KR102463644B1 - Copper alloy material for resistance material, manufacturing method thereof, and resistor - Google Patents

Abstract

Provided are a copper alloy material for a resistance material having both a small resistance temperature coefficient and good press formability, and a method for manufacturing the same. One copper alloy material for a resistance material contains 10 mass % or more and 14 mass % or less of manganese, 1 mass % or more and 3 mass % or less of nickel, the balance consists of copper and unavoidable impurities, and a crystal grain diameter is 8 micrometers or more and 60 micrometers. is below. Another copper alloy material for a resistance material contains 6 mass % or more and 8 mass % or less of manganese, 2 mass % or more and 4 mass % or less of tin, the balance consists of copper and unavoidable impurities, and has a crystal grain diameter of 8 µm or more and 60 µm or less to be.

Description

Copper alloy material for resistance material, manufacturing method thereof, and resistor

The present invention relates to a copper alloy material for a resistor, a method for manufacturing the same, and a resistor.

The metal material of the resistance material used for the resistor is required to have a small resistance temperature coefficient (hereinafter sometimes referred to as "TCR") so that the resistance of the resistor is stable even when the environmental temperature changes. The resistance temperature coefficient is a measure of the change in resistance value due to temperature expressed in parts per million per 1℃, TCR(×10 ^-6 /K)=(RR ₀ )/R ₀ ×1/(TT ₀ )× It is expressed as 10 ⁶ . Here, T in the formula is the test temperature (°C), T ₀ is the reference temperature (°C), R is the resistance value at the test temperature T (Ω), and R ₀ is the resistance value at the test temperature T ₀ (Ω) indicates Since a Cu-Mn-Ni alloy and a Cu-Mn-Sn alloy have very small TCR, they are widely used as a metal material which comprises a resistance material (refer patent document 1, for example).

With the recent miniaturization and high integration of electric and electronic components, the size reduction of the resistance material is also progressing. With this miniaturization, the influence of the dimensional accuracy at the time of manufacturing a resistance material by press-molding a metal material on the resistance value fluctuation|variation of a resistor is increasing, and improvement of the metal material press formability of a resistance material is calculated|required.

Japanese Patent Laid-Open No. 69724, 2016

An object of this invention is to provide the copper alloy material for resistance materials which has both a small resistance temperature coefficient and favorable press formability, and its manufacturing method. Moreover, this invention makes it a subject together to provide the resistor which has a stable resistance value even if environmental temperature changes, and the fluctuation|variation of a resistance value is small.

Copper alloy material for resistance material according to one embodiment of the present invention contains 10% by mass or more of manganese and 14% by mass or less of manganese, 1% by mass or more of nickel and 3% by mass or less of nickel, and the balance consists of copper and unavoidable impurities, and the grain size is Let it be the summary that they are 8 micrometers or more and 60 micrometers or less.

The copper alloy material for resistance material according to another aspect of the present invention contains 6% by mass or more and 8% by mass or less of manganese, 2% by mass or more and 4% by mass or less of tin, the balance consists of copper and unavoidable impurities, and the grain size is Let it be the summary that they are 8 micrometers or more and 60 micrometers or less.

The method for manufacturing a copper alloy material for a resistance material according to another aspect of the present invention is a method for manufacturing a copper alloy material for a resistance material according to the above aspect or the other aspect, wherein the copper alloy ingot is placed at 800°C or higher and 950°C or lower, 10 A homogenization heat treatment step in which heat treatment is performed for not less than a minute and not more than 10 hours, a hot working step in which hot working is performed on the ingot homogenized in the homogenization heat treatment step, and cold working at a working rate of 50% or more on the ingot subjected to hot working in the hot working step. An intermediate recrystallization annealing process in which recrystallization annealing is performed by performing heat treatment for 400 ° C or more and 700 ° C or less, 10 seconds or more and 10 hours or less to the ingot subjected to cold working in the intermediate cold working process, and intermediate A final cold working step in which the ingot subjected to recrystallization annealing is subjected to cold working at a working rate of 5% or more and 80% or less in the recrystallization annealing step, and 400° C. or more and 700° C. or less, 10 seconds to the ingot subjected to cold working in the final cold working step It is a summary to provide the final recrystallization annealing process which heat-processes more than 10 hours and performs recrystallization annealing.

The resistor according to another aspect of the present invention is composed of at least a part of the copper alloy material for a resistance material according to the one aspect or the other aspect as a summary.

The copper alloy material for resistance materials of this invention has a small resistance temperature coefficient and favorable press formability.

The manufacturing method of the copper alloy material for resistance materials of this invention can manufacture the copper alloy material for resistance materials which has both a small resistance temperature coefficient and favorable press formability.

The resistor of the present invention has a stable resistance value even when the environmental temperature changes, and the variation in the resistance value is small.

EMBODIMENT OF THE INVENTION One Embodiment of this invention is described in detail below.

The copper alloy material for resistance materials of 1st Embodiment contains 10 mass % or more and 14 mass % or less of manganese (Mn), 1 mass % or more and 3 mass % or less of nickel (Ni), balance is copper (Cu) and an unavoidable impurity and a crystal grain diameter of 8 µm or more and 60 µm or less. In addition, in the following, the copper alloy material for resistance materials of 1st Embodiment may be described as "Cu-Mn-Ni alloy material."

The copper alloy material for a resistance material of 2nd embodiment contains 6 mass % or more and 8 mass % or less of manganese, 2 mass % or more and 4 mass % or less of tin (Sn), remainder consists of copper and an unavoidable impurity, crystal grain diameter It is 8 micrometers or more and 60 micrometers or less. In addition, in the following, the copper alloy material for resistance materials of 2nd Embodiment may be described as "Cu-Mn-Sn alloy material."

Since the crystal grain diameter of the copper alloy material for resistance materials of these 1st and 2nd Embodiment is controlled to 8 micrometers or more and 60 micrometers or less, it has both a small resistance temperature coefficient and favorable press formability. Therefore, the copper alloy material for a resistance material of 1st and 2nd embodiment is suitable as a metal material which comprises the resistance material used for resistors, such as a shunt resistor, for example.

Since the copper alloy material for resistance materials of 1st and 2nd embodiment has a small resistance temperature coefficient, even if environmental temperature changes, a resistance value is stable. About the temperature coefficient of resistance of the copper alloy material for resistance materials of 1st and 2nd embodiment, the absolute value of the temperature coefficient of resistance in the range of 20 degreeC or more and 50 degrees C or less may be 50 ppm/K or less. When the temperature coefficient of resistance is within the above range, the stability of the resistance value when the environmental temperature changes is more favorable.

Moreover, since the copper alloy material for resistance materials of 1st and 2nd embodiment has favorable press formability, when a resistance material is manufactured by press-molding a copper alloy material, it is excellent in dimensional accuracy even if a resistance material is small. About the press formability of the copper alloy material for resistance materials of 1st and 2nd embodiment, a shear ratio can be used as an index|index. For example, if the shear ratio measured in accordance with the shear test method of copper and copper alloy thin plate jaws stipulated in the technical standard JCBA T310:2002 of the Japan New Copper Association is less than 85%, the press formability is more excellent, The dimensional accuracy in press molding is more excellent.

Moreover, the copper alloy material for resistance materials of 1st and 2nd embodiment is not limited to press formability, It is excellent also in the formability in another working method.

Since the copper alloy material for a resistance material of the first and second embodiments has excellent characteristics as described above, the resistor at least partially composed of the copper alloy material for a resistance material of the first or second embodiment changes in environmental temperature. The sea-island resistance value is stable, and the variation of the resistance value is small.

The copper alloy material for a resistance material of the first embodiment contains 10 mass % or more and 14 mass % or less of manganese and 1 mass % or more and 3 mass % or less of nickel, but when the manganese content is less than 10 mass %, the TCR is While there is a possibility of becoming large, the crystal grain diameter becomes large easily at the time of recrystallization annealing. On the other hand, when manganese content exceeds 14 mass %, while there exists a possibility that an electrical resistivity may become high, a crystal grain diameter becomes small easily at the time of recrystallization annealing. Moreover, there exists a possibility that corrosion resistance and manufacturability of the copper alloy material for resistance materials may fall.

