional shape along the first direction including the top is such that the closer to the first joint surface, the wider the cross-sectional shape in the first direction is, so that the length along the first direction is the longest on the first joint surface side.

[0020]

[10] The method for manufacturing a joined body according to the above [9], wherein the joining step includes a softening step of softening the second joining surface side of the second member.

[0021]

[11] The method for manufacturing a joint body according to the above-mentioned [9] is characterized in that it comprises a groove forming step, in which a groove extending along the first direction is formed on the second joint surface, and in the joining step, the plurality of protrusions are embedded in the groove.

[0022]

[12] The method for manufacturing a joined body according to the above-mentioned

[11] is characterized in that the groove forming step includes a step of filling the groove with a third component, and the joining step includes a softening step of softening the third component.

[0023] Effects of the Invention

[0024] In the present invention, an anchor portion having a shape that easily exhibits an anchor effect and having a high bonding strength with respect to a bonding surface can be formed, thereby obtaining a bonded body having a high bonding strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a cross-sectional view showing a schematic structure of a bonded body according to the first embodiment of the present invention.

[0026] Figure 2 It means composition Figure 1 A plan view showing a schematic structure of a first joining surface of a first component of a joined body.

[0027] Figure 3 yes Figure 2A-A cross-section diagram.

[0028] Figure 4 yes Figure 2 B-B cross-section diagram.

[0029] Figure 5 It is a diagram showing a softening step in the method for producing a bonded body according to the first embodiment of the present invention.

[0030] Figure 6 It is a diagram showing a pressurizing step in the method for producing a bonded body according to the first embodiment of the present invention.

[0031] Figure 7 It is a diagram showing a softening step in the method for producing a bonded body according to the second embodiment of the present invention.

[0032] Figure 8 It is a diagram showing a pressurizing step in the method for producing a bonded body according to the second embodiment of the present invention.

[0033] Fig. 9 This is a SEM photograph of the metal joint surface of the metal parts in the example of the present invention.

[0034] Fig.10 This is a SEM photograph of a cross section of a metal member in an example of the present invention cut along a first direction.

[0035] Fig.11 This is a SEM photograph of a cross section of the metal member in the example of the present invention cut along the second direction. DETAILED DESCRIPTION

[0036] (First Embodiment)

[0037] Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. It should be noted that in the drawings, the size of components and the like may be exaggerated for the purpose of explanation.

[0038] (1) Joint 10

[0039] First, the bonded body 10 of this embodiment will be described. Figure 1 As shown, the joint body 10 includes: a first component (hereinafter sometimes referred to as a "metal component") 30 including a metal and a second component (hereinafter sometimes referred to as a "synthetic resin component") 20 including a thermoplastic resin. The surface of the metal component 30 has a first joint surface (hereinafter sometimes referred to as a "metal joint surface") 32 having an anchor portion 34 formed thereon. The surface of the synthetic resin component 20 has a second joint surface (hereinafter sometimes referred to as a "resin joint surface") 22. The joint body 10 is obtained by joining the resin joint surface 22 to the metal joint surface 32 to integrate the metal component 30 and the synthetic resin component 20.

[0040] (2) Synthetic resin component 20

[0041] The synthetic resin component 20 is a component obtained by molding a thermoplastic resin into a predetermined shape such as a block, a plate or a line. In addition, the synthetic resin component 20 may be a coating of a thermoplastic resin or an adhesive layer containing an adhesive made of a thermoplastic resin. Specific examples of the thermoplastic resin constituting the synthetic resin component 20 include polypropylene resin (PP resin), polyacetal resin (POM resin), polyphenylene sulfide resin (PPS resin), polyetheretherketone resin (PEEK), acrylonitrile / butadiene / styrene resin (ABS resin), polyethylene resin (PE resin), polybutylene terephthalate resin (PBT resin), polyamide resin (PA resin) such as nylon 66 (PA66), epoxy resin, liquid crystal polymer (LCP resin), modified polyphenylene ether resin (modified PPE), reactive soft polypropylene resin (metallocene reactive TPO resin), perfluoroalkoxy fluorine resin (PFA), ethylene tetrafluoroethylene copolymer (ETFE), etc. In addition, the synthetic resin component 20 can be a carbon fiber reinforced thermoplastic resin (CFRTP) obtained by mixing carbon fibers in the thermoplastic resin as described above, or a material obtained by mixing glass fibers, talcum powder and other reinforcing materials, flame retardants, anti-degradation agents, elastomer components, etc. in the thermoplastic resin as described above.

[0042] (3) Metal parts 30

[0043] The metal component 30 is a component formed by molding a metal into a predetermined shape such as a block, plate, or wire. The metal constituting the metal component 30 is not particularly limited, and various metals can be used. For example, as the metal constituting the metal component 30, copper (Cu), iron (Fe), aluminum (Al), titanium (Ti), nickel (Ni), chromium (Cr), etc. can be used. In addition, the metal component 30 can be composed of an alloy containing two or more metals such as a copper alloy, an iron alloy (iron steel), an aluminum alloy, stainless steel, a titanium alloy, a nickel alloy, and a chromium alloy.

[0044] It should be noted that the metal component 30 preferably has a higher hardness than the synthetic resin component 20 at room temperature (25° C.). In addition, when the metal component 30 and the synthetic resin component 20 are joined, the hardness of the metal component 30 is preferably higher than the hardness of the synthetic resin component 20. In addition, when the metal component 30 and the synthetic resin component 20 are joined, the hardness of the metal component 30 is higher than the hardness of the synthetic resin component 20, and after joining, the hardness of the synthetic resin component 20 at room temperature is higher than the hardness of the metal component 30. Here, the hardness at room temperature is the Vickers hardness measured in accordance with JIS Z 2244, and when the metal component 30 and the synthetic resin component 20 are at a high temperature when the metal component 30 and the synthetic resin component 20 are joined, the hardness is the high-temperature Vickers hardness measured in accordance with JIS Z2252.

[0045] The shape of the metal component 30 can be set to a desired shape according to the purpose, etc. The metal component 30 can be formed by any method, such as casting in which molten metal is poured into a mold of a desired shape, cutting by a machine tool, etc., and stamping by a press machine, etc.

[0046] In addition, the metal component 30 may have an oxide film (metal oxide) formed on the metal joint surface 32 or the anchor portion 34 described later. The oxide film may be a natural oxide film naturally formed on the surface of the metal. In addition, the oxide film may be a film formed on the surface of the metal component 30 by surface treatment using an oxidant, electrolytic treatment using anodization, plasma oxidation treatment, heating oxidation treatment in an oxygen-containing gas, or the like.

[0047] As a preferred solution, the oxide film may be a film formed on the surface of the metal component 30 by rapidly heating the surface of the metal component 30 in an atmosphere of an oxygen-containing gas such as air. The temperature rise of the surface of the metal component 30 per minute during rapid heating is preferably above the melting point of the metal constituting the metal component 30. By rapidly heating the surface of the metal component 30 in this way, a dense oxide film can be formed on the surface of the metal component 30. In addition, by rapidly heating the surface of the metal component 30, microcracks are generated on the surface of the oxide film, and the bonding area with the synthetic resin component 20 is increased.

[0048] It should be noted that the surface of the metal component 30 can be quickly heated by various methods such as laser heating, induction heating or resistance heating. However, considering the faster heating rate during heating and the easier temperature control, it is preferred to heat the surface of the metal component 30 by irradiating laser to form an oxide film.

[0049] In addition, the metal joining surface 32 of the metal member 30 is roughened to provide an anchor portion 34 .

[0050] (4) Anchoring portion 34

[0051] like Figure 2-Figure 3 As shown, the anchor portion 34 formed on the metal joint surface 32 includes a plurality of protrusions 35 protruding from the metal joint surface 32. The plurality of protrusions 35 are arranged in parallel along a predetermined direction X (hereinafter, this direction is referred to as a first direction).

[0052] It should be noted that in this embodiment, if Figure 2 As shown in FIG. 1 , five anchoring portions 34 are provided at intervals on the metal joint surface 32 along a direction Y perpendicular to the first direction X (hereinafter referred to as the second direction). However, one anchoring portion 34 may be provided on the metal joint surface 32, or a plurality of anchoring portions 34 may be provided at intervals on the metal joint surface 32 along the second direction X. In addition, when a plurality of anchoring portions 34 are provided on the metal joint surface 32, as shown in FIG. Figure 2 As shown, one anchoring portion 34 may be arranged to be parallel to another anchoring portion 34 , or one anchoring portion 34 may be arranged to be inclined relative to another anchoring portion 34 .

[0053] Each protrusion 35 constituting the anchor portion 34 includes a convex portion 35 a protruding from the first joint surface 32 and a bulged portion 35 b provided on an upper portion of the convex portion 35 a .

[0054] The convex stripe 35a is in the shape of a narrow convex stripe extending in the first direction X. As a preferred solution, the convex stripe 35a can be connected to the convex stripe 35a of the protrusion 35 adjacent to the first direction X. Figure 2 and Figure 3 As shown, all the protrusions 35 constituting the anchoring portion 34 are connected in a row. In addition, it can also be that: a part of the convex portion 35a is not connected to the convex portion 35a of the protrusion 35 adjacent in the first direction X, and the convex portion 35a is disconnected halfway in the first direction X.

[0055] The bulge 35b provided on the upper part of the convex stripe 35a is shaped to expand in both directions of the second direction Y more than the convex stripe 35a. Thus, each protrusion 35 is contracted and thinned along the second direction Y at the convex stripe 35a provided below the bulge 35b, and undercut portions 35c are provided on both sides of the protrusion 35 in the second direction Y. It should be noted that the bulge 35b may be in various shapes such as a substantially sphere, a substantially ellipsoid, or a solid obtained by connecting a plurality of substantially spheres.

[0056] Each protrusion 35 constituting the anchoring portion 34 is configured as follows: Figure 3The shape of the cross section along the first direction X (hereinafter sometimes referred to as the "first direction cross section") including the top 35d of the protrusion 35 shown is as follows, that is, the closer to the metal bonding surface 32, the wider it is in the first direction X, so that the length along the first direction X of the metal bonding surface 32 side (that is, the contact portion in contact with the metal bonding surface 32) is the longest.

