TWI623630B - Resistance material - Google Patents

Abstract

The electric resistance material of the present invention is composed of a Cu alloy containing Cu, 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15 mass% or more and 1.50 mass% or less of Si, and an absolute TCR at 25 ° C to 150 ° C. The value is 15 ppm/K or less.

Description

Resistance material

The present invention relates to resistive materials.

The resistor material used for the resistor of the current sensor or the like is a resistor material having a small variation in the value (resistance value) of the electric resistance near room temperature. Such a resistive material is generally known as a 12Mn-4Ni-Cu alloy containing Cu, Mn, and Ni, and a 7Mn-2.3Sn-Cu alloy. In addition, other alloy materials for electric resistance are disclosed in the "Electrical Laboratory Research Report No. 618 Related Precision Resistance Materials" Electric Test Laboratory, Showa 36 (1961) ) October, p.52-55 (hereinafter referred to as "Pingshan Paper") has been revealed.

JP-A-2006-270078 discloses an alloy for electric resistance containing Cu, Mn of 6 wt% or more and 12 wt% or less, Al of 1 wt% or more and 3 wt% or less, and Sn of 2 wt% or more and 3 wt% or less. material. Japanese Laid-Open Patent Publication No. 2006-270078 discloses a low-temperature side TCR [Temperature Coefficient of Resistance) of an alloy material for electric resistance from -55 ° C to 25 ° C, and a resistance value of a resistive material due to temperature change. The magnitude of the change, expressed as a value per million of 1K, and the high temperature side TCR from 25 ° C to 100 ° C. On the other hand, day The TCR of an alloy material for electric resistance containing a temperature region exceeding 100 ° C is not disclosed in Japanese Laid-Open Patent Publication No. 2006-270078.

Further, the Hirayama paper discloses a resistive material containing: Cu, 9 wt% or more and 14 wt% or less of Mn, and 0.25 wt% or more and 2 wt% or less of Si. The Pingshan paper reveals temperature coefficient α ₂₅ and β of the resistive material satisfying the above composition.

Here, in particular, the resistor used in the current sensor of the automobile battery is used because the remaining amount of the battery is calculated by integrating the current value flowing in the resistor, and thus the resistance value changes when the temperature of the resistor changes. If it is large, the current detection generates an error, and as a result, there is a problem that the remaining amount of the battery cannot be correctly grasped. Therefore, the resistor used in the high-precision current sensor is not limited to, for example, a temperature range of 25 ° C to 60 ° C (hereinafter referred to as "medium temperature side"), and is, for example, a low temperature side of -50 ° C to 25 ° C, And in a wide temperature range such as a high temperature side of 25 ° C to 150 ° C, the absolute value of TCR can be lowered, and the variation of the resistance value can be reduced. In particular, in automotive applications where the temperature around the resistor is likely to rise, in order to reduce the variation in the resistance value in a high-temperature environment, it is expected that the absolute value of the TCR on the high-temperature side of, for example, 25 ° C to 150 ° C can be 15 ppm / K or less.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-270078

[Non-Patent Document 1] Hirayama Hiroshi, "Electrical Laboratory Research Report No. 618 Research on Related Precision Resistance Materials", Electric Laboratory, Showa 36, October, p.52-55

However, the 12Mn-4Ni-Cu alloy and the 7Mn-2.3Sn-Cu alloy which are generally used as a resistive material have a small change in resistance value at room temperature, but have a resistance value change in a temperature range away from room temperature. The big problem is getting bigger. In particular, in the case of a high temperature side of 25 ° C to 150 ° C including a temperature region exceeding 100 ° C, there is a problem that the absolute value of TCR exceeds 15 ppm/K. This phenomenon has been confirmed by the inventor of this case. Therefore, in a wide temperature range including, for example, a temperature range of more than 100 ° C, for example, 25 ° C to 150 ° C, there is a problem that current cannot be detected with high precision.

