JP6510284B2 - Joining dissimilar materials and manufacturing method thereof - Google Patents

Description

  The present invention is a dissimilar material obtained by joining a first joint surface of a first member made of a polymer material, a metal material or an inorganic material, and a second joint surface of a second member made of a thermoplastic resin. The present invention relates to a joined product and a method of manufacturing the same.

  2. Description of the Related Art Conventionally, there is known a technique for bonding a member made of a metal material or an inorganic material and a member made of a thermoplastic resin by heat welding to obtain a so-called dissimilar material bonded product. In this known technique, a thermoplastic resin having a low melting point is melted and attached to a metal material or an inorganic material, and then the two members are joined by cooling and solidification.

  By the way, the wettability of the molten thermoplastic resin to the metal material or the inorganic material is not so large. That is, the thermoplastic resin tends to be easily repelled from the metal material or the inorganic material. Therefore, it is difficult to ensure the adhesion of the thermoplastic resin to the metal or inorganic material. For these reasons, it is recognized that it is difficult to improve the bonding strength of dissimilar material bonded articles.

  However, particularly in the case of a structural material, it is desirable that the joint strength of the dissimilar material joint be high. In Patent Documents 1 and 2, therefore, it is proposed that the bonding surface of the metal material be subjected to chemical etching to form micropores, and the molten thermoplastic resin be made to enter the micropores, and cooling and solidify in this state. It is done. In this case, an attempt is made to express a so-called anchor effect and thereby improve the bonding strength.

JP, 2009-255429, A JP, 2010-64397, A

  The chemical etching process requires a storage tank for storing the etching solution, and equipment including a processing tank for processing the waste liquid after the chemical etching process. That is, the scale of the environment for processing must be increased. In addition, the cost for treating the waste solution is high. Moreover, since the chemical etching process takes a long time, the problem that different-material-bonded products can not be obtained efficiently is manifested. Furthermore, although it is possible to perform batch processing on a large number of small-sized members, in the case of processing a large-sized member, a large-sized treatment tank is required, and a local treatment The cost is high because the treatment is also difficult.

  The present invention has been made to solve the above-mentioned problems, and has excellent bonding strength, and different materials which can be manufactured at low cost with simple equipment available on a process line for continuous production. An object of the present invention is to provide a joined product and a method of manufacturing the same.

In order to achieve the above object, the present invention relates to a first bonding surface of a first member made of either a polymer material, a metal material or an inorganic material, and at least a thermoplastic resin (but the same as the polymer material) (B) bonding different materials joined with the second bonding surface of the second member including
A SiOx glass film having a thickness of 25 nm or more and hydroxyl groups modified at a density of 3 × 10 ⁻¹⁰ mol / cm ² or more per plane area of the first bonding surface is formed on the first bonding surface ,
The SiOx-based glass film, pore size and wherein the amorphous structure der Rukoto containing fine pores of less than 1 nm.

In addition, the present invention includes a first bonding surface of a first member made of any one of a polymer material, a metal material or an inorganic material, and at least a thermoplastic resin (but excluding the same resin as the polymer material). In a method of manufacturing a dissimilar-material-joined product, the method comprising:
Forming a precursor film of a SiOx-based glass film having a thickness of 25 nm or more on the first bonding surface;
Performing an oxidation treatment on the precursor film to obtain a SiOx glass film in which a hydroxyl group is modified at a density of 3 × 10 ⁻¹⁰ mol / cm ² or more per plane area of the first bonding surface ;
I have a,
The SiOx type glass film, pore size and wherein the resulting Rukoto as an amorphous structure containing micropores of less than 1 nm.

  As described above, in the present invention, an SiOx glass film having a large number of hydroxyl groups bonded is obtained, and the second member is bonded onto the SiOx glass film. In this case, the bonding strength is increased, and peeling is less likely to occur at the bonding interface.

  In addition, as a suitable example of a 2nd member, fiber reinforced resin containing a reinforced fiber is mentioned.

  As a suitable method of obtaining a precursor film, film formation by a chemical vapor deposition (CVD) method may be mentioned. In particular, it is preferable to use a plasma apparatus which plasmifies a gas by energy such as discharge, heat, light and the like. That is, a plasma gas is brought into contact with the starting material, and the resulting decomposition product is deposited in the form of a film on the surface of the first member by a chemical reaction. Thereby, a precursor film having a starting material as a source is formed on the first member.

  In addition, oxidation treatment of the precursor film can also be performed by plasma treatment. That is, the plasma gas may be brought into contact with the precursor film. As a result, the methyl groups on the surface of the precursor film are substituted by hydroxyl groups by chemical oxidation, and as a result, the bonding strength to the thermoplastic resin forming the second member becomes strong.

  According to the present invention, the second member containing the thermoplastic resin is bonded onto the SiOx-based glass film to which a large number of hydroxyl groups are bonded. In this case, the bonding strength with respect to the second member is increased, and peeling is less likely to occur at the bonding interface between the first member and the second member. That is, it is possible to obtain a dissimilar-material-bonded product having a large bonding strength.

BRIEF DESCRIPTION OF THE DRAWINGS It is a whole schematic perspective view of the dissimilar-material joined goods which concern on embodiment of this invention. It is a principal part expansion longitudinal cross-sectional view of the joining interface vicinity of the dissimilar-material joined article of FIG. It is a principal part schematic longitudinal cross-sectional view of the plasma generator used in process which obtains the dissimilar-material joined article of FIG. It is the hole diameter distribution curve of Example 1 and Comparative Example 2.

  BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the bonded different material material according to the present invention and the method for manufacturing the same will be described below in detail with reference to the attached drawings.

  FIG. 1 is an overall schematic perspective view of a dissimilar-material-joined product 10 according to the present embodiment. A part of the first member 12 and the second member 14 is overlapped with each other, and the overlapping portion is joined. Hereinafter, the upper end surface of the first member 12 including the bonding portion is referred to as a first bonding surface 16, and the lower end surface of the second member 14 is referred to as a second bonding surface 18.

  The first member 12 is made of a polymer material, a metal material or an inorganic material. Although various thermosetting resins are mentioned as a specific example of a polymeric material, a thermoplastic resin may be sufficient. Further, preferable specific examples of the metal material include aluminum, aluminum alloy, copper, copper alloy, iron alloys such as iron, carbon steel and stainless steel, and preferable specific examples of the inorganic material include carbon material and the like Glass, ceramics etc. are mentioned.

  The second member 14 may be made of a thermoplastic resin such as polyamide resin, polyvinyl chloride resin, polyethylene resin, polypropylene resin, styrene resin, ABS resin, fluorine resin, polycarbonate, acetal resin, etc., or carbon fiber or glass fiber. And fiber reinforced thermoplastic resin (FRTP). However, when the first member 12 is a polymer material made of a thermoplastic resin, the thermoplastic resin of the second member 14 is a thermoplastic resin different from the polymer material.

  As shown in FIG. 2 in which the cross section in the vicinity of the bonding interface is enlarged, a SiOx-based glass film 20 is provided on the first bonding surface 16 of the first member 12. That is, the first member 12 and the second member 14 are joined via the SiOx-based glass film 20.

The SiOx based glass film 20 has an amorphous structure, and the film thickness is 25 nm or more. In addition, many micropores having a pore size of less than 1 nm exist, which results in a large surface area. Furthermore, the surface roughness is greater than 10 nm. Then, the SiOx based glass film 20 is modified with a hydroxyl (-OH) group. The hydroxyl group is present at a density of 3 × 10 ⁻¹⁰ mol / cm ² or more.

  By the presence of the SiOx glass film 20 having such a configuration, excellent bonding strength is exhibited at the bonding portion. Therefore, when each of the first member 12 and the second member 14 of the dissimilar-material-bonded article 10 is pulled in the direction of arrow X and arrow Y in FIG. 1 and broken, breakage occurs in the second member 14 due to cutting. Alternatively, the resin component and the reinforcing fiber derived from the second member 14 (FRTP plate) remain on the fracture surface on the first member 12 side. This means that the peeling does not occur at the bonding interface between the first member 12 and the second member 14, but the internal failure occurs in the second member 14. That is, the tensile shear strength of the joint exceeds the tensile shear strength of the second member 14.

  In addition, since the SiOx glass film 20 is an insulator, the occurrence of electrolytic corrosion can be avoided even when the first member 12 is made of a metal material. For this reason, deterioration of the dissimilar material bonded product 10 due to corrosion or electrolytic corrosion is avoided.

  Such dissimilar material bonded article 10 can be manufactured as follows.

  First, a precursor film to be the SiOx-based glass film 20 is formed on the first bonding surface 16.

  When this film formation is performed by plasma CVD processing, for example, an open air (registered trademark) plasma system manufactured by Plasma Treat Co., Ltd. can be used. FIG. 3 is an example of such a plasma generator.

  The plasma generator 30 has a hollow casing 32 and an electrode 34 housed inside the casing 32. The electrode 34 therein is electrically connected to a power source 36 for conducting electricity. Be done. An annular insulator 38 is provided on the inner wall of the casing 32 so as to surround the electrode 34.

  In the casing 32, the nozzle member 40 is connected to the lower end portion in FIG. 3. In the nozzle member 40, a discharge hole 42 for discharging a plasma gas to the first bonding surface 16 of the first member 12 is formed.

  That is, the gas supply pipe 44 is connected to the upper end portion of the casing 32, and the ignition gas is led out from the gas supply pipe 44 toward the inside of the casing 32. A part of the ignition gas is plasmatized under the action of the electrode 34 and is discharged from the discharge hole 42 as a plasma gas. The plasma gas flows toward the first member 12 positioned and fixed to face the discharge hole 42.

  In the vicinity of the discharge hole 42, a starting material supply pipe 46 connected to a starting material supply source (not shown) is disposed. The position of the starting material supply pipe 46 can be separated or approached to the electrode 34 by interposing a spacer (not shown) between the casing 32 and the nozzle member 40 or removing the spacer. It is variable. That is, by appropriately changing the distance between the electrode 34 and the starting material supply pipe 46, it is possible to adjust the temperature of the plasma and the strength of the oxidizing power when the starting material contacts the plasma gas.

  Further, from the starting material supply pipe 46, a starting material for forming a water repellent film is derived so as to flow in a direction orthogonal to the flow direction of plasma gas. However, the starting material is supplied only at the time of film formation to be described later, and is not supplied at the time of cleaning processing and oxidation processing to be described later.

  In order to carry out the cleaning process with such a plasma generator 30, the electrode 34 is energized from the power supply 36, and an ignition gas (for example, dry air or dry nitrogen) is provided inside the casing 32 through the gas supply pipe 44. Introduce). The energization causes a glow discharge to occur between the electrode 34 and the nozzle member 40. A part of the ignition gas is excited by the glow discharge to be a plasma gas.

  The plasma gas obtained in this manner is discharged from the discharge holes 42 toward the first member 12. Simultaneously with the discharge of the plasma gas from the discharge hole 42, the starting material supply pipe 46 supplies a starting material for forming a precursor film. Furthermore, by scanning the plasma generator 30 along the first member 12, a precursor film of the SiOx-based glass film 20 is formed on the first bonding surface 16.

  In addition, it is more preferable to perform a cleaning process on the first member 12 in advance. This cleaning process may be performed using various organic solvents such as acetone, or may be performed by plasma process.

  The preferred ignition gas for film formation is dry nitrogen. Further, as a starting material, for example, hexamethyldisiloxane which is a silicon alkoxide, tetraethoxysilane, tetramethoxysilane or the like can be used. The structural formula of hexamethyldisiloxane is as follows.

The high energy of the plasma gas causes partial decomposition of the starting material. That is, the decomposition product is obtained. The decomposition product is sprayed to the first bonding surface 16 together with the plasma gas, adheres to the first bonding surface 16, and then polymerizes to polymerize. As a result, a precursor film made of SiOx glass is formed on the first bonding surface 16. At this point, in the precursor film, Si are bonded to each other via O, and a methyl (-CH ₃ ) group is bonded to Si.

  The precursor film is subjected to an oxidation treatment to substitute a methyl group with a hydroxyl group. Also in this case, it is preferable to use the plasma generator 30 shown in FIG. However, the film formation process and the oxidation process may be performed as a flow operation using separate apparatuses.

  That is, for example, dry air or dry nitrogen is supplied as an ignition gas to obtain a plasma gas. The plasma gas is discharged onto the precursor film through the discharge holes 42. As a result, a methyl group is substituted by a hydroxyl group, and a SiOx glass film 20 modified with a hydroxyl group is formed. In this step, it is not necessary to supply the starting material.

  As described above, according to the present embodiment, the cleaning process, the formation of the precursor film, and the oxidation process can be performed using one plasma generator 30. For this reason, the above-described work can be efficiently performed.

  Moreover, in the plasma generator 30, vacuum equipment such as a chamber and an exhaust pump is not necessary. Therefore, the equipment is simplified and the equipment investment is reduced. Of course, a plurality of plasma generators having nozzles optimized for each process may be used in combination.

In addition to the existence of a large number of micropores as described above, the formed SiOx glass film 20 has a relatively large surface roughness. For this reason, the substantial surface area of the SiOx-based glass film 20 is significantly larger than the area (plane area) calculated as a plane. Therefore, it is possible to bond many hydroxyl groups. That is, a hydroxyl group can be made into the density of 3 * 10 < ^-10 > mol / cm < ² > or more.