[0057] That is, each protrusion 35 constituting the anchor portion 34 is configured such that, when viewed from the first direction X, the root portion (the portion on the metal bonding surface 32 side) becomes narrower and thinner (see Figure 4 ); When viewed from the second direction Y, the root becomes wider in the first direction X (refer to Figure 3 ).

[0058] As an example of various sizes of the plurality of protrusions 35 constituting the anchor portion 34, the length from the metal bonding surface 32 to the top 35d of the protrusion 35 (the protrusion height of the protrusion 35) is 50 μm to 200 μm, the length of the convex stripe 35a in the second direction Y is 10 μm to 100 μm, the length of the expansion portion 35b in the second direction Y is 50 μm to 200 μm, the length of the convex stripe 35a in the first direction X is 50 μm or more, and the interval between adjacent protrusions 35 in the first direction X is 1 μm to 500 μm. It should be noted that the length of the convex stripe 35a in the first direction X may be equal to the length of the anchor portion 34 in the first direction X.

[0059] As a preferred solution, each protrusion 35 constituting the anchoring portion 34 is configured as follows: Figure 3 The length Lx of the contact portion with the metal bonding surface 32 in the first direction cross section shown is Figure 4 In the cross section along the second direction Y (hereinafter sometimes referred to as “second direction cross section”) including the top 35 d shown, the length Ly of the contact portion with the metal bonding surface 32 is long.

[0060] It should be noted that the first direction cross section of each protrusion 35 constituting the anchoring portion 34 may be a shape in which the length in the first direction X gradually becomes longer as it approaches the metal bonding surface 32 from the top 35d, like the protrusion 35-1, or may be a shape in which the protrusion 35-2 has a portion that narrows and tapers in the first direction X and expands in the first direction X so that the metal bonding surface 32 side of the narrowed portion is the longest in the first direction X (see Figure 3 ).

[0061] (5) Method for manufacturing joint body 10

[0062] Next, a method for manufacturing the bonded body 10 will be described.

[0063] First, the synthetic resin component 20 and the metal component 30 formed into a predetermined shape are prepared. Then, an anchor forming step of forming the anchor portion 34 on the metal joining surface 32 of the metal component 30 is performed. Thereafter, a joining step of joining the resin joining surface 22 of the synthetic resin component 20 to the metal joining surface 32 formed with the anchor portion 34 is performed. Thus, a joined body 10 in which the synthetic resin component 20 is joined to the metal joining surface 32 of the metal component 30 is obtained. The anchor forming step and the joining step are described in detail below.

[0064] (5-1) Anchor Formation Process

[0065] In the anchor forming step, it is preferred that the metal joining surface 32 of the metal component 30 to be joined with the synthetic resin component 20 is irradiated with laser light while moving (scanning) a pulsed laser having a coefficient R of 0.1 to 1.0 as shown in the following formula (1) in the first direction X.

[0066] [Mathematical formula 1]

[0067]

[0068] In the formula (1), h represents the frequency of the laser, and k represents the thermal diffusion coefficient (m 2 / sec), t represents the pulse width of the laser (sec), and v represents the scanning speed of the laser scanning (m / sec).

[0069] When the pulsed laser with the coefficient R being greater than or equal to 0.1 and less than or equal to 1.0 is irradiated onto the metal bonding surface 32, protrusions 35 are arranged side by side along the first direction X. The protrusions 35 are configured such that when viewed from the first direction X, the roots become narrower and thinner, and when viewed from the second direction Y, the roots become wider in the first direction X.

[0070] When the anchor portion 34 is formed by laser irradiation in an oxygen-containing gas as described above, a metal oxide is formed on the surface of the anchor portion 34 .

[0071] When a plurality of anchor portions 34 are formed at intervals in the second direction Y, the metal joining surface 32 is irradiated with pulsed laser light while scanning in the first direction X at positions at predetermined intervals along the second direction Y.

[0072] It should be noted that before the metal joining surface 32 of the metal component 30 is irradiated with a pulsed laser to form the anchor portion 34, a pretreatment may be performed, that is, the portion of the metal joining surface 32 where the anchor portion 34 is to be formed is irradiated with laser to remove impurities attached to the metal joining surface 32.

[0073] (5-2) Joining process

[0074] In the joining process, a softening process is performed, that is, the metal component 30 and the synthetic resin component 20 are heated to soften the resin joining surface 22 side of the synthetic resin component 20. Thereafter, a pressurizing process is performed, that is, the synthetic resin component 20 is pressed against the metal component 30 in a state where the resin joining surface 22 is in contact with the plurality of protrusions 35, thereby causing the plurality of protrusions 35 to enter the synthetic resin component 20, and the metal joining surface 32 is brought into contact with the resin joining surface 22 while being pressurized. Thus, a joined body 10 in which the resin joining surface 22 is joined to the metal joining surface 32 is obtained. In this embodiment, the Figure 5 and Figure 6 The bonding apparatus 50 shown performs a softening step and a pressurizing step to manufacture a bonded body 10 .

[0075] The bonding device 50 includes a table 51 on which the metal member 30 is placed, a heating device 52 for induction heating the metal member 30 placed on the table 51 , and a pressing device 53 for bonding the synthetic resin member 20 to the metal member 30 by pressurization.

