JPS604241B2 - Metal moldings for surface coating materials - Google Patents

Description

[Detailed description of the invention] The present invention relates to a metal molded body used as a surface covering material.

More specifically, the present invention relates to a high-purity metal molded body used as a surface coating material by dry plating and a method for producing the same.

In recent years, surface coating methods using physical means such as vacuum evaporation or ion plating methods using electron beams, and sputtering methods have been introduced as plating methods to replace wet plating methods that use hexavalent chromium in particular due to environmental pollution. The so-called dry plating method is attracting attention. In this dry plating method, thermal or electrical energy is applied to the metal to be adhered to the surface of the object to be plated, either in powder form, or in the form of a rod or plate (hereinafter referred to as target). This is a method of ionizing metal or scattering it in atomic form and attaching it to the surface of the object to be plated.
It is increasingly being used for electronic industry parts and for surface coatings such as plastics.

The present inventors have been conducting research on the molding of targets used in dry plating, especially sputtering methods, and found that by pressurizing the metal powder to be molded under certain conditions, it is extremely suitable for use as a target. Discovered that it was possible to obtain a metal molded body. did.

The metals used to form plating films in dry plating include Au, Ag, and Pt, as well as Zn, Cd, W, Ti, and C.
Cr, Ni, Mn, Cr, etc. Among these, Cr is widely used for plating industrial machinery parts and electronic parts because the surface coated with it has extremely excellent wear resistance or chemical resistance. has been done.

Particularly those used for plating electronic industrial parts require high purity metals. In order to obtain high-purity metals such as high-purity chromium metal, a chromium salt solution can be obtained by electrolysis, so-called electrolysis, a chromium salt solution is extracted and purified using a certain type of organic solvent, and a purified chromium salt solution is obtained, or There are methods such as oxidizing the chromium salt obtained from this solution and then ringing to obtain metallic chromium, and further burning chromic acid or chromic acid anhydride and then ringing.

．． In the present invention, any of the metals mentioned above and those obtained by any of the methods can be used.

In the present invention, metallic chromium obtained by extraction and purification using the above-mentioned organic solvent is particularly preferred. The solvent used for solvent extraction is appropriately cooled depending on the type of metal to be extracted.

For example, iron, molybdenum, etc. are phosphorus compounds such as trioctyl phosphate, tributyl phosphate, di-2-ethylhexyl phosphate, etc., and cobalt, etc. are amines such as tri-normaloctylamine, trisooctylamine tolcaprylamine, etc. Use.

By removing metals coexisting with chromium using such a solvent, a solution containing extremely high purity chromium can be obtained. Therefore, chromium powder metallized by oxidation and ring treatment using this solution has high purity and becomes a good target.

Particularly when obtaining a metallic chromium target, since metallic chromium is hard and brittle, it is extremely difficult to cut an ingot to obtain a desired molded body. Furthermore, when metallic chromium is obtained by electrolysis, the metallic chromium peeled off from the electrode plate retains the shape of a molded body, but it is not always possible to obtain the required thickness and size. The present invention is characterized in that metal powder is pressurized and molded. Pressure molding of metal powder is performed by {1-heat pressing, so-called hot press, ■mechanical pressurization in which a cylindrical object is filled with metal powder and compressed with a piston from the top and bottom or from the left and right, and [3} rubber. This can be done by a method such as a so-called rubber press, in which metal powder is sealed in a bag-like material, placed in water filled with a pressure-resistant container, and water is pressurized into the container.

However, the product obtained by the method {1) is inevitably expensive, and the method '2} is expensive when obtaining a molded product with a large thickness.
This is not a preferred method because lamination may occur in the molded product or cracks may occur when the resulting molded product is heated.

In the present invention, the pressurizing method [3] is preferred.

In the 3-piece method, a molded body of the desired shape can be obtained by appropriately selecting the shape of the bag-like material such as rubber that encloses the metal powder, and since the entire molded body is coated with heat, it is extremely dense. or,
A thermally stable molded body can be obtained.

Furthermore, when a high purity metal is used during molding, the moldability is extremely good due to the ductility of the high purity metal.

The pressurizing pressure of the above-mentioned pressurizing method {3', that is, the rubber press method, varies depending on the type of metal to be press-molded, but is 500 to 5,500 k9/m.

Further, the pressurization time is not particularly limited, but 5 to 120 minutes is sufficient. Further, especially when a target used for sputtering contains oxygen, when plating is performed using the target, oxidation of the coated surface of the object to be plated occurs, making it impossible to obtain a desirable surface.

Therefore, when molding the target, it is preferable to use degassed metal powder as necessary.

The metal is degassed by a conventional method such as heating the metal in a cyclic atmosphere. Of course, after molding, the metal molded body may be degassed by the operations described above.

The molded body obtained by pressure molding is subjected to post-processing such as forming and polishing to produce a product.

According to the present invention, it is possible to obtain a highly pure and strong target for dry plating, and the obtained target is particularly suitable for use in sputtering.

Next, the present invention will be explained in detail with reference to Examples.

Example 1 Chromium chloride obtained by chlorinating ferrochrome containing 61.6% Cr, chlorine gas was passed through an iron chloride solution to convert iron ions into trivalent iron ions, and then a rotating disk type countercurrent extraction device (4
The iron chloride was removed by countercurrent contact with the toluoctyl phosphate kerosene solution using a chromium chloride solution.

Next, the chromium chloride solution was further purified by contacting it with a tri-n-octylamine-xylene solution using a mixer-settler countercurrent extraction device (two stages), and the solution was dropped into a furnace in which hydrogen was burned to simulate a forgery. This was further reduced in vacuum using carbon at about 1400 qo and further reduced at about 1500°C in a hydrogen stream to obtain a purity of 99.97% (CO
．． 01%, Feo. A metal chromium powder (20 mesh or less) containing 0.01% and 0.01% of others was obtained. This metal. Fill a chromium powder into a rubber bag with a thickness of approximately 10 mm and a diameter of 200 mm, place it in a pressure-resistant container of approximately 0.5 mm filled with water, and press the water into the container to make a 4000 k9/cm. and left for 5 minutes. The molded product taken out from the rubber bag after pressurization had an apparent density of 6.2 min/lump.

This molded product was incubated for 2 hours at 1,600 qo in a hydrogen stream, but no cracks were formed and it remained solid.

The surface of the molded body obtained in Example 1 was cut and polished using a lathe, and when used as a target for surface coating by sputtering on the surface of Marin, a beautiful coated surface was obtained.

Claims (1)

[Claims] 1. A chromium salt solution obtained by extracting and purifying a solution containing a chromium salt with an organic solvent, or by oxidizing the chromium salt obtained from the solution and ring-forming the obtained chromium oxide. A chromium molded body for surface coating by pressure molding of high-purity metallic chromium using sputtering vapor deposition, ion vapor deposition, or electronic vapor deposition. 2. The molded article according to claim 1, which is made of degassed metal chromium. 3. The molded article according to claim 1 or 2, which is molded by a rubber press method.