Further, Japanese Laid-Open Patent Publication No. 2006-270078, as described above, does not disclose a TCR of an alloy material for electric resistance including a temperature region exceeding 100 °C. Therefore, similarly to the 12Mn-4Ni-Cu alloy and the 7Mn-2.3Sn-Cu alloy, the absolute value of the TCR of the alloy material for electric resistance exceeds 15 ppm in a temperature range of, for example, 25 ° C to 150 ° C including a temperature region exceeding 100 ° C. K, as a result, it is considered that there is a problem that the current cannot be detected with high precision in a wide temperature range including, for example, a temperature range of more than 100 ° C, for example, 25 ° C to 150 ° C.

Further, the electric resistance material described in the Hirayama paper also has a problem that the absolute value of TCR exceeds 15 ppm/K in a temperature range of, for example, 25 ° C to 150 ° C including a temperature region exceeding 100 ° C. This phenomenon has been confirmed by the inventors of the present invention based on the temperature coefficients α ₂₅ and β described in the Hirayama paper. Therefore, in a wide temperature range including, for example, a temperature range of more than 100 ° C, for example, 25 ° C to 150 ° C, there is a problem that current cannot be detected with high precision.

The present invention has been made to solve the above problems, and an object of the present invention is to provide that the absolute value of TCR can be lowered to, for example, 15 ppm/K or less in a wide temperature range including, for example, 25 ° C to 150 ° C in a temperature region exceeding 100 ° C. Resistance material.

The inventors of the present invention conducted intensive studies on the above problems, and as a result, found that the above problems can be solved by adjusting the Mn content and the Si content. In other words, the resistive material according to the present invention is composed of a Cu alloy containing Cu, 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15% by mass or more and 1.50% by mass or less of Si, at 25 ° C to 150 ° C. The absolute value of TCR in °C is 15 ppm/K or less.

The resistive material according to a layout of the present invention is constituted by a Cu alloy having the above composition, and has an absolute value of TCR of 15 ppm/K or less at 25 ° C to 150 ° C, even at 150 ° C of, for example, 25 ° C to over 100 ° C. In the high temperature region, the resistance value variation of the Cu alloy can still be reduced. Further, the absolute value of the TCR on the low temperature side of, for example, -50 ° C to 25 ° C can be lowered to 50 ppm / K or less (the composition can be adjusted to 30 ppm / K or less by more appropriate adjustment), and can be, for example, between 25 ° C and 60 ° C. The absolute value of the TCR on the temperature side is reduced to below 10 ppm/K. Thereby, in a wide temperature range including a temperature range of more than 100 ° C, for example, -50 ° C to 150 ° C, the absolute value of TCR can be lowered, so that not only the intermediate temperature side but also the variation of the resistance value of the Cu alloy can be reduced even in a wide temperature range. . Further, by the Cu alloy having the above composition, the volume resistivity of the resistive material can be sufficiently reduced to 40 × 10 ^-8 (Ω·m) or less, so that the volume resistivity of the Cu alloy can be suppressed from being large. A situation in which a large amount of Joule heat is generated when a current flows in a resistive material. Further, by consisting of a Cu alloy having the above composition, the absolute value of the thermoelectromotive force of copper can be sufficiently reduced to 2 μV/K or less. Therefore, when the resistive material is connected to a member mainly composed of Cu, the resistive material and the resistive material can be suppressed. The thermoelectromotive force caused by the temperature difference between the members becomes large. In addition, these have been confirmed by the examples described later. As a result, a resistive material which is particularly suitable for use in, for example, a resistor of a current sensor used in an automobile, in a wide range of temperatures from a low temperature to a high temperature such as -50 ° C to 150 ° C can be obtained.

In the Cu-based alloy, the total amount of the Mn content and the Si content in the Cu alloy is preferably 6.75 mass% or more and 8.40 mass% or less. According to this configuration, the absolute value of the TCR on the high temperature side of 25 ° C to 150 ° C can be surely set to 15 ppm / K or less.

According to the above-described resistive material of a layout, it is preferable that the TCR of -50 ° C to 25 ° C is 0 ppm / K or more and 50 ppm / K or less. According to this configuration, in the temperature range of the low temperature side of -50 ° C to 25 ° C, the fluctuation of the resistance value of the Cu alloy can be sufficiently reduced, and thus a resistor material which is applicable not only to the high temperature side but also to the low temperature side can be obtained.

