JPS60110855A - Manufacture of decorative parts - Google Patents

Abstract

PURPOSE:To attain decorative parts each having combined reddish brown and golden yellow color tones by applying specified stress to the desired portion of the surface of a Cu-Al-Ni alloy having a prescribed composition. CONSTITUTION:An alloy plate consisting of 12-15wt% Al, 1-5wt% Ni and the balance Cu is subjected to soln. heat treatment, and it is quenched in a refrigerant. The color tone of the plate during the quenching is golden yellow, and when the plate is taken out and exposed to room temp., it turns reddish brown. Stress between the yield point of the martensite phase of the alloy and below the breaking point is applied to the desired portion or the whole of the surface of the alloy plate after the quenching by stamping or other method, and a martensite phase produced by the stress is left in the portion. The stress applied portion turns golden yellow, and other portion remains reddish brown.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for manufacturing decorative parts, and more specifically, the present invention relates to a method for manufacturing decorative parts, and more specifically, the present invention relates to a method for manufacturing decorative parts, and more specifically, the present invention relates to a method for manufacturing decorative parts, and more specifically, a process for discoloring the BJ portion or the entire surface of a base material having a red color to a golden yellow. The present invention relates to a method for manufacturing decorative parts.

[Technical background of the invention and its problems]

Traditionally, gold-colored decorative parts have been manufactured from pure gold, gold alloys, copper-zinc alloys called imitation gold, copper-tin alloys, copper-aluminum alloys, or on the surface of certain base materials. Gold plated, titanium nitride C
, V, D method (chemical vapor deposition method) to perform surface treatment such as coating formation.

Also, pure copper itself is widely used for the red decorative parts.

By the way, the background is red and there are golden letters inside.
Decorative parts with embossed numbers or various patterns are attracting attention because they give an extremely gorgeous impression and have a great decorative effect.

In order to manufacture this kind of decorative parts, a base material of pure silver of a reddish color is used, and only the desired areas on the surface of this base material where golden letters, numbers, patterns, etc. are to be formed are to be formed on the surface described above. Processing is being applied.

However, such a method is not industrially advantageous because the manufacturing process is complicated and the manufacturing cost increases.

[Purpose of the invention]

The present invention aims to provide a method for manufacturing a decorative component having a color tone that is a combination of reddish yellow and golden yellow. This method utilizes the change in color tone accompanying the martensitic phase transformation of the -Ni alloy.

That is, the method for manufacturing decorative parts of the present invention includes A112 to
A stress equal to or higher than the yield point of the martenzite phase of the alloy is applied to the desired portion or the entire surface of the alloy containing 15 wt. Alternatively, it is characterized by allowing a stress-induced martensitic phase to remain on the entire surface.

Alloys with two compositions have a transformation temperature determined by their composition. The matrix of the alloy is amber in color.

When the above alloy of a certain composition is deformed by applying external stress at a temperature higher than the transformation temperature of the alloy, the relationship between the stress and the strain of the alloy (stress strain curve) is as shown in the figure. In a relationship.

When stress is applied to the alloy, the color tone of the area where the stress is applied changes as follows.

In the figure, A-+B is the elastic deformation region of the matrix, and there is no change in color tone during this process, and the alloy exhibits a reddish color.

If stress is further applied beyond the yield point of the matrix B, a martensitic phase will precipitate in the matrix. That is, B
→The process of C is the growth region of the martensitic phase, and the parent phase disappears at the 0 point.

Therefore, during this process, the alloy exhibits a color tone that is a mixture of the reddish color of the matrix phase and the golden color of the martensitic phase.

The process C-)D in which stress is further applied is an elastic deformation region of the martensitic phase, and at point D, the martensitic phase loses its elastic deformation. That is, point D is the yield point of the martensitic phase.

DIE is a permanent deformation region of the martensitic phase, and point E is its breaking point.

C-) D, In the process of DIE stress application, the color tone of the alloy is golden yellow with martensitic phase.

In this way, when a predetermined stress is applied to the surface of the above-mentioned alloy, the color tone at that location changes from a dark red to a golden yellow.

However, what should be noted here is that in the elastic deformation region of the martensitic phase of COD, when the applied stress is removed, the stress-induced martensitic phase disappears via, for example, C'→F. The result is that the golden hue disappears. Then, as the stress is removed, a parent phase precipitates in the martensitic phase (F-+G), and finally the martensite phase disappears (point G), and a single parent phase (G
-+H), and the color tone changes according to the phase □ transformation.

