JPH0433859B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Fields> The disclosed technology develops the composition of a palladium alloy with a stainless steel color that can be used not only as a watch frame but also as a material for jewelry such as watch bands, rings, and necklaces. Belongs to the technical field. <Prior Art> As is well known to those skilled in the art, gold alloys, silver alloys, and platinum alloys are used as precious metal alloys for conventional white watch frames and watch bands, as well as jewelry such as rings and nets. Stainless steel alloys are examples of base metal alloys. <Problems to be Solved by the Invention> All of these metal materials have overlapping advantages and disadvantages, as described below. In other words, the former precious metal alloys, such as gold alloys and platinum alloys, have advantages in terms of functionality and ornamental value when used as watch materials, but on the other hand, they have the disadvantage of high costs. In addition, the price is greatly affected by fluctuations in metal costs, and there is also the disadvantage that it is not new as a watch material. Furthermore, although silver alloys have the advantage of having a unique warm silvery white color tone, they have practical disadvantages of insufficient strength and poor sulfidation resistance. Regarding the latter stainless steel alloy, which is based on base metals, although it has the advantage of being highly practical as a watch material and having a unique white color that cannot be reproduced with precious metals,
The problem is that it has little decorative value. <Purpose of the invention> The purpose of the invention of this application is to solve the technical problem of the alloys of accessories such as watch frames based on the above-mentioned prior art, which have contradictory advantages and disadvantages. Although it takes advantage of good alloy properties, it has a stainless steel color tone that is difficult to reproduce with precious metals, and also has mechanical strength and workability that allow it to fully function as a structural material for watches, etc. It is an object of the present invention to provide an excellent palladium alloy for jewelry, which has sufficient corrosion resistance during use and is useful for metal processing technology applications in the accessory manufacturing industry. <Means/effects for solving the problem> In order to solve the above-mentioned problem, the structure of the invention of this application, which is based on the scope of the above-mentioned patent claims, is to solve the above-mentioned problem. Palladium alloys for jewelry used in jewelry contain 50-95% palladium and 5-50% chrome.
%, and further add elements of 1-10% tungsten, 1-10% molybdenum, 1-5% antimony, and 1-10% silver as necessary to the base alloy. Technical measures have been taken to make it possible to adjust the color tone, and to have high strength, corrosion resistance, and good workability. <Background of the Invention> Next, to discuss the qualitative and quantitative background of the invention of this application, palladium, which is the main component, has the property of being resistant to chemical changes by acids and oxidized in the air. In order to function as an element contributing to such stabilization, the weight ratio in the alloy needs to be 50% or more, while if it exceeds 95%, for example, it is necessary for a watch case. It is no longer strong enough. Therefore, the optimum weight is preferably in the range of 50 to 95%. Next, regarding chromium, it is metallurgically composed of a solid solution between Pd and Pd ₂ Cr ₃ compounds as a palladium-chromium alloy, and its mechanical strength is
It is maximum at 60Pd40Cr. Basically, it is possible to cancel out the dull white color tone peculiar to palladium and make it closer to the so-called stainless steel color.It is ineffective if the weight ratio is less than 5%, and if it exceeds 50%, it becomes brittle. The rate was set at 5-50% because it was experimentally confirmed that this would make it difficult to punch out the material itself and even the watch frame. In addition, tungsten can increase the strength of the material alloy and improve the grindability during processing necessary for making watch frame materials, etc. If the weight ratio is less than 1%, it will not be effective, and if the weight ratio is less than 10%
It has been found that when the value exceeds 100%, the workability during pressing is poor. Therefore, empirically, the weight ratio is 1
~10%. As for molybdenum, it acts to control the color tone of products and is important as a function that contributes to aesthetics, and furthermore, it is said that it can impart excellent properties such as deoxidizing effect when dissolving materials. Confirmed experimentally. It has been found that their maximum effective weight blending ratio is in the range of 1 to 10%. Next, antimony is useful for lowering the melting point.The base palladium-chromium alloy has a melting point of over 1300℃, but adding antimony makes it possible to relatively lower the liquidus point, which allows it to melt during material production. It is known that it improves castability, and if it is less than 1%, it will not be effective, and if it exceeds 5%, it will cause the material to become brittle, so it is set in the range of 1 to 5%. Finally, silver helps to improve the spreadability of the material, and in addition, it has a color tone control effect, and its optimum range is less than 1%, which has no effect, and if it exceeds 10%, the color tone changes. The range is 1 to 10%. Next, embodiments of the invention of this application will be described as follows. First, samples of alloys according to embodiments of the invention of this application and alloys of known examples are shown in the table below. The alloy of each sample was made by melting each material in a well-known high-frequency heating melting furnace at a melting temperature of 1600℃ for 30 minutes, casting it into a shape of T10 x W50 x L100mm, and then rolling it into the specified shape with cold rolling rolls. This made it possible to roll the material into

[Table] Next, the processed materials of each sample obtained as described above were used as materials with a processing rate of 50%, and the necessary number of sheets were cut, and hardness tests, tensile tests, discoloration tests due to artificial sweat, and specular color difference measurements were performed. . The test results are shown in the table.

【table】

[Table] In addition, hardness test: Load using a Micro Bitskers hardness meter
Measured under the conditions of 200g and 30 seconds load time. Tensile strength measurement test: Measured using a Tensilon tensile tester at a tensile speed of 100 mm/min on a tensile test piece (JIS No. 6 test piece). Discoloration test: The degree of discoloration was investigated by immersing it in artificial sweat with the following mixing ratio for 24 hours in a constant temperature box at 50±2℃. Chloride 0.648-0.987% Sulfide 0.006-0.0025% Urea 0.086-0.173% Ammonia 0.010-0.018% Sutucarose 0.006-0.022% Lactic acid 0.034-0.107% Distilled water Residue Color difference measurement: Specular reflection light sticks like metal color color Measure the color difference between stainless steel and stainless steel using a specular reflection colorimeter that measures the color of objects. L (lightness) 116 (Y/Yn) ^1/3 -16 Y/Yn>0.008856 a (chromaticity) 500 [(X/Xn) ^1/3 - (Y/Yn) 1/3] b (chromaticity) 200 [(Y/Yn) ^1/3 - (Z/Zn) 1/3] ΔEab Overall color tone difference As can be seen from the above test data, the palladium alloy of the embodiment of the invention of this application has a sufficient It can be seen that it has hardness and mechanical strength, has good corrosion resistance, and has a significantly better color tone than stainless steel. <Effects of the Invention> As described above, according to the invention of this application, palladium alloy, which is used as a material for jewelry such as watch frames, watch bands, rings, and net necklaces, has all the advantages of precious metals, but has the hardness and mechanical properties. It also has good physical strength, so the product retains its shape well and reliably fulfills its function as an accessory, and has excellent corrosion resistance, so it maintains its functional properties as an accessory over time. The excellent effect of being able to do this is achieved. In addition, the color tone of stainless steel is satisfactory, and in addition, the price for jewelry is not as high as that of gold alloys and platinum alloys, and it is less affected by price fluctuations, allowing a stable supply to be maintained. This effect is produced. It has these functional properties as well as corrosion resistance, has good color tone adjustment function, and can be made at a stable price, making it a stable product not only for manufacturing and supplying jewelry, but also for stable use. This has the excellent effect of gaining trust.

Claims (1)

[Claims] 1. Palladium 50-95% and chromium 5% by weight
~50% palladium alloy for jewelry, characterized by good functional properties, corrosion resistance, and color adjustment. 2 Palladium 50-95% and chromium 5 by weight
1. A palladium alloy for jewelry, characterized in that silver is added in a weight ratio of 1 to 10% to a base alloy consisting of ~50% to promote and improve the properties of the base alloy. 3 Palladium 50-95% and chromium 5 by weight
~50% base alloy with 1~10% tungsten
A palladium alloy for jewelry, characterized in that the palladium alloy is added at a weight ratio of 50% to promote and improve the properties of the base alloy. 4 Palladium 50-95% and chromium 5 by weight
~50% base alloy with 1~10% tungsten
% and molybdenum in a weight ratio of 1 to 10% to promote and improve the properties of the base alloy. 5 Palladium 50-95% and chromium 5 by weight
~50% base alloy with 1~10% tungsten
% and antimony in a weight ratio of 1 to 5% to promote and improve the properties of the base alloy.