According to the above-mentioned resistor material, it is preferable that the TCR absolute value of 25 ° C to 60 ° C is 10 ppm / K or less. According to this configuration, in the intermediate temperature range of 25 ° C to 60 ° C, the variation in the resistance value of the Cu alloy can be sufficiently reduced, and thus a resistor material which is applicable not only to the high temperature side but also to the intermediate temperature side can be obtained.

According to the present invention, as described above, it is possible to provide an absolute value of the TCR which can be lowered in a wide temperature range including, for example, -50 ° C to 150 ° C in a temperature region exceeding 100 ° C, in particular For example, the absolute value of the TCR on the high temperature side of 25 ° C to 150 ° C is lowered to a resistance material of 15 ppm / K or less.

Fig. 1 is a graph showing test results for confirming the effects of the present invention.

The resistive material of the present invention will be described in detail.

The electric resistance material of the present invention is used for detecting a current of a battery of a vehicle driven by an engine (internal combustion engine) or a current of a secondary battery of an electric vehicle including a hybrid electric vehicle, and a current sensor is used. Resistive material used in resistors. Among them, the current sensor used in the automobile is required to detect the current with high precision and suppress the battery or the secondary battery even when it is placed in a place where the temperature of the vehicle is near the heat source (engine, motor, etc.). Overcharged, overdischarged.

Here, the electric resistance material of the present invention is composed of a Cu alloy containing 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15% by mass or more and 1.50% by mass or less of Si. The Cu alloy may contain other elements in addition to the above-described Mn and Si, and examples thereof include Ni, Fe, Sn, Ge, and Mg.

Thereby, the absolute value of the TCR of the resistive material can be lowered in a wide temperature range including, for example, -50 ° C to 150 ° C in a temperature region exceeding 100 ° C. Specifically, the absolute value of the TCR on the low temperature side of -50 ° C to 25 ° C can be reduced to less than about 50 ppm / K, and 25 ° C to The absolute value of TCR on the medium temperature side of 60 ° C is lowered to about 10 ppm / K or less, and the absolute value of TCR on the high temperature side of 25 ° C to 150 ° C can be lowered to 15 ppm / K or less. Thereby, the resistance value variation of the Cu alloy can be lowered in a wide temperature range of, for example, -50 ° C to 150 ° C. As a result, a current sensor including a resistor using the resistive material of the present invention can detect a current with high precision in a wide temperature range.

Further, the volume resistivity of the resistive material of the present invention is sufficiently small to be about 40 × 10 ^-8 (Ω‧ m) or less. Thereby, it is possible to suppress a situation in which a large amount of Joule heat is generated when a current flows through the resistor due to a large volume resistivity of the Cu alloy. Further, the resistive material of the present invention is sufficiently smaller than the thermoelectromotive force (for the copper thermoelectromotive force) between the leads mainly composed of Cu and the resistor connected to the resistor in the current sensor to be about 2 μV/K or less. Thereby, it is possible to suppress a situation in which the thermoelectromotive force is increased due to the temperature difference between the resistor and the lead, and it is possible to suppress the generated thermoelectromotive force from becoming a measurement error of the current sensor. As a result, the current sensor can detect the current with high precision.

In addition, when the Mn content of the Cu alloy is more than 7.40% by mass, not only the volume resistivity of the Cu alloy but also the absolute value of the TCR on the intermediate temperature side and the absolute value of the TCR on the high temperature side become large. In addition, when the Mn content of the Cu alloy is less than 6.20% by mass, the absolute value of the TCR on the intermediate temperature side and the high temperature side of the Cu alloy becomes large.