However, in the permanent deformation region of the martensitic phase of D-+E, the above-mentioned situation does not occur, and the stress-induced martensitic phase remains as it is even after the stress is removed, and the golden color does not disappear.

The method of the present invention was developed by focusing on the correlation between stress and color tone change.

That is, on the surface of the alloy having the above composition, if you want to change the color to golden yellow, or if you want to make the entire surface golden yellow, apply a coating that is higher than the yield point (D point) of the martensitic phase (point E) or the entire surface.
A stress less than point) is applied to cause the stress-induced martensitic phase to remain at the location. If you do this,
Even after the stress is removed, the area retains its golden color. The stress may be applied by any method such as coining, compression, tension, and scratching.

In the composition of the alloy used, A7! When it is less than 12 times N%, the deformation behavior as shown in the figure does not occur, but deformation occurs normally, and the color tone is only K, a golden color called aluminum gold. Also 1
If it exceeds 5% by weight, no martensitic phase will occur and the color will usually be silvery gray with a metallic tone. Ni functions as a stabilizing component of the stress-induced martensitic phase and is maintained within the range of 1 to 5 weight. If the amount of Ni added is outside this range, problems such as the deformation behavior shown in the figure will not occur and the color will be golden yellow, or the color tone will become silver gray due to the decolorizing effect of a large amount of Ni will occur. .

In addition, regarding the composition of the alloy, consideration must be given to the usage environment of the intended decorative parts (generally - 150 to 50'C, considering the width), and care should be taken to ensure that the transformation temperature is within the above temperature range. Bye. The alloy with the above composition has a transformation temperature of 1200 to 4
00'IC.

Furthermore, the stresses corresponding to the yield point and the breaking point are automatically determined once the composition of the alloy is determined, and are arbitrarily selected and applied based on the relationship of the alloy used.

Such an alloy is manufactured as follows.

That is, an alloy having the composition as described above or powder of each component is melted in vacuum, and the melt is cast into a mold to form an ingot. This ingot is hot forged in order to eliminate casting defects or homogenize the material.

Perform processing such as hot rolling. The obtained material is heated, for example, in an Ar atmosphere at 850 to 1050°C for 1 to 5 hours.
Solution-treated him, this is rapeseed oil.

Quench and rapidly cool using Freon refrigerant. at this point
A martensitic phase is formed in the alloy and the color i11. 'J
is golden in color. Then, when this is brought back to room temperature, the alloy becomes a dark red color.

[Embodiments of the invention]

A/: 14.5 major prize%, Ni: 3.0 major prize%,
An alloy consisting of 82.5% by weight of Cu was vacuum melted at 1300°C, and the melt was cast into a mold to form an ingot.

This ingot was hot-forged and hot-rolled, and then sliced into plates.

This plate material was subjected to solution treatment in an Ar atmosphere at 950°G for 1 hour, and then quenched in a Freon refrigerant at -40°C.

The color of the plate material during quenching was golden, but this was
When I took it out, the color became a bright red.

Next, a steel "Y" stamp was brought into contact with the surface of this board at room temperature and stamped with a pressure of 40k19/-. When the stamp was removed, the surface of the board was 1T.
``Only the parts of the letters were golden yellow, and the rest were reddish brown.

〔Effect of the invention〕

As is clear from the above explanation, the method of the present invention can make a desired part of the alloy surface of a predetermined composition a golden color by simply applying stress to the desired part, and the process can change the color from reddish to golden yellow. Its industrial value is great because it makes it possible to manufacture colorful decorative parts extremely easily and therefore at low cost.

[Brief explanation of the drawing]

The figure shows Cu-AA' used as a base material for decorative parts of the present invention.
It is a figure which shows an example of the stress strain curve of a -Ni alloy. Big brother hippo □

Claims (1)

[Claims] Aluminum 12-15% by weight, nickel 1-5% by weight
, applying a stress equal to or higher than the martensitic phase yield point of the alloy to a desired portion or the entire surface of the alloy, the remainder of which is copper, to cause the stress-induced martensitic phase to remain in the desired portion or the entire surface. A method for manufacturing decorative parts, characterized by: