KR20190119573A - Copper alloy material for resistance materials and manufacturing method thereof, and resistor - Google Patents

Abstract

In the measurement of the electrical resistivity, an accurate measured value is easily obtained, and a copper alloy material for resistance materials having good laser weldability and a method of manufacturing the same are provided. The copper alloy material for resistance materials is a rolled plate of 0.04 mm or more when measured by a contact thickness gauge, and contains 2 to 14 mass% of manganese, and the balance consists of copper and unavoidable impurities. And when the roughness curve of the direction orthogonal to a rolling direction is acquired by the contact surface roughness measuring method with respect to the plate surface of a rolling board, the maximum height Rz is 0.3 micrometer or more and 1.5 micrometer or less, and the average length RSm of a roughness curve element is It is 0.03 mm or more and 0.15 mm or less, and the value of the parameter A computed by the following formula is 0.002 or more and 0.04 or less.

Description

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

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

The metal material of the resistor 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 stabilized even when the environmental temperature changes. The resistance temperature coefficient represents the magnitude of change in the resistance value due to temperature at a million fraction per 1 ° C, and TCR (× 10 ⁻⁶ / K) = (RR ₀ ) / R ₀ × 1 / (TT ₀ ) × 10 ⁶ . Where T in the formula is test temperature (° C.), T ₀ is reference temperature (° C.), R is resistance value (Ω) at test temperature T, and R ₀ is resistance value (Ω) at test temperature T ₀ . Indicates. Since Cu-Mn-Ni alloy and Cu-Mn-Sn alloy have very small TCR, it is widely used as a metal material which comprises a resistance material (for example, refer patent document 1).

When manufacturing a resistor, the electrically conductive material which consists of a resistance material and an oxygen free copper etc. is often welded. Conventionally, electron beam welding has been generally used for welding a resistance material and a electrically conductive material, but switching to laser welding is performed in anticipation of reducing manufacturing cost. In laser welding, it is known that the roughness of the surface to be welded is advantageous because the weldability decreases when the laser is reflected from the surface of the workpiece.

In addition, with the recent miniaturization and high integration of electrical and electronic components, miniaturization of resistors also progresses, and the sheet thickness of the resistor is also thinned. In the past, the influence of the surface properties (surface roughness, etc.) of the resistance material on the electrical resistivity was small and neglected. However, as the sheet thickness of the resistance material became thinner, the influence was inevitably increased. That is, conventionally, in view of workability, micrometers are used for the measurement of the sheet thickness of the resistance material, and the cross-sectional area is obtained from the measured value. However, if the surface roughness of the resistance material is rough, the apparent cross-sectional area of the resistance material calculated from the measured value by the micrometer is used. Since the difference between and the real cross-sectional area becomes large, the measured value of the electrical resistivity becomes larger than the real electrical resistivity. In connection with this, a difference arises between the dimension of the resistance material required at the time of manufacturing a resistor, and the dimension computed from the measured value of an electrical resistivity, and a problem arises in the design of a resistor.

Japanese Patent Laid-Open No. 2016 No. 69724

An object of the present invention is to provide a copper alloy material for resistance materials and a method for producing the same, which are easy to obtain accurate measured values in the measurement of electrical resistivity and have good laser weldability. Moreover, this invention makes it a subject to provide the resistor which has an accurate electric resistance value and is easy to manufacture.

The copper alloy material for resistance materials which concerns on one form of this invention contains 2 mass% or more and 14 mass% or less of manganese, and the remainder is a copper alloy material for resistance materials which consists of copper and an unavoidable impurity, and is measured by a contact thickness meter. The maximum height Rz is 0.3 µm or more and 1.5 µm when the sheet thickness t is a rolled sheet of 0.04 mm or more and a roughness curve in a direction orthogonal to the rolling direction is acquired by the contact surface roughness measurement method with respect to the plate surface of the rolled sheet. Hereinafter, let it be a summary that the average length RSm of an illuminance curve element is 0.03 mm or more and 0.15 mm or less, and the value of parameter A computed by the following formula is 0.002 or more and 0.04 or less.