Here, in particular, in order to reduce the absolute value of the TCR on the high temperature side, the electric resistance material of the present invention can more appropriately adjust the Mn content of the Cu alloy. Specifically, the Cu alloy constituting the resistive material of the present invention preferably contains 6.20% by mass or more and 7.33% by mass or less of Mn. Thereby, the absolute value of the TCR on the high temperature side can be reduced to about 12 ppm/K. under. Further, the Cu alloy more preferably contains Mn of about 6.30% by mass or more and about 6.87% by mass or less. Thereby, the absolute value of the TCR on the high temperature side can be further reduced to about 5.5 ppm/K or less. Further, the Cu alloy is particularly preferably contained in an amount of about 6.40% by mass or more and about 6.87% by mass or less of Mn. Thereby, the absolute value of the TCR on the high temperature side can be further reduced to about 3 ppm/K or less. Further, the Cu alloy preferably contains Mn of about 6.60% by mass or more and about 6.70% by mass or less. Thereby, the absolute value of the TCR on the high temperature side can be further reduced to about 2 ppm/K or less. The resistive material composed of the Cu alloy is particularly suitable for use in suppressing the absolute value of the TCR on the low temperature side and the absolute value of the TCR on the intermediate temperature side, and is suitable for use at a high temperature side of 25 ° C to 150 ° C in a wide temperature range. Resistance material.

In addition, when the Si content of the Cu alloy is more than 1.50% by mass, it is considered that the volume resistivity of the Cu alloy becomes large. In addition, when the Si content of the Cu alloy is less than 0.15% by mass, it is considered that the absolute value of the TCR of the Cu alloy on the low temperature side, the intermediate temperature side, and the high temperature side is large.

Further, in particular, in order to reduce the absolute value of the TCR on the low temperature side, the electric resistance material of the present invention can more appropriately adjust the Si content of the Cu alloy. Specifically, the Cu alloy constituting the resistive material of the present invention preferably contains Si of about 0.45 mass% or more and 1.50 mass% or less. Thereby, the absolute value of the TCR on the low temperature side can be lowered to about 30 ppm/K or less while suppressing the absolute value of the TCR on the intermediate temperature side and the absolute value of the TCR on the high temperature side.

Further, in particular, in order to reduce the absolute value of the TCR on the intermediate temperature side, the electric resistance material of the present invention preferably adjusts the Mn content and the Si content in the Cu alloy constituting the electric resistance material of the present invention. Specifically, in the Cu alloy, the Mn content ratio and the Si content ratio are combined. The content ratio is preferably about 6.75 mass% or more and about 8.40 mass% or less. In the Cu alloy, the total content of the Mn content and the Si content is preferably about 6.90% by mass or more and about 8.40% by mass or less. Thereby, the absolute value of the TCR on the middle temperature side can be lowered to about 7 ppm/K or less while suppressing the absolute value of the TCR on the low temperature side and the absolute value of the TCR on the high temperature side. In the Cu alloy, the total content of the Mn content and the Si content is preferably about 8.20% by mass or more and about 8.40% by mass or less. Thereby, the absolute value of the TCR on the low temperature side can be lowered to about 12 ppm/K or less, and the absolute value of the TCR on the middle temperature side can be lowered to about 4 ppm/K or less, while suppressing the increase in the absolute value of the TCR on the high temperature side.

Further, in order to lower the volume resistivity, the resistive material of the present invention preferably adjusts the Mn content and the Si content in the Cu alloy constituting the resistive material of the present invention. Specifically, in the Cu alloy, the total content of the Mn content and the Si content is preferably 6.75% by mass or more and about 7.00% by mass or less. Thereby, the volume resistivity can be lowered to about 29.5×10 ^-8 Ω·m or less while suppressing the increase in the absolute value of the TCR on the low temperature side, the medium temperature side, and the high temperature side.

In addition to the Mn, Si, and Cu, the Cu alloy may further contain Fe in an amount of about 0.10% by mass or more and about 1.00% by mass or less. At this time, the Cu alloy preferably contains about 0.50% by mass or more and about 1.00% by mass or less of Fe. Further, in the electric resistance material of the present invention, in order to lower the absolute value of TCR, it is preferable to adjust the Si content and the Fe content in the Cu alloy constituting the electric resistance material of the present invention. Specifically, in the Cu alloy, the total content of the Si content and the Fe content is preferably about 1.00% by mass or more and about 1.70% by mass or less. Thereby, the absolute value of the TCR can be lowered over a wide temperature range.

Further, the Cu alloy may contain a trace amount of Mg of about 0.001% by mass or more and about 0.01% by mass or less as a deoxidizing material.

Further, the Cu alloy may contain Ni in an amount of about 0.15 mass% or more and about 0.30 mass% or less in order to improve corrosion resistance.

Further, the resistor material of the present invention can also be used for applications other than resistors for detecting current sensors for automotive batteries and secondary battery currents. Further, the resistive material of the present invention is particularly suitable for applications in which the ambient temperature fluctuates over a wide temperature range from low temperature to high temperature.

In the method for producing a resistive material made of a Cu alloy according to the present invention, the raw material is placed in a general vacuum melting furnace, melted, and then cooled to produce an ingot (block) of a Cu alloy. Then, the ingot of the Cu alloy is rolled, formed, or the like into a shape used for a resistive material such as a resistor. Here, in the Cu alloy of the present invention, for example, the 7Mn-2.3Sn-Cu alloy is not intentionally contained in Sn, so that Sn segregation hardly occurs. As a result, the unevenness of the resistance material can be suppressed, and the variation in the volume resistance value can be suppressed. Further, after rolling or the like, it is preferred to carry out a predetermined time heat treatment in an inert gas atmosphere at a temperature of about 600 ° C or more and about 850 ° C or less to remove internal strain generated when rolling or the like.

(Example)

Next, the Cu alloy constituting the resistive material of the present invention is actually produced and investigated. Sex.

Cu alloys of Examples 1 to 16 and Comparative Examples 1 and 2 having the compositions shown in Table 1 were produced. In addition, "0.00" in Table 1 means less than 0.01% by mass. Each of the Cu alloys of Examples 1 to 16 contains 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15% by mass or more and 1.50% by mass or less of Si. On the other hand, the Cu alloys of Examples 1 to 16 did not intentionally contain Sn. On the other hand, the Cu alloy of Comparative Example 1 contained Mn of less than 6.20% by mass, and the Cu alloy of Comparative Example 2 contained Mn of more than 7.40% by mass. Further, in the Cu alloys of Comparative Examples 3 and 4, a 12Mn-4Ni-Cu alloy and a 7Mn-2.3Sn-Cu alloy were separately prepared. The Cu alloys of Comparative Examples 3 and 4 were not intentionally containing Si.

Then, the volume resistivity, TCR, and average copper thermoelectromotive force of the Cu alloys of Examples 1 to 7 and Comparative Examples 1 to 4 were obtained, respectively. Further, the volume resistivity and TCR of Examples 8 to 16 were obtained, respectively.

The volume resistivity was measured according to the conductor resistance and volume resistivity test method of the metal resistor material prescribed in JIS-C2525, and the test piece composed of the Cu alloys of Examples 1 to 16 and Comparative Examples 1 to 4 was calculated. The resistance value per unit area and unit length at °C ± 2 ° C, the volume resistivity at 23 ° C was obtained.

The measurement of TCR was carried out according to the resistance-temperature characteristic test method specified in JIS-C2526, and the test piece composed of the Cu alloys of Examples 1 to 16 and Comparative Examples 1 to 4 was measured to have a temperature change from -50 ° C to 150 ° C. The resistance value at the time. The change in resistance value is shown in Figure 1. In addition, FIG. 1 shows the rate of change of the resistance value at a predetermined temperature T (-50 ° C ≦ T ≦ 150 ° C) based on 20 ° C ((= resistance value at T - resistance value at 20 ° C) ) / resistance value at 20 ° C) × 100) (%) map. Further, in Fig. 1, the resistance value change rates of the first to eighth embodiments are indicated by thick lines, and the resistance value change rates of the comparative examples 1 to 4 are indicated by thin lines.

