JP2012206503A - Method for producing metal composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a metal composite by which fellow metal materials or a metal material and another structural member are compounded via a resin cured layer and by which processing is easy and obtained metal composite has excellent adhesive strength.SOLUTION: A preform 10 having a sheet-shaped substrate 2 including a specific thermosetting resin and metal materials 1, 3 arranged or laminated so as to come in contact with the sheet-shaped substrate 2 is molded by heating and pressurizing to produce the metal composite 20 having the metal materials 1, 3 and the resin cured layer. The method for producing the metal composite 20 comprises: a first step for arranging the preform 10 in molding metal molds 11, 12 having surface temperature over 180°C and heating the preform 10 till surface temperature of the metal materials 1, 3 exceeds 180°C; a second step for molding the preform 10 heated at the first step to the metal composite 20 by pressurizing; and a third step for cooling the metal composite 20 molded at the second step till the surface temperature of the metal materials 1, 3 becomes 180°C or below under pressurizing.

Description

  The present invention relates to a method for producing a metal composite.

  A metal composite in which a metal material and a fiber reinforced resin material are laminated and bonded has characteristics such as homogeneous strength and elastic modulus, excellent impact resistance, and heat conductivity that the metal has, and excellent properties that the fiber reinforced resin has. Furthermore, it is possible to achieve both the lightness, the specific strength, the specific elastic modulus, and the properties such as the anisotropy of reinforcement depending on the fiber direction. This metal composite is used for various applications such as aircraft members, automobile members, ship members, mechanical mechanism members, golf clubs, notebook computers, video cameras, and other electronic equipment members (see Patent Documents 1 to 5). reference).

  Conventionally, when producing such a metal composite, after forming the metal material into a predetermined shape, the formed metal material and a sheet-like base material containing reinforcing fibers and a thermosetting resin are laminated, It was common to use a method of curing the thermosetting resin in that state. For example, in Patent Document 4, a composite structural material is manufactured by injecting reinforcing fibers and a thermosetting resin into a metal pipe after being molded and curing the same.

  Also, in the case of manufacturing a metal composite material in which two or more metal materials are bonded via a thermosetting resin, after the metal materials are similarly molded into a predetermined shape, It has been common to place a thermosetting resin and bond a metal material by curing the thermosetting resin.

  However, in such a manufacturing method, the metal material forming step and the forming step of another structural member to be combined are essential, and there is a problem that sufficiently high manufacturing efficiency cannot be obtained. In addition, since the thermosetting resin is arranged after the metal material is molded into a complicated shape, it is difficult to guarantee the adhesive strength in the manufacturing process. For example, even part of the thermosetting resin is sufficiently arranged. If not, problems such as peeling of the metal material may occur when the metal composite is used.

JP 2006-297929 A JP 2010-131789 A JP 2005-161852 A JP 2006-123209 A JP 2009-045129 A Japanese Patent Laid-Open No. 3-177418 JP-A-3-296525 JP-A 64-70523

  An object of the present invention is a method for producing a metal composite in which metal materials or a metal material and another structural material are compounded via a resin hardened layer, and the processability and shortness of the metal material into a complex shape are reduced. It is an object of the present invention to provide a production method capable of producing a metal composite that easily achieves composite in time and is excellent in adhesive strength.

  In order to solve the above-described problems, the present invention has the following configuration. That is, a sheet-like base material containing a thermosetting resin that is at least one selected from the group consisting of an epoxy resin, a phenol resin, a benzoxazine resin, and an unsaturated polyester resin, and placed in contact with the sheet-like base material A method for producing a metal composite comprising a metal material and a cured resin layer provided along the metal material by forming a preform comprising the laminated metal material by heating and pressing. The reform is placed in a molding die and heated until the surface temperature of the metal material exceeds 180 ° C, and the preform heated in the first step is semi-cured with the thermosetting resin. The second step of forming the metal composite by pressurization with the pressure P2 and the metal composite formed in the second step under the pressure P3, the surface temperature of the metal material is 180 ° C. or higher. And a third step of cooling to the bottom.

  Conventionally, when the thermosetting resin as described above is cured, in order to avoid runaway due to rapid progress of the curing reaction, the heating temperature is generally set to 180 ° C. or less at the highest. This situation is the same in the production of metal composites. Normally, when a thermosetting resin is cured at a temperature exceeding 180 ° C., the curing reaction rapidly proceeds to inhibit the formation of the metal composite. It is possible to do.

  In addition, high pressure is required for hot working of metal materials, and if it is heated to high temperature with high pressure, the thermosetting resin will flow out of the molding die excessively, hindering the molding of metal composites. It is possible to do.

  However, in the present invention, in the first step, the surface temperature of the metal material in the preform is heated to a temperature exceeding 180 ° C. so that the curing reaction of the thermosetting resin proceeds to some extent. Even if the metal is hot-worked, the thermosetting resin does not flow out of the molding die excessively by the pressure at that time, and a strong adhesive structure between the metal material and the cured resin layer is formed. Can do.

  When performing hot working of metal, the metal material is inferior in moldability at a temperature of 180 ° C. or less and difficult to form into a complicated shape. In the present invention, the metal material is heated to a temperature exceeding 180 ° C. Therefore, the metal material can be sufficiently softened and a complicated shape can be easily formed. Furthermore, since it is not always necessary to expose the thermosetting resin to a temperature exceeding 180 ° C., it is possible to suppress the rapid progress of the curing reaction as in the prior art.

  According to the present invention, a strong adhesion structure is formed between the metal material and the resin cured layer. The reason for this is that the thermosetting resin is along the rough or fine uneven shape of the surface of the metal material. It is considered that the chemical and physical bonding strength with the metal material was enhanced by filling and curing.

  Furthermore, in the third step, the residual stress in the metal composite is effectively relieved by cooling the metal composite under pressure.

  As described above, according to the method of the present invention, it is possible to easily achieve the workability of a metal material into a complex shape and to combine it in a short time, and to manufacture a metal composite having excellent adhesive strength. .

  In the production method of the present invention, it is preferable that the sheet-like substrate is one in which the thermosetting resin contained therein is cured when heated at 130 ° C. for 10 minutes. According to such a manufacturing method, a molding cycle can be shortened.

  In the production method of the present invention, in the first step, it is preferable to heat until the surface temperature of the metal material becomes 200 to 300 ° C., and the molding die for placing the preform is 200 to 300 ° C. Preferably it has a surface temperature. According to such a manufacturing method, the metal material is softened so that it can be more easily formed into a complicated shape, and the preform can be heated by a simple method.

  The first step, the second step, and the third step are preferably performed in the same molding die. Thereby, since shaping | molding of the said preform and hardening of a thermosetting resin are performed by 1 process, a metal composite body can be manufactured with higher productivity and economical efficiency.

  In the second step and / or the third step, the thermosetting resin is preferably in a cured state. According to such a manufacturing method, since the molding of the preform and the curing of the thermosetting resin are performed simultaneously, the metal composite can be manufactured with higher productivity.

  The pressure P3 is preferably equal to or higher than the pressure P2. Thereby, the curvature and distortion by cooling can be suppressed.

  The pressure P2 is preferably 3 to 30 MPa. This makes it easier to form the metal material.

  It is preferable that the time until the surface temperature of the metal material falls from a temperature exceeding 180 ° C. to 180 ° C. or less is within 3 minutes. With such a manufacturing method, the molding cycle can be further shortened.

  In the second step and / or the third step, it is preferable that the edge of the preform is hemmed or pressed. According to such a manufacturing method, the appearance of the end portion of the metal composite is improved, and the bonding between the metal material and the cured resin layer becomes stronger.

  The method according to the present invention preferably further comprises a step of after-curing the metal composite after the third step. According to such a manufacturing method, the restraint time of the molding die can be reduced, and the adhesion between the metal material and the cured resin layer is further improved.

  The sheet-like substrate is preferably a prepreg containing a fiber substrate and the thermosetting resin impregnated in the fiber substrate. Such a sheet-like substrate functions as a fiber-reinforced composite material after molding. Therefore, the metal composite obtained by such a manufacturing method becomes a laminate of a metal material and a fiber-reinforced composite material, and can satisfy excellent lightness and high mechanical properties.

  It is preferable to add a curing accelerator to the thermosetting resin. By such a manufacturing method, the curing reaction of the thermosetting resin can be promoted, and the molding cycle can be further shortened.

  The metal material is preferably a plate-like body having a thickness of 0.1 to 1 mm. Manufacture using such a metal material improves the moldability of the metal material, and makes it easier to form a complex shape.

  The metal material is preferably roughened physically, chemically or electrically on the surface in contact with the sheet-like substrate. According to such a metal material, a metal composite that is further excellent in adhesiveness between the metal material and the cured resin layer is manufactured.

  The metal material preferably has a plurality of 0.01 to 100 μm holes formed on the surface in contact with the sheet-like substrate. According to such a metal material, a metal composite that is further excellent in adhesiveness between the metal material and the cured resin layer is manufactured.

  The metal forming the metal material is preferably at least one selected from the group consisting of an aluminum alloy, a magnesium alloy, and a titanium alloy. Such a metal material can be particularly easily formed into a complicated shape in the manufacturing method.

  It is preferable that the preform has a sandwich structure in which metal materials are laminated on both sides of a sheet-like substrate. According to such a preform, a metal composite having a sandwich structure in which metal materials are laminated on both surfaces of the cured resin layer is manufactured. According to such a manufacturing method, compared to a method in which two metal materials are individually molded and bonded with a thermosetting resin, the dimensional accuracy as a metal composite is excellent, and high productivity and economy are achieved. A metal composite can be manufactured.

  According to the method of the present invention, for example, a metal composite having an adhesive strength between a metal material and a cured resin layer of 10 MPa or more can be produced.

  The present invention also relates to an electronic device casing comprising a metal composite that can be obtained by the above-described method.

  According to the present invention, there is provided a method for producing a metal composite in which metal materials or a metal material and another structural material are compounded via a resin hardened layer. There is provided a production method capable of producing a metal composite that easily achieves composite in time and is excellent in adhesive strength.

It is a schematic cross section explaining one embodiment of a method of manufacturing a metal composite. It is a schematic cross section explaining other embodiment of the method of manufacturing a metal composite. It is a figure which shows an example of the relationship of temperature, time, and pressure in the method of manufacturing a metal composite. It is a model perspective view which shows the sample for the adhesive strength measurement of a metal composite. It is a schematic cross section explaining the manufacturing method of the metal complex which hemmed in Example 11 of this invention.

  A preferred embodiment of the method for producing a molded body according to the present invention will be described below.

  In this embodiment, it arrange | positions or laminates | stacks so that a sheet-like base material containing a thermosetting resin and a sheet-like base material may be contact | adhered by the method provided with the 1st process, 2nd process, and 3rd process which are mentioned later. A preform including the formed metal material is molded by heating and pressurizing to produce a metal composite including the metal material and a cured resin layer provided along the metal material.

(Sheet substrate)
The sheet-like substrate contains a thermosetting resin. The curing reaction of the thermosetting resin is started in the first step described later. A sheet-like base material is shape | molded with a metal material at the 2nd process mentioned later, and forms the resin cured layer in a metal composite.

  The sheet-like substrate is not particularly limited as long as it is a material containing a thermosetting resin and processed for handling in a sheet form. The sheet-like substrate may be, for example, a resin film coated on a release paper or the like, or a prepreg containing a fiber substrate and a thermosetting resin impregnated in the fiber substrate. At this time, in the prepreg, the state of impregnation of the thermosetting resin is not particularly limited, a complete impregnation state without voids, a semi-impregnation state having voids entirely inside the fiber base material, and unevenness in the fiber base material It may be in a partially impregnated state having an impregnated part and an unimpregnated part, or in a state where a thermosetting resin is adhered and fixed to the surface layer part of the substrate.

  As the thermosetting resin, at least one selected from the group consisting of an epoxy resin, a phenol resin, a benzoxazine resin, and an unsaturated polyester resin is used. By using such a thermosetting resin, a metal composite excellent in productivity and economy can be obtained. Among these, an epoxy resin is preferably used because of its high adhesive strength and a high degree of design freedom according to the environment in which the final product is used. As an epoxy resin, the epoxy resin which has 2 or more of epoxy groups in a molecule | numerator is mentioned. The epoxy resin is preferably a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a novolac type epoxy resin, a naphthalene type epoxy resin, an epoxy resin having a fluorene skeleton, a phenol compound and dicyclopentadiene. Polymer-based epoxy resin, diglycidyl resorcinol, glycidyl ether type epoxy resin such as tetrakis (glycidyloxyphenyl) ethane, tris (glycidyloxyphenyl) methane, tetraglycidyldiaminodiphenylmethane, triglycidylaminophenol, triglycidylamino Glycidylamine type epoxy resins such as cresol, tetraglycidylxylenediamine, biphenyl type epoxy resins, isocyanate modified resins Carboxymethyl selected from resins and mixtures thereof. Epoxy resins may be used alone or in combination. In particular, when a composite material having a good balance between heat resistance and mechanical properties is required, a combination of a trifunctional or higher polyfunctional epoxy resin and a bifunctional epoxy resin, for example, a phenol novolac type epoxy that is a polyfunctional epoxy resin. It is preferable to combine the resin with a bisphenol A type epoxy resin or a bisphenol F type epoxy resin which is a bifunctional epoxy resin.

  Usually, a curing agent is added to the thermosetting resin, and thermosetting is imparted to the resin composition.

  The sheet-like substrate is preferably such that when it is heated at 130 ° C. for 10 minutes, the thermosetting resin contained therein is cured. In order to obtain a sheet-like base material having appropriate curing characteristics, a curing agent to be added to the thermosetting resin is selected. The kind of hardening | curing agent can be suitably changed according to the kind of thermosetting resin. For example, when an epoxy resin is used as the thermosetting resin, the curing agent is a curing agent that polymerizes polyaddition type amine compounds, acid anhydrides, phenols, mercaptans, isocyanates, etc., tertiary amines, imidazole, Lewis Examples thereof include a curing agent that functions as an initiator for anionic polymerization or cationic polymerization of acid or the like. In particular, an amine compound is preferable because it has a high degree of design freedom depending on the application.

  The amine curing agent refers to a curing agent having a nitrogen atom in the curing agent molecule. Examples of the curing agent include 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, and diethyltoluenediamine. Aromatic polyamine compounds having active hydrogen, diethylenetriamine, triethylenetetramine, isophoronediamine, bis (aminomethyl) norbornane, bis (4-aminocyclohexyl) methane, aliphatic having active hydrogen such as dimer acid ester of polyethyleneimine Amines, modified amines obtained by reacting these amines with active hydrogen with compounds such as epoxy compounds, acrylonitrile, phenol and formaldehyde, thiourea, dimethylaniline, dimethylbenzylamine Polycarboxylic acid hydrazides, such as 2,4,6-tris (dimethylaminomethyl) phenol and tertiary amines such as monosubstituted imidazoles, dicyandiamide, tetramethylguanidine, adipic acid hydrazide and naphthalenedicarboxylic acid hydrazide And Lewis acid complexes such as boron trifluoride ethylamine complex.

  Of the above, dicyandiamide and aromatic polyamine compounds are preferably used as the amine curing agent. When dicyandiamide or an aromatic polyamine compound is used, a cured product having a high elastic modulus and heat resistance can be obtained from the thermosetting resin. Among them, dicyandiamide, 3,3′-diaminodiphenylsulfone, and 4,4′-diaminodiphenylsulfone can be used to obtain a resin composition having excellent heat resistance, particularly moisture and heat resistance, and when mixed into an epoxy resin into a single solution It is particularly preferable because it has excellent storage stability.

  In addition to the curing agent, an appropriate curing accelerator can be added to the thermosetting resin in order to increase the curing activity. For example, to dicyandiamide, 3-phenyl-1,1-dimethylurea, 3- (3,4-dichlorophenyl) -1,1-dimethylurea (DCMU), 3- (3-chloro-4-methylphenyl) -1 , 1-dimethylurea, urea derivatives such as 2,4-bis (3,3-dimethylureido) toluene and imidazole derivatives can be suitably combined as a curing accelerator. In particular, a combination of dicyandiamide and a compound having two or more urea bonds in one molecule is preferable. Examples of the compound having two or more urea bonds in one molecule include 1,1′-4 (methyl-m-phenylene) bis (3,3-dimethylurea) or 4,4′-methylenebis (phenyldimethylurea). preferable. When these compounds are used, the flame retardancy of a thin plate is greatly improved, and it is particularly preferable when applied to electrical / electronic material applications.

  In addition, there is an example in which an aromatic amine is combined with a boron trifluoride ethylamine complex as a curing accelerator.

  As the curing agent, a latent curing agent activated at 70 to 125 ° C. can also be used. Here, activating at 70-125 degreeC means that reaction start temperature exists in the range of 70-125 degreeC. Such reaction initiation temperature (hereinafter referred to as activation temperature) can be determined by differential scanning calorimetry (hereinafter referred to as DSC). Specifically, for an epoxy resin composition obtained by adding 10 parts by weight of the curing agent to be evaluated to 100 parts by weight of a bisphenol A type epoxy resin having an epoxy equivalent of about 184 to 194, the tangent of the inflection point of the exothermic curve obtained by DSC And the tangent of the baseline. When the activation temperature is less than 70 ° C, the storage stability may not be sufficient, and the curability as expected when the activation temperature exceeds 125 ° C may not be obtained.

  The latent curing agent activated at 70 to 125 ° C. is not particularly limited as long as it has such an activation temperature. For example, an amine adduct type latent curing agent, a microcapsule type latent curing agent, an amine imide, Examples thereof include blocked isocyanates, compounds obtained by reacting an epoxy group with a carbamic acid ester to form an oxazolidinone ring, vinyl ether blocked carboxylic acids, salts of imidazole and carboxylic acid, amine carbamine salts, onium salts, and the like.

  An amine adduct type latent curing agent is a compound having a high molecular weight by reacting an active ingredient such as a compound having a primary, secondary or tertiary amino group or various imidazole compounds with any compound capable of reacting with those compounds. Means that it has become insoluble at storage temperature. As the amine adduct type latent curing agent, “Amicure” (registered trademark) PN-23, MY-24 (above, manufactured by Ajinomoto Fine Techno Co., Ltd.), “Adeka Hardener” (registered trademark) EH-3293S, EH- 3615S, EH-4070S (Asahi Denka Kogyo Co., Ltd.), "Fuji Cure" (registered trademark) FXE1000, FXR-1020 (Fuji Kasei Kogyo Co., Ltd.), etc. can be used. As the latent curing agent, “Novacure” (registered trademark) HX-3721, HX-3722 (manufactured by Asahi Kasei Kogyo Co., Ltd.) and the like can be used. Among these, an amine adduct type latent curing agent such as “Amicure” PN-23 has excellent storage stability at room temperature and remarkable rapid curability, and can be preferably used.

  A microcapsule type latent curing agent is an epoxy resin that is formed by coating a curing agent as a core and polymer material such as epoxy resin, polyurethane resin, polystyrene, polyimide, or cyclodextrin as a shell. And the contact with the curing agent is reduced.

  When a specific curing agent is combined with a latent curing agent which is activated at 70 to 125 ° C., rapid curing can be performed at a low temperature. For example, a curing agent system in which an organic acid dihydrazide such as bazine dihydrazide is combined with a latent curing agent such as “Amicure” PN-23, or a curing agent system in which a curing accelerator such as DCMU is combined with a latent curing agent is 110 It is preferably used because it can be cured at about 10 minutes.

  Curing agent compound obtained by heating reaction of amine compound, epoxy resin and urea described in Patent Document 6, N, N-dialkylaminoalkylamine described in Patent Document 7, cyclic amine having nitrogen atom having active hydrogen and isocyanate Alternatively, a curable compound obtained by heat-reacting with an epoxide, a masterbatch type curing agent having a specific amine compound described in Patent Document 8 as a core and a reaction product of the epoxy resin as a shell are also used. be able to. These may be used alone or in combination.

  Components other than the above-described components may be added to the thermosetting resin. For example, a thermoplastic resin can be blended with a thermosetting resin in order to control viscoelasticity and impart toughness. In order to improve the flame retardancy, a halogen compound, a phosphorus compound, a nitrogen compound, a metal oxide, a metal hydroxide, or the like can be added to the thermosetting resin.

  When the sheet-like substrate is a prepreg, as the fiber substrate, for example, a fiber structure such as long fibers aligned in one direction, a single tow, a woven fabric, a knitted fabric, a non-woven fabric, a mat, and a braid is used. Can do.

  The unidirectional prepreg is preferable because the fiber direction is uniform and the fiber bending is small, so that the strength utilization rate in the fiber direction is high. In addition, it is preferable to use a laminate in which a plurality of unidirectional prepregs are laminated in an appropriate layer configuration as the fiber base material because the elastic modulus and strength in each direction can be freely controlled. A woven prepreg is also preferable because a material having low strength and elastic anisotropy can be obtained. It is also possible to form a fiber substrate using a plurality of types of prepregs, for example, both unidirectional prepregs and woven prepregs.

  The fiber used for the fiber substrate is not particularly limited, but a so-called reinforcing fiber is preferable, and a carbon fiber excellent in specific elastic modulus and specific strength is particularly preferable in an application where there is a high demand for weight reduction and high strength of the material. . In addition to carbon fibers, fibers such as glass fibers, aramid fibers, boron fibers, PBO fibers, high-strength polyethylene fibers, alumina fibers, and silicon carbide fibers can be used as the reinforcing fibers, and two or more of these fibers can be used. You may mix and use.

  The thermosetting resin may be impregnated to the inside of the fiber base material, or may be localized on the surface layer in the case of a sheet-like prepreg.

  The prepreg can be produced by a wet method in which a thermosetting resin is dissolved in a solvent such as methyl ethyl ketone and methanol to lower the viscosity and impregnation, or a hot melt method in which the viscosity is reduced by heating and impregnated.

  The wet method is a method of obtaining a prepreg by immersing a fiber base material in a solution of a thermosetting resin, then pulling it up and evaporating the solvent using an oven or the like.

