JP5906583B2 - Method for producing metal-based member - Google Patents

Description

  The present invention relates to a metal member made of a metal material having a granular protrusion on the surface and a method for manufacturing the metal member.

  Various surface treatments are performed on the surface of the metal-based member according to the function required for the member. For example, there are surface modification treatments such as carburizing treatment, nitriding treatment, soft nitriding treatment, and formation of a surface coating excellent in wear resistance, corrosion resistance and the like. Furthermore, recently, in order to improve adhesion and water repellency, surface treatment for forming fine irregularities on the surface of the substrate has also been performed.

  There are various methods for forming such fine irregularities, but the following patent document proposes a method by ion bombardment treatment or plasma treatment. In particular, Patent Documents 2 and 3 also propose to use atmospheric pressure plasma processing that can reduce production costs.

Japanese Patent No. 3453033 International Publication WO2005 / 097396 JP 2009-175729 A JP 2010-202955 A JP 2010-162528 A

  However, in the above-mentioned patent documents, even if plasma (ions) is used, the surface is merely cleaned and fine irregularities are formed by etching. Even when atmospheric pressure plasma is used, the irradiation target is a resin material, and the unevenness is merely formed by breaking the bonds constituting the resin.

  This invention is made | formed in view of such a situation, and provides the metal-type member which has the processus | protrusion fundamentally different from the convex part formed by the conventional etching etc. on the metal surface, and its manufacturing method. Objective.

As a result of extensive research and trial and error, the present inventor has radiated atmospheric pressure plasma onto the surface of a metal material made of a specific metal element (for example, Cu). It was newly found that protrusions made of an oxide (for example, Cu ₂ O) were raised. By developing this knowledge, the present invention described below has been completed.

《Metallic material》
(1) The metal-based member of the present invention is a metal-based member made of a metal material including a specific transition metal element capable of generating a stable oxide and a metastable oxide having different oxidation numbers, and the metal material is wherein obtained by introducing oxygen active species to the surface adhered with fatty acid or fatty acid salt with not coated with a stable oxide, having a granular protrusions consisting of oxides of the specific transition metal element that protrudes from the surface It is characterized by that.

(2) According to the metal-based member of the present invention, since the granular protrusions are present on the surface of the metal material, it is possible to improve the bonding interface between the metal material and the other material, improve water repellency or oil repellency, and the like. Details such as the formation mechanism of such granular protrusions and the mechanism of the effects brought about by the granular protrusions are under investigation and are not necessarily clear at present. However, as a result of intensive studies by the present inventors, the metal material on which such granular protrusions are formed includes a specific transition metal element capable of generating a stable oxide and a metastable oxide having different oxidation numbers. In addition, it is known that the granular protrusion is made of an oxide of the specific transition metal element.

<< Method for producing metal-based member >>
(1) The present invention can be grasped not only as the metal-based member but also as a manufacturing method thereof. That is, the present invention includes an oxygen introduction step of introducing an oxygen active species into the surface of the metal material that is not coated with the stable oxide and to which a fatty acid or a fatty acid salt is adhered , and the metal member described above is obtained. The manufacturing method of the metal-type member characterized by these may be sufficient.

(2) The reason why the above-described granular protrusions are formed by the manufacturing method of the present invention is not necessarily clear, but at present, it is considered as follows. When oxygen active species (oxygen radicals) are partially introduced into the surface of a metal material that is not coated with a stable oxide, oxides of this specific transition metal element (this oxidation) The product is referred to as a “specific oxide”). As described above, it is considered that the specific oxide is partially generated on the surface of the metal material and is raised, thereby creating a granular protrusion. And the form (especially size) of a granular protrusion is considered to be decided according to the production | generation process or aggregation form of the specific oxide.

  Incidentally, the generation of such a specific oxide (and its agglomeration) is caused by a highly active and high energy oxygen active species, so that the time required for creating the granular protrusions is short. Therefore, according to the manufacturing method of the present invention, a metal-based member can also be manufactured efficiently.

<Others>
(1) The stable oxide referred to in the present invention is generally the most stable oxide among the oxides of the specific transition metal element, and is usually an oxide having the largest oxidation number of the specific transition metal element. is there. A metastable oxide is an oxide that is unstable or can be changed to a stable oxide rather than a stable oxide. Usually, an oxidation number of a specific transition metal element is smaller than that of a stable oxide. It is a thing.