Then, divide the difference between the resistance value (R ₂₅ ) at 25 ° C (reference temperature) and the resistance value (R - ₅₀ ) at -50 ° C by the temperature difference between 25 ° C and -50 ° C (△T _L =- At 75 ° C), TCR (= (R _{25 -} R - ₅₀ ) / ΔT _L × 10 ⁶ ppm / K) on the low temperature side of -50 ° C to 25 ° C was obtained. Further, the difference between the resistance value (R ₆₀ ) at ₆₀ ° C and the resistance value (R ₂₅ ) at 25 ° C was divided by the temperature difference between 25 ° C and 60 ° C (ΔT _M = 35 ° C) to obtain 25 TCR (=(R ₆₀ -R ₂₅ )/ΔT _M ×10 ⁶ ppm/K) on the medium temperature side from °C to 60 °C. Further, the difference between the resistance value (R ₁₅₀ ) at ₁₅₀ ° C and the resistance value (R ₂₅ ) at 25 ° C was divided by the temperature difference between 25 ° C and 150 ° C (ΔT _H = 125 ° C) to obtain 25 TCR (=(R ₁₅₀ -R ₂₅ )/ΔT _H ×10 ⁶ ppm/K) on the high temperature side from °C to 150 °C.

The measurement of the copper thermoelectromotive force was carried out according to the thermoelectromotive force test method of the metal resistance material specified in JIS-C2527, and the test piece composed of the Cu alloys of Examples 1 to 7 and Comparative Examples 1 and 2 and the standard copper wire were measured. The average is generated between the copper thermoelectromotive force. At this time, the copper thermoelectromotive force generated in one of the test piece or the standard copper wire is set to 0 ° C and the other is set to 100 ° C, and the temperature difference (100 ° C) is divided by The Cu alloys of Examples 1 to 7 and Comparative Examples 1 and 2 were averaged to copper thermoelectromotive force (μV/K).

Table 2 below shows the volume resistivity of the Cu alloys of Examples 1 to 16 and Comparative Examples 1 to 4, the respective TCRs on the low temperature side, the medium temperature side, and the high temperature side, and the average copper thermoelectromotive force. Further, the Cu alloys of Examples 8 to 16 did not obtain an average copper thermoelectromotive force.

Furthermore, Table 2 describes the target characteristics. The target characteristics are the values of the TCR on the low temperature side, the medium temperature side, and the high temperature side, and the average on the copper thermoelectromotive force which the resistive material (Cu alloy) of the present invention should satisfy. In addition, in Table 2, the values that are not satisfied with the target characteristics are hatched around the values.

[Table 2]

Further, Table 3 shown below is a composition, a workability, and temperature coefficients α ₂₅ and β of 16 kinds of Cu alloys containing Si described in the Hirayama paper. Further, 16 kinds of Cu alloys were set as Comparative Examples 11 to 26, respectively. Further, Table 4 below shows the volume resistivity and the average versus copper thermoelectromotive force (0 ° C to 50 ° C) of the Cu alloys of Comparative Examples 11 to 26 described in the Hirayama paper.

Then, from the temperature coefficients α ₂₅ and β described in the Hirayama paper, the TCRs on the low temperature side, the medium temperature side, and the high temperature side of the Cu alloys of Comparative Examples 11 to 26 were calculated. In a specific calculation method, the resistance value R _T (Ω) at a temperature T (-50 ° C ≦ T ≦ 150 ° C) is calculated using the temperature coefficients α ₂₅ and β according to the following equation (1).

(Number 1) R _T = R ₂₅ (1 + α ₂₅ × (T-25) + β × (T-25) ² ) (1)

Among them, R ₂₅ is a resistance value (Ω) at 25 ° C.

Further, when 25 ° C is used as the reference temperature, the TCR (ppm/K) at the temperature T (-50 ° C, 60 ° C, and 150 ° C) is calculated according to the following formula (2).

(Number 2) TCR=((R _T -R ₂₅ )/(R ₂₅ ×(T-25)))×10 ⁶ ‧‧‧(2)

Formula (3) is calculated by substituting the above formula (1) into the above formula (2).

(Number 3) TCR=((α ₂₅ ×(T-25)+β×(T-25) ² )/(T-25))×10 ⁶ ‧‧‧(3)

This formula (3) calculates the temperature coefficients α ₂₅ and β, and T (-50 ° C, 60 ° C and 150 ° C) of the Cu alloys of Comparative Examples 11 to 26, respectively, to calculate Comparative Examples 11 to 26, respectively. The TCR of the low temperature side, the medium temperature side, and the high temperature side of the Cu alloy. The results are shown in Table 4 above. In addition, in Table 4, the values that are not satisfied with the target characteristics are hatched around the numerical values.

As a result of the examples, first, it can be confirmed from the graphs shown in Fig. 1 that the rate of change in the resistance value of the Cu alloys of Examples 1 to 8 tends to be small with respect to temperature change, and on the other hand, Cu of Comparative Examples 1 to 4. The rate of change in the resistance value of the alloy tends to be large with respect to temperature changes.

In addition, as shown in Table 2, Examples 1 to 16 containing 6.2% by mass or more and 7.40% by mass or less of Mn and 0.15% by mass or more and 1.50% by mass or less of Si. In the Cu alloy, the absolute value of the TCR on the low temperature side can be set to 50 ppm/K or less, the absolute value of the TCR on the intermediate temperature side is set to 10 ppm/K or less, and the absolute value of the TCR on the high temperature side is set to 15 ppm/K or less. It can be known that any of the embodiments 1 to 16 satisfies the target characteristics of the TCR. From this phenomenon, it was confirmed that the Cu alloys of Examples 1 to 16 exhibited small fluctuations in the resistance value in a wide temperature range of -50 ° C to 150 ° C. As a result, the Cu alloys of Examples 1 to 16 were used for the current of the resistor. The sensor detects current with high precision.

On the other hand, it was found that the absolute values of TCR on the high temperature side of the Cu alloys of Comparative Examples 3 and 4 which did not contain Si exceeded 15 ppm/K, and the target characteristics were not satisfied. Further, it was found that the absolute value of the TCR on the low temperature side of the Cu alloy system of Comparative Example 3 exceeded 50 ppm/K, and the target characteristics were not satisfied.

Therefore, from the results of Examples 1 to 16 and Comparative Examples 3 and 4, it was confirmed that Si is contained in the Cu alloy constituting the resistive material, and not only the absolute value of TCR on the low temperature side and the medium temperature side but also the absolute value of TCR on the high temperature side. Can also be reduced.

Further, even in the Cu alloys of Comparative Examples 1 and 2 containing Si, Comparative Example 1 composed of a Cu alloy containing not more than 6.20% by mass of Mn, and Cu alloy containing Mn exceeding 7.4% by mass were used. In Comparative Example 2, the TCR on the medium temperature side and the high temperature side did not satisfy the target characteristics.

In addition, as shown in Tables 3 and 4, even in the Cu alloy of Comparative Examples 11 to 26 described in the Hirayama paper containing 9% by mass or more of Mn, the absolute value of the TCR on the high temperature side is still larger than 15 ppm/K. The target characteristics are not met. Also, Comparative Examples 11 to 14, 16 to 22, In addition to the high temperature side of the 24 and 26 series, the TCR on the middle temperature side did not satisfy the target characteristics. Further, in Comparative Example 25, in addition to the high temperature side, the TCR on the low temperature side did not satisfy the target characteristics.

By the results of the examples 1 to 16 and the comparative examples 1, 2, and 11 to 26, it was confirmed that the Cu alloy constituting the resistive material contained 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15% by mass. The above Si and 1.50% by mass or less can reduce the absolute value of each TCR on the low temperature side, the medium temperature side, and the high temperature side.

In addition, the volume resistivity of the Cu alloy of any of Examples 1 to 16 was 40 × 10 ^-8 (Ω·m·m) or less, and it was confirmed that the volume resistivity was sufficiently small. As a result, it was confirmed that the current sensor can suppress a large amount of Joule heat generated when a current flows through the resistor due to a large volume resistivity of the Cu alloy. Further, in the Cu alloys of any of Examples 1 to 7, the absolute value of the copper thermoelectromotive force was 0.75 μV/K or less (2 μV/K or less), and it was confirmed that the Cu-electromotive force was sufficiently small. From this, it was confirmed that the Cu alloys of Examples 1 to 7 were used in a current sensor of a resistor, and it was possible to suppress the occurrence of Joule heat when a current flows through the resistor. Further, in the Cu alloys of Examples 8 to 16, the absolute value of the Cu thermoelectromotive force was 2 μV/K or less on average, and it is presumed that the Cu alloys of Examples 8 to 16 were used for the current sensor of the resistor, and the resistor was suppressed. The case where Joule heat is generated when a current flows.

