JP4677050B1 - Film forming method and composite material formed by the method - Google Patents

Abstract

The present invention relates to a coating by a cold spray method, which makes it possible to form a coating having good adhesion strength, even if it is a combination of a substrate and particles for forming the coating, which has conventionally been difficult to form by a cold spray method. A forming method and a composite material obtained by the method.
A film forming method for forming a film on a surface of a substrate X by a cold spray method, the heating step for heating the surface of the substrate, and a roughening treatment with a working gas on the surface of the substrate after or simultaneously with the heating step. A pretreatment process for spraying the particles at supersonic speed to roughen the surface of the base material, and after the pretreatment process, the base material surface is coated with a working gas of 200 ° C. or higher and 900 ° C. or lower by a cold spray method. And a film forming step of spraying particles to form a film on the substrate surface.
[Selection] Figure 1

Description

  The present invention relates to a method for forming a film on a substrate surface by a cold spray method and a composite material including the film formed by the method.

  Today, composite materials in which a film is formed on the surface of a metal, ceramic, or organic base material and the function of the base film is added to the function of the base material have been put into practical use in various fields, and its applications are expanding. In order to form such a coating, various methods such as plating, sputtering, vapor deposition, and thermal spraying are used. Among them, the equipment is simple, and the coating is cold at low temperatures because the particles are sprayed at low temperature. The spray method is attracting attention.

  In such a cold spray method, construction is performed by appropriately changing conditions such as the type, temperature, and pressure of the working gas according to the combination of the base material and the particles to be sprayed. However, depending on the combination of the base material and the particles to be sprayed, it is often impossible to form a film having sufficient adhesion strength even if these working gas conditions are devised.

  Therefore, in order to improve the adhesion strength of the coating, for example, there is a method of forming a coating after spraying particles onto the surface of the substrate by shot blasting and then performing surface roughening (see Japanese Patent Application Laid-Open No. 2007-246967). Proposed. However, this method has a disadvantage in that a hard substrate such as ceramic cannot be sufficiently roughened. Also, although a method of performing thermal spraying while heating the material substrate from behind with a heater (see Japanese Patent Application Laid-Open No. 2008-302317) has been proposed, sufficient adhesion strength has not yet been obtained.

JP 2007-246967 A JP 2008-302317 A

  The present invention has been made in view of these disadvantages, and it is difficult to form a film by a conventional cold spray method, and a film having good adhesion strength even in a combination of a base material and particles for film formation. An object of the present invention is to provide a film forming method capable of forming a film.

The invention made to solve the above problems is
A film forming method for forming a film on a substrate surface by a cold spray method,
A heating step for heating the substrate surface;
After or simultaneously with the heating step, a pretreatment step in which the roughening treatment particles are sprayed onto the surface of the base material together with the working gas at a supersonic speed to roughen the surface of the base material;
After the pretreatment step, sprayed a film-forming granules with by Ri work dynamic gas in the cold spray method on the surface of the substrate, and a film formation step of forming a film on the substrate surface,
The base material is ceramic, the film-forming granules are metal granules,
The working gas temperature in the film forming step is 400 ° C. or higher and 900 ° C. or lower, the flow rate is 8 L / (min · mm ² ) or higher and 30 L / (min · mm ² ) or lower, and the pressure is 0.4 MPa or higher and 1 MPa or lower. Features.

  In this way, after the heating step of heating the substrate surface or simultaneously with this heating step, the working gas and the roughening treatment particles are sprayed onto the substrate surface at supersonic speed to perform the roughening treatment of the substrate surface. Thus, sufficient roughening treatment can be performed on the surface of the base material, which has been difficult to roughen. The base material and the coating film that have been difficult to form conventionally by forming the film by the cold spray method with the working gas temperature set to 400 ° C. or more and 900 ° C. or less on the roughened base material surface in this way. Even with the combination of forming granules, it is possible to form a film having good adhesion strength.

  The heating step may be performed by spraying a high temperature working gas in the pretreatment step or by spraying a roughening granule with a high temperature working gas in the pretreatment step. By heating the base material surface with the heat of the high temperature working gas or the heat of the high temperature working gas and the roughening treatment granules, the temperature of the base material can be more easily increased.

  The heating step may be performed by direct heating using a heating device. By directly heating the substrate, the temperature of the substrate can be increased more efficiently.

  In the film forming method, the temperature of the working gas in the pretreatment step is preferably 500 ° C. or higher and 900 ° C. or lower. By spraying particles for surface roughening treatment on the surface of the substrate together with working gas in this temperature range, surface roughening treatment can be applied to harder substrates, and film formation with high adhesion strength is possible It becomes.

  In the film forming method, ceramic is used as the substrate, and metal particles are used as the film forming particles. According to the film forming method, a metal film having good adhesion strength can be formed on the ceramic substrate.

In the film forming method, the temperature of the working gas in the film forming step is 400 ° C. or more and 900 ° C. or less, the flow rate is 8 L / (min · mm ² ) or more and 30 L / (min · mm ² ) or less, and the pressure is 0.4 MPa. The above is 1 MPa or less. More preferably, the temperature of the working gas is 450 ° C. or more and 550 ° C. or less, the flow rate is 10 L / (min · mm ² ) or more and 20 L / (min · mm ² ) or less, and the pressure is 0.5 MPa or more and 0.7 MPa or less. By forming a film by a cold spray method using a working gas having such temperature, flow rate, and pressure, a metal film having higher adhesion strength can be formed on the surface of the ceramic substrate.

  In the pretreatment step, metal particles may be sprayed together with the roughening treatment particles to form a bond layer on the substrate surface. By forming a bond layer on the surface of the substrate in this way and forming a film thereon by a cold spray method, the combination of the substrate and the particles for forming the film can be achieved only by roughening the surface of the substrate. Even when it is difficult to form a film, it is possible to form a film with good adhesion strength.

  In the film forming method, the pretreatment process and the film forming process may be performed using the same spraying means. By carrying out like this, a series of operation | work from the roughening process of a surface to film formation can be performed simply. In addition, since the film formation process can be performed without interruption after the pretreatment process, preheating for the film formation process can be efficiently performed in the pretreatment process, and a film with higher adhesion strength can be formed. Can do.

  Therefore, a composite material including a base material and a film formed on the surface of the base material by the film forming method has high adhesion strength.

  Here, “forming a film on the substrate surface” includes not only forming a film directly on the substrate surface but also forming a film via another layer. “Roughening particles” refers to particles that are sprayed onto the surface of the substrate in the pretreatment step to roughen the surface of the substrate, and in the pretreatment step of forming the bond layer, together with metal particles It refers to granules that adhere to the surface of a substrate to form a bond layer. “Supersonic speed” means a speed of 350 m / s or more. The “bond layer” is an intermediate layer sandwiched between a base material and a film, and is a layer serving as a base for forming the film.

  As described above, according to the method for forming a film of the present invention, it is possible to form a film having good adhesion strength even with a combination of a base material and particles for film formation, which is difficult to form a conventional film. It becomes possible to do.

1 is a system schematic diagram of a cold spray device used in a film forming method according to a first embodiment and a second embodiment of the present invention. It is a cross-sectional schematic diagram of the composite material provided with the bond layer and metal film which are obtained by the film formation method which concerns on 2nd Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings as appropriate. The film forming method includes a heating step for heating the substrate surface, and after or simultaneously with the heating step, the roughening treatment particles are sprayed on the surface of the substrate together with the working gas at a supersonic speed. And a film forming process for forming a film on the surface of the base material by spraying particles for forming the film together with a working gas of 200 ° C. or higher and 900 ° C. or lower on the surface of the base material by a cold spray method. And have.

  This film forming method can be suitably carried out using a cold spray apparatus as shown in FIG. By using this cold spray apparatus, the heating process, the pretreatment process, and the film forming process can be performed with the same configuration.

  The cold spray device of FIG. 1 includes a heater 1 that heats a working gas, a spray gun 2 that ejects particles at a supersonic speed together with the heated working gas, and a first particle that supplies various particles ejected from the spray gun 2. A body feeder 3 and a second grain feeder 4, a gas hose 7 for supplying a working gas to the heater 1, powder hoses 5 and 6 for feeding granules from the grain feeders 3 and 4 to the spray gun, and a grain feeder 3 4, gas lines 8 and 9 for supplying the working gas, a gas hose 7, a main gas line 10 for supplying the working gas to the gas lines 8 and 9, and a pressure gas supply device 11 for supplying the working gas to the main gas line 10. A control computer 12 for controlling the flow rate and temperature of the working gas, and the transfer of particles, and a spray booth 13 for performing work using the spray gun 2 It is provided. X is a base material which forms a film. In the two embodiments described below, the heating, pretreatment, and film formation steps described above are all performed by ejecting supersonic particles together with the working gas heated from the spray gun 2 by this configuration.

  Next, a mechanism for ejecting particles together with the working gas from the spray gun 2 will be described in detail. The granular feeders 3 and 4 are preliminarily provided with various types of surface roughening treatment granules and coating formation granules according to the type of the base material and the coating film, and metal grains when forming a bond layer described later. The body is filled. The working gas is heated by a heater 1 built in the spray gun 2. This working gas is supplied from the pressure gas supply device 11 to the heater 1 through the main gas line 10 and the gas hose 7. On the other hand, the working gas is also supplied from the pressure gas supply device 11 to the granule feeders 3 and 4 through the main gas line 10 and the gas lines 8 and 9. Granules are supplied to the spray gun 2 through the powder hoses 5 and 6 by this working gas. The granular material supplied to the spray gun 2 is heated by joining the working gas inside the spray gun 2 and accelerated at supersonic speed, and is sprayed from the spray gun 2 together with the working gas. The spray gun 2 has a narrowed portion for accelerating the working gas at supersonic speed inside, but the particles supplied from the powder hoses 5 and 6 to the spray gun 2 are either before or after the narrowed portion of the nozzle. It may be supplied. (FIG. 1 illustrates the case where the particles are supplied after the narrowed portion of the nozzle.)