(2) Unless otherwise specified, “x to y” in this specification includes a lower limit value x and an upper limit value y. A range such as “a to b” can be newly established with any numerical value included in various numerical values or numerical ranges described in the present specification as a new lower limit value or upper limit value.

It is a schematic diagram which shows the mode of a plasma processing. Sample No. It is a photograph which shows the AFM image of the 1 plasma processing surface. Sample No. It is a photograph which shows the AFM image of the plasma processing surface of 2. FIG. Sample No. It is a photograph which shows the AFM image of the plasma processing surface of C1. Sample No. It is a photograph which shows the SEM image of the plasma processing surface of 2. FIG. Sample No. 4 is a photograph showing an SEM image of a plasma treated surface of No. 4; Sample No. It is a photograph which shows the TEM image of the plasma processing surface of 2. FIG. Sample No. It is the result of having observed the to-be-processed surface of 2 by XPS. Sample No. 4 is a result of XPS observation of the surface to be processed. It is the result of the long wave side of a plasma emission spectroscopic analysis. It is the result of the short wave side of a plasma emission spectroscopic analysis. It is a schematic diagram which shows the mode of laser joining. It is a photograph which shows the AFM image of the metal substrate surface which oxidized (100 degreeC x 2 hours). It is a photograph which shows the AFM image of the metal substrate surface which oxidized (180 degreeC x 2 hours). Sample No. It is a photograph which shows the wettability of the plasma processing surface of 2. FIG. It is a photograph which shows the wettability when a silane coupling agent is apply | coated to the surface. It is a photograph which shows the wettability of the buff grinding | polishing surface (surface to be processed before the plasma processing of sample No. 4). It is a photograph which shows the wettability when a silane coupling agent is apply | coated to the surface. Is a photograph showing the wettability of the Cu ₂ O surface (surface to be processed before plasma treatment of the sample No.C2).

m Metal substrate (metal material)
r Acrylic resin plate (resin material)

  The present invention will be described in more detail with reference to embodiments of the invention. One or two or more components arbitrarily selected from the present specification may be added to the above-described configuration of the present invention. The contents described in this specification can be applied not only to the metal-based member according to the present invention but also to the manufacturing method thereof. A component related to a manufacturing method can be a component related to an object if understood as a product-by-process. Note that which embodiment is the best depends on the target, required performance, and the like.

《Metallic material》
(1) Metal material The metal material may be a pure metal, an alloy, a composite material, or the like as long as it contains a specific transition metal element capable of generating a stable oxide and a metastable oxide having different oxidation numbers. Examples of such a specific transition metal element include Cu, Fe, and Mn. For example, when the specific transition metal element is Cu, the oxidation number is +1 or +2, and copper (I) (Cu ₂ O) which is a metastable oxide or copper (II) (CuO) which is a stable oxide, respectively. ) Is generated. When the specific transition metal element is Fe, the oxide becomes +2 or +3, and iron (II) (FeO) which is a metastable oxide or iron (III) (Fe ₂ ) which is a stable oxide, respectively. O ₃ ) or iron oxide (II, III) (Fe ₃ O ₄ ) is produced.

(2) Granular protrusion A granular protrusion consists of an oxide (specific oxide) of the specific transition metal element raised from the surface of the metal material. The specific oxide may be a metastable oxide, a stable oxide, or a composite oxide in which they are combined. For example, if the specific transition metal element is Cu and there is no oxide (oxide film) on the surface of the metal material, the specific oxide constituting the granular protrusions can be made of Cu ₂ O. When an oxide film made of Cu ₂ O is formed on the surface of the metal material, the specific oxide can be Cu ₂ O or CuO, but is considered to be mainly Cu ₂ O.

Further, when the specific transition metal element is Fe and there is no oxide (oxide film) on the surface of the metal material, the specific oxide can be composed of FeO. If an oxide film made of FeO is formed on the surface of the metal material, the specific oxide can be FeO, Fe ₃ O ₄ or Fe ₂ O ₃ , but is considered to be mainly FeO.

  The granular protrusions according to the present invention are not convex portions formed by etching or the like on the surface of the metal material, but are formed so that the oxide is generated (and further aggregated) on the surface of the metal material. . There is no limitation on the height difference between the granular protrusions and the periphery thereof. However, according to the research of the present inventor, it is known that the granular protrusion is a fine convex part having a height difference of about 10 to 400 nm, further about 15 to 350 nm.

  The surface of the metal material surrounding the granular protrusions may be flat or wavy. In addition, the surface portion of the metal material surrounding the granular protrusions may be a single element of a specific transition metal element or the like, or an oxide similar to the granular protrusion, but is usually considered to be in a metal (including alloy) state before oxidation. It is done.

<< Method for producing metal-based member >>
(1) Oxygen introduction process The granular protrusion which concerns on this invention is created by making an oxygen active species adhere or introduce | transduce (partly) to the surface of the metal material which is not coat | covered with the stable oxide. This oxygen active species can be obtained, for example, by a plasma supply process for supplying plasma into an oxygen atmosphere. Plasma sources at this time include inert gas, nitrogen, oxygen, chlorofluorocarbon (CFC) compound gas, hydrocarbon compound gas, etc., but helium, neon, argon, krypton, xenon, etc. in terms of low reactivity Inert gases, particularly argon gas, are preferred.

  The oxygen atmosphere for supplying plasma preferably has an oxygen concentration (% by volume) of 1% or more, 10% or more, and more preferably 15% or more. If the oxygen concentration is too low, sufficient oxygen active species are not generated, and it becomes difficult to efficiently create granular protrusions. The upper limit value of the oxygen concentration is not particularly limited, but if the oxygen concentration is excessive, the cost is increased, and an oxide (film) is easily formed on the entire surface of the metal material, which is thought to hinder the creation of granular protrusions. . Therefore, the oxygen concentration is preferably 50% or less, more preferably 30% or less.

  The oxygen atmosphere may be an atmospheric pressure atmosphere, and at this time, the plasma supply process is an atmospheric pressure plasma supply process. By using atmospheric pressure plasma, production facilities can be simplified and productivity can be improved, and as a result, the manufacturing cost of metal-based members can be reduced. This atmospheric pressure plasma is obtained, for example, by atmospheric pressure plasma glow discharge, atmospheric pressure jet plasma, atmospheric pressure plasma torch, atmospheric pressure surface dielectric barrier discharge, or the like.

(2) Surface to be treated of metal material It is preferable that a fatty acid or a fatty acid salt (hereinafter simply referred to as “fatty acid”) adheres to the surface (surface to be treated) of the metal material into which oxygen active species are introduced. By the presence of this fatty acid, the specific oxide and thus the granular protrusions are easily generated on the surface to be treated. Although this detailed mechanism is not clear, O contained in a carbonyl group, carboxyl group, hydroxyl group, or the like partially present in a fatty acid contributes to the formation of a partial specific oxide on the surface to be treated of a metal material. It is thought that. In other words, the fatty acid coating is an oxidation-inhibiting coating that suppresses oxidation of the entire treated surface of the metal material or selective oxidation induction that selectively generates a specific oxide on the treated surface of the metal material. It is thought to act as a coating.

  Further, it is preferable that the surface to be treated of the metal material is subjected to machining such as cutting, polishing, buffing, or the like. As a result, the specific oxide, and thus the granular protrusions, are easily generated partially on the surface to be processed. Although this detailed mechanism is not clear, it is considered that defects (for example, dislocations) and distortion introduced into the surface to be processed of the metal material by machining have an influence. That is, a specific oxide serving as a nucleus of the granular protrusion is generated starting from a defect or the like formed on the surface to be processed of the metal material. Then, it is considered that the temperature rise of the surface to be processed and the strain energy on the surface to be processed become a driving force, and it becomes easy to create granular projections in which specific oxides that are the cores aggregate.

<Uses of metal-based members>
The metal-based member of the present invention can be used not only as a substitute for the conventional product but also as a new functional member because the metal-based member of the present invention can be used regardless of its use, and exhibits characteristics that are not found in conventional members.

(1) As an example of the metal-based member of the present invention, there is a composite member obtained by melting and joining a resin material to a metal material. According to this composite member, the metal material and the resin material can be mechanically and firmly joined to each other by the anchor effect or the like via the granular protrusions formed on the surface of the metal material. For this reason, it becomes possible to obtain the composite member which does not use an adhesive etc. efficiently at low cost.

  Further, since the granular protrusions according to the present invention are very fine, it is possible to maintain the gloss of the surface of the metal material as it is without affecting the appearance of the metal material. When a transparent resin material is joined to such a metal material, a composite member to which the function of the resin material is added can be easily obtained while maintaining the gloss and appearance of the metal material.

By the way, the properties required for the bonding interface between the metal material and the resin material are different depending on the bonding strength of the composite member, the material of the metal material or the resin material, the surface roughness, etc., and thus cannot be generally described. However, according to the inventor's study, the granular protrusions at the joint interface have, for example, a protrusion density of 25 pieces / μm ² or more, further 50 pieces / μm ² or more, and a protrusion height (height difference) of 30 to 400 nm. It is preferable in it being 100-350 nm. In particular, such a granular protrusion is preferable when an acrylic resin (resin material) is bonded to a copper plate (metal material).

  The joining of the metal material and the resin material can be performed, for example, by a heating process in which laser light that passes through the resin material is irradiated from the resin material side to the metal material, and at least the vicinity of the joining interface of the metal material is heated. At this time, it is conceivable to heat the resin material side in the vicinity of the bonding interface. However, heating the resin material side tends to cause foaming, carbonization, and the like, which is not preferable. Therefore, it is preferable to heat the metal material side so that the resin material softens or melts at the bonding interface. In addition, if the resin material is bonded only to one side of the metal material, only the vicinity of the bonding interface of the metal material may be heated, and if the resin material is bonded to both surfaces of the metal material, the entire metal material May be heated.

  As described above, in the composite member according to the present invention, the metal material and the resin material are mechanically joined basically by the anchor effect or the like accompanying the softening or melting of the resin material. Therefore, the resin material may be either a thermoplastic resin or a thermosetting resin as long as it is softened or melted by heating at the time of joining. However, the metal element (M) in the metal material is bonded to the carbon (C) in the resin material via oxygen (O) or nitrogen (N) (M-O-C- or M-N-C-). Can do. In this case, the metal material and the resin material are not only mechanically bonded but also chemically bonded, and both are bonded more firmly. Therefore, the resin material bonded to the metal material preferably contains oxygen (O) constituting a carbonyl group, a carboxyl group, a hydroxyl group or the like, or nitrogen (N) constituting an amino group or the like.

(2) The surface of the metal material having the granular protrusions according to the present invention can exhibit excellent water repellency or oil repellency. Furthermore, when a coating material that lowers the surface energy is provided on the surface of the metal material, the water repellency is further improved. Examples of such a covering material include a silane coupling agent and a fluororesin coating agent. These coating materials preferably have a water contact angle of, for example, 5 ° or more. The surface energy of the covering material is preferably 40 mN / m or less, for example. The surface energy of the coating material is obtained by obtaining the contact angle from two or more solvents using a contact angle meter. For example, the surface energy is specified using two types of liquids with known surface energy, such as water and methylene iodide.

In this case, the protrusion density is preferably 10 pieces / μm ² or more, further 25 pieces / μm ² or more, and the protrusion height (height difference) is preferably 10 to 200 nm, more preferably 50 to 150 nm.

  Such water repellency is evaluated by wettability on the surface of the metal material. The wettability is specified by a contact angle (wet angle) formed between the fluid and the interface of the metal material. As the fluid state on the surface of such a metal material, a Wenzel mode and a Cassie mode can be considered. The Wenzel mode is a state in which liquid enters the bottom of the concavo-convex structure formed on the surface of the metal material, and the Cassie mode does not allow liquid to enter the bottom of the concavo-convex structure formed on the surface of the metal material by the intervention of air or the like. In this state, the liquid is supported by the tip of the convex portion of the concave-convex structure. The water repellency referred to in the context of the present invention is believed to be based on the Cassie mode.

The present invention will be described more specifically with reference to examples.
<Production of sample>
(1) Test material A plate material (metal material) made of oxygen-free copper was used as a test material. The specimen was mirror-finished by buffing (abrasive: alumina / particle size 0.05 mm). Thereby, the surface roughness was set to Ra = 0.04 and Rz = 0.23 (JIS). This was immersed in a hexadecane solution (10 ⁻⁵ mol / L) of stearic acid (fatty acid) to adhere stearic acid to the surface of the test material. For comparison, a test material to which stearic acid was not attached was also prepared.

(2) Plasma treatment (oxygen introduction process, plasma supply process)
FIG. 1 shows a state in which plasma is irradiated on the surface (surface to be treated) of each test material. The plasma gun used here is an alternating current excitation type (μ-AP manufactured by NU Eco-Engineering). The processing conditions at this time were plasma gas: argon gas, gas inflow: 4 L / min, and interelectrode voltage: 80V. The distance (irradiation distance) from the electrode exit of the plasma gun to the surface to be processed of the test material was 5 mm.

  However, the atmosphere and processing time for plasma treatment were changed as shown in Table 1 for each specimen. The “atmospheric pressure” atmosphere shown in Table 1 is temperature: room temperature, humidity: 40%, oxygen concentration: 17.4%. In addition, an “argon” atmosphere is formed by using a container to block the atmosphere, and pressure: atmospheric pressure, temperature: room temperature, and oxygen concentration: less than 0.01%.

  The plasma generated in the plasma gun was ejected outside the electrode along the gas flow, and plasma treatment was performed to irradiate the test material to obtain each sample shown in Table 1 (plasma supply process).

<< Observation and measurement >>
(1) FIGS. 2A to 2C, FIGS. 3A to 3B, and FIG. 4 show photographs obtained by microscopic observation of the surface to be treated (plasma treated surface) after the plasma treatment of each sample. 2A to 2C are sample Nos. FIGS. 3A to 3B are AFM images obtained by observing plasma processing surfaces of 1, 2 and C1 with an atomic force microscope (AFM). FIGS. 4A and 4B are SEM images obtained by observing the plasma-treated surfaces of 2 and 4 with a scanning electron microscope (SEM), respectively. It is the TEM image which observed the plasma processing surface of 2 with the transmission electron microscope (TEM).

(2) Sample No. With respect to the granular protrusions formed on the plasma treatment surfaces 1 to 3, the protrusion diameter (diameter), protrusion height (height difference) and protrusion density were measured, and each average value is shown in Table 1. The projection diameter was obtained by image analysis of the AFM image and searching for the boundary between the projection and the base flat portion from the cross-sectional curve. The protrusion height was measured by obtaining the difference between the apex of the protrusion shape and the base flat portion from the cross-sectional boundary of the AFM image, and the arithmetic average value of 1 μm square of the AFM image was calculated. The protrusion density was also obtained by image analysis of the AFM image, binarizing the height information, and counting protrusions of 1 μm square.

(3) Sample No. The element concentration ratio (component composition) of region 1, region 2 and region 3 shown in the TEM image (FIG. 4) of the plasma treated surface 2 was measured by energy dispersive X-ray spectroscopy (EDX). The results are shown in Table 2. Region 1 in FIG. 4 is a cross section obtained by cutting the protrusion with a focused ion beam (FIB), and regions 2 and 3 are portions without protrusions.

(4) Sample No. observed by X-ray photoelectron spectroscopy (XPS). Auger spectra (Cu-LMM1s) of the surfaces to be treated 2 and 4 are shown in FIGS. 5A and 5B, respectively.

<Evaluation>
(1) Creation of granular protrusions As is apparent from the photographs shown in Table 1 and FIGS. 2A to 2C and FIGS. 3A and 3B, by subjecting a sample having a stearic acid film formed on the surface to be processed to atmospheric pressure plasma treatment, It was found that a surface with a lot of fine granular protrusions was obtained.

  In particular, Sample No. As can be seen from FIGS. 1 to 3 and FIGS. 2A, 2B and 3A, it was also found that a large number of granular protrusions were created in a short plasma treatment of about 15 to 60 seconds. It was also found that the longer the plasma treatment time, the smaller the number (density) of the granular protrusions itself, but each granular protrusion grew and increased in size.

  The reason why such a phenomenon occurs is not clear, but at present, it is considered as follows. First, within a short time immediately after the start of the plasma treatment, the oxygen active species reaches the surface to be treated of the metal material, and an oxide (specific oxide) serving as a nucleus is generated. As the plasma treatment proceeds, the surface to be treated is heated and its temperature rises. As the temperature rises, the specific oxide moves and aggregates, and it is considered that the protrusions have grown to a suitable size. In addition, it is considered that a fine specific oxide serving as a nucleus is generated starting from defects such as dislocations introduced into the surface to be processed during mirror finishing.

  Sample No. in Table 1 As is apparent from C1 and FIG. 2C, it was found that the granular protrusions were not created even when the plasma treatment was performed in an argon atmosphere substantially free of oxygen. In other words, it can be seen that it is necessary to perform plasma treatment in an oxygen atmosphere (atmospheric pressure atmosphere) in order to create granular protrusions.

(2) Composition of granular protrusion From FIG. 4 and Table 2, it was found that the granular protrusion (part of region 1) was mainly composed of Cu ₂ O (metastable oxide). It was also found that the flat portions where no granular protrusions were formed (regions 1 and 2) were hardly oxidized (that is, made of Cu).

(3) Effect of stearic acid film Sample No. 1 in Table 1 As is clear from FIGS. 1 and 4 and FIGS. 3A and 3B, fine specific oxides (granular protrusions) can be formed without the stearic acid coating, but plasma treatment is applied to the surface to be treated with the stearic acid coating. It turns out that many granular protrusions of suitable size are created by applying.

  This can also be seen from the XPS analysis results shown in FIGS. 5A and 5B. That is, sample no. When a stearic acid film is present on the surface to be treated as shown in FIG. 2 (FIG. 5A), a Cu peak appears on the plasma treated surface. In contrast, sample no. When there is no stearic acid coating as in FIG. 4 (FIG. 5B), no Cu peak appears on the plasma treated surface. This is because, when there is a stearic acid film, unoxidized Cu remains on the surface to be processed, but when there is no stearic acid film, the entire surface to be processed is oxidized and it is difficult to generate scattered granular projections. Means.

Further, as can be seen from FIG. 5A and FIG. 5B, the Cu ²⁺ peak is hardly ^observed before and after the plasma treatment. From this, it was found that the oxide produced on the surface to be treated by the (atmospheric pressure) plasma treatment was substantially Cu ₂ O (metastable oxide) regardless of the presence or absence of the stearic acid coating.

(4) Oxygen active species (oxygen radical)
As described above, the creation of granular protrusions is affected by the plasma treatment atmosphere. Therefore, the results of plasma emission spectroscopic analysis in the case of an atmospheric pressure atmosphere (oxygen concentration: 17.4%) and the case of an argon atmosphere (oxygen concentration: less than 0.01%) are shown in FIGS. 6A and 6B. From these, it was found that in the atmospheric pressure atmosphere, peaks not observed in the argon atmosphere were detected, and oxygen radicals (O ^* ) and nitrogen oxide radicals (NO ^* ) were generated. In particular, the peak of oxygen radical (oxygen active species) was prominent. From this, it is considered that the granular protrusions are created by oxygen radicals (O ^* ).

<Composite material>
(1) Manufacture As an example of the metal-based member of the present invention, as shown in FIG. 7, an acrylic resin plate (resin material) r is laser-bonded to a metal substrate (metal material) m made of non-oxide copper having granular protrusions. The composite member was examined. The laser beam was applied to the bonding interface (side with the granular protrusions) of the metal substrate m to heat the metal substrate m in the vicinity of the bonding interface (heating process). At this time, the metal substrate m and the acrylic resin plate r were sandwiched between the glass plate G1 and the acrylic plate G2 with a pressure of 0.4 MPa, and laser light was irradiated from the glass plate G1 side.

  The metal substrate m used here is φ10 mm × thickness 2 mm, the acrylic resin plate r is 10 mm × 10 mm × 3 mm, the laser beam has a wavelength of 920 nm, a spot diameter at the bonding interface: 2.0 mm, a laser output: 25 W, an irradiation time: 30 Seconds.

(2) Evaluation Sample No. in Table 1 It was found that the metal substrate m having the same plasma treated surface as 1 was firmly bonded to the acrylic resin plate r. Sample No. The metal substrate m having the same plasma treated surface as 3 could be bonded to the acrylic resin plate r, but peeled off by impact.

  For reference, it was evaluated whether or not other metal substrates m were bonded to the acrylic resin plate r by similar laser bonding. The prepared metal substrate m is Sample No. This is the same as that before the plasma treatment corresponding to 4, C2 and C3. In addition, a non-oxidized copper plate that was sandblasted (Ra = 0.74, Rz = 0.04) was also prepared. None of the former three metal substrates m were bonded to the acrylic resin plate r. The metal substrate m subjected to the sandblast treatment could be bonded to the acrylic resin plate r, but resin foaming occurred at the bonding interface.

  Incidentally, Sample No. An AFM image of the surface to be processed before plasma processing equivalent to C2 is shown in FIG. FIG. 8B shows AFM images of the surface to be processed before plasma processing equivalent to C3. In either case, it can be seen that no particulate oxide is generated on the surface to be treated by thermal oxidation. From the above, it was found that it is effective to form the granular protrusions according to the present invention at the bonding interface in order to strongly laser-bond the metal material and the resin material without using an adhesive or the like.

《Wettability》
(1) Observation and measurement The water contact angle on the surface was measured to evaluate the wettability of each metal material. The results are shown in FIGS. FIG. 2 shows the wettability of the plasma-treated surface with respect to 2; FIG. 9B shows wettability when a silane coupling agent (coating material) is applied to the plasma treated surface. FIG. 4 shows the wettability of the surface to be processed before the plasma treatment. FIG. 9D shows wettability when a silane coupling agent is applied to the surface to be treated before the plasma treatment. FIG. The wettability of the to-be-processed surface before the plasma processing regarding C2 is shown.

  The silane coupling agent used here was decyltrichlorosilane, and its surface energy was 25 mN / m or less as measured by a wettability evaluation tester.

(2) Evaluation As is clear when FIG. 9A is compared with FIG. 9C and FIG. 9E, the water contact angle is greatly improved when the granular protrusions are present on the surface. In other words, it has been found that the water repellency on the surface can be greatly improved by creating granular protrusions on the surface of the metal material.

  9B and 9D, the water contact angle is about 80 ° even when a silane coupling agent is applied to a simple mirror surface (buffed surface), but the surface with granular protrusions has a silane cup. It was also found that when the ring agent was applied, the water contact angle was about 90, and the water contact angle was greatly improved. In addition, it is thought that the improvement in water repellency due to such granular protrusions depends on the Cassie mode.

Claims (12)

A method for producing a metal member comprising a metal material containing a specific transition metal element capable of generating a stable oxide and a metastable oxide having different oxidation numbers ,
An oxygen introduction step of introducing an oxygen active species into the surface of the metal material not covered with the stable oxide and having a fatty acid or fatty acid salt attached thereto ;
Method for producing a metal-based member granular protrusions consisting of oxides of the specific transition metal element raised from the surface is characterized by Rukoto formed. The method for producing a metal-based member according to claim 1 , wherein the oxygen active species is obtained by a plasma supply step of supplying plasma into an oxygen atmosphere. The method for producing a metal-based member according to claim 2 , wherein the oxygen atmosphere is an atmospheric pressure atmosphere. The method for producing a metal-based member according to any one of claims 1 to 3 , wherein the oxygen introduction step is performed on a surface of the metal material subjected to machining. Oxygen activity on a surface made of a metal material containing a specific transition metal element capable of generating stable oxides and metastable oxides having different oxidation numbers, and not coated with the stable oxides and having fatty acids or fatty acid salts attached thereto A step of joining a metal material having a granular protrusion made of an oxide of the specific transition metal element raised from the surface and a resin material, obtained by introducing a seed, through the granular protrusion. A method for producing a metal-based member . Said step of bonding, the laser light transmitted through the resin material by irradiating from the resin material side to the metallic material, comprising a heating step of heating at least near the surface of the metal member to be bonded to the resin material according Item 6. A method for producing a metal-based member according to Item 5 . The method for producing a metal-based member according to claim 5 or 6 , wherein the metal material has 25 or more / μm ² or more of the granular protrusions at a joint interface with the resin material. The said resin material is a manufacturing method of the metallic member in any one of Claims 5-7 containing oxygen (O) or nitrogen (N). Furthermore, the manufacturing method of the metallic member in any one of Claims 1-8 which has a coating | coated material which coat | covers the surface of the said metal material with the said granular protrusion, and reduces surface energy. The granular projections, method for producing a metal-based component according to any one of claims 1-9 height difference is 10 to 400 nm. The specific transition metal element is copper (Cu),
The method for producing a metal-based member according to claim 1, wherein the metastable oxide is copper (I) oxide (Cu ₂ O). The specific transition metal element is iron (Fe),
The method for producing a metal-based member according to any one of claims 1 to 11, wherein the metastable oxide includes iron (II) oxide (FeO).