JPH02153034A - Alloy for key - Google Patents

Abstract

PURPOSE:To manufacture an alloy material by which a key having good color tone and excellent visual quality and visual beauty is manufactured by incorporating specific ratios of Ni, Zn and Mn into copper and preparing an alloy in which the structure of different concn. at the time of casting remains. CONSTITUTION:A copper alloy contg., by weight, 3 to 8% Ni, 7 to 15% Zn, 0.01 to 0.6% Mn and the balance copper with inevitable impurities and in which the structure of different concn. at the time of casting, that is called cast structure, remains is prepd. The copper alloy has excellent strength and machinability; when a key is manufactured by using the copper alloy, the one having good color tone and having excellent visual quality and visual beauty can be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) This invention relates to a material for keys used in automobiles and the like.

[Conventional technology]

Conventionally, keys for automobiles and the like have been mainly made of brass-based alloys and nickel-plated. In addition, high-grade products are made from a nickel-white alloy.

(Problems to be Solved by the Invention) By the way, materials for keys are generally required to have strength and machinability, and are also required to have a color tone that gives the key as a product excellent quality and beauty. It is being

From this perspective, conventional brass-based alloys have a certain level of strength and machinability, and are relatively inexpensive. However, the color tone of the key is not the color of the alloy itself, but the color of the nickel plating applied to it, which is silvery white or yellowish gray, giving the key as a product particularly excellent quality and beauty. It wasn't something. Furthermore, when the nickel-plated keys are used repeatedly, the plating wears out or peels off, resulting in a significant loss of quality and beauty.

On the other hand, some alloys of nickel white yarn have value as imitation silver, have excellent cutting workability, and have few problems, but have the drawback of being expensive.

Also, the same nickel silver alloys include copper and nickel.

In addition to zinc, manganese, and lead, there are also products that contain iron, which gives the alloy a brownish color.
It is not preferred as a key material because it impairs the color tone of the key.

This invention was made to solve these conventional problems, and provides an inexpensive key alloy that has excellent strength and machinability, has a good color tone, has excellent external quality and beauty, and is inexpensive. The purpose is to provide.

[Means to solve the problem]

The key alloy provided by this invention is 3 to 8% by weight of nickel.
, zinc 7-15% by weight, manganese 0.01-0.6!1
11%, and the remainder consists of copper and unavoidable impurities, and the so-called cast structure, which is a structure with a different concentration during casting, remains. In terms of composition, the content of nickel and zinc in the conventional alloy of nickel silver yarn is reduced.

The color tone of the alloy changes depending on the amount of nickel and zinc added; if there is a lot of nickel, the alloy will turn white, and if there is a lot of zinc, it will turn yellow. Therefore, the range of nickel and zinc components is such that the color tones produced by each component harmonize well to produce an alloy with decorative value, which has a bright reddish-yellow to pink color, that is, an alloy with excellent external quality and beauty. The scope of

In other words, the reason why the nickel content is limited to the above range is that if the nickel content is less than 3% by weight, the reddish tint of copper becomes strong, and if it exceeds 8% by weight, the whitening due to nickel progresses and at the same time the price of nickel increases. This is because the alloy is expensive because of the high

Zinc is necessary to improve strength due to its synergistic effect with nickel, and has the advantage of being inexpensive. The reason why the content is limited to the above range is that if the zinc content is less than 7% by weight, no improvement in strength can be expected, and if it exceeds 15% by weight, the yellowing of the alloy will become stronger and the appearance value will be impaired. .

Manganese was added as a deoxidizing agent to suppress casting defects. The reason why the minimum required amount was set at 0.01% by weight is because if it is less than stiffness, it cannot be expected to function as a deoxidizing agent, and the reason why the upper limit was set at 0.6% by weight is that if it exceeds this This is because castability deteriorates.

The material for the key needs to have good machinability, but
Copper alloys having a general recrystallized structure have poor machinability. For this reason, products improved by adding lead are also used. However, those containing lead have the disadvantage of deteriorating machinability.

The reason for leaving the cast structure is to not create a recrystallized structure that deteriorates machinability, and to utilize the characteristics of the cast product, which has excellent machinability, as it is.

[Effect]

In this invention, by specifying the component ranges of nickel and zinc, we were able to harmonize the color tones produced by each component, resulting in an alloy with a pale reddish-yellow to pale pink color, that is, an alloy with excellent external quality and beauty. It is possible to obtain an alloy with

Also, the casting structure was left to remain.

The resulting alloy retains the properties of a cast product, and its machinability is improved.

Furthermore, the alloy of the present invention is relatively inexpensive due to the reduced content of expensive nickel. Furthermore, since a part of the zinc in the brass alloy is replaced with nickel, there are no practical problems in terms of mechanical properties, especially tensile strength.

(Examples 1 to 3) Examples 1 to 3 of this invention will be described below.

For each Example, b, and sample, the ingredients shown in Table 1 were continuously cast into a plate-shaped ingot with a thickness of 15 mm, and this was finished into a plate-like ingot with a thickness of 2 mm only by cold working without heat treatment. The characteristics of each sample were evaluated and were as shown in Table 1.

Comparative Examples 1 to 4 are listed for comparison. Comparative Example 1.2 is a brass alloy, and Comparative Example 3.4 is a nickel silver yarn alloy.

As is clear from Table 1, all of the alloys in the examples have excellent 1' JIJ workability, and their strength is also superior to brass-based ones and comparable to nickel-silver-based ones, making them suitable for practical use as key materials. It is at a level that can be provided.

The color tone is pale red-yellow or pale pink, and it can be seen that when this alloy is used as a key material, it is sufficient to enhance its external quality and beauty.

The alloys of the above embodiments can be used as they are for keys without being plated unlike conventional brass alloys. Furthermore, even though it is made of the same alloy of nickel white yarn, it uses only a small amount of nickel, so it can be said to be a relatively inexpensive key material in terms of cost.

(Effects of the Invention) As explained above, according to the present invention, the composition is based on a nickel silver-based alloy with a reduced content of nickel and zinc, and the range of both components is a pale red color in the alloy. We specified a range that could impart a yellow or pink color, and the structure was designed to leave the cast structure, so it has excellent strength and machinability, has a good color tone, has excellent external quality and beauty, and is inexpensive. Key alloys can be obtained.

Claims (1)

[Claims] 3-8% by weight of nickel, 7-15% by weight of zinc, 0.01-0.6% by weight of manganese, the balance being copper and unavoidable impurities, and a structure with different concentrations during casting (so-called cast structure) remains. Alloy for keys.