[0076] The metal member 30 is placed on the table 51 so that the metal joining surface 32 provided with the anchor portion 34 faces the synthetic resin member 20 .

[0077] The heating device 52 includes an induction heating coil connected to a power supply device (not shown). When driving power is input from the power supply device, the induction heating coil generates a magnetic field to induction heat the metal joining surface 32 of the metal component 30 placed on the worktable 51 .

[0078] The pressing device 53 includes a rod 54 formed of an insulator such as ceramic, and a pressurizing unit 55 that moves the rod 54 to press the synthetic resin component 20 against the metal joint surface 32 of the metal component 30. Figure 5 As shown, the rod 54 can be inserted into the hollow portion of the induction heating coil of the heating device 52 and arranged to face the synthetic resin component 20. The pressurizing unit 55 includes a pneumatic cylinder controlled by an electric pneumatic regulator, a spring-type pressurizer, etc., and is preferably capable of controlling the speed at which the synthetic resin component 20 and the rod 54 are moved together and the pressure at which the synthetic resin component 20 is pressed against the metal component 30.

[0079] To manufacture the joined body 10 using the joining apparatus 50 , first, the metal member 30 is placed on the table 51 in a gas atmosphere so that the metal joining surface 32 provided with the anchor portion 34 faces the synthetic resin member 20 to be provided later.

[0080] Next, the synthetic resin member 20 is arranged so that the resin joint surface 22 faces the metal joint surface 32 of the metal member 30 placed on the table 51 with a gap therebetween. The gap between the metal joint surface 32 of the metal member 30 and the resin joint surface 22 of the synthetic resin member 20 is set to, for example, 0.001 mm to 10 mm.

[0081] Next, the heating device 52 is arranged so as to face the metal joining surface 32 of the metal member 30 with the synthetic resin member 20 interposed therebetween. Figure 5 In the illustrated case, the heating device 52 is disposed above the synthetic resin member 20 , and the synthetic resin member 20 is disposed between the heating device 52 and the metal member 30 .

[0082] Next, a softening process is performed in which the resin joint surface 22 of the synthetic resin member 20 is exposed to a gas heated to the first temperature T1.

[0083] Specifically, a driving power supply is supplied to the heating device 52, and a magnetic field is generated by the induction heating coil provided in the heating device 52 to heat the metal joint surface 32 of the metal component 30. At this time, the driving power supplied to the heating device 52 or the position of the induction heating coil provided in the heating device 52 is adjusted so that the metal joint surface 32 of the metal component 30 reaches the first temperature T1.

[0084] As the metal component 30 is heated as described above, the gas between the metal component 30 and the synthetic resin component 20 is heated to the first temperature T1. As a result, the resin joint surface 22 of the synthetic resin component 20, which is opposite to the metal joint surface 32 of the metal component 30, is exposed to the gas heated to the first temperature T1, and the resin joint surface 22 reaches the first temperature T1. Then, the heating device 52 heats the metal joint surface 32 of the metal component 30 for a predetermined time S1 (for example, 1 to 10 seconds) to perform a softening process in which the resin joint surface 22 side of the synthetic resin component 20 is softened, and then the softening process is terminated and the pressurizing process is entered.

[0085] After the softening process is completed, the pressurizing process is continued, so the heating device 52 stops heating the metal component 30 or reduces the heating amount to cool down (cool) until the temperature of the resin joint surface 22, the metal joint surface 32 and the surroundings (the gas between the metal component 30 and the synthetic resin component 20) reaches the second temperature T2. Then, the synthetic resin component 20 and the metal component 30 are joined at the second temperature T2.

[0086] That is, in the pressurizing step, at a temperature (second temperature T2) lower than the first temperature T1, the pressing device 53 moves the synthetic resin component 20 at a predetermined speed V to make it collide with the metal component 30. At this time, the position of the synthetic resin component 20 corresponding to the front end of the rod 54 is pressed against the metal component 30 with a predetermined pressure P. As a result, the plurality of protrusions 35 provided on the metal joint surface 32 enter the resin joint surface 22 side of the synthetic resin component 20, and the resin joint surface 22 contacts the metal joint surface 32 in a pressurized state, thereby obtaining the joint body 10. Then, the second step is terminated.

[0087] Here, the first temperature T1 may be set to a temperature higher than the deflection temperature Tf under load when a load of 1.8 MPa is applied to the thermoplastic resin constituting the synthetic resin member 20. It should be noted that, when the synthetic resin member 20 is formed of a resin in which a reinforcing material such as carbon fiber, glass fiber, or talc is blended with the thermoplastic resin, the deflection temperature Tf under load when a load of 1.8 MPa is applied to the thermoplastic resin constituting the synthetic resin member 20 is the deflection temperature Tf under load when a load of 1.8 MPa is applied to the thermoplastic resin without the reinforcing material.

[0088] The upper limit of the first temperature T1 can be set to a temperature lower than the decomposition temperature of the thermoplastic resin constituting the synthetic resin member 20, that is, a temperature lower than the temperature at which the thermoplastic resin starts to gasify. For example, the upper limit of the first temperature T1 can be set to 1000° C. Preferably, the upper limit of the first temperature T1 can be set to a temperature 20° C. higher than the melting point Tm of the thermoplastic resin constituting the synthetic resin member 20.

[0089] The second temperature T2 may be a temperature lower than the first temperature T1, and is preferably higher than the deflection temperature Tf under load when a load of 1.8 MPa is applied to the thermoplastic resin constituting the synthetic resin member 20. The second temperature T2 is preferably a temperature lower than the melting point Tm of the thermoplastic resin constituting the synthetic resin member 20. The temperature difference between the first temperature T1 and the second temperature T2 is preferably 1°C or higher and 20°C or lower.

[0090] In this specification, the melting point Tm of a thermoplastic resin is a value measured at a temperature increase rate of 10°C per minute using a differential scanning calorimeter in accordance with JIS K7121. Typical melting points of thermoplastic resins include 168°C for polypropylene resin, 265°C for nylon 66, 232-267°C for polybutylene terephthalate resin, and 280°C for polyphenylene sulfide resin.

[0091] The deflection temperature Tf under load of a thermoplastic resin is the deflection temperature under load measured by a method based on JIS K7191 when a load of 1.8 MPa is applied. Typical deflection temperatures Tf under load when a load of 1.8 MPa is applied are 57 to 65°C for polypropylene resin, 66 to 68°C for nylon 66, 58°C for polybutylene terephthalate resin, and 105°C for polyphenylene sulfide resin.

[0092] It should be noted that the softening step is preferably performed in an oxygen-containing gas such as air. That is, the metal bonding surface 32 and the resin bonding surface 22 are preferably heated to the first temperature T1 in an atmosphere of the oxygen-containing gas, and the metal bonding surface 32 and the resin bonding surface 22 are exposed to the oxygen-containing gas heated to the first temperature T1.

[0093] If the softening process is performed in an atmosphere of oxygen-containing gas, the resin bonding surface 22 of the synthetic resin component 20 reacts with oxygen contained in the oxygen-containing gas, thereby generating functional groups on the resin bonding surface 22 of the synthetic resin component 20 that can react with alkaline or amphoteric oxides to form chemical bonds by neutralization.

[0094] Generally, the surface of the metal component 30 is oxidized and covered with an oxide film containing a metal oxide, so the functional group generated on the resin joint surface 22 is bonded to the metal oxide present on the metal joint surface 32 of the metal component 30 through van der Waals force or hydrogen bonding. In addition, the synthetic resin component 20 and the metal component 30 are bonded in a heated and pressurized state, so that the functional group on the resin joint surface 22 and the metal oxide of the metal component 30 undergo a neutralization reaction (dehydration condensation) to form a covalent bond.

[0095] An example of the functional group generated on the resin bonding surface 22 is at least one of a carboxyl group (-COOH), a carbonyl group (-CO-), and a hydroxyl group (-OH) generated by oxidative decomposition of the thermoplastic resin constituting the synthetic resin component 20. When the thermoplastic resin constituting the synthetic resin component 20 is a resin containing a sulfur atom (heteroatom) such as polyphenylene sulfide resin (PPS), the functional group possessed by the resin bonding surface 22 may include, in addition to the carboxyl group, the carbonyl group, and the hydroxyl group, a functional group containing a heteroatom such as a sulfonic group (-SO3H), a sulfonyl group (-SO2-), a sulfanyl group (-SH), and a disulfide group (-SS-).

[0096] As an example of the neutralization reaction occurring by bonding the metal component 30 and the synthetic resin component 20 , when the resin bonding surface 22 has a carboxyl group (R—COOH) as a functional group and the metal component 30 is composed of a divalent metal, a neutralization reaction such as the following formula (2) occurs.

[0097] 2(R-COOH)+MeO=2(R-COO)-Me+H2O↑···(2)

[0098] In addition, in formula (2), R is the main chain of the thermoplastic resin constituting the synthetic resin member 20 , and Me is the metal constituting the metal member 30 .

[0099] In addition, when the softening process is performed in an atmosphere containing oxygen, the second temperature T2 is preferably a temperature at which the functional group of the resin joint surface 22 of the synthetic resin component 20 and the metal oxide formed on the metal joint surface 32 of the metal component 30 can form a covalent bond through a neutralization reaction. In addition, the second temperature T2 is preferably a temperature at which water generated by the neutralization reaction is removed from the reaction system. The second temperature T2 varies depending on the type of functional group and metal oxide, and therefore it is difficult to determine it indiscriminately, but from the perspective of easily removing water generated by the neutralization reaction, it is more preferably 100°C or more.

[0100] In the softening step, the metal component 30 and the synthetic resin component 20 may be heated so that the metal component 30 and the synthetic resin component 20 as a whole reach the first temperature T1, or the resin joint surface 22 may be exposed to the gas heated to the first temperature T1, and the metal component 30 and the synthetic resin component 20 may be heated so that at least the metal joint surface 32 and the resin joint surface 22 reach the first temperature T1. As a result, the resin joint surface 22 side of the synthetic resin component 20 is softened, and the protrusion 35 can easily enter the synthetic resin component 20 in the pressurizing step, and deformation of the synthetic resin component 20 can be suppressed. It is preferable to perform the softening step so that the hardness of the resin joint surface 22 side of the synthetic resin component 20 is lower than the hardness of the metal component 30.

[0101] In addition, in the pressurizing step, the pressure P when the synthetic resin component 20 is pressed against the metal component 30 is preferably a pressure greater than the compressive yield stress of the thermoplastic resin constituting the synthetic resin component 20. The pressure P varies depending on the thermoplastic resin constituting the synthetic resin component 20, and therefore is difficult to determine indiscriminately, but is preferably 10 to 100 MPa.

[0102] In addition, in the present embodiment, the case where the pressing device 53 moves the synthetic resin member 20 toward the metal member 30 is described. However, the metal member 30 may be moved toward the synthetic resin member 20 .

[0103] When the metal member 30 and the synthetic resin member 20 are partially joined as in the present embodiment, the planar shape of the joined portion may be any shape such as a point shape, a line shape, or a plane shape.

[0104] In addition, during the pressurizing process, the synthetic resin component 20 can be pressed against the metal component 30 in a manner that the anchoring portion 34 provided on the metal joining surface 32 is pressurized as a whole, and the synthetic resin component 20 can also be pressed against the metal component 30 locally (in a point-like manner) in a manner that a portion of the anchoring portion 34 is pressurized.

[0105] In addition, in the present embodiment, the temperature of the synthetic resin component 20, the metal component 30, and their surroundings may be maintained at the second temperature T2 while the synthetic resin component 20 is pressed against the metal component 30. Alternatively, the synthetic resin component 20 may be continuously in contact with the metal component 30 in a pressurized state until the temperature of the synthetic resin component 20, the metal component 30, and their surroundings cools to a predetermined temperature or lower. In this case, it is preferred that the synthetic resin component 20 be in contact with the metal component 30 in a pressurized state until the temperature of the synthetic resin component 20, the metal component 30, and their surroundings cools to a glass transition temperature Tg or lower of the thermoplastic resin constituting the synthetic resin component 20.

[0106] In addition, in the present embodiment, as a joining process, a situation is described in which a synthetic resin component 20 pre-molded into a specified shape is heated and crimped to a metal component 30. However, the metal component 30 formed with an anchor portion 34 may be inserted into an injection molding mold, and molten synthetic resin material may be injected toward the metal joining surface 32 in the injection molding mold, thereby joining the synthetic resin component 20 and the metal component 30.

[0107] (6) Effect

[0108] In the joint body 10 of the present embodiment, the undercut portions 35 c are provided on both sides in the second direction Y of the plurality of protrusions 35 constituting the anchor portion 34 , so that the joint strength between the synthetic resin member 20 and the metal member 30 can be improved.

[0109] In addition, the shape of the first-direction cross section of the plurality of protrusions 35 is such that the closer to the metal joint surface 32, the wider in the first direction X, so that the length along the first direction X is longest on the metal joint surface 32 side. Therefore, while maintaining a shape that easily exhibits an anchoring effect, the bonding strength of the plurality of protrusions 35 with respect to the metal joint surface 32 is improved, or the protrusions 35 themselves are not easily damaged during or after bonding with the synthetic resin component 20, and as a result, the bonding strength of the bonded body 10 can be improved.

[0110] Furthermore, since the plurality of protrusions 35 constituting the anchor portion 34 are arranged side by side along the first direction X, the plurality of protrusions 35 can be provided at appropriate intervals on the metal joint surface 32 , and the joint strength of the joint body 10 can be improved.

[0111] In the present embodiment, when the convex line portions 35 a of the protrusions 35 adjacent to each other in the first direction X are connected, the bonding strength of the protrusions 35 to the metal bonding surface 32 can be further improved.

[0112] In this embodiment, when the first direction cross section of the protrusion 35 is shaped such that the length in the first direction X gradually increases as it approaches the metal joining surface 32 from the top 35 d like the protrusion 35 , the joining strength of the protrusion 35 to the metal joining surface 32 can be further improved.

[0113] In this embodiment, when the hardness of the metal component 30 is higher than that of the synthetic resin component 20, the plurality of protrusions 35 provided on the metal component 30 can easily enter the synthetic resin component 20, and the plurality of protrusions 35 are not easily damaged, thereby obtaining a higher anchoring effect.

[0114] In this embodiment, when a metal oxide is formed on the surface of the anchoring portion 34, the functional group of the resin bonding surface 22 of the synthetic resin component 20 and the metal oxide of the anchoring portion 34 are bonded by dipole interaction. In addition, the functional group of the resin bonding surface 22 and the metal oxide form a covalent bond through a neutralization reaction (dehydration condensation). Therefore, the bonding strength of the bonded body 10 can be improved.

[0115] (Second Embodiment)

[0116] Next, refer to Figure 7 and Figure 8 , a second embodiment of the present invention will be described. It should be noted that the same reference numerals are given to components having the same configuration as those of the first embodiment, and description of the configuration will be omitted.

[0117] In this embodiment, a groove 23 extending along the first direction X is formed on the resin bonding surface 22. The groove 23 is provided at a position corresponding to the plurality of protrusions 35 constituting the anchoring portion 34 provided on the metal component 30. In the bonding process, the plurality of protrusions 35 provided on the metal bonding surface 32 are embedded in the groove 23, and the bonded body 100 is obtained.

[0118] It should be noted that it is preferable to perform a filling process of filling the groove 23 provided in the resin joint surface 22 with a third member (hereinafter sometimes referred to as a "filling member") 24. As a material constituting the filling member 24, any material can be used, but it is preferable to use a material whose hardness is lower than that of the metal member 30 when the metal member 30 and the synthetic resin member 20 are joined, and it is more preferable to use a material that is cured by heating after the metal member 30 and the synthetic resin member 20 are joined. As the filling member 24, it is preferable to use a thermosetting resin such as an epoxy resin or a phenolic resin.

[0119] In the joint body 100 of the second embodiment, a softening step is performed, that is, the filling member 24 is softened by heating the metal member 30 and the filling member 24. Then, a pressurizing step is performed, that is, the synthetic resin member 20 is pressed against the metal member 30 in a state where the filling member 24 is in contact with the plurality of protrusions 35, thereby causing the plurality of protrusions 35 to enter the filling member 24, and the metal joint surface 32 is brought into contact with the resin joint surface 22 while being pressed. Thus, the joint body 100 in which the resin joint surface 22 is joined to the metal joint surface 32 is obtained.

[0120] In this embodiment, the plurality of protrusions 35 provided on the metal joining surface 32 are fitted into the grooves 23 provided on the resin joining surface 22 , and therefore, the protrusions 35 can easily enter the synthetic resin member 20 , and the joining process can be easily performed.

[0121] Furthermore, when the groove 23 provided in the resin bonding surface 22 is filled with the filling member 24 , the plurality of protrusions 35 are unlikely to fall out of the groove 23 , and the bonding strength of the bonded structure 100 can be improved.

[0122] (Change Example)

[0123] The present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are proposed as examples and are not intended to limit the scope of the invention. New embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made within the scope of the main purpose of the invention.

[0124] For example, in the first and second embodiments described above, the case where the metal component 30 formed with the anchor portion 34 and the synthetic resin component 20 including a thermoplastic resin are joined is described, but the present invention can also be applied to the case where metal components including metals are joined to each other and the case where resin components including resins are joined to each other.

[0125] In addition, in the above-mentioned first embodiment and second embodiment, when manufacturing the joint body 10, a softening process is performed by heating to soften the resin bonding surface 22 side of the synthetic resin component 20. However, in addition to heating, the softening process can also be performed by humidification or other methods, or the softening process can be performed by humidification or other methods instead of heating.

[0126] (Example)

[0127] Hereinafter, examples of the present invention and comparative examples 1 and 2 will be described. It should be noted that the present invention is not limited to the examples.

[0128] In the present embodiment and comparative examples 1 and 2, the laser is irradiated to the metal joint surface of the metal component while scanning in the second direction Y at intervals of 0.5 mm in the first direction X, thereby forming an anchor portion in the entire portion of the metal joint surface that contacts the resin joint surface. Then, the synthetic resin component is joined to the metal joint surface formed with the anchor portion. The conditions for irradiating the metal joint surface with the laser in the embodiment and comparative examples 1 and 2 are shown in Table 1 below.

[0129] The details of the metal parts and synthetic resin parts used in Example and Comparative Examples 1 and 2, the dimensions of the metal parts, the dimensions of the synthetic resin parts, and the joining area (overlapping area) between the synthetic resin parts and the metal parts are as follows.

[0130] Metal parts: SUS304 heated to a temperature of 1450°C or higher, the melting point of SUS304, in one second by laser irradiation, and the surface was oxidized and roughened.

[0131] Synthetic resin parts: Susteel (registered trademark) SGX120

[0132] ·Metal component size: 18mm×45mm×1.6mm

[0133] ·Synthetic resin part size: 10mm×40mm×3.0mm

[0134] ·Joint area between metal parts and synthetic resin parts: 10mm×5mm

[0135] The evaluation method is as follows.

[0136] (a) SEM observation of the anchoring part

[0137] Regarding the metal components of Example and Comparative Examples 1 and 2 in which the anchor portions were formed on the metal joint surfaces, SEM observation of the anchor portions was performed in a state where the synthetic resin components were not joined. Figures 9 to 11 A top view and a cross-sectional view showing a metal component of an embodiment, Fig. 9 In FIG. 1 , symbol X represents a first direction, ie, a direction of scanning laser light, and symbol Y represents a second direction.

[0138] like Fig. 9 As shown in FIG. 1 , on the metal joint surface of the metal component of the embodiment, a plurality of protrusions are arranged side by side along the first direction X. The plurality of protrusions arranged on the metal joint surface are as shown in FIG. Fig.10 As shown in FIG. 1 , the first direction cross section of the plurality of protrusions presents a shape in which the length in the first direction X becomes longer as the top of the protrusion approaches the metal bonding surface. Fig.11 As shown, the plurality of protrusions include a convex portion and a bulged portion that expands in both directions of the second direction Y further than the convex portion on the upper portion of the convex portion, and undercut portions are provided on both sides of the protrusion in the second direction Y.

[0139] In addition, the multiple protrusions are configured such that the cross-sectional shape along the first direction including the top is as follows: that is, the closer to the metal bonding surface, the wider it is in the first direction X, so that on the metal bonding surface side, it is the longest in the first direction X, and the length of the contact portion in contact with the metal bonding surface in the first direction cross section is longer than the length of the contact portion in contact with the metal bonding surface 32 in the second direction cross section.

[0140] In the metal joining surface of the metal member of Comparative Example 1, a plurality of convex portions extending in the first direction X are provided at intervals in the second direction Y, but no bulge is formed on the upper portion of the convex portion.

[0141] In the metal joining surface of the metal member of Comparative Example 2, a plurality of grooves extending in the first direction X are provided at intervals in the second direction Y, but no convex line portion or bulged portion is formed.

[0142] (b) Bonding strength

[0143] The dimensions of the metal component, the dimensions of the synthetic resin component, and the bonding area between the synthetic resin component and the metal component in the test method specified in JIS K 6850 were changed as described above, and other conditions were referred to the JIS K 6850 standard, and the measurement was performed using a tensile tester (Autograph AGX-V, Shimadzu Corporation) at a tensile speed of 10 mm / min and a measurement temperature of 25° C. It should be noted that four test pieces were prepared for each of Example and Comparative Examples 1 and 2, and the average of the four measured values ​​was set as the respective bonding strengths.

[0144] Table 1

[0145]

[0146] The results are as follows: Comparative Examples 1 and 2 were 23.7 MPa and 17.7 MPa, while the Example was 29.5 MPa. It was confirmed that the bonding strength was significantly improved in the bonded body of the Example.

[0147] Explanation of symbols

[0148] 10 ...joined body, 20 ...synthetic resin component, 22 ...resin joint surface, 30 ...metal component, 32 ...metal joint surface, 34 ...anchoring portion, 35 ...protrusion, 35a ...convex strip portion, 35b ...expanded portion, 35c ...undercut portion, 35d ...top portion.

Claims

1. A joint body comprising: a first member having a first joint surface provided with an anchor portion, and a second member having a second joint surface, wherein the joint body is obtained by joining the second joint surface to the first joint surface, The conjugate is characterized in that The anchoring portion includes a plurality of protrusions, the plurality of protrusions protrude from the first joint surface and are arranged side by side along a first direction, The plurality of protrusions include: a convex portion protruding from the first joint surface and extending along the first direction; an expansion portion provided on the upper portion of the convex portion and extending further in a direction perpendicular to the first direction, i.e., a second direction, than the convex portion; and an undercut portion provided on both sides of the convex portion in the second direction. The cross-sectional shape along the first direction including the top is in a shape that is wider in the first direction as it is closer to the first joint surface, so that the length along the first direction is longest on the first joint surface side.

2. The joint body according to claim 1, characterized in that: The convex line portions of the plurality of protrusions adjacent to each other in the first direction are connected.

3. The joint body according to claim 1 or 2, characterized in that: The cross section of the plurality of protrusions along the first direction including the top has a shape in which the length in the first direction increases as the protrusions approach the first joint surface from the top.

4. The joint body according to any one of claims 1 to 3, characterized in that: The second member includes a groove extending along the first direction on the second joint surface, and the plurality of protrusions are fitted into the groove.

5. The joint body according to claim 4, characterized in that: The bonded body includes a third member filled in the groove.

6. The joined body according to any one of claims 1 to 5, characterized in that: The first member has a higher hardness than the second member.

7. The joined body according to any one of claims 1 to 6, characterized in that: A metal oxide is provided on the surface of the anchor portion.

8. A method for manufacturing a joint body, the joint body being obtained by joining a second joint surface of a second component to a first joint surface of a first component provided with an anchor portion, The method for manufacturing the joint body is characterized by comprising the following steps: an anchor forming step of forming the anchor portion protruding from the first joint surface and having a plurality of protrusions; and a bonding step of applying pressure to the second member while the second member is in contact with the plurality of protrusions after the anchor forming step so that the plurality of protrusions enter the second member and the first bonding surface is in contact with the second bonding surface, In the anchoring forming process, a pulsed laser is scanned in a first direction while irradiating the first bonding surface, thereby providing a plurality of protrusions side by side along the first direction, wherein the plurality of protrusions have bottom cut portions on both sides in a direction perpendicular to the first direction, i.e., in a second direction, and the cross-sectional shape along the first direction including the top is as follows, i.e., the closer to the first bonding surface, the wider in the first direction, so that on the first bonding surface side, the length along the first direction is the longest.

9. The method for manufacturing a joined body according to claim 8, characterized in that: The joining step includes a softening step of softening the second joining surface side of the second member.

10. The method for manufacturing a joined body according to claim 8, characterized in that: A groove forming step is provided in which a groove extending along the first direction is formed on the second bonding surface; In the joining step, the plurality of protrusions are fitted into the grooves.

11. The method for manufacturing a joined body according to claim 10, characterized in that: The groove forming step includes a step of filling the groove with a third member, and the joining step includes a softening step of softening the third member.

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