  In addition, this cold spray device controls the transfer of particles from each of the particle feeders 3 and 4 to the spray gun 2 and the ejection of the particles by the spray gun 2, and further controls the flow rate and temperature of the working gas. The computer 12 for control is provided. The control computer 12 controls the ejection of the particles from the spray gun 2. The spray gun 2 travels in a direction perpendicular to the substrate surface while spraying particles on the substrate surface. A robot (not shown) is attached to the spray gun 2, and the traveling of the spray gun 2 is controlled by this robot.

<First Embodiment>
First, the film forming method according to the first embodiment of the present invention will be described. The film forming method according to the first embodiment includes a heating process for heating the substrate surface, a pretreatment process for roughening the substrate surface simultaneously with the heating process, and a film forming process for forming a film on the substrate surface. It consists of. In the first embodiment, since the heating process and the pretreatment process are performed simultaneously, this is the first process, and the film forming process is the second process.

(First step)
The first step includes a heating step for heating the substrate and a pretreatment step for spraying the roughening particles together with the working gas onto the surface of the substrate at a supersonic speed to roughen the surface of the substrate. It is a process to be performed. This will be specifically described below.

  In the cold spray apparatus shown in FIG. 1, the first granular feeder 3 is filled with a roughening treatment granule (hereinafter also referred to as “granule A”). Next, the working gas is heated by the heater 1, and is accelerated from the spray gun 2 by being accelerated at supersonic speed together with the particles A by the above-described procedure. When the high-temperature working gas injected from the spray gun 2 at supersonic speed and the heated granule A accelerated and supersonic by the working gas collide with the surface of the base material X to heat the surface of the base material X At the same time, roughening is performed.

(Substrate X)
The material used as the substrate X is not particularly limited, and examples thereof include metals, glass, ceramics, etc., and metals such as stainless steel, iron, copper, and aluminum, and ceramics such as alumina, aluminum nitride, silicon nitride, silicon carbide, and zirconia. Of these, aluminum, aluminum nitride, and alumina are particularly preferable. Moreover, the plate thickness in the case of using ceramic as the substrate X is not particularly limited, but is preferably 0.7 mm or more, and particularly preferably 0.9 mm or more. The upper limit of the plate thickness can be determined according to the application.

(Grain A for surface roughening treatment)
Although it does not specifically limit as a material of the granule A used for the roughening process of the base-material surface, For example, a metal, glass, a ceramic, etc. are mentioned, Hard metals, such as chromium, Alumina, silicon carbide, zirconia, etc. Ceramic is preferable, and alumina is particularly preferable among them.

  The average particle size of the granules A is not particularly limited, but is preferably 45 μm or more and 200 μm or less, and particularly preferably 60 μm or more and 100 μm or less. If the average particle size of the granules A exceeds 200 μm, the surface of the substrate may be too rough. On the other hand, if the average particle size exceeds 100 μm, the substrate may crack when the substrate is a ceramic thin plate. Further, if the average particle size of the granules A is less than 45 μm, the surface of the substrate may not be sufficiently roughened.

  The supply amount of the granule A is not particularly limited, but is preferably 20 g / min or more and 50 g / min or less, and particularly preferably 30 g / min or more and 40 g / min or less from the viewpoint of forming a film having higher adhesion strength.

  The flying speed of the granules A in the first step is not particularly limited, but is preferably 350 m / s or more and 450 m / s or less from the viewpoint of sufficiently performing the surface roughening treatment.

(Working gas)
The working gas temperature is not particularly limited, but is preferably 500 ° C. or higher and 900 ° C. or lower. If the working gas temperature is less than 500 ° C., the surface roughening treatment may be insufficient. In addition, it is not preferable to set the working gas to a temperature exceeding 900 ° C., because the base material X is oxidized or burned. However, depending on the material of the substrate X, the material of the granules A, the average particle diameter, or the shape, it can be suitably employed even at a temperature outside this range.

The working gas flow rate is not particularly limited, but is preferably 8 L / (min · mm ² ) or more and 30 L / (min · mm ² ) or less from the viewpoint of sufficiently performing the surface roughening treatment. In the case of subjecting a thin ceramic substrate to surface roughening treatment, 10 L / (min · mm ² ) or more is preferable from the viewpoint of sufficiently performing surface roughening treatment, and from the viewpoint of preventing the substrate from cracking, 20 L / ( Min · mm ² ) or less is preferable.

  The working gas pressure is not particularly limited, but from the viewpoint of sufficiently performing the surface roughening treatment, it is preferably 0.4 MPa or more and 1 MPa or less. When the thin ceramic substrate is subjected to the surface roughening treatment, the surface roughening treatment is sufficiently performed. From the viewpoint, 0.5 MPa or more is preferable, and from the viewpoint of preventing the base material from cracking, 0.7 MPa or less is preferable.

  The gas used as the working gas for heating the substrate and roughening the surface is not particularly limited. For example, air, nitrogen, helium, or a mixed gas thereof can be used, and air is excellent in economic efficiency and operability. Is particularly preferred.

(Distance between spray gun and substrate)
The distance between the spray gun and the substrate is not particularly limited, but is preferably 7 mm or more and 20 mm or less, and particularly preferably 10 mm or more and 15 mm or less from the viewpoint of forming a film having higher adhesion strength.

(Spray gun speed)
The moving speed of the spray gun in the first step is not particularly limited, but from the viewpoint of appropriately roughening the surface of the substrate in order to form a film having sufficient adhesion strength, it is 1 mm / s or more and 100 mm / s. The following are preferable, and 20 mm / s or more and 40 mm / s or less are preferable.

(Second step)
The second process is a film forming process in which, after the first process, the film forming granules B are sprayed onto the surface of the base material together with the working gas by a cold spray method to form a film on the surface of the base material. This will be specifically described below.

  In the cold spray apparatus shown in FIG. 1, the second particle feeder 4 is filled with particles for forming a film (hereinafter also referred to as “particles B”). The working gas is heated by the heater 1 according to the above-described procedure, and is accelerated at supersonic speed together with the granular material B and sprayed from the spray gun 2. The high-temperature working gas injected from the spray gun 2 at supersonic speed and the heated granule B accelerated to supersonic speed by this working gas collide with the surface of the base material X after the surface roughening treatment. . In this way, the granule B adheres to the surface of the substrate X and is laminated, and a film is formed on the surface of the substrate X.

The first step and the second step may be performed using the same injection means, that is, the spray gun 2.
Specifically, the granular material B is filled in the second granular material feeder 4 before the first step. By carrying out like this, since a 2nd process can be performed continuously after a 1st process, a 2nd process can be performed in the state by which the base material X became suitable temperature by the 1st process, and a 2nd process When the substrate X needs to be preheated, the substrate X can be efficiently preheated.

(Granule B for Film Formation)
The material of the film forming granule B is not particularly limited, and examples thereof include various metals and various ceramics. Examples of the metal include copper, aluminum, titanium, gold, silver, nickel, zinc, iron, tantalum, and niobium. Pure metals such as nickel chrome alloys, nickel-base superalloys, stainless steels, zinc alloys, aluminum alloys, copper alloys and the like. When forming a composite of a ceramic substrate and a conductive material, copper, aluminum, gold, silver, nickel, zinc or an alloy of two or more of these is preferable, and copper, silver, aluminum and an alloy of these are Particularly preferred.
Further, as the ceramic particles, agglomerated particles are preferable, and agglomerated titanium oxide is particularly preferable.

  The average particle diameter of the film forming granules B is not particularly limited, but from the viewpoint of suppressing the aggregation phenomenon of the film forming granules B and stabilizing the supply of the granules B from the particle feeder to the spray gun 2, The average particle diameter of the granule B is preferably 5 μm or more, particularly preferably 10 μm or more. Further, from the viewpoint of suppressing the surface of the base material from being scraped by the impact of the collision of the granules B with the base material surface, 100 μm or less is preferable, and 65 μm or less is particularly preferable. When the grain B is a ceramic aggregated titanium oxide, the average grain size of the aggregated grain is preferably 5 μm or more and 30 μm or less.

  The supply amount of the granules B is not particularly limited, but is preferably 5 g / min or more and 9 g / min or less, and particularly preferably 6 g / min or more and 8 g / min or less.

  The flying speed of the granules B in the working gas in the second step is not particularly limited, but is preferably 400 m / s or more and 500 m / s or less when the base material is ceramic and the granules B are metal.

(Working gas)
It is important that the working gas temperature is 200 ° C. or higher and 900 ° C. or lower. By setting the working gas temperature to a temperature in this range, the effect of the present invention that a film having good adhesion strength can be formed can be obtained. When the substrate is ceramic and the particle B is a metal, the temperature is preferably 400 ° C. or more and 900 ° C. or less, and when the particle B is copper, the temperature is particularly preferably 450 ° C. or more and 550 ° C. or less. If the temperature of the working gas is less than 450 ° C., the adhesion strength may decrease in the case of a copper coating. If the working gas temperature exceeds 550 ° C, the copper coating may be oxidized. In particular, when the working gas temperature exceeds 600 ° C., the copper film is oxidized and colored, so that the temperature is preferably 600 ° C. or less. However, depending on the material of the base material, the material of the granule B, the average particle diameter or the shape, it can be suitably employed even at a temperature outside this range.

The working gas flow rate is not particularly limited, but is preferably 8 L / (min · mm ² ) or more and 30 L / (min · mm ² ) or less when the base material is ceramic and the film forming particles are metal, 10 L / (min · mm ² ) or more and 20 L / (min · mm ² ) or less is particularly preferable.

  The working gas pressure is not particularly limited, but is preferably 0.4 MPa or more and 1 MPa or less, and particularly preferably 0.5 MPa or more and 0.7 MPa or less when the base material is ceramic and the granule B is metal.