Moreover, while there exists a possibility that TCR may become large that content of nickel is less than 1 mass %, the crystal grain diameter becomes large easily at the time of recrystallization annealing. Moreover, there exists a possibility that the corrosion resistance of the copper alloy material for resistance materials may fall. On the other hand, when content of nickel exceeds 3 mass %, while there exists a possibility that an electrical resistivity may become high, a crystal grain diameter becomes it easy to become small at the time of recrystallization annealing. Moreover, there exists a possibility that the manufacturability of the copper alloy material for resistance materials may fall.

The copper alloy material for a resistance material of the second embodiment contains 6 mass % or more and 8 mass % or less of manganese and 2 mass % or more and 4 mass % or less of tin, but when the manganese content is less than 6 mass %, the TCR is While there is a possibility of becoming large, the crystal grain diameter becomes large easily at the time of recrystallization annealing. On the other hand, when content of manganese exceeds 8 mass %, while there exists a possibility that an electrical resistivity may become high, a crystal grain diameter becomes small easily at the time of recrystallization annealing.

Moreover, while there exists a possibility that TCR may become large that content of tin is less than 2 mass %, the crystal grain diameter becomes large easily at the time of recrystallization annealing. Moreover, there exists a possibility that the corrosion resistance of the copper alloy material for resistance materials may fall. On the other hand, when content of tin exceeds 4 mass %, while there exists a possibility that an electrical resistivity may become high, a crystal grain diameter becomes small easily at the time of recrystallization annealing. Moreover, there exists a possibility that the manufacturability of the copper alloy material for resistance materials may fall.

The copper alloy material for resistance materials of the first embodiment may further contain alloy components other than manganese and nickel. In addition, the copper alloy material for resistance materials of 2nd Embodiment may contain alloy components other than manganese and tin further. Also in the copper alloy material for a resistance material of any embodiment, the alloy components that can be contained are iron (Fe) 0.001 mass % or more and 0.5 mass % or less, silicon (Si) 0.001 mass % or more and 0.1 mass % or less, chromium (Cr) 0.001 Mass % or more and 0.5 mass% or less, zirconium (Zr) 0.001 mass% or more and 0.2 mass% or less, titanium (Ti) 0.001 mass% or more and 0.2 mass% or less, silver (Ag) 0.001 mass% or more and 0.5 mass% or less, magnesium (Mg) ) 0.001 mass% or more and 0.5 mass% or less, cobalt (Co) 0.001 mass% or more and 0.1 mass% or less, phosphorus (P) 0.001 mass% or more and 0.1 mass% or less, and zinc (Zn) 0.001 mass% or more and 0.5 mass% or less It is 1 type, or 2 or more types of elements selected from the group which consists of.

By containing these alloy components, while the heat resistance of the copper alloy material for resistance materials improves, since growth of a crystal grain becomes slow at the time of recrystallization annealing, control of a crystal grain diameter becomes easier. When content of these alloy components exceeds the upper limit of the said range, there exists a possibility that the effect|action which suppresses the growth of a crystal grain may become too large. Moreover, while there exists a possibility that an electrical resistivity may become high, there exists a possibility that the manufacturability of the copper alloy material for resistance materials may fall.

The copper alloy material for a resistance material of the first embodiment has a crystal grain diameter in the above range and does not perform cold working after the final recrystallization annealing step to be described later, so that the Vickers hardness can be set to 90 HV or more and less than 150 HV, and 90 HV or more It is more preferable to set it as 135 HV or less. When the Vickers hardness of the copper alloy material for resistance materials of 1st Embodiment is less than 90 HV, a crystal grain diameter becomes large outside the above-mentioned range, and press formability may become inadequate. On the other hand, if it is 150 HV or more, it means that the crystal grain diameter is small outside the above-mentioned range, or cold working is performed after the final recrystallization annealing process, and a small resistance temperature coefficient may not be obtained.

The copper alloy material for a resistance material of the second embodiment has a crystal grain diameter in the above range and does not perform cold working after the final recrystallization annealing step to be described later, so that the Vickers hardness can be 80 HV or more and less than 120 HV, and 90 HV or more It is more preferable to set it as 105 HV or less. When the Vickers hardness of the copper alloy material for resistance materials of 2nd Embodiment is less than 80 HV, a crystal grain diameter becomes large outside the above-mentioned range, and press formability may become inadequate. On the other hand, if it is 120 HV or more, it means that the crystal grain diameter is small outside the above-mentioned range, or cold working is performed after the final recrystallization annealing process, and a small resistance temperature coefficient may not be obtained.

Next, the manufacturing method of the copper alloy material for resistance materials of 1st and 2nd embodiment is demonstrated. The copper alloy material for resistance materials of the first and second embodiments can be manufactured by the same method. That is, a homogenization heat treatment step of performing a heat treatment of 800° C. or more and 950° C. or less, 10 minutes or more and 10 hours or less to the copper alloy ingot, and a hot working step of performing hot working to the ingot homogenized in the homogenization heat treatment step, and hot working An intermediate cold working process in which the ingot subjected to hot working in the process is subjected to cold working at a working rate of 50% or more, and 400 ° C or more and 700 ° C or less to the ingot subjected to cold working in the intermediate cold working process, heat treatment for 10 seconds or more and 10 hours or less In the intermediate recrystallization annealing step of performing recrystallization annealing by performing the intermediate recrystallization annealing step, the final cold working step in which the ingot subjected to recrystallization annealing in the intermediate recrystallization annealing step is subjected to cold working at a working rate of 5% or more and 80% or less, and in the final cold working step It is a method comprising a final recrystallization annealing process in which the ingot subjected to cold working is subjected to heat treatment at 400° C. or higher and 700° C. or lower, for 10 seconds or longer and for 10 hours or less, and recrystallization annealing is performed.

With such a manufacturing method, the copper alloy material for resistance materials of 1st and 2nd embodiment whose crystal grain diameters are 8 micrometers or more and 60 micrometers or less can be manufactured. The copper alloy material for a resistance material of the first and second embodiments can be formed into a member of any shape, for example, can be formed into a wire rod, a bar material, a plate material, or the like. Hereinafter, as an example, the manufacturing method of the board|plate material comprised from the copper alloy material for resistance materials of 1st and 2nd embodiment is demonstrated.

First, a raw material is melted and cast using a furnace or the like to obtain an ingot having the above alloy component (casting step). Next, the ingot obtained in the casting process is heat-treated to homogenize the alloy component (homogenization heat treatment process). The conditions of the heat treatment in the homogenization heat treatment step may be appropriately set according to the alloy composition, and as an example, the conditions of 10 minutes or more and 10 hours or less at 800°C or more and 950°C or less are mentioned. When heating temperature is too high or heating time is too long, there exists a possibility that the workability of the copper alloy material for resistance materials may fall. On the other hand, if the heating temperature is too low or the heating time is too short, there is a fear that the homogenization of the alloy component becomes insufficient.

Then, hot working is performed on the ingot homogenized by the homogenization heat treatment process, and the ingot is shape|molded into the member of a desired shape (hot working process). For example, an ingot is hot-rolled and it shape|molds into the plate-shaped thing which makes|forms a substantially plate shape. Since the ingot immediately after completion of the homogenization heat treatment process is in a state heated to a high temperature, it is preferable to continuously transfer to the hot working process as it is and perform hot working. When the hot working is finished, the plate-shaped object is cooled at room temperature. Since an oxide film is formed on the surface of the plate-shaped object after the hot working process, the oxide film is removed (surface-cutting process).

Next, the plate-shaped object from which the oxide film has been removed is subjected to cold working at a working rate of 50% or more (intermediate cold working step). For example, a plate-shaped object is cold-rolled and plate|board thickness is thinned. When the working ratio is 50% or more, the material structure obtained up to the hot working step can be sufficiently refined, so that the finally obtained crystal grain diameter does not become too large, and it tends to be an appropriate size.

Then, the plate-shaped object which cold-worked in the intermediate|middle cold-working process and thinned the plate|board thickness is heat-processed, and recrystallization annealing is performed (intermediate recrystallization annealing process). The conditions of the heat treatment in the intermediate recrystallization annealing step may be appropriately set according to the alloy composition or the like, and as an example, the conditions of 400°C or more and 700°C or less for 10 seconds or more and 10 hours or less are mentioned. When the heating temperature is too high or the heating time is too long, the material structure obtained until the hot working process cannot be sufficiently refined, and there is a possibility that the crystal grain diameter finally obtained cannot be made small. On the other hand, when the heating temperature is too low or the heating time is too short, there is a fear that a recrystallized structure cannot be obtained or the recrystallized structure becomes too small and the finally obtained crystal grain diameter becomes small. For this heat treatment, a batch heat treatment in which the plate-shaped object is placed in a furnace to raise the temperature may be used, or a weekly heat treatment in which the plate-shaped object is continuously passed through the furnace in which the temperature has been increased may be used.

Next, the plate-like article subjected to recrystallization annealing in the intermediate recrystallization annealing step is subjected to cold working at a working rate of 5% or more and 80% or less (final cold working step). For example, a plate-shaped object is cold-rolled, plate|board thickness is further thinned, and it is set as desired thickness. When the working ratio exceeds 80%, there is a possibility that the finally obtained crystal grain diameter becomes small. On the other hand, when the working ratio is less than 5%, there is a possibility that a recrystallized structure cannot be obtained or the crystal grain diameter finally obtained becomes large.

Then, the plate-like material which cold-worked in the final cold working process and made plate|board thickness further thin is heat-processed, and recrystallization annealing is performed (final recrystallization annealing process). The conditions for the heat treatment in the final recrystallization annealing step may be appropriately set according to the alloy composition or the like, and as an example, the conditions of 400°C or more and 700°C or less for 10 seconds or more and 10 hours or less are mentioned. When heating temperature is too high or heating time is too long, there exists a possibility that the crystal grain diameter finally obtained may become large. On the other hand, when the heating temperature is too low or the heating time is too short, there is a fear that a recrystallized structure cannot be obtained or the crystal grain diameter finally obtained becomes small. For this heat treatment, a batch heat treatment in which the plate-like material is placed in a furnace to increase its temperature may be used, or a weekly heat treatment in which the plate-like material is continuously passed through the furnace in which the temperature has been raised may be used.

By the manufacturing method provided with the above processes, the board|plate material comprised from the copper alloy material for resistance materials of 1st and 2nd embodiment whose crystal grain diameters are 8 micrometers or more and 60 micrometers or less can be manufactured. Moreover, according to a manufacturing method and conditions, a crystal grain diameter may be 8 micrometers or more and 45 micrometers or less, and may be 8 micrometers or more and 25 micrometers or less. By the intermediate cold working process and the intermediate recrystallization annealing process, the material structure obtained by the hot working process is fully refine|miniaturized, and the desired crystal grain diameter is obtained by the final cold working process and the final recrystallization annealing process. However, the said intermediate cold working process and the intermediate|middle recrystallization annealing process may be performed once, respectively, and before performing a final cold working process, you may repeat each several times and may perform it repeatedly.

Moreover, you may perform processing, such as shape correction, oxide film removal, degreasing, and rust prevention, between an adjacent process and a process or after a final recrystallization annealing process. However, if any processing is performed after the final recrystallization annealing step, when the processing is light processing, there is a risk that the structure becomes non-uniform and stable TCR cannot be obtained. There is a risk that sex may become difficult. Therefore, it is preferable not to perform any processing after the final recrystallization annealing process.

In addition, this embodiment shows an example of this invention, and this invention is not limited to this embodiment. In addition, it is possible to add various changes or improvement to this embodiment, and the form to which such a change or improvement was added can also be included in this invention.

Example

The present invention will be described in more detail with reference to Examples and Comparative Examples below. An ingot having a predetermined alloy composition is produced by casting, heat-treated under the conditions of a heating temperature of 800° C. or more and 950° C. or less, and a heating time of 10 minutes or more and 10 hours or less to homogenize the alloy components, and then formed into a plate shape by hot rolling and water-cooled.

Next, the plate-shaped object obtained by hot rolling is chamfered to remove the oxide film on the surface, and then the plate-shaped object is cold-rolled at a predetermined working rate (intermediate cold working step), and then continues under predetermined conditions (heating). temperature and heating time) to perform recrystallization annealing (intermediate recrystallization annealing process). Further, the plate-like material is cold-rolled at a predetermined working rate (final cold working process), and then, heat treatment is performed under predetermined conditions (heating temperature and heating time) to perform recrystallization annealing (final recrystallization annealing process) to obtain a thickness A plate material of 0.2 mm was obtained.

The alloy composition is as shown in Tables 1 to 4, but the remainder other than the alloy components shown in Tables 1 to 4 is copper and unavoidable impurities. In addition, each condition of an intermediate cold working process, an intermediate|middle recrystallization annealing process, a final cold working process, and a final recrystallization annealing process is as showing in Tables 1-4. Table 1 is an example of the Cu-Mn-Ni alloy material which changed the alloy composition variously, and Table 2 is an example of the Cu-Mn-Sn alloy material which changed the alloy composition variously. In addition, Table 3 is an example of a Cu-Mn-Ni alloy material in which the conditions of the four processes are variously changed, and Table 4 is a Cu-Mn-Sn alloy material in which the conditions of the four processes are variously changed. is an example of In addition, the manufacturing conditions of Tables 1 and 2 are more preferable than the manufacturing conditions of Tables 3 and 4.

Various evaluations were performed about the board|plate materials of Examples 1-36 and Comparative Examples 1-36 shown in Tables 1-4. The content and method will be described below. In addition, an evaluation result is shown to Tables 5-8.

<About measurement of crystal grain diameter>

The crystal grain diameter was measured in accordance with the cutting method of the new crystal grain size test method prescribed in JIS H0501 (1986). That is, the plate material was cut along the rolling direction to expose the cross section, and the end face was subjected to wet mirror polishing. And after etching the polished surface, it observed using a metallographic microscope, and the crystal grain diameter was measured from the observation image.

<About X-ray diffraction>

X-ray diffraction by the θ-2θ method was performed on the surface of the plate material, and peaks of (111), (200), (220), (311), (222), (400), (331), (420) were obtained. It was detected, and the volume ratio and half value width were evaluated. Incidentally, the type of X-ray is Cu-Kα, the tube voltage is 40 kV, the tube current is 20 mA, and the sampling rate is 1°/min.

<About measurement of resistance temperature coefficient>

Based on the method prescribed|regulated to JIS C2526 (1994), the temperature coefficient of resistance in the range of 20 degreeC or more and 50 degrees C or less of a board|plate material was measured. When the absolute value of the resistance temperature coefficient in the range of 20 degreeC or more and 50 degrees C or less was 50 ppm/K or less, it was set as the pass, and in Tables 5-8, it showed with "circle" mark. When the absolute value of the temperature coefficient of resistance in the range of 20 degreeC or more and 50 degrees C or less was more than 50 ppm/K, it was set as the rejection, and in Tables 5-8, it showed with "x" mark.

<About evaluation of press formability>

The press formability of the sheet material was evaluated by the shear ratio measured in accordance with the shear test method for copper and copper alloy thin plate strips specified in JCBA T310:2002, the technical standard of the Japan Copper Association. That is, the sheet material was punched using a press machine, a square die, etc., a cross section (press fracture surface) perpendicular to the rolling direction of the sheet material was exposed, the cross section was observed using a scanning electron microscope, and the shear ratio was calculated. In addition, about the conditions in punching of a board|plate material, a clearance is 10 micrometers, a press speed is 200 mm/s, and lubrication conditions are non-lubricating.

When the shear ratio was less than 85%, it was evaluated that the press formability was excellent, and in Tables 5 to 8, it was indicated by "○". When the shear ratio was 85% or more, the press formability was evaluated as insufficient, and in Tables 5 to 8, it was indicated by "x".

<About measurement of Vickers hardness>

Based on the method prescribed|regulated to JIS Z2244 (2009), Vickers hardness was measured from the surface of a board|plate material. In addition, the load is 2.9N, and the reduction time of the indenter is 15s.

As can be seen from the results shown in Tables 5 to 8, the plate materials of Examples 1 to 36 have a small temperature coefficient of resistance and good press formability because the crystal grain diameters are 8 µm or more and 60 µm or less.

In contrast, Comparative Examples 1 to 8 are examples in which the alloy composition is outside the suitable range of the present invention, but the plate materials of Comparative Examples 1 to 7 have a grain diameter of 8 μm because the alloy composition is outside the suitable range of the present invention. It became less than or more than 60 micrometers, and it was not able to have a small resistance temperature coefficient and favorable press formability. Moreover, since the content of Mn was low in Comparative Example 1 and Comparative Example 4, even if the crystal grain diameter was within the prescribed range, a small resistance temperature coefficient was not obtained.

In Comparative Example 8, since the alloy composition was outside the suitable range of the present invention, cracks occurred in the plate-like article during hot rolling, and the plate material could not be obtained by proceeding to the subsequent process.

Comparative Examples 9 to 44 are examples in which the manufacturing conditions are outside the suitable range of the present invention, but the plates of Comparative Examples 9 to 14, 17 to 23, 26 to 32, 35 to 41, and 44 have the manufacturing conditions of the present invention. Because it was out of the suitable range, the grain diameter was less than 8 µm or more than 60 µm, and it was not possible to have a small resistance temperature coefficient and good press formability.

For the plates of Comparative Examples 15, 16, 24, 25, 33, 34, 42, and 43, the recrystallized structure could not be obtained by the final recrystallization annealing process because the manufacturing conditions were outside the suitable range of the present invention, and the low temperature coefficient of resistance and good press formability could not be achieved.

Claims (9)

A copper alloy material for resistance materials containing 10 mass % or more and 14 mass % or less of manganese, 1 mass % or more and 3 mass % or less of nickel, the balance being copper and unavoidable impurities, and having a crystal grain diameter of 8 µm or more and 60 µm or less. The method of claim 1,
Copper alloy material for resistance material having Vickers hardness of 90HV or more and 146HV or less. A copper alloy material for resistance materials containing 6 mass % or more and 8 mass % or less of manganese, 2 mass % or more and 4 mass % or less of tin, the balance being copper and unavoidable impurities, and having a crystal grain diameter of 8 µm or more and 60 µm or less. 4. The method of claim 3,
Copper alloy material for resistance material having Vickers hardness of 80HV or more and less than 120HV. 5. The method according to any one of claims 1 to 4,
Iron 0.001 mass % or more and 0.5 mass % or less, silicon 0.001 mass % or more and 0.1 mass % or less, chromium 0.001 mass % or more and 0.5 mass % or less, zirconium 0.001 mass % or more and 0.2 mass % or less, titanium 0.001 mass % or more and 0.2 mass % or less, Silver 0.001 mass % or more and 0.5 mass % or less, magnesium 0.001 mass % or more and 0.5 mass % or less, cobalt 0.001 mass % or more and 0.1 mass % or less, phosphorus 0.001 mass % or more and 0.1 mass % or less, and zinc 0.001 mass % or more and 0.5 mass % or less A copper alloy material for a resistance material further comprising one or two or more elements selected from the group consisting of 5. The method according to any one of claims 1 to 4,
The copper alloy material for resistance materials whose absolute value of the temperature coefficient of resistance in the range of 20 degreeC or more and 50 degrees C or less is 50 ppm/K or less. 5. The method according to any one of claims 1 to 4,
A copper alloy material for resistance materials having a shear ratio of less than 85%, measured in accordance with the shear test method for copper and copper alloy thin plate jaws stipulated in JCBA T310:2002, a technical standard of the Japan Progenitor Association. A method for producing the copper alloy material for a resistance material according to any one of claims 1 to 4, comprising:
A homogenization heat treatment step of performing a heat treatment of 800° C. or more and 950° C. or less, 10 minutes or more and 10 hours or less to the copper alloy ingot;
A hot working process of performing hot working on the ingot homogenized in the homogenization heat treatment process;
An intermediate cold working step of performing cold working at a working rate of 50% or more on the ingot subjected to hot working in the hot working step;
An intermediate recrystallization annealing step of performing recrystallization annealing by performing a heat treatment of 400° C. or more and 700° C. or less, 10 seconds or more and 10 hours or less, to the ingot subjected to cold working in the intermediate cold working step;
A final cold working step of performing cold working at a working rate of 5% or more and 80% or less on the ingot subjected to recrystallization annealing in the intermediate recrystallization annealing step;
Final recrystallization annealing process of performing recrystallization annealing by subjecting the ingot subjected to cold working in the final cold working process to heat treatment at 400° C. or more and 700° C. or less, for 10 seconds or more and 10 hours or less.
A method for producing a copper alloy material for a resistance material comprising: A resistor at least partially composed of the copper alloy material for a resistor according to any one of claims 1 to 4.