JPS62136576A - Method and apparatus for surface treatment of magnesium or magneium alloy - Google Patents

Abstract

PURPOSE:To improve wear resistance and to obtain a surface layer having good electrical conductivity and IR radiation characteristic by depositing a metal having good electrical conductivity by evaporation on an anodized Al film formed on the surface of a base material consisting of Mg (alloy). CONSTITUTION:The Mg or Mg alloy having a required shape is subjected to a blasting treatment and thereafter an Al film is formed thereon to a prescribed thickness by a dry plating method. The Al film is anodized. The Mg (alloy) formed with the anodized film and a metallic film source having good electrical conductivity are disposed in a vacuum vessel in which 10<-4>-10<-6>Torr pressure is maintained. An energy beam having 10<2>-10<7>watt/cm<2> intensity is then directed to the metallic film source and several kinds of thin metallic films having the good conductivity are successively deposited on the surface of the Mg (alloy).

Description

[Detailed Description of the Invention] [Industrial Application Field J This invention is for heat control in equipment used in space equipment! The present invention relates to a method and apparatus for surface treatment of magnesium or magnesium alloy in order to achieve corrosion resistance and good conductivity.

As is well known, magnesium or magnesium alloys are chemically very active and easily react with various chemicals. Just as steel rusts and copper discolors, magnesium or magnesium alloys An oxide film also forms on the surface of the alloy.

Magnesium, or magnesium alloys, is electrochemically base and can be sacrificially corroded by other metals, forming local batteries when used in contact with other metals, especially when wet or humid. Therefore, surface treatment technology can be considered as a means to completely protect the surface of magnesium or magnesium alloy from corrosive environments or environments that form local batteries1. Magnesium or magnesium alloy has the lowest specific gravity among all practical metals and is easy to process, so it has attracted attention as aerospace equipment becomes larger and lighter weight measures are increasing.
Establishment of surface treatment methods is required.

However, as mentioned above, magnesium 9 or magnesium alloy is electrochemically base compared to other metals, has poor corrosion resistance, and has poor wear resistance, seizure resistance, thermal radiation property, and electrical conductivity. Usage is restricted.

Various surface treatment methods have been considered to improve these drawbacks, but none have been found that satisfy the above requirements.

Therefore, establishing a complete surface treatment method for magnesium or magnesium alloys will open up a path that has hitherto been restricted and will contribute to production technology.

[Means for solving problems]

Surface treatment method for space equipment made of magnesium or magnesium alloy according to the present invention and its vctif
As a result of extensive research, aluminum of the required thickness was formed on the surface of a substrate made of magnesium or a magnesium alloy using a dry film forming method.

It has been discovered that the above object can be achieved by subjecting the formed aluminum film to an anodic oxide film by anodic electrolysis, and then performing vacuum evaporation of several kinds of conductive metals with the aid of laser light. It was.

[Effect]

In this invention, an aluminum film is formed on the surface of a base material made of magnesium alloy or magnesium alloy,
*, i Forms an oxide film, resulting in remarkable corrosion resistance Same as above. Next, in this invention, I coats the metal thin film with good conductivity, and coats the surface of the substrate made of magnesium or magnesium alloy with conductivity and It has excellent heat radiation characteristics.

〔Example〕

The present invention will be described in more detail below with reference to Example I.

Figure 1 6) to (f) show the processing method. The material (magnesium or magnesium alloy) (1) is first cleaned. Next, the plated surface is roughened by blasting. 9th, the aluminum dry process is performed. Ensure that the plating layer (21) is formed firmly. After that, aluminum plating (2) is performed by dry plating to a thickness of 10 to 30 μm. Here, the thickness of the aluminum plating gold is increased.

As is well known, during the next process of anodic oxidation, the film grows in the direction of the material, so this is to avoid any confusion.

After that, an anodic oxide film (3) is formed on the aluminum using either a sulfuric acid bath, an oxalic acid bath, or a chromic acid bath.

Figure 2 shows a cross section after forming a plating film on a magnesium or magnetic screw 1 um material (magnesium or magnesium alloy).
, +21 is a dry aluminum layer, (31 is an anodized film layer -+41. (51 is a metal film, and it is desirable to change the specifications for two uses.

For example, if corrosion resistance and infrared radiation properties are required, the first layer is made of nickel and the second layer is made of gold.

If necessary, the first layer should be made of copper, which has good electrical conductivity and infrared radiation properties.2. The second layer is gold.

Figure 3 shows a manufacturing apparatus for forming a metal thin film on the surface of the above magnesium or magnesium alloy. (6) is a vacuum vessel + (7) is a film source. (8) is a heater. (9) is a condensing lens, (11 is a mirror, +1υ
is the beam line and α2 is the energy source.

Magnesium above! Or a magnesium alloy with an anodic oxide film layer formed on the second side (1) in a vacuum container (6)
Put it in the tank and degas it until it reaches 01 to 10 Torr. After heating the film layer (7) and the above magnesium or magnesium alloy material to a predetermined temperature using the heater (8), the film source (7) is rotated.

A laser beam is oscillated from an energy source α2, a laser beam line αυ is reflected by a mirror α, and the laser beam line is converged by a condensing lens (9) and ν selectively irradiates the coating source (7).

In this way, the coating source (7) is heated to melt and evaporate.

A desired metal thin film is deposited on an anodic oxide film formed on the surface of magnesium or a magnesium alloy.

〔Effect of the invention〕

As is clear from the above explanation, according to the method and apparatus for surface treatment of magnesium or magnesium alloy of the present invention, the surface of the substrate made of magnesium or magnesium alloy has excellent abrasion resistance and good conductivity. Since it is relatively easy to apply a surface treatment layer with good infrared radiation characteristics, we are confident that applications that have been limited until now will expand further in the future, and that it will occupy an important position in aerospace equipment.

[Brief explanation of drawings]

Figures 1) to 2 are diagrams showing the treatment method of the present invention.
Figure 3 (9), which shows a cross section of the plated film, is a diagram showing a method for manufacturing a thin metal film. In the figure, (11 is the material (magnesium or magnesium alloy), (21 is the aluminum plating layer, (3) is the anodic oxide film layer, +41. (5) is the metal thin film, (6) is the vacuum container, ( 7) is the coating source, (8) is the heater, (9)
is the condenser lens - αq is the mirror, αυ is the beam line, αX5
is an energy source.

Claims (5)

[Claims] (1) In a surface treatment method for magnesium or magnesium alloy in a desired shape, blasting is performed as a pretreatment, and after this pretreatment, aluminum is formed to a desired thickness by dry plating, and then the aluminum film is coated on the aluminum film. An anodic oxide film is formed, and then the magnesium or magnesium alloy with the above-mentioned anodic oxide film and the magnesium alloy with good conductivity are separated from each other by a required distance in a vacuum container in the range of 10^-^4 to 10^-^6 Torr. a metal-based coating source, and selectively directing an energy beam having an intensity in the range of 10^2 watts/cm^2 to 10^7 watts/cm^2 to the metal-based coating source to heat it; Magnesium that is melted and evaporated to form the above-mentioned anodic oxide film, or magnesium that is characterized by sequentially depositing several kinds of thin metal films with good conductivity on the surface of a magnesium alloy.
Or a surface treatment method for magnesium alloy. (2) In the anodic oxide film treatment, 1.02 to 2 sulfuric acid
．． A method for surface treatment of magnesium or a magnesium alloy according to claim (1), characterized in that anodic electrolysis is carried out at an applied voltage of 10 to 25 V in a solution containing 0.4 mol of magnesium. (3) In anodizing film treatment, potassium titanate oxalate 0.10-0.13 mol, boric acid 0.10-0.
16 mol, citric acid 0.003 mol, oxalic acid 0.00
Applied voltage 80-1 in aqueous solution containing 4-0.012 mol
A method for surface treatment of magnesium or a magnesium alloy according to claim (1), characterized in that anodic electrolysis is carried out at 20V. (4) In anodizing film treatment, chromic anhydride 0.5
Claim (1) characterized in that anodic electrolysis is carried out at an applied voltage of 20 to 80 V in an aqueous solution containing ~1.0 mol.
2. Surface treatment method for magnesium or magnesium alloy as described in 2. (5) A vacuum container, a vacuum pump, a heater for heating, a container for storing a film source, a drive unit for rotating the container, a window for taking in a laser beam, an energy source for generating laser light, and a laser. A surface treatment device for magnesium or a magnesium alloy, characterized by a beam waveguide, a mirror that reflects the laser beam, and a condenser lens that converges the laser beam.