JPH03258207A - Making of noble metal goods for ornament - Google Patents

Abstract

PURPOSE:To heighten the working efficiency of a workpiece and to make the finishing thereof uniform and beautiful by eliminating the bend working and braze working of the workpiece after the press working thereof, by a method wherein Cu or Cu-alloy member as a core material is inserted into a Au or Au-alloy tube, and they are made a false complex by drawing-work, and this false complex is wrought in a desired shape, following which the core material is dissolved in an acid and removed. CONSTITUTION:A Cu bar 2 of which the periphery is coated with oil is inserted into a K18 tube 1, and they are drawn by a drawing bench, and are made a false complex. After that, with a deforming roll, the false complex is wrought in a desired shape, and is cut off. Such a workpiece is immersed in nitric acid solution, and a Cu core material is dissolved and removed. In this way, a hollow parts 3 can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing precious metal articles for jewelry such as bracelets, necklaces, tie pins, compacts, and rings.

[Conventional technology]

Recently, some precious metal items for jewelry have been made hollow to increase their volume in order to give them a sense of weight.

A conventional example of the manufacturing method will be described below with reference to the drawings.

Figure 3 (a) is a plan view of the pressed material, Figure 3 (c) is a perspective view of the material being bent, and Figure 3 (C) is a perspective view of the material being bent.
) is a perspective view of the product. A precious metal plate with a thickness of about 0.5+++m is punched out as shown in Fig. 3 (a), and after the bottom shape and drawing processing are performed, bending processing is performed to obtain the shape shown in Fig. 3 (b). ), and then braze the joints (arrows) to form the third
It is finished as a precious metal product for jewelry as shown in Figure (C).

[Problem to be solved by the invention]

However, according to the above-mentioned conventional technology, bending must be performed after press forming and drawing, and this process requires considerable precision, and it is extremely difficult to process complex patterns and shapes. There is. ■Brazing involves the problem of poor workability since brazing between the parts and the ends of the plate requires machining. Furthermore, there is a problem in that this brazing process is very difficult because the plate thickness of the material is thin, so it is very difficult to process the brazing part and the plate end. ■This brazing process causes the product to soften, making it impossible to maintain the strength suitable for jewelry, which requires thickening the material, resulting in an expensive product. be.

■Also, since the brazed parts have unevenness and discoloration due to heat, polishing, puff finishing, etc. are required to correct them, and these corrections are very time-consuming. It's work. ■Even for products completed through such work, there is a problem in that the incidence of defective products is extremely high due to the difficult work described above.

[Means to solve problems]

The present invention provides a method for adding Cu or C to Au or Au alloy pipes.
U alloy, Fe or Fe alloy or Ni or Ni alloy is inserted as a core metal material, followed by drawing processing to make a pseudo-composite material, and after processing this pseudo-composite material into a desired shape, this pseudo-composite material is The product is characterized in that by dissolving and removing the core metal material with acid, only the outer Au or Au alloy is obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1st implementation exception diameter 15mm, inner diameter 14mm, 3mm, length between 500K
18 (75+!Au-2Au-25XAχCu alloy) Pipe 1 with a diameter of 14 mff with oil applied to the outer periphery
1. A Cu rod 2 with a length of 700 mm was inserted and pulled out to a diameter of 1.2+n+ using a draw bench to obtain a pseudo composite material. Subsequently, it was processed into the shape shown in FIG. 1(a) using a deformed roll, and then cut into the shape shown in FIG. 1(b).

The thus processed product is immersed in a nitric acid solution to form a core metal material.
By dissolving and removing u, a hollow part 3 as shown in FIG. 1(C) was obtained.

Second implementation exception diameter 5.1nm, inner diameter 4.4+nm, length 500m
22 (91,7χA u -5XCu -3,3
χAg alloy) A Fe pipe 1 with a diameter of 4.2+++m and a length of 600IllIll coated with carbon powder on the outer periphery.
Rod 2 was inserted and pulled out to a diameter of 3.8 m using a draw bench to obtain a pseudo composite material. Next, the thickness is 2.2++ using a rolling mill.
+n, after rolling to a width of 5.4 mm, Fig. 2 (a)
As shown in the figure, it was punched out using a press die with a diameter of 6.5+nm,
It was formed into the shape shown in FIG. 2(b), and then processed into the desired shape using a press bottom shape.

The processed product thus shaped was immersed in hydrochloric acid to dissolve and remove Fe of the core metal material, thereby obtaining a hollow part 3 as shown in FIG. 2(C).

〔Effect of the invention〕

According to the present invention described in detail above, Cu or Cu alloy, Fe or Fe alloy, or Ni or Ni alloy is inserted into Au or Au alloy pipe as a core metal material, and then drawing is performed to form a pseudo composite material. After processing this pseudo-composite material into a desired shape, the outer Au is removed by dissolving and removing the core material of this pseudo-composite material with acid.
Alternatively, by using only the Au alloy, (1) there is no bending process after press forming, which was previously required, resulting in a clean finished product and fewer work steps. ■Brazing has excellent workability because there are no spots, and has the effect of creating a uniform and beautiful finish on the product.Furthermore, brazing has the effect of eliminating the need to remove flux afterwards. ■Because there is a core metal material in the press molding darkness, the workpiece is not hollow, so even complex shapes can be formed accurately, and the wall thickness of the product can be thinned. It has the effect that it can.

[Brief explanation of drawings]

Figures 1 (a) to (C) are process diagrams showing the first embodiment;
Figures (a) to (C) are process diagrams showing the second embodiment, and Figure 3 (
a) to (C) are process diagrams showing a conventional example. l...Au or Au alloy pipe 2...core metal material 3...hollow part

Claims (1)

[Claims] 1. Insert Cu or Cu alloy, Fe or Fe alloy, or Ni or Ni alloy as a core metal material into an Au or Au alloy pipe, and then draw it to make a pseudo-composite material, and make this pseudo-composite material into the desired shape. After processing into shape,
A method for manufacturing a precious metal article for jewelry, characterized in that the core metal material of this pseudo composite material is dissolved and removed with acid to obtain a product with only the outer Au or Au alloy.