JPH1036927A - Alloy for cast parts of spectacles frame or the like, parts, and their production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an alloy for cast parts of the frame of spectacles, excellent in castability and capable of providing required strength, and cast parts produced by using this alloy. SOLUTION: The alloy for cast parts, e.g. of the frame 1 of spectacles has a composition consisting of, by weight, 20-42% zinc, 5-15% nickel, 3-10% manganese, 0.1-3% aluminum, and the balance copper with inevitable impurities. It is preferable that this alloy contains 0.5-3% tin. By using nickel silver as a base and adding aluminum and manganese, a new alloy for cast parts of the frame 1 of spectables, having age hardenability while maintaining the properties of nickel silver, can be obtained. By performing casting by a lost wax process and carrying out age hardening treatment, the parts having >=220 Vickers hardness can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alloy for a component having a complicated shape such as an eyeglass frame component and other accessories manufactured by casting, a component made of this alloy, and a method of manufacturing the component.

[0002]

2. Description of the Related Art In recent years, the decorative tendency of eyeglasses has increased, and there have been many cases in which eyeglass frames are decorated with connecting parts such as lens frames and hinge parts. FIG.
2 shows an example of such a decorative glasses frame, and FIG. 2 shows an enlarged view of the hinge part 4. As shown in FIG. A hinge part (armor) 4 is provided beside the lens frame 2 of the eyeglass frame 1, and the hinge part 4 and the vine 3 are connected by hinges. Here, the hinge part 4 has a decorative and complicated shape.
A jewel 5 is fixed to the hinge part 4. In the examples shown in these figures, the shape of the hinge part 4 is complicated, so that it cannot be manufactured by the press forming method. Therefore, the hinge part is manufactured by a casting method such as lost wax or the like, and is fixed to other parts such as the lens frame 2 by brazing. Here, lost wax is a method of making a precise casting by making a model with a wax, filling the mold material around it, heating it, pouring the wax into a mold, and pouring the molten metal here. It is used as a method for producing castings having various shapes. Materials for casting include nickel silver, brass, nickel chromium alloy and the like.

[0003]

When attempting to make a part of a spectacle frame using these alloys,
Brass has a problem in that the required strength cannot be obtained for casting parts of a spectacle frame, and when cast, scratches, pinholes and the like are likely to occur. Nickel-chromium alloys can provide a certain level of strength, but have a problem that the casting temperature is high, so that the flow of molten metal is poor in detail and the mass productivity is poor. On the other hand, beryllium copper alloy (Be 1.6 to 2.0%, Ni + Co + Fe 0.6
% Or less, the balance of Cu) has been widely used as an alloy for components of glass frames by casting. The reason is that the beryllium copper alloy has a good flow of molten metal at the time of casting, is less likely to cause scratches, pinholes, etc., and is subjected to age hardening by heating at a temperature of 300 to 315 ° C. for 1.5 to 2 hours after molding. This is because the strength required as a part for glasses can be obtained.

However, since beryllium copper alloy contains 95% or more of copper as a main component, its surface is easily oxidized during a manufacturing process, and it is very difficult to completely remove an oxide film formed. If plating is performed in this state, plating failure such as plating peeling will occur. Further, the beryllium copper alloy is used after being subjected to age hardening treatment by heating to strengthen the material. However, there is a problem that the beryllium copper alloy is easily deformed as the age hardening treatment proceeds. Furthermore, the range of temperature and time for the age hardening treatment that is optimal for eyeglass parts is narrow, and if it is out of this range, the necessary strength and hardness cannot be obtained, or conversely, the hardness becomes too high and the parts become brittle, and the parts will not be processed in subsequent processing. Breakage or other damage may occur. In addition, when beryllium copper alloy parts are made of other materials such as titanium, nickel silver, monel, etc., and are to be brazed to parts of a glasses frame, for example, a lens frame, the beryllium copper alloy has a large thermal conductivity and an electrical conductivity. On the other hand, titanium, nickel silver, monel, and the like have a low thermal conductivity and a large electric resistance as compared with the beryllium copper alloy, so that there is a problem that it is difficult to braze them. The color tone of the beryllium copper alloy is close to that of copper and reddish. When a part made of a beryllium copper alloy is joined to a part made of a material close to white such as nickel white to form a glasses frame, the difference in color tone between the two parts becomes large. It is more convenient to use a material that is closer to white than a beryllium copper alloy as the eyeglass part.

[0005] In order to solve these problems, the present inventors have proposed to add a silver-white silver having a low melting point to a ternary alloy of copper, nickel and tin (Cu-Ni-Sn alloy) which is a spinodal copper alloy. As a result, we have developed a casting alloy that is age-hardening and suitable for casting and has a color close to white (Japanese Patent Application No. 7-213071). However, this alloy was expensive compared to beryllium copper alloy because it contained silver. The present invention has been made in order to solve the above-mentioned problems of the prior art, and has good castability and the required strength as a spectacle frame, and is an inexpensive alloy for a cast part of a spectacle frame, and a cast using this alloy. The purpose is to obtain a part created by the above method. Another object of the present invention is to obtain an alloy for a part having a complicated shape such as an accessory having a similar composition and a part made of the alloy. Further, the present invention provides a method for manufacturing these eyeglass frame parts or accessory parts.

[0006]

[Means for solving the problems] Yohaku (Cu-Zn-Ni alloy)
Since it has a beautiful silver-white luster, and has good spreadability and corrosion resistance, it is widely used in ornaments such as eyeglass frames. The present invention is based on nickel silver, and by adding manganese and aluminum, an alloy for casting parts of a new eyeglass frame having age hardening properties while maintaining nickel silver properties, and made by casting with this alloy. It is intended to obtain the parts that have been obtained. The alloy for cast parts of the glasses frame of the present invention is, by weight%, zinc 20-42.
%, 5 to 15% of nickel, 3 to 10% of manganese, and 0.2 to 3% of aluminum, and the balance is mainly composed of copper. It is preferable that the alloy for a cast part of the spectacle frame of the present invention further contains 0.5 to 3% of tin by weight. Tin does not promote age hardening, but does improve the hardness of the alloy. The present invention is also directed to a component of a spectacle frame, particularly a hinge component, which is made by casting with the alloy for a cast component and subjected to age hardening treatment. Also,
The present invention is also directed to accessory component alloys and accessory components of similar composition.

[0007] The present invention further provides a method for manufacturing eyeglass frame parts and accessory parts. The method for producing a spectacle frame part or accessory part of the present invention comprises, by weight%, 20 to 42% of zinc, 5 to 15% of nickel, 3 to 10% of manganese, and 0.1 to 3% of aluminum;
Performing a step of preparing a molten metal having a balance of copper and unavoidable impurities, a step of casting the molten metal by a lost wax method, and performing an age hardening treatment at a temperature of 310 ° C. to 410 ° C. for 0.5 to 2 hours. And a step of curing to a Vickers hardness of 220 or more.

[0008] The age hardening treatment, which is a feature of the present invention, has been extensively studied for Al-Cu alloys. In the case of an Al-4% Cu alloy, a solution-treated alloy is quenched to obtain a supersaturated solid solution. When the alloy is kept at an appropriate temperature, age hardening occurs and the process of precipitating the second phase proceeds. The precipitation process is supersaturated solid solution →
GP (1) zone → GP (2) zone → θ'CuAl ₂ → θCuAl
Proceed with ₂ . The GP zone has a thickness number divided by a width of 1 on the lattice plane of Al.
An aggregate of Cu atoms is formed in a range of about 00 °. Although the intermediate phase θ ′ has a different crystal structure, it is still connected to the crystal lattice of the parent phase, and therefore the dimensions of the parent phase and the intermediate phase θ ′ are both slightly changed and the dimensions are matched. The crystal lattice is distorted and the alloy becomes harder.
The state in which the atoms belonging to the crystal lattice of the mother phase and the lattice of the precipitation phase are connected to each other in this manner is called a matching state.

The precipitation process by age hardening of a beryllium copper alloy is a supersaturated solid solution → GP zone → γ ′ intermediate phase → γ equilibrium phase. The GP zone and γ ′ intermediate phase match the parent phase and these harden. Contribute. In this alloy, continuous precipitation proceeds, but at the same time, grain boundary reaction precipitation also progresses, and the strength of the alloy decreases. In order to suppress the progress of grain boundary reaction precipitation, a method of adding a trace element is usually employed, and the addition of Co, Ni, Ti is effective for a beryllium copper alloy. It is considered that the hardening of the alloy of the present invention progresses by the same mechanism as these alloys.

The content of each element in the alloy of the present invention will be described. (1) Zn If the content of zinc is less than 20%, the alloy becomes reddish and a desired white color tone cannot be secured. If the content exceeds 42%, the toughness is reduced and casting defects are likely to occur. Therefore, the content of zinc is set to 20 to 42%. (2) Ni Nickel contributes to the improvement of strength and heat resistance and makes the casting structure fine. If the nickel content exceeds 15%, the ductility (workability) of the alloy deteriorates and the melting point increases, which adversely affects the castability. Material costs also rise. 5%
If the content is less than 5, corrosion resistance deteriorates.
It was determined to be 5%. (3) Mn manganese has the effect of improving the strength of the alloy and whitening its color tone. When the content is less than 3%, the alloy becomes reddish. On the other hand, when the content exceeds 10%, a large amount of slag is generated at the time of melting, so that the solubility is deteriorated and the machinability is also lowered. -10%.

(4) Sn tin is an element that improves the strength and spring properties of the alloy, and is preferably added. If the content of tin is less than 0.5%, the above effect is small, and if the content exceeds 3%, the toughness of the alloy is reduced. Therefore, when tin is added, the content is set to 0.5 to 3%. (5) Al Aluminum is an element necessary for obtaining a desired hardness by age hardening. If the aluminum content is less than 0.2%, it cannot be cured by age hardening. 3
%, The aluminum precipitates in the alloy, so that the toughness is reduced and the plating is hardly adhered. Therefore, the content of aluminum is set to 0.1 to 3%. Further, the content of aluminum is more preferably in the range of 0.2 to 0.8%.

[0012] The melting point of the alloy of the present invention is 900 to 920 ° C, and it can be easily melted and cast at a temperature higher than this by a high frequency melting furnace or the like. The alloy of the present invention is water-cooled after casting, and then hardened by performing age hardening treatment.However, the age hardening conditions are such that the hardness is maximized under certain conditions, and the hardness is lower in an insufficient range and an excessive range. Become. FIG. 3 shows a curve representing the relationship between the temperature and hardness of the age hardening treatment of the alloy of the present invention. As is clear from the figure, the preferred age hardening treatment temperature for obtaining the desired hardness is 310 to 310.
410 ° C. If the age hardening treatment temperature is lower than 310 ° C., the curing is not sufficiently promoted, and if it exceeds 410 ° C., it softens rather. The reason is considered to be that overage softening occurs due to the grain boundary precipitation reaction. Regarding the age hardening treatment time, if the time is less than 0.5 hour, the curing is insufficient, and if the time is longer than 2 hours, it is not preferable from the viewpoint of the growth of precipitates and the economical efficiency. 0.5 to 2 hours is preferred. Therefore, the preferred age hardening condition is 310
C. to 410.degree. C. for 0.5 to 2 hours, more preferably at 350.degree. C. to 380.degree. C. for 50 to 70 minutes.
Optimum conditions are one hour at a temperature of 370 ° C.

The hardness required for the glasses frame is said to be Vickers hardness Hv 220 or more. After the age hardening treatment of the alloy of the present invention in a temperature range of 310 ° C. to 410 ° C., a hardness of Hv 230 to 270 is obtained, and the alloy has a sufficient hardness. Further, even if post-processing is performed as a frame part of a spectacle, a defect such as breakage does not occur, and the lens has a sufficient quality as a frame part.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments and examples of the present invention will be described. (Example 1) Zinc 36.5%, nickel 8.5%, manganese
A copper alloy containing 5.5% and aluminum 0.5%, with the balance being mainly copper, to which 0.1% boron is added as a flux, melted in a high frequency melting furnace, and made by the lost wax method. It was poured into a mold for frame parts and cast. The resulting cast product was water-cooled and then subjected to an age hardening treatment in a furnace at 370 ° C. for 1 hour to harden, thereby obtaining a hinge part 4 of a glasses frame having a shape shown in FIG. The molten metal flow during casting was good, and decorative patterns of 0.5 mm or less were clearly transferred in detail. The hardness of the alloy of Example 1 was Hv 145 before hardening,
It was Hv262 after the age hardening treatment. In addition, this alloy
The hardness after age hardening at 80 ° C for 1.5 hours is Hv 21
The hardness after the age hardening treatment at 420 ° C. for 1.5 hours was Hv 154. It can be seen that if the temperature of the age hardening treatment is low, sufficient hardness cannot be obtained, and if the temperature is too high, no hardening will occur. Example 2 A component of a spectacle frame was prepared in the same manner as in Example 1 except that 0.7% of aluminum was contained and the other components were the same copper alloy as in Example 1. The condition of the age hardening treatment was 300 ° C. for 1.5 hours. The hardness of the alloy of Example 2 was Hv 175 before hardening and Hv 248 after age hardening.

Example 3 Using a copper alloy of Example 1 and an alloy obtained by adding 1.25% of tin, a component of a glasses frame was prepared in the same manner as in Example 1. The condition of the age hardening treatment was 320 ° C. for 2 hours. The hardness of the alloy of Example 3 was Hv170 before hardening and Hv228 after age hardening. (Comparative Example) A beryllium copper alloy (beryllium copper type 2 JIS C1720) to which beryllium 1.9% was added was melted and cast by the lost wax method to produce a spectacle frame part having the same shape as in Example 1 and aging. The cured sample was used as a comparative sample. Parts were also prepared for two types of western white (JIS C7521). However, the age hardening treatment was not performed. Table 1 shows the physical properties of these alloys.

Table 1 Alloys of the present invention Comparative Examples Examples 1 to 3 Be-Cu 2 nickel silver 2 melting point ° C 900 to 920 870 to 980 1060 to 1110 Specific gravity 8.3 8.36 8.8 Softening temperature ° C 480 400 ° C 410

Next, the solubility of the alloys of the above Examples 1 to 3,
Table 2 shows the results of quality tests such as workability such as castability, corrosion resistance, brazing property, color tone, and deformation after age hardening. First, the workability of the alloy of the present invention and the alloy of the comparative example will be compared. The solubility was determined by the melting point of the alloy. Melting points of the two types of nickel silver are as high as 1060 to 1110 ° C, whereas the alloy of the present invention has a melting point of 900 to 920 ° C, which is a suitable temperature for casting. For castability, fluidity,
Observation was made on the degree of occurrence of cavities and the casting surface on the surface of the cast body for comparison. The alloy of the present invention had good fluidity, voids, and casting surface, and thus had good castability. The strength was not measured because it was difficult to measure small parts such as the parts of the glasses frame, and the strength was determined by measuring the Vickers hardness. The Vickers hardness before the hardening treatment in Example 1 was Hv 145, but after the age hardening treatment, it was Hv 262, which was sufficient hardness as a part of a glasses frame.

The deformation due to the age hardening treatment was determined based on whether or not the deformation occurred due to the age hardening treatment.
Compared with the case where the alloy of the present invention was subjected to age hardening treatment of beryllium copper, there was almost no deformation, and it was possible to maintain the dimensional accuracy required for eyeglass parts. The bending workability was determined by bending the part after the age hardening treatment at a radius of R = 0.2 mm by 90 °, observing the bent portion with a 20-fold loupe, and determining whether cracks occurred. The beryllium-copper part of the comparative example is broken by 90 ° bending, whereas the part made of the alloy of the present invention does not have any abnormalities such as bending even when bent by 90 °, and has a toughness enough to withstand post-casting processing. It was found to have The brazing property was determined based on whether or not the glasses frame alloy of the present invention could be brazed well to nickel silver and monel. The glasses frame alloy of the present invention had good brazing properties with these materials, and did not undergo deformation due to brazing. This is because the alloy of the present invention is a component close to nickel white which is widely used as a material for eyeglass frames, and therefore has substantially the same thermal conductivity and electric resistance as nickel white, and has a high softening temperature of 480 ° C.

Next, the quality test results of the alloys of Examples 1 to 3 according to the present invention will be described. The corrosion resistance was determined by an artificial sweat test. Artificial sweat is an artificially prepared aqueous solution of a component similar to sweat, and is prepared by dissolving sodium chloride, sodium sulfide, urea, and the like at a fixed ratio in distilled water. The corrosion resistance was evaluated by visually observing discoloration of the surface after intermittent immersion of the sample in artificial sweat, and judging that there was no discoloration, も の was slightly discolored, and X was discolored. The composition of the artificial sweat and the test conditions are shown below. As a result, as shown in Table 2, discoloration occurred in the Be-Cu of the comparative example, but the alloy according to the present invention produced only the same degree of discoloration as nickel silver, and the corrosion resistance was better than that of Be-Cu. Was. Plating property was determined based on whether palladium-nickel could be plated well. After electrolytic degreasing of the sample in an alkaline degreasing bath, palladium-
Nickel plating, bending test under the same conditions as above, peeling test with cellophane tape,
When the plating did not peel off, it was marked as “○”. Embodiment 1 of the present invention
The alloys Nos. 3 to 3 did not undergo plating peeling and had good plating properties. It is considered that the alloy of the present invention has a small oxide film on the surface. As for the color tone, the degree of whiteness was visually determined. As the alloy for the glasses frame, a color tone closer to white such as nickel-white is preferable to a copper color such as beryllium copper. The alloy of the present invention is close to white since the components are close to white, and is closer to white as compared with beryllium copper.

Table 2 Alloys Examples of the present invention Comparative Examples 1 to 3 Be-Cu type 2 nickel silver type 2 solubility ○ ○ △ castability (fluidity etc.) ○ ○ △ hardness (Hv hardness) ○ (228- 262) ○ (300) × (120) Deformation after age hardening ○ × − Bendability (90 ° bending) ○ × ○ Brazing property ○ △ ○ Corrosion resistance (artificial sweat) △ × △ Plating property ○ △ ○ Color tone (white ○) ○ × ○ ○ Good △ Somewhat bad × Bad Artificial sweat composition: NaCl 9.9 g / l Na ₂ S 0.8 g / l (NH ₃ ) ₂ CO 1.7 g / l C ₁₂ H ₂₂ O ₁₁ 0.2 g / l 28% NH ₃ 0.07 g / l CH ₃ CH (OH) COOH 1.1 g / l Artificial sweat test condition: Immerse in artificial sweat at 37 ° C for 25 minutes → Repeat drying 3 times with warm air at 55 ° C for 25 minutes → Dry with hot air for 30 minutes

According to the embodiment of the present invention, the castability is good, the number of scratches and pinholes is small, and a hardness of 200 or more Vickers hardness required as a component for a glasses frame is obtained by age hardening treatment. Has the same level of corrosion resistance and thermal conductivity as, has good plating properties, has little deformation due to age hardening, and is easy to braze with nickel silver, monel, etc., which are widely used as glasses frame materials. It was possible to obtain an alloy for a component of a spectacle frame suitable and having a color tone close to white. Although the present invention has been described as an example in which the present invention is used for a cast part of a spectacle frame, the alloy of the present invention is not limited to the spectacle frame part, but also includes earrings, rings, necklaces, brooches, bracelets, watches and other women's accessories. It can also be used for parts of men's accessories such as parts, tie pins, cuffs, buckles, watches, etc.

[0022]

According to the present invention, it is possible to obtain an inexpensive cast-part alloy for a spectacle frame, which has good castability and the required strength as a spectacle frame, and a part made of this alloy. Further, it is possible to obtain an alloy for a component having a complicated shape such as an accessory, and an accessory component made of the alloy.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a glasses frame.

FIG. 2 is an enlarged perspective view of a part of the glasses frame of FIG. 1;

FIG. 3 shows an age hardening curve of an alloy for cast frames of the present invention.

[Explanation of symbols]

 1 glasses frame 2 frame 3 vine 4 hinge parts 5 jewel

Claims (5)

[Claims] 1% by weight of zinc 20-42%, nickel 5-15%, manganese 3-10% and aluminum 0.1%.
An alloy for a casting part of an eyeglass frame or accessory, characterized in that the alloy contains 1 to 3% and the balance consists of copper and unavoidable impurities. 2. The composition contains 20 to 42% by weight of zinc, 5 to 15% of nickel, 3 to 10% of manganese, 0.5 to 3% of tin, and 0.1 to 3% of aluminum, with the balance being copper. And alloys for casting parts of eyeglass frames or accessories, characterized by comprising unavoidable impurities. 3. 20% to 42% by weight of zinc, 5% to 15% of nickel, 3% to 10% of manganese and 0.1% by weight of aluminum.
Parts or accessory parts of a glasses frame characterized by being produced by casting with a casting alloy containing 1 to 3% and the balance being copper and unavoidable impurities, and hardened to a Vickers hardness of 220 or more by age hardening treatment. . 4. The composition contains 20 to 42% by weight of zinc, 5 to 15% of nickel, 3 to 10% of manganese, 0.5 to 3% of tin, and 0.1 to 3% of aluminum, with the balance being copper. A part or accessory part of a spectacle frame, which is made by casting with a casting alloy comprising unavoidable impurities and hardened to a Vickers hardness of 220 or more by age hardening treatment. 5. A method for producing a part of a spectacle frame or an accessory part, comprising, by weight, 20 to 42% of zinc, 5 to 15% of nickel, 3 to 10% of manganese, and 0.1 to 3% of aluminum. Preparing a melt containing copper and inevitable impurities, casting using the melt by a lost wax method, and aging at a temperature of 310 ° C. to 410 ° C. for 0.5 to 2 hours. A step of performing a curing treatment and curing to a Vickers hardness of 220 or more,
A manufacturing method comprising: