JP4892722B2 - Coating apparatus and processing method thereof - Google Patents

Description

  The present invention uses ultrasonic energy such as ultrasonic waves to form a metal, metal compound, or ceramic coating film on the surface of a metal material having various shapes in a short processing time, or a metal or ceramic composite film. The present invention relates to a coating apparatus and a processing method therefor.

  Conventionally, as a coating method of a metal material, there are electroplating, spray coating, vapor deposition, and the like, but there are limits to the types of materials that can be applied. The main factor is the compatibility between the substrate material and the coating material. For example, it is extremely difficult to coat a material mainly composed of a high melting point substance on the surface of a low melting point metal substrate. In the conventional method, there are many restrictions on conditions such as gas atmosphere and temperature at the time of coating, and relatively expensive equipment such as laser irradiation, arc generation, and high vacuum is required.

  Conventionally, a mechanical coating method for imparting a new function to a metal material surface has been reported (for example, see Patent Document 1). This is because at least vibration occurs in a space between a transducer that generates ultrasonic waves, a vibrator that transmits the vibration of the transducer to the diaphragm, a diaphragm attached to the vibrator, and a processing surface that faces the diaphragm. By using an ultrasonic shot peening machine consisting of a holder for sealing, including the outer periphery of the plate, and shot grains that move within the sealed space and impact the processing target, it is used for alloy formation at the processing target In this case, an alloy surface layer having a composition different from that of the metal material (base material) to be processed is formed. However, Patent Document 1 is based on the premise that the vibrator is disposed above the surface of the metal material, and is directed to coating the upper surface of the metal material. Therefore, the concept of efficiently converting ultrasonic vibration energy into shot kinetic energy by resonating the cover (chamber) is lacking. In other words, there is no mechanism that gives kinetic energy to the ball existing on the surface of the metal material, so that once the energy is lost, the ball does not participate in the coating, and may interfere with the collision between another ball and the material surface. large.

  In addition, after the stainless steel ball, metal powder, and the object are stored in the stainless steel pot, the stainless steel pot is rotated on the ball mill base and mechanical alloying treatment is performed to diffuse the metal powder on the surface of the object. There has been proposed a metal powder coating method by a mechanical alloying method, characterized in that a metal powder coating layer is formed on the surface of an object by heat treatment (see, for example, Patent Document 2). However, in Patent Document 2, there is a limitation that it is difficult to increase the collision speed because the object and the ball move in a macro manner, and the object is limited to a size within the pot.

JP 2004-169100 A JP-A-5-345901

  An object of the present invention is to use ultrasonic energy such as ultrasonic waves to form a coating film of metal, a metal compound, or a ceramic on a surface of a metal material having various shapes in a short processing time. An object of the present invention is to provide a coating apparatus and a processing method for forming a composite film.

According to the present invention, an oscillator having an automatic frequency adjustment function, a transducer for generating ultrasonic waves, a vibrator for transmitting the vibration of the transducer, a cylindrical resonance chamber, and a lid for the resonance chamber and be coated metallic material disposed or resonance chamber is arranged Jo, consists, a ball made of metal or ceramics in the resonance chamber, the powder of metal or ceramics is charged, at least the A resonance chamber is vibrated by applying a high-frequency sound wave or an ultrasonic wave adjusted to a resonance frequency f under load in a state where the ball and the powder are loaded, and the ball and the powder are the metal material to be coated. are adapted to the coating is carried out by impinging on, the resonance frequency f when the load Coating apparatus which is a frequency calculated based on at least the ball and approximation formula powder and representing the relationship between the resonance frequency f ₀ at the time of no load in a state of not being charged (1) .
Here, M _C is the weight of the resonance chamber, M _B is the total weight of the ball and the powder was placed in a resonance chamber, G _S is overall rigidity of the oscillator (N / m).

In addition, according to the present invention, there is obtained a coating apparatus in which the height h dimension of the resonance chamber satisfies the following formula (2).
Here, C is the speed of sound (m / s) in the material constituting the resonance chamber.

In addition, according to the present invention, a metal or ceramic ball and metal or ceramic powder are placed in the resonance chamber, and the target metal material precoated by coating the entire surface of the metal or ceramic powder or by patterning, By placing the resonance chamber or the resonance chamber so as to face the surface, by applying a high-frequency sound wave or an ultrasonic wave adjusted to the resonance frequency f at the time of loading in a state where at least the ball and the powder are loaded. Coating is performed by applying vibration to a resonance chamber and causing the ball and the powder to collide with the metal material to be coated. The resonance frequency f under load is at least the ball and the powder. body and is at no load in a state that has not been charged Coating treatment method which is a frequency calculated based on the approximate expression (1) representing the relationship between the frequency f ₀ tinnitus.
Here, M _C is the weight of the resonance chamber, M _B is the total weight of the ball and the powder was placed in a resonance chamber, G _S is overall rigidity of the oscillator (N / m).

Further, according to the present invention, as the powder, according to claim 1, characterized in that the coating process using a mixed powder of magnetic powder or nonmagnetic powder and the magnetic powder, is performed A coating device is obtained.

Further, according to the present invention, as the powder, according to claim 3, characterized in that magnetic powder or coating process using a mixed powder of non-magnetic powder and the magnetic powder is carried out A coating method is obtained.

According to the present invention, the following effects can be obtained.
1) Dissimilar material coating at normal temperature and normal pressure 2) Short-time coating 3) Patterned coating 4) Object coating of various shapes 5) High adhesion between coating agent and material surface, Adhesion 6) Coating thickness 7) Addition of (compressive) residual stress to material surface, processing effect 8) Facilitation of nano / micro structure formation

In addition, the present invention has the following specific features.
1． Due to the violent collision between the ball and the inner wall of the resonance chamber, metal or ceramic powder is driven into the substrate surface, and the oxide film on the substrate and the powder surface is destroyed, facilitating diffusion bonding between the new surfaces. Therefore, it is possible to coat or compound a metal substrate that is easily oxidized, such as Al and Ti.
2. Due to the intense collision between the ball and the inner wall of the resonance chamber or between the balls, it is possible to momentarily apply a large stress to the powder, which causes the powder to be crushed and deformed, resulting in ultra-fine and non-crystallized powder. And activation by strain energy accumulation proceeds. Therefore, formation of an extremely strong coating layer or composite layer having a nano or micro structure, generation of intermetallic compounds, oxides, carbides, nitrides, and the like are promoted.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows a basic configuration of an apparatus for pattern coating on the surface of a plate-shaped metal material as an example of an apparatus used when the present invention is implemented. 100 stainless balls (1, 3 mm in diameter) and 0.5 g of titanium powder (2 in the figure) are put into a cylindrical titanium resonance chamber (3) with an inner diameter of 32 mm, a height of 56 mm, and a wall thickness of 1.5 mm. The chamber is fixed to the tip of the vibrating rod of the magnetostrictive ultrasonic transducer by a screwed joint. Attach a protective ring (4) made of porous soft material (foam rubber, etc.) to the top of the container. This ring is intended to prevent the balls from being discharged outside the container during operation and to allow gas supply from the outside. Place the aluminum flat plate (5) pre-coated with organic adhesive in a linear pattern on the protective ring and apply the load (6) from above as shown in Fig.2. The resonance chamber and the flat plate are placed in a box-shaped container filled with argon gas, or blown into the resonance chamber as shown in FIG. The transducer is irradiated with ultrasonic waves with an electrical input of 1kW and a frequency of 21750Hz for 10 minutes. This frequency coincides with one of the resonance frequencies of the resonance chamber. An enlarged photograph of the surface obtained after the coating treatment is shown in FIG. As described above, this apparatus can also be used for surface coating of a plate-like metal material to which a magnetic field is applied. In that case, for example, instead of the load (6), a permanent magnet is placed on the surface to be processed, or the load and the magnet are exchanged during the processing.

  In order to coat the surface of a material having a bulk shape such as a sphere, a rod, or a rectangular parallelepiped, the size of the resonance chamber is adjusted to the material shape as described above, and the upper end is formed as shown in FIGS. Close the lid, suspend the material to be coated (5) inside the resonance chamber with the connecting rod fixed to the lower end of the lid (6), adjust the frequency so that resonance vibration of the chamber occurs, and apply the coating treatment. Do

  A specimen is cut out from the metal material after coating, annealed under appropriate conditions, and then evaluated for surface hardness, wear resistance, and corrosion resistance, as well as SEM observation and EPMA surface analysis of the surface layer thickness and coating layer components. It was measured by. The results are shown in Table 1 together with the processing conditions. As can be seen from Table 1, in the case where the aluminum plate was subjected to ultrasonic coating treatment using titanium powder for 15 minutes (Example 3, no surface pretreatment), the comparative example despite the film formation rate of 34% Compared to 1, a surface hardness of 3 times or more was obtained. This is a result attributed to the processing effect due to repeated collision of the stainless balls other than the formation of the titanium film.

  In the case where the aluminum plate surface was pre-coated with titanium powder suspended in ethyl acetate and treated for 10 minutes (Example 4), the film formation rate and the thickness were remarkably increased. As a result, the surface hardness was improved by 7.5 times, the wear resistance was improved by 40%, and the corrosion resistance was improved by 80 times.

  Moreover, patterning of the pre-coating on the aluminum plate surface with titanium powder (Example 5) was performed as follows. Place a plastic film with holes on the surface of the aluminum plate and apply grease. Thereafter, when the plastic film is taken, a pattern in which grease is applied in stripes remains on the surface of the aluminum plate. In this state, as in Example 3, ultrasonic coating with titanium powder is performed. As a result, as shown in FIG. 5, only about 70% of the surface was coated with the titanium powder in a stripe pattern. Again, the surface coated with titanium powder was 5.6 times as hard as the base metal.

  Example 6 is a case where an aluminum plate is used as a base material and a mixed powder of nickel and tungsten is subjected to ultrasonic coating while applying a magnetic field from above with a permanent magnet. The ball material in this case was zirconia. The coating process was performed for 2 minutes without applying a magnetic field in order to promote the formation of a composite of ferromagnetic nickel powder and tungsten, and then the coating process was continued for another 4 minutes while applying the magnetic field. As a result, a composite film of nickel and tungsten was formed on almost the entire surface of the aluminum plate. As a result, the hardness and wear properties were significantly improved.

  Example 7 is a case in which the steel surface was subjected to ultrasonic precoating for 20 minutes after patterning pre-coating with zirconia carbide powder in the same manner as in Example 5. As a result, a coating layer having an average thickness of 9 μm was formed, and in the coated portion, the hardness was increased by 9 times and the wear resistance was improved by 50%.

  Example 8 is a case in which a cubic steel material having a side of 2 cm is pre-coated with a mixed powder of nickel, chromium and aluminum in the same manner as in Example 4 and then subjected to ultrasonic coating treatment for 20 minutes. is there. The coating apparatus shown in FIG. 3 was used. A composite film of nickel, chromium, and aluminum with an average layer thickness of 15 μm was formed at a ratio of 90%, and the hardness and corrosion resistance were improved by 2.8 times and 27 times, respectively.

  Example 9 is a case where a cylindrical steel material having a diameter of 10 mm and a height of 30 mm was pre-coated with titanium carbide powder in the same manner as in Example 4 and then subjected to ultrasonic coating treatment for 10 minutes. . The coating apparatus shown in FIG. 4 was used. The coating thickness of titanium carbide averaged 7.4μm, and the hardness and corrosion resistance were improved by 4.4 times and 17 times, respectively.

Appearance of coating equipment. The resonance chamber sectional drawing of the coating apparatus for plate-shaped materials. The resonance chamber sectional drawing of a bulk material coating apparatus. FIG. 3 is a cross-sectional view of a resonance chamber of a rod-shaped and long material coating apparatus. Example of pattern coating.

Explanation of symbols

1 transducer 2 transducer (magnetostrictive ultrasonic transducer)
3 Resonant chamber 4 Plate-like material to be coated 5 Load 11 Metal or ceramic ball 12 Coating powder 13 Resonant chamber 14 Protective ring 15 Material to be coated 16 Load (cover)

Claims (5)

An oscillator having an automatic frequency adjustment function, a transducer that generates ultrasonic waves, a vibrator that transmits vibrations of the transducer, a cylindrical resonance chamber, and whether the resonator chamber is disposed in a lid shape A metal material to be coated disposed in a resonance chamber, and a metal or ceramic ball and a metal or ceramic powder are placed in the resonance chamber, and at least the ball and the powder are The resonant chamber is vibrated by applying a high-frequency sound wave or ultrasonic wave adjusted to the resonance frequency f when loaded in the loaded state , and the ball and the powder collide with the metal material to be coated. There is adapted to be performed, the resonance frequency f when the load is at least the Coating apparatus characterized by and a Lumpur and the powder is a frequency calculated based on the approximate expression (1) representing the relationship between the resonance frequency f ₀ at the time of no load in a state of not being charged.
Here, M _C is the weight of the resonance chamber, M _B is the total weight of the ball and the powder was placed in a resonance chamber, G _S is overall rigidity of the oscillator (N / m). The coating apparatus according to claim 1, wherein a height h dimension of the resonance chamber satisfies the following formula (2).
Here, C is the speed of sound (m / s) in the material constituting the resonance chamber. A metal or ceramic ball and metal or ceramic powder are placed in the resonance chamber, and the target metal material pre-coated with metal or ceramic powder by patterning is placed in the resonance chamber or the resonance chamber. The resonance chamber is vibrated by applying a high-frequency sound wave or an ultrasonic wave adjusted to the resonance frequency f at the time of loading in a state where at least the ball and the powder are loaded. Coating is performed by causing the ball and the powder to collide with the metal material to be coated, and the resonance frequency f at the time of loading is at least that the ball and the powder are not charged. the relationship between the resonance frequency f ₀ at the time of no load in the state A coating processing method characterized in that the frequency is calculated based on the approximate expression (1) representing:
Here, M _C is the weight of the resonance chamber, M _B is the total weight of the ball and the powder was placed in a resonance chamber, G _S is overall rigidity of the oscillator (N / m).   The coating apparatus according to claim 1, wherein the coating process is performed using a magnetic powder or a mixed powder of a non-magnetic powder and a magnetic powder as the powder.   The coating treatment method according to claim 3, wherein the coating treatment is performed using a magnetic powder or a mixed powder of a non-magnetic powder and a magnetic powder as the powder.