Y _max in the following formula is the height of the highest mountain in the extraction part which extracts only the reference length l from the illuminance curve in the direction in which the average line extends. In the following formulas, y _i and y _{i +1} are i-th and i + 1 counted from one end in the direction in which the average line of the extraction portion extends when the measurement points of the illuminance curve existing in the extraction portion are respectively reference points. The height of the reference point present in the first. X _i and x _{i + 1} in the following formulas are the lengths in the direction in which the average line between one end of the direction in which the average line of the extract portion extends and the reference point in the i-th and i-th + 1th extends. N in the following formula is a numerical value indicating whether the reference point present at the position farthest from the one end in the direction in which the average line of the extraction portion extends is counted from one end in the direction in which the average line of the extraction portion extends, and is a numerical value indicating the fourth reference point. to be. T in the following formula is a sheet thickness of the rolled sheet in the case of measuring by a contact thickness meter.

<Equation 1>

The manufacturing method of the copper alloy material for resistance materials which concerns on another form of this invention is a method of manufacturing the copper alloy material for resistance materials which concerns on the said aspect, Comprising: The cold rolling is performed on the ingot of a copper alloy, it shape | molded in plate shape, and a rolling board An abrasive grain having a particle size of # 800 or more and # 2400 or less is used for the plate surface of the cold rolling step to be used, the recrystallization annealing step for recrystallization annealing to the rolled plate obtained in the cold rolling step, and the recrystallization annealing step in the recrystallization annealing step. It is a summary that the surface grinding process of performing buff polishing, and the re-cold rolling process of cold rolling of more than 0% and 50% or less of a rolling rate which grind | polished the plate surface in a surface grinding process are provided.

The resistor which concerns on another form of this invention is made into the summary that the at least one part consists of the copper alloy material for resistance materials of one said form.

The copper alloy material for resistance materials of this invention is easy to obtain an accurate measured value in the measurement of an electrical resistivity, and has favorable laser weldability.

The manufacturing method of the copper alloy material for resistance materials of this invention is easy to obtain an accurate measured value in the measurement of an electrical resistivity, and can manufacture the copper alloy material for resistance materials which has favorable laser weldability.

The resistor of the present invention has an accurate electrical resistance value and is easy to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS It is typical explanatory drawing explaining one Embodiment of the copper alloy material for resistance materials which concerns on this invention.

EMBODIMENT OF THE INVENTION One Embodiment of this invention is described in detail below. The copper alloy material for resistance materials of this embodiment contains 2 mass% or more and 14 mass% or less of manganese (Mn), and remainder consists of copper (Cu) and an unavoidable impurity. And the copper alloy material for resistance materials of this embodiment is a rolled plate with a plate thickness t of 0.04 mm or more when it measures with the contact thickness meter. In addition, when the roughness curve of the direction orthogonal to a rolling direction is acquired with the contact surface roughness measuring method with respect to the plate surface of a rolling board, the maximum height Rz is 0.3 micrometer or more and 1.5 micrometer or less, and the average length RSm of a roughness curve element is It is 0.03 mm or more and 0.15 mm or less, and the value of the parameter A computed by the following formula is 0.002 or more and 0.04 or less.

Y _max in the following formula is the height of the highest mountain in the extraction part which extracts only the reference length l from the illuminance curve in the direction in which the average line extends. In the following formulas, y _i and y _{i +1} are i-th and i + 1 counted from one end in the direction in which the average line of the extraction portion extends when the measurement points of the illuminance curve existing in the extraction portion are respectively reference points. The height of the reference point present in the first. X _i and x _{i + 1} in the following formulas are the lengths in the direction in which the average line between one end of the direction in which the average line of the extract portion extends and the reference point in the i-th and i-th + 1th extends. N in the following formula is a numerical value indicating whether the reference point present at the position farthest from the one end in the direction in which the average line of the extraction portion extends is counted from one end in the direction in which the average line of the extraction portion extends, and is a numerical value indicating the fourth reference point. to be. T in the following formula is a sheet thickness of the rolled sheet in the case of measuring by a contact thickness meter.

<Formula 2>

As described above, the copper alloy material for resistance materials of the present embodiment is appropriately controlled by the maximum height Rz, the average length RSm of the roughness curve element, and the parameter A (hereinafter, collectively referred to as "surface property"). Therefore, in the measurement of the electrical resistivity, an accurate electrical resistivity can be easily obtained and has good laser weldability. Therefore, the copper alloy material for resistance materials of this 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 this embodiment has the outstanding characteristics as mentioned above, the resistor in which at least one part was comprised from the copper alloy material for resistance materials of this embodiment has an accurate electrical resistance value, and is easy to manufacture.

Below, the copper alloy material for resistors and the resistor of the present embodiment will be described in more detail.

As mentioned above, the copper alloy material for resistance materials of this embodiment contains 2 mass% or more and 14 mass% or less of manganese, and remainder consists of copper and an unavoidable impurity. Content of manganese becomes like this. More preferably, they are 6 mass% or more and 14 mass% or less. If the content of manganese is less than 2% by mass, the TCR may be increased, and the material strength may be lowered to obtain the desired surface properties during manufacture. On the other hand, when content of manganese exceeds 14 mass%, there exists a possibility that an electrical resistivity may become high and corrosion resistance and manufacturability may fall. In addition, the material strength increases, and there is a fear that desired surface properties may not be obtained at the time of manufacture.

The copper alloy material for resistance materials of this embodiment may further contain alloy components other than manganese. Although the other alloy components which can be contained in the copper alloy material for resistance materials of this embodiment are not specifically limited, For example, more than 0 mass% of nickel (Ni) 3 mass% or less, and tin (Sn) more than 0 mass% 4 mass% Below 0 mass% of iron (Fe) 0.5 mass% or less, exceeding 0 mass% of silicon (Si) 0.1 mass% or less, exceeding 0 mass% of chromium (Cr) 0.5 mass% or less, and zirconium (Zr) exceeding 0 mass% 0.2 Mass% or less, Titanium (Ti) 0 mass% or more 0.2 mass% or less, Silver (Ag) 0 mass% or more 0.5 mass% or less, Magnesium (Mg) 0 mass% or more 0.5 mass% or less, cobalt (Co) 0 mass% It is 1 type, or 2 or more types of elements chosen from the group which consists of more than 0.1 mass% or less, more than 0 mass% of phosphorus (P), and 0.1 mass% or less of zinc (Zn), and more than 0 mass% of 0.5 (%) of zinc (Zn).

It is more preferable that at least one of nickel and tin is contained among the other alloy components which can be contained. It is more preferable that content of nickel is 0.001 mass% or more and 3 mass% or less, and it is more preferable that content of tin is 0.001 mass% or more and 4 mass% or less.

By containing these alloy components, the improvement of the material strength of the copper alloy material for resistance materials, the change of an electrical resistivity, the fall of TCR, the improvement of heat resistance, etc. can be expected. When content of these alloy components exceeds the upper limit of the said range, there exists a possibility that the electrical resistivity of the copper alloy material for resistance materials may become high too much, or manufacturability may fall. In addition, the material strength increases, and there is a fear that desired surface properties may not be obtained at the time of manufacture.

The copper alloy material for resistance materials of this embodiment is a rolled sheet whose plate | board thickness t is 0.04 mm or more when it measures with the contact thickness meter as mentioned above. As a contact type thickness measuring instrument, a micrometer etc. are mentioned, for example. From the sheet thickness t measured by the contact thickness meter, the external cross-sectional area of the rolled plate (or the resistance material manufactured from the copper alloy material for resistance materials) can be calculated. In order to obtain the true cross-sectional area of the rolled plate (or the resistor made of the copper alloy material for the resistor), it is necessary to consider the surface properties of the plate surface of the rolled plate.

If the plate thickness t of the rolled sheet is less than 0.04 mm, the influence of the surface properties on the measurement of the electrical resistivity becomes large, so that the electrical resistivity may be difficult to measure with high accuracy. Moreover, laser welding becomes difficult and there exists a possibility that it will become difficult to have favorable laser weldability.

The larger the plate thickness t of the rolled sheet is, the smaller the influence of the surface properties on the measurement of the electrical resistivity becomes, so that the electrical resistivity can be easily measured with high accuracy, and the laser weldability becomes good. Moreover, although the thickness of a resistance material is progressing with the miniaturization of a resistor, the plate | board thickness t from which the influence of the surface property on the measurement of an electrical resistivity becomes remarkable is about 0.3 mm.

The surface property (surface property of the plate surface of a rolled sheet) of the copper alloy material for resistance materials of this embodiment is as above-mentioned, and when the roughness curve of the direction orthogonal to a rolling direction is acquired by the contact surface roughness measuring method The maximum height Rz is 0.3 µm or more and 1.5 µm or less, the average length RSm of the illuminance curve element is 0.03 mm or more and 0.15 mm or less, and the value of the parameter A calculated by the above formula is 0.002 or more and 0.04 or less.

However, it is more preferable that the maximum height Rz is 0.5 µm or more and 1.5 µm or less, and the average length RSm of the roughness curve element is more preferably 0.03 mm or more and 0.1 mm or less, and the value of the parameter A calculated by the above formula is 0.004 or more and 0.028. It is more preferable that it is the following.

When the maximum height Rz, the average length RSm of the roughness curve element, and all of the parameters A are in the above numerical range, an accurate measurement value can be easily obtained in the measurement of the electrical resistivity, and a copper alloy material for resistance material having good laser weldability do.

When the maximum height Rz is less than 0.3 µm, the plate surface of the rolled sheet is too smooth, and there is a fear that the laser weldability is lowered. On the other hand, when the maximum height Rz is more than 1.5 µm, the plate surface of the rolled sheet is rough, and there is a fear that the electrical resistivity cannot be measured accurately.

When the average length RSm of a roughness curve element is less than 0.03 mm, since there are too many unevenness | corrugation which exists in the plate surface of a rolling board, there exists a possibility that an electrical resistivity cannot be measured correctly. On the other hand, when the average length RSm of a roughness curve element is more than 0.15 mm, since there are too few unevenness | corrugation which exists in the plate surface of a rolling board, there exists a possibility that laser weldability may fall.

The above formula for calculating the parameter A represents the relationship between the apparent cross-sectional area of the rolled plate and the cross-sectional area that increases from the real cross-sectional area under the influence of the surface properties of the plate surface, and the larger the value of the parameter A, It means that the difference between the apparent cross sectional area and the true cross sectional area is large.

Here, the above formula for calculating the parameter A will be described in detail with reference to FIG. 1. 1: is typical sectional drawing which shows the surface property of the rolled sheet of this embodiment, and the broken line extended in an X-axis direction is the roughness curve of the plate surface of a rolled sheet. The lower side of this roughness curve shows the inside of a rolling board, and the upper side shows the outside of a rolling board. Although a plurality of mountains and a plurality of valleys exist in the extraction portion in which only the reference length l is extracted from the roughness curve in the X-axis direction (that is, the direction in which the average line of the roughness curve extends), in this embodiment, the roughness curve is acquired. All the measuring points by the contact surface roughness measurement performed in order to do this are defined as reference points T. In contact surface roughness measurement, for example, 8000 measurement points (height information) are obtained at 0.0005 mm intervals.

In the example of FIG. 1, the reference points T ₁ , T ₂ , T ₃ , T ₄ ,..., In order from the one end (left end) in the X-axis direction of the extraction portion to the other end (right end). , T _{n -1} , T _n are present. And, in the example shown in Figure 1, because it is the highest mountain acid present in the position apart from one end (left end) of the X-axis direction, the extraction section, the apex of the mountain, that is, the reference point is the reference point T _{n -1} T will be _max . In Fig. 1, for convenience of explanation of the above equation, the peak of the mountain and the bottom of the valley are displayed as reference points, but the reference point is not limited to the peak of the mountain or the bottom of the valley, but the peak of the mountain and the bottom of the valley are shown. The point located in between may be a reference point.

Y ₁ , y ₂ , y ₃ , y ₄ ,. , y _{n -1} (y _max ), y _n represent the height (position in the Y-axis direction) of the reference point. ₁ , x ₂ , x ₃ , x ₄ ,. , x _{n -1} (x _max ), x _n is the length in the X-axis direction between the one end part (left end part) of the extracting part in the X-axis direction, and its reference point. Accordingly, the "x _{i + 1} -x _i" in the formula is, the distance in the X axis direction between the two reference points which are adjacent, and also means the height of the trapezoid portions into the hatching of one.

In addition, "(y _max -y _i )" in the said formula is the distance in the Y-axis direction between the reference point and the reference point _Tmax which it counts from the one end part (left end part) of the X-axis direction of a extraction part, and exists in the i-th direction. , Means the base length of the trapezoidal part which hatched in FIG. Therefore, "(y _max -y _i ) + (y _max -y _{i +1} )" in the said formula means the "sum of upper and lower bottoms" of the trapezoidal part which hatched in FIG.

Therefore, for "0.5x {(y _max -y _i ) + (y _max -y _{i +1} )} x (x _{i + 1} -x _i )", when i = 1 to i = n-1, (I.e., sum up to the reference point T _n at the position farthest from the reference point T _{1 at the} position closest to the one end (left end) in the X-axis direction of the extracting part). The difference between the cross-sectional area and the true cross-sectional area is calculated. If the result of the sum is doubled, the difference between the apparent cross-sectional area and the true cross-sectional area is calculated for both surfaces of the rolled sheet. By the influence of surface properties, the parameter A calculated by dividing the difference in the cross-sectional area by the product t × l (that is, the apparent cross-sectional area) of the plate thickness t and the reference length l of the rolled sheet measured by the contact thickness gauge is used. The magnitude of the difference between the apparent cross-sectional area and the true cross-sectional area that occurs can be evaluated.

If the value of parameter A is less than 0.002, the plate surface of a rolled sheet may be too smooth and laser weldability may fall. On the other hand, when the value of parameter A exceeds 0.04, since the difference of an apparent cross-sectional area and a real cross-sectional area becomes large, there exists a possibility that an electrical resistivity cannot be measured correctly.

Next, the manufacturing method of the copper alloy material for resistance materials of this embodiment is demonstrated. The copper alloy material for resistance materials of this embodiment cold-rolls ingot of a copper alloy, it shape | molds into plate shape, the cold rolling process which turns into a rolled plate, and the recrystallization annealing which performs recrystallization annealing on the rolled plate obtained by cold rolling process. It can manufacture by the method of providing the surface polishing process of performing the buff | polishing which uses the abrasive grains of particle size # 800 or more and # 2400 or less to the plate surface of the rolled plate which recrystallized-annealed by the recrystallization annealing process at the process.

By such a manufacturing method, an accurate measured value can be easily obtained in the measurement of an electrical resistivity, and the copper alloy material for resistance materials of this embodiment which has favorable laser weldability can be manufactured.

Below, a more specific example of the manufacturing method of the copper alloy material for resistance materials of this embodiment is shown as an example.

First, raw materials are melted and cast using a furnace or the like to obtain an ingot having the alloy component (casting step). Subsequently, the ingot obtained in the casting step is heat treated to homogenize the alloy components (homogenization heat treatment step). What is necessary is just to set conditions of the heat processing in a homogenization heat processing process suitably according to an alloy composition, As an example, the conditions of 10 minutes or more and 10 hours or less are 800 degreeC or more and 950 degrees C or less. If 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, when heating temperature is too low or heating time is too short, there exists a possibility that homogenization of an alloying component may become inadequate.

Subsequently, hot rolling is performed on the ingot homogenized by the homogenization heat treatment step, and the ingot is formed into a plate-like material (hot rolling step). Since the ingot immediately after the end of the homogenization heat treatment step is heated to a high temperature, it is preferable to transfer to the hot rolling step continuously and perform hot rolling as it is. When hot rolling is complete | finished, the plate-shaped object of an ingot is cooled at normal temperature. Since the oxide film is formed on the surface of the plate-like article after the hot rolling step, the oxide film is removed (face-fining step).

Next, cold rolling is performed to the plate-shaped object from which the oxide film was removed (cold rolling process). For example, a plate-like thing is cold-rolled, thin plate thickness, and it is set as a rolled plate. The rolling direction of a cold rolling process is made into the same direction as the rolling direction of a hot rolling process. The processing rate of cold rolling is not specifically limited, For example, it can be 50% or more. If the work rate in the cold rolling step is 50% or more, the material structure obtained up to the hot rolling step can be sufficiently refined by annealing under suitable conditions in the subsequent recrystallization annealing step, so that the final grain size obtained is too large. There is not and is easy to become appropriate size.

Subsequently, the rolled plate obtained in the cold rolling step is heat treated to perform recrystallization annealing (recrystallization annealing step). Although the conditions of the heat processing in a recrystallization annealing process may be suitably set according to an alloy composition etc., the conditions of 10 second or more and 10 hours or less for 10 second at 350 degreeC or more and 700 degrees C or less are mentioned as an example. If the heating temperature is too high or the heating time is too long, the material structure obtained by the hot rolling step cannot be sufficiently refined, and there is a possibility that the crystal grain diameter finally obtained cannot be reduced. On the other hand, if the heating temperature is too low or the heating time is too short, the recrystallized structure may not be obtained, or the recrystallized structure may become too small, resulting in a decrease in the finally obtained grain diameter. For this heat treatment, a batch heat treatment may be used in which a rolled plate is placed in a furnace to increase the temperature. Alternatively, a weekly heat treatment may be used in which the rolled plate is continuously passed through in a heated furnace.

Next, buff polishing using abrasive grains of particle size # 800 or more and # 2400 or less is performed on the plate surface of the rolled sheet subjected to recrystallization annealing in the recrystallization annealing process (surface polishing step). The polishing direction of buff polishing, that is, the relative movement direction of the plate surface of the rolled plate and the buffing is the same as the rolling direction of the cold rolling step and the rolling direction of the hot rolling step. If the grain size of the abrasive grain is less than # 800, the plate surface of the rolled sheet may be too rough, so that desired surface properties may not be obtained. On the other hand, when the particle size of the abrasive grains exceeds # 2400, the plate surface of the rolled sheet may be too smooth, and there is a fear that the desired surface properties may not be obtained.

Next, the cold rolling of 50% or less of the processing rate is performed to the rolled board which polished the plate surface in the surface grinding process (re-cold rolling process). For example, the rolled sheet is cold rolled, the thickness of the sheet is further thinned to a desired thickness. When the work rate in the re-cold rolling step exceeds 50%, the unevenness of the plate surface formed in the surface polishing step may be crushed by cold rolling, and there is a fear that desired surface properties may not be obtained.

In addition, this re-cold rolling process does not need to be performed. That is, you may make the processing rate of the process performed after a surface grinding | polishing process into 0%, without performing a re-cold rolling process.

In addition, the rolling direction of a re-cold rolling process shall be made into the same direction as the rolling direction of a cold rolling process, the rolling direction of a hot rolling process, and the grinding | polishing direction of buff polishing. And after manufacture of a rolled plate, although the roughness curve of the direction orthogonal to a rolling direction is acquired with respect to the plate surface, this rolling direction is the rolling direction of the cold rolling process or re-cold rolling process performed before a surface grinding | polishing process. It means the direction.

By the manufacturing method provided with the above processes, the rolled sheet which has the said surface property can be manufactured. By the surface polishing process and the re-cold rolling process, the surface properties are obtained. However, the cold rolling process and the recrystallization annealing process performed before the surface polishing process may be performed once each, or may be repeated several times each before performing the surface polishing process. In the casting step, the horizontal continuous casting method is employed, and in the casting step, if the ingot is formed into a plate-like material, the homogenization heat treatment step and the hot rolling step can be omitted. Moreover, you may process shape correction, oxide film removal, degreasing, rust prevention, etc. between the adjacent process and a process or after a final process (surface grinding process or re-cold rolling process). However, when performing after a surface grinding | polishing process or a re-cold rolling process, it is necessary to carry out so that surface property may not deviate from the range of this invention.

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

Example

An Example and a comparative example are shown to the following, and this invention is demonstrated to it further more concretely.

After the ingot having a predetermined alloy composition is produced by casting (casting step), heat treatment is performed at 800 ° C or more and 950 ° C or less for 10 minutes or more and 10 hours or less to homogenize the alloy components (homogenization heat treatment step), and then hot rolling is performed. Was formed into a plate shape and water-cooled (hot rolling step). Subsequently, the plate-shaped object obtained by hot rolling was subjected to the surface removal, and the surface oxide film was removed (a surface treatment step). Then, the plate-shaped object was cold rolled at a processing rate of 50% or more to thin the plate thickness to obtain a rolled plate (cold rolling). fair).

Next, this rolled sheet was heat-treated on 350 degreeC or more and 700 degrees C or less, 10 second or more, and 10 hours or less, and after recrystallization annealing (recrystallization annealing process), the buffing using abrasive grain was performed to the plate surface of a rolling plate. (Surface polishing process). Furthermore, cold rolling of 0% or more and 60% or less was performed to the rolling board which buff polishing was performed (re-cold rolling process), and the rolling board of 0.04 mm or more and 0.3 mm or less was obtained.

The alloy composition is as shown in Tables 1 and 2, but the balance other than the alloy components shown in Tables 1 and 2 is copper and unavoidable impurities. In addition, the particle size of the abrasive grain used at the surface grinding | polishing process, the working ratio of the cold rolling in a re-cold rolling process, and the plate | board thickness measured with the contact thickness meter of the obtained rolled sheet are as showing in Tables 1 and 2. Table 1 shows an example in the case of variously changing the alloy composition, and Table 2 shows an example in the case of variously changing the conditions of the surface polishing step and the re-cold rolling step. Moreover, the manufacturing conditions of Table 1 are more preferable than the manufacturing conditions of Table 2.

Various evaluation was performed about the rolled board of Examples 1-27 and Comparative Examples 1-14 shown in Table 1, 2. The content and method are demonstrated below. In addition, the evaluation results are shown in Tables 1 and 2.

<Evaluation of surface properties>

The surface roughness of the rolled sheet is measured by a method (contact surface roughness measuring method) according to the method specified in JIS B0601 (2001), and the roughness curve of the direction orthogonal to the rolling direction is obtained, and the maximum In addition to obtaining the height Rz and the average length RSm of the illuminance curve element, the illuminance curve was analyzed to obtain the value of the parameter A calculated by the above formula.

The contact surface roughness measuring method will be described in detail. The probe of diameter 2 micrometers was made to contact the plate surface of a rolling board, and the probe was slid in the direction orthogonal to a rolling direction on the conditions of 4 mm of sliding distance of a probe, and 0.1 mm / s of sliding speeds. Then, an illuminance curve was obtained by obtaining 8000 measurement points (height information) at intervals of 0.0005 mm. In addition, the cutoff length is 0.8 mm.

<Measurement of electrical resistivity>

Mirror surface polishing was performed to the plate surface of the rolled plate, and the electrical resistivity in 20 degreeC was measured by the method (four-terminal method) according to the method prescribed | regulated to JIS C2525 about each rolled board before and behind mirror polishing. The plate thickness of the rolled sheet was measured with a micrometer. And when the difference of the electrical resistivity before and behind mirror polishing is 2% or less, it was determined that the exact measured value was easy to be obtained in the measurement of an electrical resistivity, and it showed with "(circle)" display in Table 1. On the other hand, when the difference in electrical resistivity before and after mirror polishing was more than 2%, it was determined that the exact measured value was difficult to be obtained in the measurement of the electrical resistivity, and it was shown by "x" display in Table 1.

Further, since the difference between the apparent cross-sectional area and the true cross-sectional area of the rolled plate after mirror polishing is small, an electrical resistivity closer to the true electrical resistivity of the material is obtained. The maximum surface height Rz was 0.1-0.3 micrometer, the average length RSm of the roughness curve element was 0.2-0.5 mm, and the value of the parameter A was 0.001-0.002.

<About laser weldability evaluation>

The rolled plate and the electrically-conductive material which consisted of oxygen-free copper were matched, and the interface was welded by fiber laser welding. After the welding, a tensile test was conducted for a rectangular test piece welded in the tensile direction in a direction orthogonal to the welding direction by a method according to the method specified in JIS Z2241. And when the breaking strength of the test piece was 150 Mpa or more, it determined with the laser weldability favorable, and was shown by the "(circle)" display in Table 1. On the other hand, when the breaking strength of the test piece was less than 150 MPa, it was determined that laser weldability was poor, and in Table 1, it was indicated by "x" display.

As can be seen from the results shown in Tables 1 and 2, in the rolled sheets of Examples 1 to 27, the maximum height Rz was 0.3 µm or more and 1.5 µm or less, and the average length RSm of the roughness curve element was 0.03 mm or more and 0.15 mm or less. Since the value of the parameter A is 0.002 or more and 0.04 or less, accurate measurement value was easy to be obtained in the measurement of an electrical resistivity, and it had favorable laser weldability.

In contrast, in the rolled sheets of Comparative Examples 1 and 2, the alloy composition is an example out of the range of the present invention, but any one of the maximum height Rz, the average length RSm of the roughness curve element, and the value of the parameter A is in the above numerical range. In order to deviate from the above, in the measurement of the electrical resistivity, it is difficult to obtain an accurate measured value or the laser weldability is poor.

The rolling plates of Comparative Examples 3 to 6, Comparative Examples 8 to 12, and Comparative Example 14 are examples in which manufacturing conditions are out of the range of the present invention, but among the maximum height Rz, the average length RSm of the roughness curve element, and the value of parameter A Since either of these is out of the numerical range, accurate measurement values are difficult to obtain in the measurement of the electrical resistivity, or the laser weldability is poor.

Since the thickness of the rolled sheets of Comparative Examples 7, 13 was out of the range of the present invention, laser weldability was poor. In addition, since the value of parameter A deviated from the said numerical range, it was difficult to obtain an accurate measured value in the measurement of an electrical resistivity.

l: reference length
T: reference point

Claims (4)

As a copper alloy material for resistance materials containing 2 mass% or more and 14 mass% or less of manganese, and remainder consists of copper and an unavoidable impurity,
The plate thickness t in the case of measuring with a contact thickness meter is a rolled sheet of 0.04 mm or more,
When the roughness curve of the direction orthogonal to a rolling direction is acquired with the contact surface roughness measuring method with respect to the plate surface of the said rolling plate, the maximum height Rz is 0.3 micrometer or more and 1.5 micrometer or less, and the average length RSm of a roughness curve element is 0.03. Copper alloy material for resistance materials which are mm or more and 0.15 mm or less, and whose value of parameter A computed by the following formula is 0.002 or more and 0.04 or less.
(Y _max in the following formula | equation is the height of the highest mountain in the extraction part which extracted only the reference length l in the direction which the average line extends from the said roughness curve. Y _i and y _{i + 1} in the following formula | equation are the said In the case where the measurement points of the roughness curve present in the extract portion are used as reference points, respectively, it is the height of the reference point present in the i-th and i + 1 th counts from one end in the direction in which the average line of the extract portion extends. X _i and x _{i + 1} in the formulas are lengths in the direction in which the average line extends between one end of the direction in which the average line of the extract portion extends and the i-th and i + 1 th reference points. Is a reference point existing at a position farthest from one end of the direction in which the average line of the extract portion extends, and is counted from one end in the direction in which the average line of the extract portion extends. A numerical value indicating an acknowledgment. To the formula of t is, being the thickness of the rolled plate in the case of measurement by a contact thickness meter)
<Equation 1>

The method of claim 1,
More than 0 mass% of nickel, 3 mass% or less, more than 0 mass% of tin, 4 mass% or less, more than 0 mass% of iron, 0.5 mass% or less, more than 0 mass% of silicon, 0.1 mass% or less of chromium, more than 0 mass% of 0.5 mass%, More than 0 mass% of zirconium 0.2 mass% or less, More than 0 mass% of titanium 0.2 mass% or less, More than 0 mass% of 0.5 mass% or less, More than 0 mass% of magnesium more than 0.5 mass%, More than 0 mass% of cobalt 0.1 mass% or less, Copper alloy material for resistance materials which further contains 1 type (s) or 2 or more types of elements chosen from the group which consists of more than 0 mass% of phosphorus more than 0.1 mass%, and zinc more than 0 mass% and 0.5 mass% or less. As a method of manufacturing the copper alloy material for resistance materials according to claim 1 or 2,
Cold rolling process which cold-rolls ingot of copper alloy, shape | molds into plate shape, and makes a rolled plate,
A recrystallization annealing step of performing recrystallization annealing on the rolled sheet obtained in the cold rolling step;
A surface polishing step of performing buff polishing using abrasive grains having a particle size of # 800 or more and # 2400 or less on the plate surface of the rolled sheet subjected to recrystallization annealing in the recrystallization annealing step;
Re-cold rolling process which cold-rolls more than 0% of processing rate and 50% or less on rolling plate which polished plate surface in said surface grinding process
The manufacturing method of the copper alloy material for resistance materials provided with.  The resistor which consists of at least one part from the copper alloy material for resistance materials of Claim 1 or 2.

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