  The hot melt method is a method in which a fiber base material is directly impregnated with a thermosetting resin whose viscosity has been reduced by heating, or a resin film in which a thermosetting resin is coated on release paper or the like is prepared, and then a fiber is prepared. This is a method of obtaining a prepreg by laminating the resin film from both sides or one side of the substrate and impregnating the resin by heating and pressing. This hot melt method is preferable because substantially no solvent remains in the prepreg.

  When obtaining a prepreg by the hot melt method, the temperature of the thermosetting resin in the step of coating the resin film is preferably 30 to 80 ° C, and more preferably 40 to 70 ° C. If the temperature is less than 30 ° C., the viscosity may increase and the basis weight of the resin film may not be stable. If the temperature exceeds 80 ° C., curing of the resin may progress during coating and the viscosity may increase significantly.

(Metal material)
The metal material is heated to a temperature exceeding 180 ° C. in a first step described later, and is formed in a second step described later to form a metal material in the metal composite.
The metal that forms the metal material is preferably at least one selected from the group consisting of an aluminum alloy, a magnesium alloy, and a titanium alloy. For example, as aluminum alloys, industrial pure aluminum A1050, A1100, A1200, Al-Cu series A2017, A2024, Al-Mn series A3003, A3004, Al-Si series A4032, Al-Mg series A5005, A5052, A5083, Al-Mg-Si-based A6061, A6063, Al-Zn-based A7075, and the like.
Examples of magnesium alloys containing magnesium include Mg-Al-Zn-based AZ31, AZ61, and AZ91. As for pure magnesium, a plate-like one is poorly distributed, and a magnesium alloy is generally used.
Titanium alloys include industrial pure titanium 1-4 TP270H, alloys added with 11-23 palladium, alloys added with cobalt and palladium, 50 (α alloy), 60 (α-β) Alloy), Ti-6Al-4V corresponding to 80 types (β alloy), and the like.

For example, although metals such as copper and stainless steel can be suitably selected, in the manufacturing method according to the present embodiment, it can be easily formed into a complicated shape, and is a material having high specific rigidity. It is preferable for achieving thinness, lightness and high rigidity.
The shape of the metal material is not particularly limited, and may be left unmolded as a molding material, may be molded into a target shape, or may be preliminarily shaped closer to the target shape. From the viewpoint of economy, an unmolded state is preferable. For example, the metal material is preferably a plate-like body having a thickness of 0.1 to 1 mm. The thickness of the metal material is more preferably 0.3 to 0.8 mm. By using such a metal material, forming into a complicated shape can be performed particularly easily.

  The metal material may be surface roughened physically, chemically or electrically. When the metal material is roughened on the surface in contact with the sheet-like base material, a metal composite having particularly excellent adhesion between the metal material and the cured resin layer is produced. Various methods can be employed as the surface roughening method. Examples of physical surface roughening include sand blasting and polishing with sand paper. Examples of the chemical surface roughening method include a method of immersing the above-mentioned surface of the metal material in a polishing liquid capable of eroding the metal material. Examples of the electrical surface roughening method include a method of electrochemically roughening the surface by immersing the surface of the metal material in an electrolytic solution. These surface roughening methods may be used alone or in combination of two or more.

  The metal material preferably has a plurality of 0.01 to 100 μm holes formed on the surface in contact with the sheet-like substrate. More preferably, a plurality of 0.1 to 10 μm holes are formed. According to such a metal material, a metal composite that is further excellent in adhesiveness between the metal material and the cured resin layer is manufactured.

(preform)
The preform includes a sheet-like base material and a metal material arranged or laminated so as to be in contact with the sheet-like base material. The preform is heated in a first step described later, and is pressure-formed in a second step described later to form a metal composite.

  Examples of the preform include a preform having a two-layer structure in which a metal material is laminated on a sheet-like base material, a preform having a sandwich structure in which metal materials are laminated on both sides of the sheet-like base material, and a sheet-like base material. Various forms such as a preform having a structure in which a metal material is abutted on the side surface can be used depending on the target metal composite. Furthermore, by applying them, a preform having a structure in which sheet-like base materials and metal materials are alternately laminated, a preform having a structure in which metal materials are laminated on a laminate of sheet-like base materials, and these structures are used. Examples thereof include a preform having a sandwich structure in which core materials used in the sandwich structure are further laminated. In a preform having these laminated structures, it is preferable to adopt a symmetrical laminated structure from the viewpoint of suppressing warpage and twisting of the resulting metal composite.

  Among the preforms, a preform having a sandwich structure in which metal materials are laminated on both sides of a sheet-like substrate, and a preform having a sandwich structure in which metal materials are laminated on both sides of a laminate of sheet-like substrates, respectively. Is preferred. According to such a preform, a metal composite having a sandwich structure in which metal materials are laminated on both surfaces of the cured resin layer is manufactured. That is, when the manufacturing method according to the present embodiment is performed using such a preform, compared to a method in which two metal materials are individually molded and bonded with a thermosetting resin, a metal composite is obtained. It is excellent in dimensional accuracy, and a metal composite can be easily manufactured in a short process.

  Although the thickness of the preform is not particularly limited, it is preferably 0.5 to 5 mm, more preferably 1 to 3 mm from the viewpoint of forming a complicated shape of the metal composite.

(Metal composite manufacturing method)
Hereinafter, each process of the manufacturing method of the metal complex which concerns on this embodiment is demonstrated in detail.

  In the first step, the metal material in the preform placed in the molding die is heated to a temperature of which the surface temperature exceeds 180 ° C., and the sheet-like substrate is also heated at the same time. Curing is advanced and the thermosetting resin is semi-cured.

  Here, “semi-cured” means a state between an uncured state and a cured state. The semi-cured thermosetting resin has a certain degree of fluidity. For example, when a thermosetting resin is heated and a viscosity curve due to change over time is measured, the difference between the saturated viscosity and the minimum viscosity is displayed as a percentage, and the state is 10 to 90% of the saturated viscosity. It can be said to be semi-cured. The cured state is a state in which the thermosetting resin does not flow or deform due to demolding, and a state having a viscosity exceeding 90% with respect to the saturated viscosity can be referred to as a cured state.

  Moreover, the method of confirming a hardening state from the glass transition temperature (henceforth Tg) of a thermosetting resin can also be illustrated. For example, the Tg when the increase in Tg with progress of the saturation is saturated and the minimum value of Tg (Tg of the uncured thermosetting resin) are measured in advance, and the minimum value of Tg is determined from the saturated Tg. A state in which the difference is displayed as a percentage and the Tg is 10 to 90% with respect to the saturated Tg can be referred to as semi-curing. A state where the Tg is more than 90% with respect to the saturated Tg can be referred to as a cured state. The correlation between the heating temperature and heating time of the thermosetting resin and Tg is measured in advance, and based on this correlation, an approximate Tg can be interpolated from the molding conditions. Tg can be measured by a method using DSC.

  Furthermore, the method of confirming a hardening state from the emitted-heat amount measured by DSC of a thermosetting resin can also be illustrated. For example, the calorific value of the uncured thermosetting resin is measured in advance, and the residual reaction rate can be estimated from the ratio of the calorific value of the thermosetting resin after heating. A state in which the residual reaction rate is 10 to 90% can be referred to as semi-curing. A state of less than 10% can be referred to as a cured state.

  If it can be said that it is a semi-cured state in any of these measurement methods, in the present invention, it can be considered that the thermosetting resin is in a semi-cured state.

  The thermosetting resin that has undergone the first step is in a semi-cured state, and is molded following the metal material in the second step, but does not flow excessively and is cured in a shape according to the metal material. .

  The method for heating the metal material is not particularly limited. For example, a molding die having a surface temperature exceeding 180 ° C, preferably a surface temperature of 200 to 300 ° C, more preferably a surface temperature of 200 to 250 ° C is used as the metal material. The metal material can be heated by a method of contacting with the metal. Here, the surface temperature of the molding die means the temperature of the cavity for molding the metal composite. There is no particular restriction on the method of raising the surface temperature of the molding die. The method of mounting the molding die on a hot press, the method of embedding a heater in the molding die, direct heating from the outside by electromagnetic induction heating, halogen heater, etc. In order to shorten the heating time, it may be preheated with a heater, oven, torch or the like.

  In the first step, the preform is heated so that the surface temperature of the metal material is usually higher than 180 ° C, preferably 200 to 300 ° C, more preferably 200 to 250 ° C. According to such a manufacturing method, it becomes easier to form a complicated shape in the subsequent second step by softening the metal material. Although at least a part of the surface of the metal material may be at the above temperature, it is preferable that the surface temperature of the portion where the metal complex is deformed by pressure molding is the above temperature.

  When the preform is heated in the first step, the sheet-like substrate is also heated together with the metal material. Usually, a temperature difference occurs between the sheet-like base material and the metal material, and in order to raise the temperature of the entire sheet-like base material to the above temperature, a heat amount is required rather than the metal material. Never become. Such a temperature difference can moderately adjust the curing reaction of the thermosetting resin. That is, the thermal conductivity of the sheet-like base material is lower than that of the metal material, the sheet-like base material is heated via the metal material, the distance from the heat source of the sheet-like base material, A large specific heat is considered to be one of the reasons why the effects of the present invention are achieved.

  In the first step, the preform can be pressurized. For example, it is possible to exemplify pressurization for holding the preform from above and below, or preliminary pressurization for forming the preform into a desired shape. At this time, the pressure for pressurizing the preform is preferably 0 to 3 MPa, and more preferably 0.2 to 2 MPa.

  In the second step, the preform heated in the first step is formed into a target shape by pressurization. Preferably, after the surface temperature of the metal material in contact with the molding die exceeds 180 ° C. by heating in the first step, the preform is molded into a composite by pressing. In the second step, the preform is heated at the pressure P2 while being heated so that the surface temperature of the metal material exceeds 180 ° C., preferably 200 to 250 ° C. That is, the metal material heated in the first step is preferably supplied to the second step with a temperature exceeding 180 ° C., and is supplied to the second step with a temperature of 200 to 300 ° C. Is more preferable.

  The second step may be performed in a molding die different from the first step, but is preferably performed in the same molding die.

  The pressure P2 in the second step is preferably 3 to 30 MPa, more preferably 5 to 25 MPa. By molding by such pressure, even a complicated shape can be easily molded. The pressure P2 is preferably maintained in the above range until the preform is molded into a desired shape. After the preform is formed into the desired shape, the pressure may be reduced.

  In the second step and / or the third step, the edge of the preform may be hemmed or pressed. By such processing, the aesthetic appearance of the end portion of the metal composite is improved, and the bonding between the metal material and the cured resin layer becomes stronger. Such processing may be performed as an additional step after the third step.

  In the third step, the metal composite formed in the second step is cooled until the surface temperature of the metal material becomes 180 ° C. or lower under pressure P3. The time during which the metal composite is held at a temperature of 180 ° C. or lower in the third step is preferably within 10 minutes, more preferably within 5 minutes, and even more preferably within 3 minutes. Further, the pressure P3 is preferably equal to or higher than the pressure P2 and more preferably higher than the pressure P2 from the viewpoint of forcing warping and distortion due to cooling. Specifically, the pressure P3 is preferably 0 to 10 MPa, more preferably 3 to 5 MPa higher than the pressure P2, and the upper limit is not particularly limited. Considering overload, about 30 MPa is considered good.

  The first step, the second step, and the third step are preferably performed in the same molding die. Thereby, a metal composite can be manufactured with higher productivity and economy.

  In the second step and / or the third step, preferably, the thermosetting resin is cured to a cured state. For example, after the preform is formed into a desired shape and the metal composite is formed, the thermosetting resin can be cured by holding the metal composite in the molding die as it is. It is preferable to cure the thermosetting resin by holding the metal composite at a temperature of 180 ° C. or lower in the third step.

  The holding time for curing the thermosetting resin is not particularly limited, but is preferably as short as possible from the viewpoint of productivity, for example, preferably within 10 minutes, preferably within 3 minutes. More preferably, it is particularly preferably within 1 minute. From the viewpoint of the curing reaction, it is more preferable to hold the metal composite and cure the thermosetting resin so that the temperature of the sheet-like substrate is preferably 180 ° C. or lower, more preferably 160 ° C. or lower. By increasing the degree of curing in the first step, the holding time for curing in the second step and / or the third step can also be shortened.

  The manufacturing method according to the present embodiment may further include a step of after-curing the metal composite after the third step. When after-curing is performed, the time for holding the metal composite in the molding die for curing the thermosetting resin can be further shortened. The after-curing method may be any method that can cure the thermosetting resin. For example, the after-curing method can be performed by a method of holding the metal composite in a dryer or oven heated to a predetermined temperature.

  FIG. 1 is a schematic cross-sectional view illustrating an embodiment of a method for producing a metal composite. As shown in FIG. 1A, the molding die includes an upper molding die 11 and a lower molding die 12. The preform 10 has a sandwich structure in which a plate-like metal material 1 and a metal material 3 are respectively laminated on both surfaces of a sheet-like substrate 2.

  In the first step, the preform 10 is sandwiched between an upper molding die 11 and a lower molding die 12 as shown in FIG. The upper molding die 11 and the lower molding die 12 are heated so that the surface temperature exceeds 180 ° C. The metal material 1 is heated to a temperature exceeding 180 ° C. by contact with the upper molding die 11 and / or the lower molding die 12. The sheet-like base material 2 is heated via the heated metal material 1, and the curing reaction of the thermosetting resin of the sheet-like base material 2 is started to reach a semi-cured state.

  Next, the second step is performed using the same upper molding die 11 and lower molding die 12. In the second step, as shown in FIG. 1C, the preform 10 is pressurized by the upper molding die 11 and the lower molding die 12, and the preform 10 is deformed so as to follow the molding die. And it shape | molds in the metal composite 20 which has the resin cured layer 2a formed from the sheet-like base material 2. FIG.

  FIG. 2 is a schematic cross-sectional view illustrating another embodiment of a method for producing a metal composite. As shown in FIG. 2, the “forming” in the second step does not necessarily have to deform the metal material, and the plate-like metal materials 1 are bonded to each other via the sheet-like base material 2. Is also included in “molding”.

  FIG. 3 is a diagram showing an example of the relationship among temperature, time and pressure in the method for producing a metal composite. In FIG. 3, molding die temperatures T2 and T3 are the surface temperatures of the upper molding die and the lower molding die. In the first step, the surface temperature of the metal material in contact with the molding die heated to a temperature T2 exceeding 180 ° C. rises to the same level as T2. Along with this, the curing reaction of the thermosetting resin of the sheet-like substrate is started, and a semi-cured state is reached.

  Next, in the second step, the preform is pressurized and molded with a predetermined pressure. At this time, since the thermosetting resin is in a semi-cured state, the cured resin layer is formed along the metal material without excessively flowing the thermosetting resin even when pressurized.

  Continuing from the second step, the mold temperature is lowered to a temperature T3 of 180 ° C. or lower while maintaining the pressurized state. In the third step, the surface temperature of the metal material is maintained for a certain period of time in a state of T3, and the thermosetting resin is in a cured state.

  In the second step, the surface temperature of the metal material exceeds 180 ° C., and it is preferable that the time from when the temperature starts to drop until the surface temperature of the metal material reaches 180 ° C. or less is within 3 minutes.

  When the third step is completed, the upper and lower molding dies are opened, and the metal composite is removed.

(Metal composite)
The metal composite manufactured by the manufacturing method according to the present embodiment includes a metal material and a cured resin layer provided along the metal material. The cured resin layer is a layer formed by curing the thermosetting resin contained in the sheet-like substrate.

  According to the manufacturing method according to the present embodiment, a strong adhesion structure is formed between the metal material and the cured resin layer. This is because the surface of the metal material has a coarse or fine uneven shape. For example, the thermosetting resin is filled and cured, and the chemical bond strength with the metal material is enhanced by a curing reaction at a relatively high temperature.

  The adhesive strength between the metal material and the cured resin layer is preferably 10 MPa or more, and more preferably 20 MPa or more. These indicators indicate that the metal composite that combines metal materials or metal materials and other structural members through a cured resin layer has sufficient adhesive strength depending on the usage environment and application. Means.

  If the adhesive strength is 10 MPa or more, it has sufficient adhesive strength in applications where general adhesives are used, and has durability superior to metal composites using adhesives. If the adhesive strength is 20 MPa or more, it has sufficient adhesive strength in applications that are used in more severe environments, and has durability superior to a metal composite using a structural adhesive.

  The adhesive strength can be measured by a method such as a tensile adhesive strength test method of an adhesive according to JIS K 6849, for example. However, since the metal composite generally has a complicated shape, it is difficult to perform an adhesive strength test according to the standard. Therefore, by using an adhesive whose adhesive strength is known in advance, a part of the metal composite is cut out, both ends thereof are bonded to a jig, and an adhesive strength test is performed through the jig. A rough indication of whether the adhesive strength is superior or inferior to the adhesive strength of the adhesive can be obtained. That is, if broken within the adhesive layer, the adhesive strength of the metal composite is determined to be approximately higher than the adhesive strength of the adhesive. On the other hand, if the metal composite is broken by peeling, it is determined that the adhesive strength of the metal composite is approximately lower than the adhesive strength of the adhesive.

  Applications of the metal composite of the present invention include, for example, aircraft members, automobile members, two-wheeled vehicle members, marine members, mechanical mechanism members, civil engineering members, building material members, and electronic device members. Among them, it is preferably used for automobile members and electrical device members because of the effect of increasing productivity, and is particularly preferably used for housings of electronic devices because of its excellent effects of lightness, mechanical properties, heat dissipation and the like.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Example 1
(Preparation of thermosetting resin)
“Epicoat” 828, “Epicoat” 834, “Epicoat” 1001 (above, bisphenol A type epoxy resin, manufactured by Japan Epoxy Resins Co., Ltd.) and “Epicoat” 154 (phenol novolac type epoxy resin, Japan Epoxy Resin) Co., Ltd.), Dicy7 (dicyanamide, manufactured by Japan Epoxy Resin Co., Ltd.) as a curing agent, “OMICURE” 24 (2,4-toluenebis (dimethylurea), PIT Japan Ltd. as a curing accelerator These were mixed at a mass ratio shown in Table 1 to prepare a resin composition.

  Based on the method described in JIS K7121, the glass transition temperature (Tg) of the prepared resin composition was measured using a Pyris 1DSC (differential scanning calorimeter manufactured by PerkinElmer Instruments) at a heating rate of 10 minutes / minute. It calculated | required from the measured DSC curve. The intermediate point in the portion where the DSC curve shows a step-like change was taken as the glass transition temperature. In this measurement method, the Tg of the resin composition was 6 ° C., and the Tg saturated by curing was 138 ° C. That is, when Tg is in the range of 19 to 125 ° C., it can be said that the resin composition is in a semi-cured state.

  The relationship between the heating temperature and heating time of the prepared resin composition and Tg was determined. When the heating temperature was 130 ° C. or 150 ° C., the Tg change due to the heating time was measured. When the heating temperature was 130 ° C. and the heating time was 10 minutes, the Tg was 138 ° C., and the resin composition could be in a cured state. all right. The heating temperature here means the surface temperature of the heating plate when the resin composition is sandwiched and heated by a press device having a heating plate.

(Preparation of sheet-like substrate)
A resin film was prepared by applying the prepared resin composition on release paper using a reverse roll coater. The amount of resin per unit area of the resin film was 25 g / m ² .

Next, carbon fibers (Treka (registered trademark), T700SC-12K-50C, manufactured by Toray Industries, Inc., tensile strength) aligned in one direction in a sheet shape so that the fiber weight per unit area is 125 g / m ^2. Resin films were stacked from both sides of 4900 MPa and tensile modulus of 230 GPa), and heated and pressurized to impregnate the resin composition into carbon fibers to produce a unidirectional prepreg (continuous fiber reinforced prepreg (CF-PPg)). Four rectangular prepreg sheets having a predetermined size were cut out from the prepared prepreg. Laminating four prepreg sheets so that the direction of the cut long side of the prepreg sheet is 0 °, and the direction of continuous reinforcing fibers is a symmetrical configuration of [0 ° / 90 ° / 90 ° / 0 °], A sheet-like substrate having a thickness of 0.5 mm was produced. During the lamination, a K thermocouple was inserted between 90 ° layers of the prepreg base material.

  Using a press molding apparatus, a sheet-like base material was placed on a heating plate having a surface temperature of 130 ° C., and pressed at 1 MPa for 10 minutes while heating to obtain a molded product. When Tg of the obtained molded product was measured by the same method as described above, it was 137 ° C., and the molded product (resin composition) was in a cured state.

(Preform production)
As a metal material, an aluminum alloy plate (A5052) having a thickness of 0.5 mm whose surface was sandblasted was prepared. A large number of holes having an average pore diameter of 30 μm were observed on the surface of the aluminum alloy plate. This metal material and the above-mentioned sheet-like base material were laminated in the order of metal material / sheet-like base material / metal material to prepare a preform. During lamination, a K thermocouple was attached to the surface of one of the metal materials using a heat-resistant tape.

(Manufacture of metal composites)
A metal composite was produced by the following process including the first step, the second step, and the third step as shown in FIG.

[First step]
As shown in FIG. 1B, the preform was sandwiched between the upper molding die and the lower molding die, and held at a pressure of 0.5 MPa. The surface temperatures of the upper molding die and the lower molding die were both 220 ° C. The resin composition was semi-cured by holding in this state for about 1 minute. At this time, the surface temperature of the metal material was 215 ° C., and the temperature of the sheet-like substrate was 150 ° C. Based on the correlation between Tg and the heating temperature and heating time acquired in advance as described above, the Tg of the resin composition in the metal composite was estimated to be 115 ° C. Since this Tg is 82% with respect to the saturated Tg, it can be seen that the resin composition at the end of the first step is in a semi-cured state.

[Second step]
Subsequently, the preform was pressed at 10 MPa with the upper molding die and the lower molding die to mold a metal composite.

[Third step]
About 1 minute after starting the pressurization in the second step, the upper mold is cooled while flowing the cooling water to cool the upper mold and the lower mold until the surface temperature becomes 180 ° C. or lower. The set temperature of the mold and the lower molding die was changed to 150 ° C. The correlation between the amount of cooling water and the surface temperature of the molding die was confirmed in advance without the preform being disposed, and the amount of cooling water was adjusted based on this correlation. The surface temperature of the metal material became 180 ° C. or less after about 2 minutes from the start of cooling, and then pressurization was performed for about 1 minute.

[Demolding]
The mold was opened and the metal composite was removed from the mold. Metal materials constituting the obtained metal composite were firmly bonded to each other, and peeling by human power was difficult. There was no displacement between the two metal materials, the thickness of the metal composite was 1.5 mm, no sink marks or twists were observed, and no warpage or distortion occurred in the entire metal composite. It was 16 Mpa when the adhesive strength was measured by the method mentioned later about a metal composite. After the adhesion test, the resin composition adhered to the metal material was shaved and measured for Tg. It was 137 ° C., and it was confirmed that the resin composition at the end of the third step was in a cured state. It was.

(Example 2)
(Preform production)
As a metal material, a magnesium alloy plate (AZ31) having a thickness of 0.5 mm whose surface was subjected to sandblasting was prepared. A large number of holes having an average hole diameter of 50 μm were observed on the surface of the magnesium alloy plate. A preform was produced in the same manner as in Example 1 except that the metal material was changed to this magnesium alloy plate.

(Production of metal composite)
[First step]
As shown in FIG. 1B, the preform was sandwiched between the upper molding die and the lower molding die, and held at a pressure of 0.5 MPa. The surface temperature of both the upper molding die and the lower molding die was 210 ° C. The resin composition was semi-cured by holding in this state for about 1 minute. At this time, the temperature of the metal material was 210 ° C., and the temperature of the sheet-like substrate was 140 ° C. Based on the correlation between the heating temperature and the heating time and Tg, the Tg of the resin composition in the metal composite was estimated to be 108 ° C. Since this Tg is 77% with respect to the saturated Tg, it can be seen that the resin composition at the end of the first step is in a semi-cured state.

[Second step]
Subsequently, the preform was pressed at 15 MPa with the upper molding die and the lower molding die to mold a metal composite.

[Third step]
About 1 minute after starting the pressurization in the second step, the upper molding die and the lower molding die are cooled while cooling the upper molding die and the lower molding die to 180 ° C. or less by flowing cooling water. The set temperature of the side mold was changed to 150 ° C. The surface temperature of the metal material became 180 ° C. or less after about 2 minutes from the start of cooling, and then pressurization was performed for about 1 minute.

[Demolding]
The mold was opened and the metal composite was removed from the mold. There was no deviation between the two metal materials, the thickness of the metal composite was 1.5 mm, and the metal composite had an uneven shape. No surface defects such as wrinkles, cracks and tears were observed in the metal composite, and no warpage or distortion occurred in the entire metal composite. Metal materials of the obtained metal composite were firmly bonded to each other, and peeling by human power was difficult. When the adhesive strength of the metal composite was measured by the method described later, it was 18 MPa. After the adhesion test, the resin composition adhered to the metal material was shaved and measured for Tg. It was 137 ° C., and it was confirmed that the resin composition at the end of the third step was in a cured state. It was.

(Example 3)
As a metal material, an aluminum alloy plate (A5052) having a thickness of 0.5 mm and having a metal surface subjected to alumite treatment was prepared. A number of holes having an average hole diameter of 0.05 μm were observed on the surface of the aluminum alloy plate. A metal composite was produced in the same manner as in Example 1 except that the metal material was changed to this aluminum alloy plate, and its evaluation was performed.

Example 4
A resin film was prepared using the resin composition prepared in Example 1. The amount of resin per unit area of the resin film was 50 g / m ² . A metal composite was produced in the same manner as in Example 1 except that the sheet-like substrate was changed to this resin film, and evaluated.

(Example 5)
Using the sheet-like substrate and metal material produced in Example 1, a preform having a two-layer structure of metal material / sheet-like substrate was produced. In the first step, the surface temperature of the lower molding die was set to 150 ° C. A metal composite was produced in the same manner as in Example 1 except that this preform was used and the surface temperature of the lower molding die was evaluated.

(Example 6)
Using the same preform as in Example 1, about 30 seconds after the start of heating in the first step, pressurization in the second step was started, and about 30 seconds later, as the third step, The upper molding die and the lower molding die were cooled to 180 ° C. or less by flowing cooling water, and the set temperature of the upper and lower molding dies was changed to 170 ° C. About 1 minute after the surface temperature of the metal material started cooling, it became a state of 180 ° C. or lower, and then pressurization was performed for about 1 minute. Thereafter, the molding die was opened, and the metal composite was taken out from the molding die. The taken-out metal composite was put into a hot air oven adjusted to an atmospheric temperature of 150 ° C., and after-curing was performed for 10 minutes. The obtained metal composite was evaluated in the same manner as in Example 1.

(Example 7)
As the benzoxazine resin, a Fa type benzoxazine resin (manufactured by Shikoku Kasei Kogyo Co., Ltd.) is used, and as the acid catalyst, DY9577 (manufactured by Huntsman Advanced Materials Co., Ltd., boron trichloride octylamine complex) is used. The mixture was mixed at a mass ratio shown in FIG. A metal composite and an electronic device casing were manufactured under the same conditions as in Example 1 except that this resin composition was used as a thermosetting resin for forming a sheet-like substrate. From the result of measuring the viscosity of the resin using a viscometer, the degree of curing of the resin was calculated, and it was found that the resin was in a semi-cured state in the first step.

(Example 8)
Phenolite (registered trademark) 5010 (manufactured by DIC Corporation, resol type phenolic resin) was prepared as a phenolic resin, and was used as a thermosetting resin for forming a sheet-like substrate. It was.

Example 9
As a metal material, a 0.2 mm-thick titanium alloy plate (Ti-6AL-4V) having a metal surface subjected to sandblasting was used. A metal composite and an electronic device casing were manufactured and evaluated in the same manner as in Example 1 except that the surface temperature of the molding die was 240 ° C. and the molding pressure was 15 MPa. A large number of holes with an average pore diameter of 15 μm were observed on the surface of the metal plate. Production conditions and evaluation results are shown in Table 2.

(Example 10)
A metal composite and an electronic device casing were manufactured and evaluated in the same manner as in Example 1 except that the upper and lower molding die temperatures were 190 ° C. In addition, the surface temperature of the metal material at the time of a 1st process was 185 degreeC. Production conditions and evaluation results are shown in Table 2.

(Example 11)
As shown in FIG. 5A, an aluminum alloy (A5052) having an L-bending process of about 90 ° was prepared as shown in FIG. The same sheet-like base material as in Example 1 was arranged as shown in FIG. 5B, and the L-bent portion was bent into a preform. Except for these, molding was performed in the same manner as in Example 1. By pressurizing the molding die, the bent L bent part was flattened, and the end was hemmed to obtain a metal composite.

(Example 12)
The same procedure as in Example 1 was performed except that an industrial pure aluminum plate (A1100) was used as the metal material. Production conditions and evaluation results are shown in Table 2.

(Example 13)
As Example 9, except that industrial pure titanium (KS40) was used as the metal material. Production conditions and evaluation results are shown in Table 2.

(Comparative Example 1)
(Preform production)
A metal composite was produced in the same manner as in Example 1 except that the composition of the thermosetting resin was changed to the mass ratio shown in Table 2. Using a press molding apparatus, a sheet-like substrate was placed on a heating plate having a surface temperature of 130 ° C., and was pressurized at 1 MPa for 10 minutes while being heated. It was 75 degreeC when Tg of the obtained molded article was measured by the method similar to the above. Since this Tg is 52% with respect to the saturated Tg, it can be seen that the resin composition is in a semi-cured state.

(Manufacture of metal composites)
[First step]
As shown in FIG. 1B, the preform 10 was sandwiched between the upper molding die and the lower molding die, and held at a pressure of 0.5 MPa. At this time, the surface temperature of both the upper molding die and the lower molding die was 220 ° C., and the temperature of the sheet-like substrate was 150 ° C. In this state, the resin composition was reacted for about 1 minute. Based on the correlation between Tg and the heating temperature and heating time acquired in advance as described above, the Tg of the resin composition in the metal composite was estimated to be 14 ° C. Since this Tg is 6% with respect to the saturated Tg, the resin composition at the end of the first step has not reached a semi-cured state.

[Second step]
Subsequently, the preform was pressurized at 10 MPa with the upper molding die and the lower molding die. At this time, a large amount of the resin composition flowed from between the molding dies.

[Demolding]
After cooling for about 3 minutes without cooling in the third step, when the mold was opened, the metal material and the metal material were misaligned, and the entire metal composite was warped, and the metal Part of the sheet-like base material protruded from between the materials, and the target metal composite was not obtained. Furthermore, when the metal composite was taken out, the metal material was fixed to the molding die, and it was difficult to remove the composite. Therefore, it was impossible to measure the adhesive strength described later.

(Comparative Example 2)
As shown in FIG. 1B, a preform similar to that in Example 2 was sandwiched between the upper molding die and the lower molding die, and held at a pressure of 0.5 MPa. The surface temperature of both the upper mold and the lower mold was 130 ° C. Except for this, a metal composite was produced in the same manner as in Example 2 and evaluated. Production conditions and evaluation results are shown in Table 2.

  In the obtained metal composite, the two metal materials were misaligned, and the thermosetting resin leaked slightly from between the metal materials. A wrinkle was observed in the squeezed portion of the unevenness, and a surface crack occurred in the deeply squeezed portion. The metal material was peelable by human power.

  The production conditions and evaluation results in the above Examples and Comparative Examples are summarized in Tables 1 and 2.

(Measurement of average pore diameter on metal surface)
The surface of the metal used as the metal material was photographed at a magnification of 100 times using an ultra-deep color 3D shape measurement microscope VK-9500 (controller part) / VK-9510 (measurement part) (manufactured by Keyence Corporation). An arbitrary pore diameter D _(n) (n = 1 to 100) formed on the metal surface was measured from the photographed image using the analysis application VK-H1A9, and an average pore diameter was obtained.

(Measurement of adhesive strength of metal composite)
A 40 mm square test piece was cut out from the smooth part of the manufactured metal composite, both surfaces were roughened using sand blasting, and the oil was wiped off with acetone, followed by structural epoxy resin (Chemit TE manufactured by Toray Fine Chemical Co., Ltd.). -220) was used to bond a 40 mm cubic aluminum alloy block with a 10 mm diameter through hole. Similarly, an aluminum alloy block was adhered to the other surface to produce a sample for measuring adhesive strength shown in FIG. Tensile test equipment "Instron" (registered trademark) 5565 type universal material testing machine (Instron Japan Co., Ltd.) fixed at the top and bottom and through holes of aluminum alloy block through pins, and pulling speed Evaluation was performed with the number of evaluation samples n being 5 at 1.6 mm / min. The bond strength S of the metal composite was calculated from the obtained value and the following formula (1). If the bond strength obtained by calculation is 10 MPa or more, it is difficult to peel off by human power.
S = P / A (1)
S: Adhesive strength [MPa], P: Maximum load [N], A: Sample cross-sectional area [mm ² ]

DESCRIPTION OF SYMBOLS 1 Metal material 2 Sheet-like base material 2a Resin hardening layer 3 Metal material 4 One member 5 The other member 6 Adhesive 7 Aluminum alloy block 8 L-shaped metal material 10 Preform 11 Upper molding die 12 Lower side Mold 20 Metal composite (test piece)
21 Upper mold 22 Lower mold

Claims (20)

A sheet-like substrate containing a thermosetting resin that is at least one selected from the group consisting of an epoxy resin, a phenol resin, a benzoxazine resin, and an unsaturated polyester resin, and disposed or laminated so as to be in contact with the sheet-like substrate Forming a preform comprising a metal material by heating and pressurizing, and producing a metal composite comprising the metal material and a cured resin layer provided along the metal material,
A first step of placing the preform in a molding die and heating until the surface temperature of the metal material exceeds 180 ° C., and semi-curing the thermosetting resin;
A second step of forming the preform heated in the first step into a metal composite by applying pressure P2,
A third step of cooling the metal composite formed in the second step until the surface temperature of the metal material is 180 ° C. or lower under pressure P3;
A method for producing a metal composite.   The method for producing a metal composite according to claim 1, wherein the sheet-like substrate is one in which the thermosetting resin contained therein is cured when heated at 130 ° C for 10 minutes. The manufacturing method of the metal complex of Claim 1 or 2 which heats until the surface temperature of a metal material becomes 200-300 degreeC in a 1st process.   The manufacturing method of the metal complex in any one of Claims 1-3 with which the shaping die at the time of arrange | positioning a preform has a surface temperature of 200-300 degreeC in a 1st process.   The manufacturing method of the metal complex in any one of Claims 1-4 which performs a 1st process, a 2nd process, and a 3rd process within the same molding die.   The manufacturing method of the metal complex in any one of Claims 1-5 in which a thermosetting resin will be in a hardening state in a 2nd process and / or a 3rd process.   The method for producing a metal composite according to any one of claims 1 to 6, wherein the pressure P3 is equal to or higher than the pressure P2.   The manufacturing method of the metal complex in any one of Claims 1-7 whose pressure P2 is 3-30 Mpa.   The method for producing a metal composite according to any one of claims 1 to 8, wherein the time until the surface temperature of the metal material drops from a temperature exceeding 180 ° C to 180 ° C or less is within 3 minutes.   The method for producing a metal composite according to any one of claims 1 to 9, wherein, in the second step and / or the third step, the edge of the preform is hemmed or pressed.   The method for producing a metal composite according to any one of claims 1 to 10, further comprising a step of after-curing the metal composite after the third step.   The manufacturing method of the metal composite body in any one of Claims 1-11 whose sheet-like base material is a prepreg formed by a fiber base material being impregnated with a thermosetting resin.   The method for producing a metal composite according to claim 1, wherein a curing accelerator is added to the thermosetting resin.   The method for producing a metal composite according to any one of claims 1 to 13, wherein the metal material is a plate-like body having a thickness of 0.1 to 1 mm.   The method for producing a metal composite according to any one of claims 1 to 14, wherein the metal material is physically, chemically or electrically roughened on the surface in contact with the sheet-like substrate.   The metal material is a method for producing a metal composite according to any one of claims 1 to 15, wherein a plurality of 0.01 to 100 µm holes are formed on a surface in contact with the sheet-like base material.   The method for producing a metal composite according to any one of claims 1 to 16, wherein the metal forming the metal material is at least one selected from the group consisting of an aluminum alloy, a magnesium alloy, and a titanium alloy.   The method for producing a metal composite according to any one of claims 1 to 17, wherein the preform has a sandwich structure in which metal materials are laminated on both sides of a sheet-like substrate or a laminate thereof.   The manufacturing method of the metal complex in any one of Claims 1-18 whose adhesive strength of the metal material and resin hardened layer in a metal complex is 10 Mpa or more.   An electronic device housing comprising a metal composite obtainable by the method according to claim 1.

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