JPH0256995B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a composite material for eyeglass frame parts, and in particular, when manufacturing a composite material having an outer covering made of a Ni-Cr alloy, the inner surface of a pipe made of a Ni-Cr alloy is coated with Ni plating or Ni- After applying Sn 2-layer plating, a copper-based alloy core material is inserted, drawing is performed, and then diffusion heat treatment is performed to improve the plating layer.
Ni and Sn are diffused into the copper-based alloy of the core material to improve the springiness and strength of the core material, and to prevent oxidation during heat treatment of the Ni-CR alloy. As is well known, Ni-Cr alloys have good corrosion resistance, are white, and have good decorative properties, so they are widely used as materials for eyeglass frame parts. however
When a Ni--Cr alloy is used alone for eyeglass frame parts, there are problems such as insufficient springiness, high cost, and difficulty in processing. Therefore, traditionally
The outer cover is made of Ni-Cr alloy, and the core material is phosphor bronze.
It is known to use cladding materials made of beryllium copper, stainless steel, or the like for eyeglass frame parts. However, in this case, phosphor bronze,
When cladding beryllium copper or stainless steel with Ni-Cr alloy, there is a problem of cladding failure if the atmosphere is not properly adjusted, and especially when phosphor bronze is used as the core material, the springiness is insufficient. However, since phosphorus is contained in the core material, there is a problem that cladding becomes unstable.On the other hand, when beryllium copper is used as the core material, although it has good cladding properties, it is difficult to provide spring properties. It is necessary to perform heat treatment, and furthermore, when stainless steel copper is used as the core material, the cladding requires a high temperature, and furthermore, there is a problem that processing is more difficult than when using other metals. This invention was made in view of the above-mentioned circumstances, and in manufacturing a composite material for eyeglass frame parts whose outer sheath is made of a Ni-Cr alloy, it is possible to improve workability and at the same time stabilize the cladding. The object of this invention is to prevent cladding defects from occurring and to obtain a composite material with excellent springiness and strength. In other words, the method of this invention applies either Ni plating or Sn two-layer plating to the inner surface of a Ni-Cr alloy pipe, and then coats the inside of the pipe with two layers of Ni plating or Sn plating.
Cu-Ni-Sn-Zn alloy, Cn-Zn alloy, Cu-Ni-
A core material made of a copper-based alloy selected from among Zn alloys is inserted, and then subjected to drawing processing and diffusion heat treatment to diffuse the elements of the plating layer into the core material, By providing a plating layer in this way, it is possible to prevent damage during heat treatment.
It prevents oxidation of the Ni-Cr alloy to prevent clad defects, and diffuses Ni and Sn in the plating layer into the core material to improve the strength and springiness of the copper-based alloy core material. By using a copper-based alloy as the material, workability is also improved. The method of the present invention will be explained in more detail below. In the method of the present invention, first, as shown in FIG. Form layer 2. As the Ni-Cr alloy, it is desirable to use one containing about 3 to 18% by weight of Cr, with the remainder being Ni.
The inclusion of additive elements such as Ag is not prohibited.
Further, the thickness of the plating layer 2 is preferably about 10 μm to 40 μm. Furthermore, as the plating layer 2, Ni
When applying two-layer plating of
It is desirable to first apply Ni plating to the inner surface of the Cr-based alloy pipe 1 and then apply Sn plating on the Ni plating layer. After forming the plating layer 2 of Ni or Ni and Sn on the inner surface of the Ni-Cr alloy pipe 1 as described above, a core material 3 of a copper-based alloy is inserted inside it as shown in FIG. 1B. Make it fit. This copper-based alloy includes Cu-Ni-Sn-Zn alloy, Cu-Zn alloy, Cu
- Use one type selected from Ni-Zn alloys. All of these copper-based alloys have good workability, and also have good spring properties and strength. In this way, the copper-based alloy core material 3 is placed inside the plating layer 2.
After fitting, normally, as shown in Fig. 1C, a pipe 4 made of iron or the like for protection is fitted on the outside of the Ni-Cr alloy pipe 1, and a drawing process is performed to separate the plating layer 2 and the copper. The base alloy core material 3 is brought into sufficient contact with the base alloy core material 3. However, since the pipe 4 should be removed after the subsequent diffusion heat treatment, a material such as iron is used that will not be joined to the Ni--Cr alloy pipe 1 at the diffusion heat treatment temperature. Next, heat treatment is performed to diffuse Ni and Sn of the plating layer 2 into the copper-based alloy of the inner core material 3. Through this heat treatment, the copper-based alloy of the core material 3 becomes the plating layer 2.
As a result of diffusion, the Ni and Sn concentrations increase and become stronger, resulting in even higher springiness and strength.
are integrated, and the bond strength between them increases significantly. In addition, during this diffusion heat treatment, since the plating layer 2 exists on the inner surface of the Ni-Cr alloy of the pipe 1, oxidation does not occur on the inner surface of the Ni-Cr alloy, and there is no oxidation between the inner surface of the Ni-Cr alloy and the core material. The occurrence of cladding defects is effectively prevented. In other words, even if the atmosphere replacement during heat treatment is insufficient, crud defects due to internal oxidation can be effectively prevented. After performing the diffusion heat treatment in this way, the outer protective pipe 4 made of iron or the like is usually peeled off and removed by an appropriate means, and the remaining inner cladding material, that is, the Ni- A composite material having a Cr-based alloy as the outer sheath 1A and a copper-based alloy enriched with Ni or Sn as the core material 3A is subjected to wire drawing, press working, etc. as appropriate to make an eyeglass frame part. As mentioned above, in the final eyeglass frame composite parts, the copper-based alloy of the core material is
Because it is enriched with Ni and Sn, it has significantly superior springiness and strength. In particular, if the amount of diffused solid solution of Ni and Sn is set by the initial rough formation of the copper-based alloy and subsequent heat treatment so that the final copper-based alloy of the core material has a composition that exhibits so-called superelasticity, it is possible to performance will be better. Furthermore, since the composite material surface is made of a Ni-Cr alloy, it has excellent corrosion resistance and good brazing properties. On the other hand, in the manufacturing process, heat treatment is performed after forming a plating layer of Ni or Ni and Sn on the inner surface of the Ni-Cr alloy pipe, so as mentioned above, the inner surface of the Ni-Cr alloy pipe oxidizes and cracks. There is less risk of defects occurring, and the heat treatment atmosphere can be easily set. Furthermore, since the core material is a copper-based alloy, it is easy to process and has high productivity. Examples of the present invention will be described below. Example 1 Ni-10wt with outer diameter 45mm, wall thickness 1.3mm, length 400mm
Ni plating is applied to the inner surface of the %Cr alloy pipe to a thickness of 20μm, and then Cu-2wt%Ni- is applied inside the pipe.
A 11wt%Zn-5wt%Sn alloy rod was fitted, and then an iron pipe with an outer diameter of 49mm, an inner diameter of 45mm, and a length of 400mm was fitted on the outside of the Ni-Cr alloy pipe, and then drawn using a die with an inner diameter of 48.5mm. Ni after processing
The plating layer and the Cu--Ni--Sn--Zn alloy rod as the core material were brought into close contact. Further, diffusion heat treatment was performed in hydrogen at 700°C for 1 hour to diffuse Ni from the Ni plating layer into the Cu-Ni-Sn-Zn alloy serving as the core material. Next, a groove was cut into the outer iron pipe using a milling cutter, and the iron pipe was peeled off from the inner clad material, after which the clad material was drawn and further annealed and wire-drawn to produce a 2.6 mm wire rod. . Example 2 After applying Ni plating to a thickness of 20 μm on the inner surface of a Ni-Cr alloy pipe similar to that used in Example 1, Sn plating was further applied to a thickness of 20 μm on top of the Ni plating layer to remove Ni and Sn. A two-layer plating was applied, and then a Cu--Ni--Zn alloy rod similar to that in Example 1 was inserted and fitted inside the plating, and a 2.6 mm composite wire was obtained in the same manner as in Example 1. Comparative Example Example 1 except that the inner surface of the Ni-Cr alloy used in Example 1 was not plated with Ni.
A 2.6 mm composite wire was obtained in the same manner as above. When the cladding yield in each of the above Examples and Comparative Examples was investigated, the results shown in Table 1 were obtained. However, the cladding yield here is the weight of the composite material product obtained by excluding poor adhesion (defective cladding) from the composite material obtained in each example,
It is shown as a ratio to the total weight of the composite material obtained in each example.
In addition, at the final processing stage in each example and comparative example, the material was annealed at 600°C for 30 minutes and then pressed to a thickness of 0.5
Composite materials with a width of 4.5 mm, a width of 4.5 mm, and a length of 100 mm were obtained, and the spring values of each composite plate were investigated. The results are also shown in Table 1.
However, when measuring the spring value, check one end of the board, apply a load to the opposite end around the chuck, bend it 30 degrees, and then calculate the return angle θ when the load is removed and the board returns. Check θ/30×100
(%) values are displayed as spring values.

[Table] It is clear from Table 1 that the composite material obtained by the method of the example of the present invention has good cladding adhesion, high cladding yield, and excellent springiness. As is clear from the above description, according to the method of the present invention, it is possible to obtain a composite material for eyeglass frames that has excellent spring properties and strength, and also has good surface corrosion resistance.
In addition, various effects such as extremely low occurrence of clad defects and ease of processing can be obtained.

[Brief explanation of drawings]

FIGS. 1A to 1E are schematic cross-sectional views showing step-by-step an example of the method of the present invention. 1... Ni-Cr alloy pipe, 2... plating layer, 3
...Copper-based alloy core material.

Claims (1)

[Claims] 1 Ni plating on the inner surface of the Ni-Cr alloy pipe,
Either Ni or Sn two-layer plating is applied, and then Cu-Ni-Sn-Zn alloy, Cu
-Any one of Zn alloy or Cu-Ni-Zn alloy
1. A method for producing a composite material for eyeglass frames, which comprises inserting a core material made of a copper-based alloy, then subjecting it to drawing processing, and then subjecting it to diffusion heat treatment to diffuse the elements of the plating layer into the core material.