JPH0427286B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to constant electrical resistance alloys. In recent years, robots and automation technologies have been widely adopted in factories and other workplaces, contributing to eliminating dangerous work and improving productivity. It can be said that the performance of these technical systems is determined by the performance of the sensor that detects the measurement data to the microprocessor interface. However, there are few good places to work with sensors, and the conditions are often extremely harsh and dangerous. Especially the steel industry,
For various measurements such as temperature, pressure, or displacement in the chemical industry, nuclear power-related work, space-related industry, etc., it has cleared environmental resistance, is stable for long-term use, has excellent maintainability, and is safe. There is a growing demand for excellent sensors with good performance. For example, in the case of a continuous casting process that allows for the integrated production of high-yield, high-quality steel, it is possible to measure the amount of raw material powder in the blast furnace, tundish, or mold, the level of the molten steel, and the thickness, width, and rolling speed of the slab. The sensors used are exposed to high temperatures of 800 to 1000 degrees Celsius and steam, so not only must they withstand these harsh environments, but their characteristics must remain stable over long periods of time. Conventionally, methods using ionizing radiation such as gamma rays and X-rays have often been adopted for the above-mentioned measurements, but these methods have many drawbacks, such as the large size of the equipment and the danger to the human body. Therefore, in recent years, the use of eddy current displacement meters (hereinafter simply referred to as sensors), which are small and easy to handle, has come to be considered. Since the performance of a sensor is determined by the sensor coil material, its electrical characteristics and stability are particularly important. For example, in the case of the continuous casting process mentioned above,
Since the sensor coil material operates continuously at high temperatures of 800 to 1000℃ for several months to several years, the conditions required for the sensor coil material are that the temperature coefficient of electrical resistance remains unchanged for a long time at 100ppm/℃ or less, and it also has corrosion resistance. It is also important that the wire has good oxidation resistance and processing formability, as well as excellent thermal stress fracture resistance, which is closely related to wire breakage. Since the characteristics of the sensor require calibration measurements not only in the high temperature range but also in the normal temperature range, the electrical characteristics must be as excellent in the normal temperature range as in the high temperature range. Since there is currently no sensor coil material that meets these conditions, there is a strong demand for its development from related industries. Conventionally, as this type of sensor coil material, palladium-silver alloy (Japanese Patent Laid-open Publication No.
No. 55-122839) and palladium-iron alloy (Japanese Patent Application No. 58-113332), but each alloy system has its advantages and disadvantages as described below. In other words, the former alloy has good corrosion resistance, oxidation resistance, and workability at high temperatures, and also has -50 to 600
It has an extremely small temperature coefficient of electrical resistance of less than ±20 ppm/°C over a wide temperature range of °C, but at temperatures below -50°C and above 600°C, the temperature coefficient of electrical resistance is more than ±100 ppm/°C. Not only does it show a very large value, but if a sensor using this material is operated continuously at high temperatures for a long period of time, the crystal grains of the material will become coarse and the characteristics will deteriorate, and in the worst case, it will cause problems due to disconnection. This often resulted in serious damage to production control. In the case of the latter alloy, the temperature coefficient of electrical resistance is ±
Although it has the characteristics of being small (less than 100 ppm/°C) and having extremely stable characteristics even when used continuously at high temperatures for long periods of time, it is unstable due to large changes in electrical resistance at temperatures below the regular-irregular transformation point. Not only that, but it also has many drawbacks and restrictions, such as extremely poor oxidation resistance at high temperatures and poor workability, requiring a high degree of ingenuity in its manufacture and use. Therefore, in order to meet the urgent needs of related industries, the present inventors immediately conducted a comparative study on the above-mentioned palladium-silver alloy and palladium-iron alloy, and found that they are easy to handle in mass production.
We also attempted to improve palladium-silver alloys that have excellent processability and moldability. In other words, the present inventors found that the constant electrical resistance property of palladium-silver alloys is such that when the scattering of conduction electrons due to lattice vibration and the short-range regularity of the crystal are balanced, the scattering of electrons becomes constant and changes in electrical resistance are reduced. However, at temperatures below -50°C and above 600°C, the balance between these two factors is disrupted, leading to increased scattering of electrons and a loss of constant electrical resistance properties. Incidentally, FIG. 1 shows the temperature coefficient of electrical resistance with respect to the amount of Ag in a palladium-silver alloy. Here, the curves and are 0 to 400℃ and −150℃, respectively.
It is the average temperature coefficient of electrical resistance between temperatures of ~1000°C and -200 to 1200°C. In Figure 1, when the average temperature coefficient of electrical resistance is 100 ppm/℃ or less, it is between point c (Ag33.2%) and point d (46.7%Ag) on the curve and point a (Ag36.0%) on the curve.
It is obtained in the composition range between ~ point b (Ag45.5%),
In the curve, it is extremely large at +100 ppm/℃ or more over all compositions. From the above explanation, −150 to 1000℃
The composition range in which the average temperature coefficient of electrical resistance in a wide temperature range is 100 ppm/℃ or less is between points c and a and between points b and d on the curve.
Ag36.0 (point a) to 45.5 (point b) excluding the composition between points
Limited between %. In addition, the sensor coil disconnection phenomenon occurs when the processed material is recrystallized by continuous heating for a long period of time, and as the heating time increases, the crystal grains grow coarser, causing expansion and contraction due to repeated heating and cooling. It was predicted that thermal stress fracture would occur in addition to external factors, and that the wire would eventually break. That is, as a solution to improving the thermal stress fracture resistance, which is closely related to the high-temperature stability of the sensor, it is first necessary to increase the recrystallization temperature to suppress crystal growth and to reduce the crystal grain size as much as possible. Next, it is also important to set the upper limits of the sensor's operating temperature and service life low. Regarding the former, it is possible to add multiple elements in order to refine the alloy by crystallization. The latter is deeply involved in the manufacturing method of the alloy and sensor, and it is necessary to adopt the optimal processing method and heat treatment method in conjunction with constant electrical resistance characteristics. Here, the thermal stress fracture resistance can be evaluated based on the recrystallization temperature of the alloy, the average crystal grain size, and the stability of impedance after forming the alloy material into a sensor coil. In other words, it can be said that the higher the recrystallization temperature, the smaller the average crystal grain size, and the smaller the change in impedance over time, the better the high temperature stability and thermal stress fracture resistance of the sensor. The present inventors conducted many experiments based on the above facts in order to solve the above problems and obtain a constant electrical resistance alloy that is stable even at high temperatures.
It has been found that addition of elements from groups A to B of the periodic table to a 36.0 to 45.5% silver alloy is extremely effective and effective in improving the average temperature coefficient of electrical resistance and thermal stress fracture resistance at high temperatures. The purpose of the present invention is to solve the above-mentioned problems and -
The present invention aims to provide a constant electrical resistance alloy that shows extremely little change in electrical resistance over a wide temperature range of 150 to 1000°C, has excellent heat stress fracture resistance, and is easy to process and form, and a sensor that has constant electrical resistance characteristics. . The alloys of the present invention are listed below by composition. 1 Iridium 7 as the first choice component by weight
% or less, platinum 5% or less, copper 7% or less, and gold 9
Total of 1 type or 2 or more types below 0.1-10
% and rhodium 5% or less as a second selection component,
Osmium 5% or less, Hafnium 1% or less, Indium 3% or less, Iron 2% or less, Cobalt 2%
The following: Nickel 2% or less, Niobium 1% or less, Tantalum 2% or less, Chromium 1.5% or less, Molybdenum 1.5% or less, Tungsten 0.2% or less, Titanium 1% or less, Yttrium 1% or less, Boron 0.5%.
It consists of 1% or less of rare earth elements, 0.5% or less of carbon, a total of 0.01 to 10% or less, 40.2 to 43% silver, and the balance palladium, and is electrically conductive in the temperature range of -150 to 1000℃. A constant electrical resistance alloy characterized by having constant electrical resistance characteristics with an average temperature coefficient of resistance of 100 ppm/℃ or less and thermal stress fracture resistance. 2 Iridium 7 as the first choice component by weight
% or less, platinum 5% or less, copper 7% or less, and gold 9
Total of 1 type or 2 or more types below 0.1-10
%, and manganese 2% or less as a second selection component,
Rhenium 2% or less, thallium 2% or less, gallium 1.5% or less, aluminum 2% or less, vanadium 2% or less, silicon 1.5% or less, tin 1.5% or less, antimony 1% or less, bismuth 1% or less,
Zinc 1% or less, cadmium 1% or less, total of 0.01 to 10% or less, and silver 40.2
~43%, balance palladium, -150~
A constant electrical resistance alloy characterized by having constant electrical resistance characteristics and thermal stress fracture resistance with an average temperature coefficient of electrical resistance of 100 ppm/°C or less in a temperature range of 1000°C. In addition, after forming a wire or plate material made of the alloy of the present invention into a desired shape such as a spiral or toroidal shape, if necessary, it is subjected to a curling treatment, and then the wire rod or plate material made of the alloy of the present invention is fixed to a room temperature or heat resistant insulator or insulated. It is made into a sensor by a method such as implanting it in the body, and if necessary, it is further heated at 200 to 500℃ for several hours in a non-oxidizing atmosphere or under vacuum to solidify, and then heated at 500 to 1200℃ for 2 seconds or more. A method of imparting constant electrical resistance characteristics by heating for less than 1 hour, or applying a normal temperature or heat-resistant insulator to the surface of a wire or plate made of the alloy of the present invention, coating it by electrodeposition, etc., and then forming a desired shape such as a spiral or toroidal material. After molding them into the shape, they are fixed as they are to a room-temperature or heat-resistant insulator, or embedded in an insulator to form a sensor.If necessary, they are further heated in a non-oxidizing atmosphere or under vacuum for 200 m A method in which the alloy is heated at ~500℃ for several hours to solidify, and then heated at 500 to 1200℃ for 2 seconds or more and 100 hours or less to provide constant electrical resistance characteristics, or alternatively, the alloy of the present invention is used as a room temperature or heat-resistant insulator. After depositing it as a thin film on the surface by an appropriate method such as electrodeposition or sputtering, etching, punching or trimming it into the desired shape, fixing it to an insulator or loading it into an insulator case to use it as a sensor,
If necessary, this is further heated at 200 to 500°C for several hours in a non-oxidizing atmosphere or in a vacuum to solidify it, and then heated at 500 to 1200°C for 2 seconds to 100 hours to obtain constant electrical resistance properties. A sensor can be manufactured by a method of making a sensor. In the above explanation, to explain the meaning of the term constant electric resistance characteristic, the electric resistance of ordinary metal alloys changes greatly with temperature changes, but in the case of the alloy of the present invention, the electric resistance changes extremely in a specific temperature range. The name refers to the property that the temperature coefficient of electrical resistance is small or zero, in other words, the temperature coefficient of electrical resistance is extremely small or zero. As an example, manganin, which has been widely used as a conventional precision resistance material, has a constant electric resistance only near room temperature. Hereinafter, the present invention will be explained in detail with reference to the drawings. Figures 2, 3, 4, and 5 show the amounts of Ir, Pt, Cu, and Au added to the average temperature coefficient of electrical resistance of palladium-silver alloys between -150 and 1000°C, respectively. shows the effect of Figure 6 also shows the average temperature coefficient of electrical resistance between -150 and 1000℃ of Pd-40%Ag alloy with Ir, Pt, Cu or Au added.
The relationship with the amount of Au added is shown. As is clear from these Figures 2 to 6, the amounts of Ir, Pt, Cu, or Au each having an average temperature coefficient of electrical resistance of 100 ppm/℃ or less between -150 and 1000℃ are 7. % or less, 5% or less, 7% or less, or 9% or less. In addition, Figures 2 to 6
In the figure, Pd-Ag-Ir system, Pd-Ag-Pt system, Pd-Ag
- Only the average temperature coefficient of electrical resistance of Cu-based and Pd-Ag-Au based ternary alloys is shown, but multi-component alloys that combine these ternary systems or further include group A to Va group elements as subcomponents. As listed in Table 3 below, it is obvious that the alloys added as 3D alloys have an average temperature coefficient of electrical resistance of 100ppm/℃ or less, as in the case of the four types of ternary alloys mentioned above. be. Next, the alloy of the present invention will be explained in detail. First, to produce the alloy of the present invention, alloy materials having the above-mentioned composition are blended, melted in a non-oxidizing atmosphere or in vacuum using a suitable melting furnace, and sufficiently stirred to obtain a structurally uniform molten alloy. . Next, the molten alloy is cast into iron molds of appropriate shape and size to obtain a sound ingot, and scale, scratches, etc. on the surface of the ingot are removed by grinding, and the ingot is then subjected to various hot working processes through the casting process. Then, it is formed into a desired shape, such as a round bar, a thin wire, or a thin plate, by cold working, such as swaging, wire drawing, rolling, or dipping. Next, these shapes are heated at 200 to 1200°C for 2 seconds or more and 100 hours or less in a non-oxidizing atmosphere or vacuum, so that the temperature coefficient of electrical resistance becomes 100 ppm/°C in the temperature range of -150 to 1000°C. It becomes possible to have the following constant electric resistance characteristics and excellent thermal stress fracture resistance. When the alloy of the present invention is applied to heating elements, sensors, etc., it is usually formed into a coil shape and used, so the constant electrical resistance characteristics of the alloy of the present invention can be fully exhibited by any of the methods described below. Appropriate electrical and thermal insulation shall be provided. 1. After fixing the wire or plate of the alloy of the present invention by directly wrapping it around a room-temperature insulator such as mica or a heat-resistant insulator such as ceramic or by sandwiching it between insulators, place it in a non-oxidizing atmosphere if necessary. In order to evaporate harmful gases and organic substances in the insulator, the inside is heated at 200-500℃ for several hours in a vacuum, and then further heated at 500-1200℃ for 2 seconds or more at 100℃.
Heat for no more than an hour. 2 A wire rod or plate material of the alloy of the present invention is formed into a spiral or toroidal shape in a non-oxidizing atmosphere or in a vacuum.
After being heated at 500-1200℃ for 5 seconds or more and 100 hours or less for curling treatment, it is immersed in a solution made of room-temperature insulators such as water glass or heat-resistant insulators such as ceramic paste at 200-500℃. After heating for several hours to solidify, it is loaded into an insulating case and sealed, and if necessary, further heated at 500 to 1200°C for 2 seconds or more and 100 hours or less in a non-oxidizing atmosphere or in a vacuum. 3 The surface of the wire or plate material of the alloy of the present invention is coated or coated with a room temperature insulator such as formal, or a heat resistant insulator such as polyimide resin or magnesia is deposited by an appropriate method such as electrodeposition or sputtering. After that, the wire is formed into a spiral or toroidal shape.
Heat at 200 to 500℃ for several hours to evaporate harmful gases and organic substances, load it into an insulating case and seal it, and if necessary, heat at 500 to 1200℃ for 2 seconds in a non-oxidizing atmosphere or in vacuum. Heat for more than 100 hours. 4 After the composite of the present invention is attached to the outer surface of an insulating material such as glass or ceramic by an appropriate method such as electrodeposition or sputtering, it is etched, punched or trimmed into a desired shape, and if necessary, fixed to an insulating material or Installed inside an insulating case. After that, homogenization treatment is performed by heating at 200-500℃ for several hours, and if necessary, further heating at 500-1200℃ in a non-oxidizing atmosphere or in vacuum.
Heat for more than 2 seconds and less than 100 hours. It has been revealed that the properties of the product completed through the above steps are exactly the same as those of the alloy of the present invention, and that it can sufficiently exhibit constant electrical resistance properties and thermal stress fracture resistance. Next, the method for manufacturing the alloy and sensor of the present invention will be specifically described with reference to Examples. Example 1 Alloy number PAM-115 (composition Pd=54.85%, Ag=
41.5%, Pt=3.0%, Rh=0.5%, Os=0.1%,
Hf=0.05%) Alloy and sensor manufacturing The raw materials are Pd, Ag and Pt with a purity of 99.9%,
Rh, Os, and Hf with a purity of 99.5% or higher were used. The sample was manufactured by putting a total weight of 1 kg into a high-frequency vacuum melting furnace, degassing it at about 900°C, and then melting it by injecting a small amount of argon gas as an inert gas. 25 melted alloys
A sound ingot was produced by casting into a mm square mold. Next, the surface of the ingot was ground with a milling machine to remove any flaws, and then hot forged and hot formed into rolls with a diameter of 10 mm.
I made it into a round bar. After that, cold processing such as swaging and drawing is performed to make the wire into a fine wire with a wire diameter of 0.5 mm, and then a precision cold rolling machine is used to make the wire into a thin wire with a thickness of 0.28 mm and a thickness of 0.22 mm.
It was made into a ribbon-like thin plate of mm. Among these, a ribbon-shaped thin plate with a thickness of 0.28 mm was used as the alloy sample for electrical resistance measurement, and the measurement was carried out in a vacuum at a temperature range of -160 to 1100°C. In addition, after stacking these two types of thin plates and winding them 20 to 50 times in a toroidal shape,
It was heated for a minute to give it a curl. Then thickness 0.22mm
Remove the ribbon-like coil and reduce the remaining thickness to 0.28mm.
The toroidal sensor coil was immersed in ceramic paste, loaded into a ceramic case, heated at 200°C for 1 hour, 400°C for 30 minutes, and then heated at 1000°C.
Baked for 30 minutes. Next, the impedance change rate of this sensor Δη/η0×100=ηT−η0/η0×100 (%) was measured using the bridge circuit method. The measurement frequency is
It was 1KHz. Here, η0 and ηT are the impedances of the sensor coil at the start of measurement and after time T, respectively. The wire rod sample and comparative alloy PA-4 (composition Pd=58%,
Figure 7 shows the temperature vs. electrical resistance curve of Ag=42%). Also, the average temperature coefficient of electrical resistance 1/R・ΔR/ΔT obtained from this curve and the sensor performance when a sensor using the wire of the invention alloy PAM-1 is used continuously for a long period of time at a high temperature of 800°C or higher. , the rate of change in impedance is as shown in Table 1. Incidentally, the alloy PAM-115 of the present invention is characterized by a very small value of Δη/η0×100, as shown in Table 1.

[Table] Example 2 Alloy number PAM-214 (composition Pd=46.2%, Ag=
40.5%, Ir=3.0%, Pt=1.5%, Cu=5.0%, Si
=0.8%, Sn=0.5%, Sb=0.05%, Bi=0.01%)
Manufacture of alloy and sensor The raw materials are Pd, Ag, and 99.9% pure Pd, the same as in Example 1.
Ir, Pt and Cu, and Si, Sn, with a purity of 99.5% or more
Sb and Bi were used. The manufacturing method and experimental method are exactly the same as in Example 1. Figures 8 and 2 about the electrical characteristics and performance of the alloy sample and sensor.
As shown in the table, the results are similar to those of Example 1.

[Table] Example 3 Alloy number PAM-112 (composition Pd=53.70%, Ag=
40.2%, Ir = 5.0%, Ni = 1.0%, Ti = 0.1%) Production of alloy and sensor The raw materials were Pd, Ag and Ir with a purity of 99.9% as in Example 1, and Ni and Ti with a purity of 99.5% or more. Using. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical characteristics and performance of the alloy sample and sensor are shown in Table 3 and are similar to the results of Example 1.

[Table] Example 4 Alloy number PAM-221 (composition Pd=47.24%, Ag=
42.0%, Au=9.0%, Fe=1.5%, W=0.2%,
Production of alloy and sensor (Mo = 0.05%, C = 0.01%) The raw materials are Pd, Ag, with the same 99.9% purity as in Example 1.
Ir and Au, Fe, W and more than 99.5% purity
Mo and C were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 4 and are similar to the results of Example 1.

[Table] Example 5 Alloy number PAM-205 (composition Pd=50.82%, Ag=
40.5%, Pt=2.5%, Cu=1.1%, Au=5.0%,
Manufacture of alloy and sensor (Mn=0.05%, Re=0.02%, Gd=0.01%) The raw materials are 99.9% pure Pd, Ag, the same as in Example 1.
Pt and Au, and Mn, Re and Gd with a purity of 99.5% or higher were used. The manufacturing method and experimental method are as in Example 1.
It is exactly the same. The electrical properties and performance of the alloy sample and sensor are shown in Table 5 and are similar to the results of Example 1.

【table】

[Table] Example 6 Alloy number PAM-211 (composition Pd=44.35%, Ag=
42.1%, Ir=3.0%, Cu=7.0%, Au=1.5%,
Production of alloy and sensor (Nb=0.5%, Ta=1.5%, V=0.05%) The raw materials are Pd, Ag, with 99.9% purity as in Example 1,
Ir, Cu and Au, and Nb, Ta with a purity of over 99.5%
and V were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 6 and are similar to the results of Example 1.

[Table] Example 7 Alloy number PAM-228 (composition Pd=49.66%, Ag=
43.0%, Ir=0.2%, Pt=0.1%, Cu=2.0%,
Au=5.0%, B=0.01, Y=0.01%, Nd=0.01,
Production of alloy and sensor (La = 0.01%) The raw materials are Pd, Ag, and 99.9% pure Pd, the same as in Example 1.
Ir, Pt, Cu and Au, B with a purity of 99.5% or more,
Y, Nd and La were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 7 and are similar to the results of Example 1.

[Table] Example 8 Alloy number PAM-231 (composition Pd=48.5%, Ag=
42.0%, Rh=2.0%, Os=2.0%, Hf=0.5%,
Production of alloy and sensor (Cu = 5.0%) The raw materials are the same 99.9% purity Pd and Ag as in Example 1,
Rh, Os, Hf, and Cu with a purity of 99.5% or higher were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 8 and are similar to the results of Example 1.

[Table] Example 9 Alloy number PAM-216 (composition Pd=48.5%, Ag=
42.0%, Rh=2.0%, Os=2.0%, Hf=0.5%,
Production of alloy and sensor (Au = 5.0%) The raw materials are Pd, Ag, and 99.9% pure Pd, the same as in Example 1.
Au, Rh, Os, and Hf with a purity of 99.5% or higher were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 9 and are similar to the results of Example 1.

[Table] Example 10 Alloy number PAM-246 (composition Pd=52.5%, Ag=
41.0%, Ir=2.0%, Rh=2.0%, Os=2.0%,
Hf=0.5%) Production of alloy and sensor The raw materials are Pd, Ag, and 99.9% pure Pd, the same as in Example 1.
Ir, Rh, Os, and Hf with a purity of 99.5% or higher were used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical properties and performance of the alloy sample and sensor are shown in Table 10 and are similar to the results of Example 1.

【table】

[Table] Example 11 Alloy number PAM-282 (composition Pd=52.0%, Ag=
41.5%, Rh=2.0%, Pt=2.0%, Os=2.0%,
Hf = 0.5%) Production of alloy and sensor The raw materials are Pd, Ag, with the same purity of 99.9% as in Example 1,
Ir and Pt, Rh, Os and more than 99.5% purity
Hf was used. The manufacturing method and experimental method are exactly the same as in Example 1. The electrical characteristics and performance of the alloy sample and sensor are shown in Table 11.
The results are similar to those of Example 1.

[Table] In addition to the above-mentioned Examples 1 to 11, experiments were also conducted on many alloys, and Table 12 shows the electrical properties, recrystallization temperature, average grain size, and The impedance change rate when a sensor using the alloy wire of the present invention is heated and held at 800°C for 10 days is shown.

[Table] As can be seen from Examples 1 to 11 and Table 12 below, the alloy of the present invention has constant electrical resistance properties of 100 ppm/℃ or less in a wide range of -150 to 1000℃ and excellent thermal stress fracture resistance. 7th
As shown in Figure 8, the major feature is that the change in electrical resistance with respect to temperature is significantly improved at high temperatures. Furthermore, as shown in Table 12, the performance of the sensor using the alloy of the present invention is extremely small, with Δη/η0×100 being less than ±0.015%, about 1/10 of that of the comparative alloy PA-4, and exhibiting excellent high-temperature stability. It can be seen that the characteristics of the alloy of the present invention can be fully exhibited. Here, the composition of the alloy of the present invention is Pd-Ag-(Ir, Pt,
Cu, Au) - (second selection component), silver 40.2 ~
The reason for limiting it to 43.0% is that it is outside this range.
Average temperature coefficient of electrical resistance is 0 to 100ppm/
℃ range, and excellent constant electrical resistance properties cannot be obtained, so the purpose of obtaining excellent thermal stress fracture resistance cannot be achieved. Next, iridium is the first selected component of the alloy of the present invention.
7.5% or less, platinum 5% or less, copper 7% or less, gold 9%
In the following ranges, as shown in Figures 2 to 6, the average temperature coefficient of electrical resistance between -150℃ and 1000℃ is less than 100ppm/℃, but beyond the upper limit of this range Since the average temperature coefficient of electrical resistance is 100 ppm/°C or more in all cases, the object of the present invention cannot be achieved, which is not preferable. These first-choice components iridium, platinum,
It was confirmed that copper and gold have the same effect within their composition ranges. Next, the general trend of the effect of adding the second selected component to the first invention alloy of the present application is as shown in Table 13, and the components that contribute to the improvement of the internal constant electrical resistance characteristics are Rh, Os,
In, Fe, Co, Ni, Ta, Re, Al, Tl, Ga, Si,
Sn, Y, Ti, Hf, Nb, Zn, Cd, Sb, Bi, B,
Rare earth elements and C, but if these components are added in excess of the upper limit of the composition in each claim,
This is not preferable because the constant electric resistance characteristics are not improved and all the characteristics are deteriorated. In addition, the components contributing to the heat stress fracture resistance in the second selected components of the alloy of the first invention of the present application are Rh, Os, In, Hf,
Fe, Co, Ni, V, Ta, Re, Al, Tl, Cr, Mo,
Si, Sn, Y, Ti, Nb, Zn, Cd, Sb, Bi, B,
Rare earth elements and C, but if these components are added in excess of the upper limit of the composition in each claim, Si,
The properties of all of them except Y, Ti, and Sb deteriorate. If the second selected component is outside the respective ranges, either or both of the constant electrical resistance properties (A) and the thermal stress fracture resistance (B) properties will deteriorate, which is not preferable. Pd-Ag (40.2-43.0%)-(Ir, Pt,
The general trend of the effect of adding the second selective component to Cu, Au)-based alloys is shown in Table 13 (1) and Table 13 (2).

【table】

【table】

[Table] As shown in (1) and (2) of Table 13 above, outside the limited composition range of the present invention, either constant electrical resistance property (A) or thermal stress fracture resistance (B) property or It's not good for both parties. Furthermore, in the method for manufacturing the alloy and sensor of the present invention, heat treatment is performed at 200 to 1200°C for 2 seconds or more.
The reason for limiting the temperature to 2 seconds or less is that within this temperature range and time, the internal strain caused by processing is sufficiently removed and even more stable constant electrical resistance characteristics are obtained. Due to residual stress caused by processing, constant electrical resistance characteristics cannot be obtained and the sensor becomes extremely unstable when used at high temperatures. In addition, if heat treatment is performed at 1200℃ or higher for 100 hours or more, thermal stress fracture resistance deteriorates due to coarsening of crystal grains, and furthermore, constant electrical resistance characteristics cannot be obtained due to the evaporation of silver contained, as well as evaporation. Electrical insulation may deteriorate due to silver contamination. Therefore, if the heat treatment conditions are deviated from the above, the sensor becomes unsuitable as a sensor with excellent constant electrical resistance characteristics or stability at high temperatures. In short, the alloy and sensor of the present invention are -150~
It has excellent constant electrical resistance characteristics with an average temperature coefficient of electrical resistance of 100 ppm/℃ or less in a temperature range of 1000℃, and excellent thermal stress fracture resistance, and even when used for long periods at high temperatures, the impedance change rate is ±0.005% or less. These alloys and sensors are used as main components of device complexes and various measuring instruments, such as heating elements, hot wire wind velocity, resistance thermometers, and thermometers. Even when applied to reference resistors such as constant current stabilizers, the excellent characteristics of the alloy and sensor of the present invention can be fully exhibited.

[Brief explanation of drawings]

Figure 1 shows the temperature of palladium-silver alloy from 0 to 400℃.
(), −150 to 1000℃ () and −200 to 1200℃
Characteristic diagrams showing the relationship between the average temperature coefficient of electrical resistance and the amount of Ag between temperatures in (), Figures 2 and 3
Figures 4 and 5 are respectively (Pd-Ag)
Characteristics showing the relationship between the average temperature coefficient of electrical resistance and Ag content at -150 to 1000°C for +Ir, (Pd-Ag) + Pt, (Pd-Ag) + Cu, and (Pd-Ag) + Au alloys. Figure 6 shows Ir in Pd-40%Ag alloy.
Characteristic diagrams showing the relationship between the amount of each element added and the average temperature coefficient of electrical resistance at -150 to 1000°C when Pt, Cu or Au is added. Figures 7 and 8 are alloy number PAM-115, PAM-214 and comparative alloys
FIG. 3 is a characteristic diagram showing the relationship between electrical resistance and measurement temperature of PA-4.

Claims (1)

[Claims] Iridium 7 as the first selected component in a weight ratio of 1
% or less, platinum 5% or less, copper 7% or less and gold 9%
A total of 0.1 to 10% of one or more of the following:
Second selection components: rhodium 5% or less, osmium 5% or less, hafnium 1% or less, indium 3
% or less, iron 2% or less, cobalt 2% or less, nickel 2% or less, niobium 1% or less, tantalum 2% or less, chromium 1.5% or less, molybdenum 1.5% or less, tungsten 0.2% or less, titanium 1% or less, yttrium 1 % or less, boron 0.5% or less, rare earth elements 1
% or less, carbon 0.5% or less, a total of 0.01 to 10% or less of one or more types, 40.2 to 43% silver, and the balance palladium, and the average temperature coefficient of electrical resistance in the temperature range of -150 to 1000℃. A constant electric resistance alloy characterized by having constant electric resistance characteristics of 100 ppm/℃ or less and heat stress fracture resistance. 2 Iridium 7 as the first choice component by weight
% or less, platinum 5% or less, copper 7% or less and gold 9%
A total of 0.1 to 10% of one or more of the following:
The second selected components include manganese 2% or less, rhenium 2% or less, thallium 2% or less, gallium 1.5% or less, aluminum 2% or less, vanadium 2% or less, silicon 1.5% or less, tin 1.5% or less, antimony 1% or less, Bismuth 1% or less, zinc 1% or less,
It consists of one type or two or more types of cadmium 1% or less, a total of 0.01 to 10% or less, silver 40.2 to 43%, and the balance palladium, and has an average temperature coefficient of electrical resistance of 100 ppm/ A constant electric resistance alloy characterized by having constant electric resistance characteristics below ℃ and heat stress fracture resistance.