  The gas used as the working gas is not particularly limited. For example, air, nitrogen, helium, or a mixed gas thereof can be used, and air is particularly preferable because it is excellent in economy and operability. However, from the viewpoint of suppressing the oxidation of the formed metal film, an inert gas such as nitrogen or helium is preferable. From the viewpoint of ejecting particles from the spray gun 2 at a higher speed, helium, helium, and nitrogen are used. A mixed gas is preferred.

(Distance between spray gun and substrate)
The distance between the spray gun and the base material in the second step is not particularly limited, but the distance in the first step can be suitably used.

(Spray gun speed)
The movement speed of the spray gun in the second step is not particularly limited, but from the viewpoint of forming a film having sufficient adhesion strength, it is preferably 1 mm / s or more and 120 mm / s or less, and 40 mm / s or more and 80 mm / s or less. Particularly preferred.

(Coating)
Although the minimum of the thickness of the film formed at a 2nd process is not specifically limited, From a viewpoint of reducing the porosity, 5 micrometers or more are preferable and 10 micrometers or more are especially preferable.

  The adhesion strength of the coating is not particularly limited, but in the case of a metal coating formed on a ceramic substrate, 0.1 MPa or more is preferable, and 1.0 MPa or more is particularly preferable.

(Composite material)
Since the composite material formed by 1st Embodiment has favorable adhesive strength, it is used suitably as a material of an industrial product. Although the composite material formed by 1st Embodiment is not specifically limited, The thing which formed the film of copper, silver, gold | metal | money, or aluminum on the ceramic base material, Titanium oxide on the base material of aluminum, iron, stainless steel, or copper, Examples include those in which a coating of copper, silver, gold, aluminum, titanium, tantalum, niobium, inconel, nickel-based alloy or cobalt-based alloy is formed.

<Second Embodiment>
Next, a film forming method according to the second embodiment of the present invention will be described. The coating film forming method according to the second embodiment is also referred to as a metal particle (hereinafter referred to as “particle C”) together with a roughening treatment particle on the substrate surface simultaneously with a heating step for heating the substrate surface and the heating step. ) And a roughening process is performed on the surface of the base material, and a pretreatment process for forming a bond layer as shown in FIG. 2 and a film formation process for forming a film on the surface of the bond layer are included. Specifically, in the second embodiment, since the heating step and the pretreatment step are performed at the same time, this will be described as the first step, and the film forming step will be described as the second step.

  Here, the bond layer Y is an intermediate layer sandwiched between the substrate X and the coating Z in the composite material of FIG. 2 and is formed to further improve the adhesion of the coating to the substrate X. In the first step in the second embodiment, the surface roughening treatment granules A are heated and roughened on the surface of the base material, and are adhered to the surface of the base material X and laminated. That is, the bond layer Y is formed by laminating both the particles A and the metal particles C on the base material.

(First step)
The first step in the second embodiment is a heating step of heating the base material, and sprays particles A and particles C together with the working gas onto the surface of the base material at a supersonic speed to form a bond layer on the surface of the base material. This is a step of simultaneously performing the pretreatment step. This will be specifically described below.

  In the cold spray device of FIG. 1, the first granule feeder 3 is mixed and filled with the granule A and the granule C, and the second granule feeder 4 is filled with the granule B. The working gas is heated by the heater 1 according to the above-described procedure, and is accelerated together with the particles A and C at a supersonic speed and sprayed from the spray gun 2. The high-temperature working gas injected from the spray gun 2 at supersonic speed, and the heated granule A and granule C that are accelerated to supersonic speed by this working gas collide with the surface of the substrate X. In this way, the granules A and the granules C are adhered and stacked on the surface of the substrate X, and a bond layer is formed on the surface of the substrate X.

  The method of mixing the particles A and the particles C for forming the bond layer is not particularly limited, but may be mixed before filling the particle feeders 3 and 4 as described above, or the first particles The body feeder 3 is filled with one of the granules A and C, and the second grain feeder 4 is filled with other granules, and these are separately supplied to the spray gun 2. It is also possible to mix inside the spray gun 2. Thus, by supplying the granule A and the granule C separately to the spray gun 2, the granule can be mixed more easily.

(Substrate X)
As the substrate X used in the second embodiment, the substrate X exemplified in the first embodiment can be suitably used.

(Granule A)
Although it does not specifically limit as a material of the granule A which forms the bond layer of a 1st process, The granule A in 1st Embodiment can be used suitably. As the metal, chromium is preferable, and as the ceramic, alumina, silicon carbide, zirconia and the like are preferable, and alumina is particularly preferable from the viewpoint of sufficient surface roughening treatment, availability, and economical efficiency.

  Although the average particle diameter of the granule A is not specifically limited, 15 micrometers or more and 65 micrometers or less are preferable. If the average particle size is less than 15 μm, the surface of the substrate cannot be sufficiently roughened and a bond layer may not be formed. If the average particle size exceeds 65 μm, the substrate may be impacted by a collision with the substrate surface. There is a risk of scraping the surface or the newly formed bond layer. When the substrate is a ceramic thin plate, the average particle size of the granules A is preferably 15 μm or more and 50 μm or less. If the average particle size exceeds 50 μm, the ceramic substrate may be cracked.

(Metal Granule C)
Although it does not specifically limit as a material of the metal granule C used for a 1st process, The same metal as the metal particle used for the film formed in the surface of copper, aluminum, silver, nickel, or a bond layer is preferable.

  Although the average particle diameter of the granule C is not specifically limited, 10 micrometers or more and 65 micrometers or less are preferable, and 15 micrometers or more and 50 micrometers or less are especially preferable. If the particle size is less than 10 μm, there is a possibility that the particles C may agglomerate and it is difficult to supply from the particle feeder, and if the particle size exceeds 65 μm, the particle C is newly formed on the substrate surface due to the impact of the collision with the substrate surface. There is a risk of scraping the bonded layer.

  The total supply amount of the granule A and the granule C forming the bond layer is not particularly limited, and is preferably 6 g / min or more and 10 g / min or less, and particularly preferably 7 g / min or more and 9 g / min or less.

  The flying speed of the granules A and C in the working gas when forming the bond layer is not particularly limited, but is preferably 350 m / s or more and 400 m / s or less.

(Working gas)
The working gas temperature in the first step is not particularly limited, but is preferably 400 ° C. or higher and 550 ° C. or lower when the substrate X is ceramic. If it is lower than 400 ° C., it may be difficult to form a bond layer having sufficient adhesion strength with the ceramic. When the working gas temperature exceeds 550 ° C., oxidation of the metal forming the bond layer may become remarkable. When the granule C is copper, when the working gas temperature is 600 ° C. or higher, the bond layer film is oxidized and becomes a coffee color. However, temperatures outside this range can be suitably employed depending on the material of the substrate X, the material of the granules C, the average particle diameter, or the shape.

  The gas used as the working gas is not particularly limited. For example, air, nitrogen, helium, or a mixed gas thereof can be used, and air is particularly preferable because it is excellent in economy and operability. However, an inert gas such as nitrogen or helium is preferable from the viewpoint of suppressing oxidation of the metal in the formed bond layer, and helium and helium from the viewpoint of ejecting particles from the spray gun 2 at a higher speed. A mixed gas of nitrogen and nitrogen is preferred.

(Distance between spray gun and substrate)
The distance between the spray gun 2 and the substrate X is not particularly limited, and the distance between the spray gun and the substrate in the first step of the first embodiment can be suitably used.

(Spray gun speed)
The moving speed of the spray gun in the first step is not particularly limited, but is preferably 5 mm / s or more and 100 mm / s or less from the viewpoint of forming an appropriate bond layer for forming a film having sufficient adhesion strength. / S to 50 mm / s is particularly preferable.

  The volume ratio of the granules A to the entire volume of the bond layer Y is not particularly limited, but from the viewpoint of increasing the adhesion strength between the base X and the coating Z and preventing the granules A from flowing out after the coating is formed, 50 % Or less is preferable, and 30% or less is particularly preferable. Since the granule A is less likely to remain in the bond layer than the granule C, the entire granule to be ejected (the granule A and the granule C and the volume of the granule A to be ejected onto the substrate X) The ratio of the total volume) is preferably 40% or more and 50% or less.

(Second step)
In the second step of forming a film on the substrate X on which the bond layer has been formed in the first step, the working gas temperature is 200 ° C. or higher and 900 ° C. or lower. As other conditions, various conditions in the second step of the first embodiment can be suitably employed.

(Granule B)
It does not specifically limit as a material of the granule B used at a 2nd process, What was illustrated in the granule B used at the 2nd process of 1st Embodiment can be used. Among these, a metal particle can be used suitably and the same metal as the metal particle C used for bond layer formation is especially preferable.

  Moreover, as an average particle diameter of the granule B used at a 2nd process, the average particle diameter of the granule B in the 2nd process of 1st Embodiment can be used suitably.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The coatings obtained as examples and comparative examples were evaluated by performing the following tests according to the following procedures.

<Evaluation method>
(Tape peeling test)
The cellophane tape was applied to the surface of the coating formed on the substrate and peeled off, and it was visually confirmed whether or not the coating was peeled off. The case where there was no peeling was marked with “◯”, and the case where there was slight peeling was marked with “X”.

(Adhesion strength test)
A test piece was prepared by pasting a cross section of an iron round bar having a diameter of 25 mm on the coating surface having a diameter of 25 mm formed on the substrate with an epoxy adhesive. Using a bowl-shaped jig with an inner dimension of 65 mm x 65 mm x 70 mm with a through hole with a diameter of 28 mm in the center of the bottom, with the round bar portion of the test piece facing downward, the through hole in the jig bottom from the inside of this jig The test piece was set so that the surface on the round bar side of the base material was in contact with the inner surface of the bottom of the jig. Using a tensile tester (Instron "5583 type"), the strength at which the coating peeled off was measured by pulling the round bar adhered to the coating surface downward through this jig, and this strength was defined as the adhesion strength. .
(Visual test)
The formed bond layer and film were visually observed to examine the degree of oxidation. “X” indicates a coffee color, “Δ” indicates a discoloration that is not coffee color, but “◯” indicates no discoloration.

<Film formation 1>
In order to investigate the relationship between the working gas temperature during the surface roughening treatment and the adhesion strength of the coating, and the relationship between the average particle size of the particles for surface roughening treatment and the adhesion strength of the coating, the method described in the first embodiment is used. According to the above, a film was formed, and composite materials of Examples 1 to 9 and Comparative Examples 1 to 3 were obtained and evaluated by performing a tape peeling test and an adhesion strength test.

Example 1
Masking having a circular opening was performed on the substrate to form a circular metal film having a diameter of 25 mm under the following conditions. The temperature of the working gas is measured by a thermocouple installed at the spray gun outlet.
[Conditions for implementation]
・ Base material: Aluminum (A5051)
・ Base material dimensions: 50mm x 50mm x 5mm
<Surface roughening conditions>
-Surface roughening particles: Alumina (particle size; # 220)
-Working gas: Air-Working gas temperature: 580 ° C
・ Working gas flow rate: 16.7 L / (min · mm ² )
-Working gas pressure: 0.63 MPa
・ Spray gun speed: 30mm / s
・ Distance between spray gun and substrate: 10mm
・ Granule supply rate: 35 g / min <film formation conditions>
-Particles for film formation: copper powder (average particle size: 40 μm)
-Working gas: Air-Working gas temperature: 550 ° C
・ Working gas flow rate: 16.7 L / (min · mm ² )
-Working gas pressure: 0.60 MPa
・ Spray gun speed: 60mm / s
・ Distance between spray gun and substrate: 10mm
・ Granule supply: 7 g / min

(Examples 2-9 and Comparative Examples 1-3)
Example 1 except that the material of the substrate, the method used for the surface roughening treatment, the working gas temperature during the surface roughening treatment, and the particle size of the alumina for surface roughening treatment were as described in Table 1 and Table 2. In the same manner, a metal film was formed on the base material to obtain composite materials of Examples 2 to 9 and Comparative Examples 1 to 3, and evaluated by performing the above test. However, the gas pressure when the surface roughening treatment is performed by shot blasting is 0.6 MPa. The alumina substrate used was 50 mm × 50 mm × 1.2 mm. Tables 1 and 2 show the execution conditions and the evaluation results of the coatings obtained.

  As is clear from the results of Tables 1 and 2, it can be seen that the coatings obtained in Examples 1 to 9 all have good adhesion strength. When surface roughening treatment is performed using a spray gun of a cold spray device, the surface roughening treatment is performed at a higher temperature than the case where the surface roughening treatment is performed at room temperature. It was found that the strength increased. Further, as is apparent from the results in Table 2, in the case of a thin ceramic substrate, if the surface roughening treatment is performed with a coarse particle for surface roughening treatment using shot blasting, the substrate is cracked. I understood that.

<Film formation 2>
(Examples 10 to 15)
In order to investigate the relationship between the working gas temperature during film formation and the adhesion strength of the film, a film was formed in the same manner as in Example 8 except that the working conditions shown in Table 3 were used. A tape peeling test, an adhesion strength test, and a visual test of the coating were evaluated. The execution conditions and the evaluation results of the obtained coating film are shown in Table 3.

  As is apparent from the results in Table 3, when a metal film is formed on the ceramic substrate, a higher adhesion strength can be obtained by setting the working gas temperature at the time of film formation to 400 ° C or higher, more preferably 450 ° C or higher. I found out that Moreover, in the case of a copper film, when it exceeded 550 degreeC, oxidation became remarkable, and when it exceeded 600 degreeC, it turned out that the color changes a lot.

<Film formation 3>
(Examples 16 to 19)
In order to investigate the relationship between the working gas pressure during film formation, the working gas flow rate during film formation, and the adhesion strength of the film, a film was formed in the same manner as in Example 8 except that the working conditions shown in Table 4 were used. The composite materials of Examples 16 to 19 were obtained and evaluated by performing a tape peeling test and an adhesion strength test. The evaluation results are shown in Table 4.

As is apparent from the results in Table 4, when a metal film is formed on the ceramic substrate, the working gas pressure during film formation is 0.4 MPa or more, and the gas flow rate at the spray gun outlet is 8 L / (min · mm ² ) or more. It was found that a film having good adhesion strength can be formed. Moreover, when forming a metal film on a ceramic base material, it turned out that higher adhesion strength is obtained by making the working gas pressure at the time of film formation into 0.5 MPa or more. Furthermore, in the case of a thin ceramic substrate, the substrate does not crack by setting the working gas pressure at the time of coating formation to 0.7 MPa or less and the gas flow rate at the spray gun outlet to 20 L / (min · mm ² ) or less. I understood that I could do it.

<Film formation 4>
In the case of forming a film after first forming a bond layer on the substrate, a metal film is formed under the following conditions in order to investigate the relationship between the working gas temperature at the time of bond layer formation and the adhesion strength of the film And the composite material of Examples 20-24 was obtained, and the tape peeling test, the adhesive strength test, and the visual test of the bond layer were implemented and evaluated.

(Example 20)
According to the method shown in the second embodiment, the test was performed under the following conditions. The center part of the base material on which the metal film was formed was left in a circular shape with a diameter of 25 mm, and the other part was masked to form a bond layer and a metal film.
[Conditions for implementation]
-Base material: Alumina-Base material dimensions: 50mm x 50mm x 1.2mm
<Bond layer formation conditions>
-Surface roughening particles: Alumina (particle size; # 220)
Metal particles: copper powder (average particle size: 40 μm)
-Working gas: Air-Working gas temperature: 400 ° C
・ Working gas flow rate: 16.7 L / (min · mm ² )
-Working gas pressure: 0.60 MPa
・ Spray gun speed: 60mm / s
・ Distance between spray gun and substrate: 10mm
・ Granule supply rate: 8 g / min <film formation conditions>
-Particles for film formation: copper powder (average particle size; 40 μm)
・ Working gas: Air ・ Working gas temperature: 500 ℃
・ Working gas flow rate: 16.7 L / (min · mm ² )
-Working gas pressure: 0.60 MPa
・ Spray gun speed: 60mm / s
・ Distance between spray gun and substrate: 10mm
・ Granule supply: 7 g / min

(Example 21 to Example 24)
A metal film was formed in the same manner as in Example 20 except that the working gas temperature during bond layer formation was as described in Table 5. The results are shown in Table 5.

  As is apparent from the results in Table 5, when a metal film is formed after forming a bond layer on a ceramic substrate, a high adhesion strength is obtained when the working gas temperature is 400 ° C. or higher and 550 ° C. or lower when forming the bond layer. It turns out that it is obtained. Moreover, when the working gas temperature at the time of bond layer formation is set to 550 ° C. or lower, oxidation of the metal film forming the bond layer can be suppressed, and when it is set to 600 ° C. or lower, copper can be suppressed from becoming a coffee color. It was.

  The film forming method of the present invention is not limited to the first and second embodiments. For example, by performing the pretreatment step after the heating step, the substrate can be brought into a high temperature state from the start of the pretreatment step, and the roughening treatment of the substrate surface can be performed efficiently. Moreover, a heating process can also be performed by heating a base material directly with heating apparatuses, such as an infrared heater and an electric heater. It is also possible to perform the surface roughening treatment in the pretreatment step using an apparatus such as shot blasting. Moreover, the surface roughening process of a pre-processing process can also be performed, heating with a laser apparatus. Moreover, the surface roughening process of a heating process and a pre-processing process can also be performed with a laser apparatus.

  According to the film forming method of the present invention, since the surface roughening treatment can be performed even on the base material, which has been difficult in the past, as described above, composite materials in various fields are manufactured by the cold spray method. In this case, it can be suitably used.

1 Heater 2 Spray gun
3 First Granule Feeder 4 Second Granule Feeder 5 Powder Hose 6 Powder Hose
7 Gas hose
8 Gas line
9 Gas line 10 Main gas line 11 Pressure gas supply device 12 Computer for control 13 Spray booth X Base material Y Bond layer Z Coating

Claims (8)

A film forming method for forming a film on a substrate surface by a cold spray method,
A heating step for heating the substrate surface;
After or simultaneously with the heating step, a pretreatment step in which the roughening treatment particles are sprayed onto the surface of the base material together with the working gas at a supersonic speed to roughen the surface of the base material;
After the pretreatment step, sprayed a film-forming granules with by Ri work dynamic gas in the cold spray method to the substrate surface, and a film formation step of forming a film on the substrate surface possess,
The base material is ceramic, the film-forming granules are metal granules,
The working gas temperature in the film forming step is 400 ° C. or higher and 900 ° C. or lower, the flow rate is 8 L / (min · mm ² ) or higher and 30 L / (min · mm ² ) or lower, and the pressure is 0.4 MPa or higher and 1 MPa or lower. A method for forming a film.   The film forming method according to claim 1, wherein the heating step is performed by spraying a high-temperature working gas in the pretreatment step or by spraying a roughening granule with a high-temperature working gas in the pretreatment step. The heating step, the film forming method of the serial placement in claim 1 carried out by direct heating using a heating device.   The film forming method according to claim 1, 2, or 3, wherein the temperature of the working gas in the pretreatment step is 500 ° C or higher and 900 ° C or lower. The temperature of the working gas in the film forming step is 450 ° C. or more and 550 ° C. or less, the flow rate is 10 L / (min · mm ² ) or more and 20 L / (min · mm ² ) or less, and the pressure is 0.5 MPa or more and 0.7 MPa or less. The method for forming a film according to claim 1 . In the said pre-processing process, a metal particle is sprayed with the grain for roughening process, and the bond layer which is an intermediate | middle layer pinched | interposed into a base material and a film is formed in the base material surface . 2. The method for forming a film according to item 1. The film forming method according to any one of claims 1 to 6 , wherein the pretreatment step and the film forming step are performed using the same spraying means. A substrate;
A composite material comprising: a coating film formed on the substrate surface by the coating film forming method according to any one of claims 1 to 7 .

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