JPS5842739A - Cu alloy for spectacle frame - Google Patents

Abstract

PURPOSE:To provide fine pinkish gold color tone, superior cold workability and softening resistance by using a Cu alloy contg. specified amounts of Ni, Sn, >=1 kind among Mn, Fe and Co, and Ti and/or Si. CONSTITUTION:The composition of a Cu alloy for the frame of a pair of spectacles is composed of, by weight, 8-22% Ni, 2-4% Sn, 0.1-1% >=1 kind among Mn, Fe and Co, 0.1-1% Ti and/or Si, and the balance Cu with inevitable impurities. Ni and Sn are added to provide a fine pinkish gold color tone, and other metals are added to provide high strength and softening resistance.

Description

[Detailed Description of the Invention] The invention provides eyeglasses that have a beautiful golden color tone with a slight pink (light red) tinge, as well as excellent cold workability, high strength, and resistance to softening against heating. This invention relates to a CU alloy for frames.

In the past, eyeglasses were treated as medical equipment, but in recent years, more and more emphasis has been placed on them as accessories, and the decorative value has been sought not only in the design but also in the color tone of the frame material itself. It is becoming.

For this reason, the unique color tone of the metal is an important element in the properties required of metal materials for eyeglass frames, and in addition, it is possible to make the frame thinner to achieve light weight. High strength, drawing, rolling,
Excellent cold workability, which allows for easy cold working such as drawing and swaging, and excellent brazing properties, which make it easy to assemble manufactured parts, are also essential. there were.

In general, Cu alloys, which are colored alloys, vary in color tone depending on the type of alloying element, and are preferred as decorative materials because of their soft luster. Furthermore, copper alloys have excellent cold workability and can be given excellent strength through processing, so they have traditionally been used for eyeglass frames. It was also a metal material.

Conventionally, Cu alloys used for eyeglass frames include nickel silver and brass, but in eyeglass frames made of such alloys, brazing is sometimes performed on parts that are exposed to high temperatures, especially When brazing hinges and blow tips, parts may soften due to heat and cause problems such as deformation, or in order to deal with such problems, increase the weight to compensate for the decrease in strength of parts that are prone to softening as mentioned above. The need for it has been shunned, and its use has been drastically reduced. In place of such nickel silver and brass eyeglass frame materials, N1-based alloys have become common as metal eyeglass frame materials.

N1-based alloys have a high softening temperature, so they are difficult to soften due to brazing, and their cold workability is also inferior to copper-based alloys.
Due to its excellent strength, it has become widely used as a material for eyeglass frames in recent years, but because the color tone is limited to white, it cannot satisfy the preferences of various users. The problem was that there was no

From the above-mentioned viewpoints, the present inventors have discovered that not only can an arbitrary color tone be produced, but also excellent cold workability is achieved,
In addition, in order to obtain a metal material for eyeglass frames that has high strength and does not soften even during brazing operations, we focused on Cu alloys, which can be produced in a variety of colors, to create a material with excellent elegance as a material for eyeglass frames. As a result of conducting research to find a Cti alloy that has a good color tone and does not soften due to heating during brazing, the following findings (a) to (C) were obtained. ) When CuiCNi is dissolved in solid solution, the copper color changes to a whitish color due to the increase in its amount, but if the amount of N1 is selected appropriately, the soft color characteristic of CU can be maintained. In addition, when this is further alloyed with Sn, an alloy having a delicate and beautiful color tone, such as a pale reddish golden hue with an extremely elegant and soft taste (warm taste), can be obtained.

b) Adding T1 or Sl to the Cu alloy and further adding M
When one or more of n, Fe, and CO are added, Ti or Sl becomes the transition metal Mn, Fe, Co, and N.
The interaction with 1 forms fine intermetallic compound particles in the alloy, so dispersion strengthening by these particles not only improves strength and softening resistance, but also
In addition, the improvement in strength due to the effect of grain refinement is added, and in addition, when reheated to a high temperature after cold working, polycrystalline grains generally increase in size due to secondary recrystallization, resulting in a decrease in strength. However, the presence of the dispersed particles suppresses the coarsening of crystal grains and minimizes the decrease in strength due to coarsening.

C) The above-mentioned fine dispersed particles of intermetallic compound exist extremely stably even at high hot working temperatures (800~B), prevent grain size from increasing, and improve hot workability. Ability to process alloy materials efficiently and economically.

Therefore, this invention was made based on the above knowledge, and contains Cu, N1: 8 to 22% (hereinafter % is weight %), and Sn: 2%.
~4%, by containing 0.1 or more of Mn, Fe, and CO: 0.1 or more of Mn, Fe, and CO. ~1
．． By containing 0% and further containing 0.1 to 1.0% of one or more of T1 and Sl, the alloy for eyeglass frames can be provided with high strength and excellent softening resistance. It is characterized by the fact that it has been constructed as follows. In the Cu alloy for eyeglass frames of the present invention, Ni, Sn, Mn, Fe, Co, Ti
, and the reason why the composition ranges of the Sl component are limited as described above will be explained.

(a) Ni The N1 component has the effect of solidly dissolving in Cu to increase its strength and at the same time improve its corrosion resistance. And Cu
When KNi is dissolved in solid solution, as its amount increases, the alloy changes from a so-called copper color to a whitish color, and when it exceeds 25%, it becomes a white alloy. Therefore, in order to maintain the soft color characteristic of Cu, and to create a composition that could obtain a beautiful golden color with a slight reddish (pink) tinge when Sn was added, Ni The content of the ingredients was limited to 22 inches or less.

On the other hand, if the N1 content is less than 8%, the required strength cannot be obtained, so the content is limited to 8 to 22%.

(b) When Cu containing 22% or less of the 5n N1 component is further alloyed with Sn, it has an extremely elegant and soft (warm) pale reddish golden hue, which has a delicate and beautiful color tone. However, in order to produce such a color tone, it is necessary to add Sn with a coefficient of 1 or higher.On the other hand, the Sn component is extremely effective as a solid solution strengthening element, and its content is Cold workability and mechanical properties are improved by increasing the However, if Sn content exceeds 4%, it will lower the softening temperature, and if mechanical properties are taken into account, if the content is less than 2%, it will be necessary for eyeglass frame materials. It may become impossible to obtain sufficient strength,
Its content was limited to 2-4%.

(c) Ti, Si, and Mn, Fe,
C.

These elements contribute to the refinement of crystals and increase their strength.

As mentioned above, T1 or Sl is extremely effective in improving the softening resistance, and also has many useful effects such as improving the hot workability of the alloy.
In order for the fine dispersed particles of intermetallic compounds generated in the alloy to exhibit the desired effect due to the interaction with n, Fe, C'o and N1, one or both of T1 and Si must be added. 0.1% or more, and Mn.

It is necessary to add at least 0.1% of one or more of Fe and Co in combination; on the other hand, even if each of them is added in an amount exceeding 1 part, no further effect can be expected, and the opposite is true. Since these elements impair cold workability, the content of these elements was limited to 0.1 to 1.0%.

In addition, Au, 'Ag, Pd, Pt'
Although it is known that elements such as There is no problem in adding it for the purpose of achieving similar color tone as long as the content is within the range of 1.0% or less.

Next, the Cu alloy of the present invention will be explained by way of examples and in comparison with a conventional example.

Examples Alloys 1 to '7 of the present invention having the compositions shown in Table 1
and conventional alloys 1 to 3 were melted in a high-frequency induction heating furnace, mold-cast and cut, cold-rolled to a thickness of 2 mm, annealed at 750°C for 2 hours, and then further cold-rolled. was added to make a final plate of 1.2 mm.

Regarding the samples taken by multiple cuts from this plate, the as-cold-rolled material and the one heat-treated at 700°C for 20 seconds,
Table 1 also shows the tensile strength test results for those annealed at 750°C for 2 hours. From the results shown in Table 1, the alloys of the present invention exhibit remarkable high strength even when cold worked. It is clear that this can be obtained.

Further, the heat treatment condition of 20 seconds at 700° C. is a simple method for evaluating softening resistance against brazing. Furthermore, it is almost impossible to heat-treat the nickel silver and silver bronze used for springs, which have traditionally been used as Cu alloys for eyeglass frames, under these conditions.

It is clear from the results in Table 1 that the
It can be seen that this greatly limits its use as a frame material for eyeglasses.

On the other hand, the alloy of the present invention does not soften at all and maintains extremely high strength, but the limitations caused by brazing are: a) It is necessary to increase the amount of material used to compensate for the decrease in strength due to brazing; It is clear that it is possible to completely avoid the following constraints, b) design constraints resulting from a) above, C) constraints that require an increase in material costs, and d) functional constraints due to increased weight. .

Furthermore, the results shown in Table 1 show that even when completely softened by annealing at 750° C. for 2 hours, the alloy of the present invention has considerably high strength.

As mentioned above, the CU gold alloy of this invention has a beautiful color tone, excellent cold workability, high strength, and especially excellent softening resistance, so it can be used in eyeglass frames that require these properties. In this case, it exhibits extremely useful performance.

Applicant: Mitsubishi Metals Corporation Agent Tomi 1) Kazuo

Claims (1)

[Claims] Contains N1: 8 to 22%, sn: 2 to 4, and contains one or more of Mn + Fe and CO20.1 to 1.0%, Furthermore, it is characterized by containing one or two of T1 and Sl: 0.1 to 1.0%, and having a composition consisting of Cu and unavoidable impurities: residue (hereinafter referred to as "duplex content"). Cu alloy for eyeglass frames.