  Next, the second bonding surface 18 of the second member 14 is superimposed on the first bonding surface 16 on which the SiOx-based glass film 20 is formed. A heat treatment is performed on the overlapping portion formed by this. If necessary, a load may be applied (that is, pressurization may be performed).

  The second member 14 (thermoplastic resin) is melted by heating. Here, many hydroxyl groups are bonded to the SiOx-based glass film 20. For this reason, the affinity to the molten thermoplastic resin is large. That is, the molten thermoplastic resin sufficiently wets the SiOx-based glass film 20. Therefore, the contact area between the molten thermoplastic resin and the SiOx-based glass film 20, and hence the first bonding surface 16 becomes sufficiently large.

  In this state, the first joint surface 16 and the second joint surface 18 are joined (welded) to each other by cooling and solidifying the thermoplastic resin. Thus, the dissimilar material bonded product 10 can be obtained.

  The bonding strength is high in the bonding portion bonded via the SiOx glass film 20. That is, the dissimilar-material-joined product 10 excellent in bonding strength can be obtained.

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

  For example, the SiOx glass film 20 may be formed by a method other than plasma CVD, such as a chemical vapor deposition (CVD) method or a physical vapor deposition (PVD) method without using plasma. Further, the oxidation treatment may be carried out by a chemical process using an oxidizing agent, heating in an oxidizing atmosphere, irradiation with light such as ultraviolet light, ozone treatment, corona discharge, or the like.

  Furthermore, even when plasma CVD is performed, it may be performed by a vacuum process as known in the art. The means for generating plasma also is not particularly limited as long as it is capable of giving an energy to a substance to generate an excited state, such as an electric discharge other than glow discharge or a flame.

Example 1
As the first member 12, a 1.5 mm thick A5052 (JIS) plate made of an Al-Mg alloy was selected. A cleaning process was performed on one end surface (first bonding surface 16) of the first member 12 by discharging plasma gas from the plasma generator 30 shown in FIG. Next, an ignition gas was supplied as dry nitrogen at 1740 liters / hour, and a plasma discharge was performed with a generator setting with a plasma voltage setup value of 95%, a frequency of 21 kHz, and a plasma cycle time of 25%. The starting material supply pipe 46 was set 4.5 mm below the original position (commercially available position), that is, at a position further away from the electrode 34.

  Also, dry nitrogen gas supplied at 120 liters / hour was used as a carrier gas, and hexamethyldisiloxane was discharged from the starting material feed pipe 46 at 40 g / hour via an evaporator kept at 85 ° C. Thus, hexamethyldisiloxane was polymerized on the first bonding surface 16 to form a precursor film of the SiOx glass film. The distance between the discharge hole 42 and the first bonding surface 16 was 10 mm, and the casing 32 was scanned on the first bonding surface 16 at a speed of 40 m / min.

  Next, the precursor film thus obtained was subjected to an oxidation treatment with a plasma gas. At this time, dry discharge was supplied as an ignition gas at 3000 liters / hour, and plasma discharge was performed with a generator setting with a plasma voltage setup value of 95%, a frequency of 21 kHz, and a plasma cycle time of 25%. The separation distance between the discharge hole 42 and the first bonding surface 16 was 10 mm, and the casing 32 was scanned on the precursor film at a speed of 40 m / min. Thus, the SiOx glass film was formed on the silicon wafer. This is referred to as Example 1.

Comparative Example 1
For comparison, one end face of the A5052 plate was only degreased and washed with ethanol. This is taken as Comparative Example 1.

Comparative Example 2
When forming the precursor film, the SiOx system on the A5052 plate according to Example 1 except that the ignition gas is dry air and the starting material supply pipe 46 is in the in-situ position (position at the time of marketing). A glass film was formed. This is taken as Comparative Example 2.

Comparative Example 3
When forming the precursor film, the procedure is the same as in Example 1 except that the starting material supply pipe 46 is set 1.5 mm below the in-situ position (commercially available position), that is, at a position further away from the electrode 34 Then, an SiOx glass film was formed on the A5052 plate. This is taken as Comparative Example 3.

  The structure and film thickness of the SiOx-based glass film were evaluated by FE-SEM in Example 1 and Comparative Examples 2 and 3 described above. The surface roughness was evaluated by AFM, and the pore diameter was evaluated by the positron annihilation lifetime method, and the amount of hydroxyl groups (density) was measured. When measuring the amount of hydroxyl groups, ion chromatography and TOF-SIMS were employed.

  The results are shown together in Table 1. It can be seen from Table 1 that the amount of hydroxyl groups is significantly larger in Example 1 than in Comparative Examples 2 and 3.

  In addition, in TOF-SIMS, only atomic information on an electrode surface of several nm from the outermost surface of the sample can be obtained on the measurement principle. The measurement results of TOF-SIMS and ion chromatograph are compared with each other, and in Example 1, it can be said that hydroxyl groups are abundantly introduced to the deep of the sample surface having many irregularities. On the other hand, in Comparative Example 2 in which the surface structure is uniform and flat, the introduction of hydroxyl group remains in the outermost surface of the sample.

  Furthermore, the pore size distribution was examined for Example 1 and Comparative Example 2. The results are shown in FIG. From FIG. 4, it can be seen that while a broad peak appears in Example 1, a sharp peak appears in Comparative Example 2. This suggests that in Example 1, the skeletal structure is a disordered amorphous, while in Comparative Example 2, the skeletal structure is ordered. From this, it is clear that Example 1 has a softer SiOx skeleton and less obstacles to the progress of the chemical reaction, in other words, the oxidation reaction of the glass proceeds more easily to the inside. is there.

  The joint by resin injection molding was tried to the above Example 1 and comparative examples 1-3. That is, in a state in which the A5052 plates of Example 1 and Comparative Examples 1 to 3 are accommodated in the cavity of the injection molding apparatus, “Toreca short fiber pellet 1001T15” (carbon fiber content ratio is about 15% by weight ratio) , And injected FRTP), the base material of which is nylon-6. By cooling and solidifying this resin, a dissimilar material bonded product was obtained.

  A tab made of Al was bonded to both ends of the dissimilar material joint and a lap shear tensile test was performed. The results are shown together in Table 2.

  From Table 2, it can be seen that in Example 1 where the hydroxyl group density is large, a large breaking strength can be obtained. Moreover, even if the form of destruction is compared, in Example 1, the resin plate portion is completely cut, and peeling at the bonding interface is not recognized. From this, it is clear that the tensile shear strength of the joint was higher than the tensile shear strength of the second member resin.

  Further, in a sample in which a bond was intentionally caused to be broken by applying a large force locally to the bond of Example 1, the fracture surface on the A5052 plate side was observed with an optical microscope. It was confirmed that the resin component and the carbon fiber remained on the fractured surface of the plate. From this also, it can be understood that the internal failure occurs in the FRTP before the joint between the A5052 plate and the FRTP is broken.

  In Comparative Examples 1 and 3, natural peeling occurred at the bonding portion during cooling. Moreover, in Comparative Example 2, it was recognized that the breaking strength was small and peeling at the bonding interface.

DESCRIPTION OF SYMBOLS 10 ... Dissimilar material joining goods 12 ... 1st member 14 ... 2nd member 16 ... 1st joint surface 18 ... 2nd joint surface 20 ... SiOx system glass film 30 ... Plasma generator 32 ... Casing 34 ... Electrode 36 ... Power supply 38 ... Insulator 40 ... nozzle member 42 ... discharge hole 44 ... gas supply pipe 46 ... starting material supply pipe

Claims (4)

A first joint surface of a first member made of any one of a polymer material, a metal material or an inorganic material, and a second member of a second member containing at least a thermoplastic resin (but excluding the same resin as the polymer material) In dissimilar material joint products joined with joint surfaces,
A SiOx glass film having a thickness of 25 nm or more and hydroxyl groups modified at a density of 3 × 10 ⁻¹⁰ mol / cm ² or more per plane area of the first bonding surface is formed on the first bonding surface ,
The SiOx-based glass film, dissimilar material joint products pore size and wherein the amorphous structure der Rukoto containing fine pores of less than 1 nm. A first joint surface of a first member made of any one of a polymer material, a metal material or an inorganic material, and a second member of a second member containing at least a thermoplastic resin (but excluding the same resin as the polymer material) In a method of manufacturing a dissimilar material joint that joins with a joining surface,
Forming a precursor film of a SiOx-based glass film having a thickness of 25 nm or more on the first bonding surface;
Performing an oxidation treatment on the precursor film to obtain a SiOx glass film in which a hydroxyl group is modified at a density of 3 × 10 ⁻¹⁰ mol / cm ² or more per plane area of the first bonding surface ;
I have a,
The SiOx type glass film, method of manufacturing a dissimilar material joint product pore size and wherein the resulting Rukoto as an amorphous structure containing micropores of less than 1 nm.   The method according to claim 2, wherein the precursor film is obtained by bringing a plasma gas into contact with a starting material.   The method according to claim 2 or 3, wherein the oxidation treatment for the precursor film is performed by bringing the precursor film into contact with a plasma gas.

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