In addition, as a result of Examples 1 to 16, when the Cu alloy contains 6.20% by mass or more and 7.30% by mass or less of Mn (in the cases of Examples 1 to 4 and 6 to 16), the content is different from In the case of 7.30 mass% of Mn (Example 5), the absolute value of the TCR on the high temperature side can be lowered to 12 ppm/K or less. This can be confirmed by Cu The alloy contains 6.20% by mass or more and 7.30% by mass or less of Mn, and the absolute value of each TCR on the high temperature side can be further reduced.

Further, from the results of Examples 1 to 4 and 6 to 16, it is known that the Cu alloy contains 6.30% by mass or more and 6.87% by mass or less of Mn (Examples 1, 4, 6, 8, and 13 to 15). In the case of Mn containing less than 6.30 mass% (Examples 3 and 16) and Mn containing more than 6.87 mass% (Examples 2, 7, and 9 to 12), the high temperature side can be used. The absolute value of TCR is reduced to below 5.5 ppm/K. In this way, it is confirmed that the Cu alloy contains 6.30% by mass or more and 6.87% by mass or less of Mn, and the absolute value of the TCR on the high temperature side can be further lowered.

Further, from the results of Examples 1, 4, 6, 8, and 13 to 15, it is known that the Cu alloy contains 6.40% by mass or more and 6.77% by mass or less of Mn (Examples 1, 4, 6, and 8, In the case of 13 and 14, in the case of containing Mn of less than 6.40% by mass (Example 15), the absolute value of the TCR on the high temperature side can be lowered to 3 ppm/K or less. Further, from the results of Examples 1, 4, 6, 8, 13, and 14, it is known that the Cu alloy contains 6.60% by mass or more and 6.70% by mass or less of Mn (in the cases of Examples 1 and 13), When the Mn content is less than 6.60% by mass (Examples 6 and 14) and the case where Mn is more than 6.70% by mass (Examples 4 and 8), the absolute value of the TCR on the high temperature side can be lowered to 2 ppm/K. the following. By this, it is confirmed that the Cu alloy is contained in an amount of 6.40% by mass or more and 6.87% by mass or less (more preferably 6.60% by mass or more and 6.70% by mass or less) of Mn, and the absolute value of the TCR on the high temperature side can be further lowered.

Further, from the results of Examples 1 to 16, it was found that the Cu alloy system contained 0.45 mass. When the amount of Si is 1.5% or more and 1.50% by mass or less (in the case of Examples 1 to 8 and 10 to 16), unlike the case where Si is less than 0.45% by mass (Example 9), the TCR on the low temperature side can be used. The absolute value is reduced to below 30 ppm/K. In this way, it is confirmed that Si is contained in an amount of 0.45 mass% or more and 1.50 mass% or less by the Cu alloy, and the absolute value of the TCR on the low temperature side can be further lowered.

In addition, as a result of the results of the examples 1 to 16 and the comparative examples 1 and 2, the total content of the Mn content and the Si content in the Cu alloy is 6.75 mass% or more and 8.40 mass% or less. In the case of the examples 1 to 16 , the case where the total content ratio is less than 6.75 mass % (comparative example 1) and the total content ratio exceeds 8.40 mass % (comparative example 2), the target characteristics of the TCR can be satisfied.

In addition, as a result of the examples 1 to 16, the total content of the Mn content and the Si content in the Cu alloy is 6.90% by mass or more and 8.40% by mass or less (Examples 1 to 14) In the case where the total content ratio is less than 6.90% by mass (Examples 15 and 16), the absolute value of the TCR on the intermediate temperature side can be further reduced to 7 ppm/K or less. On the other hand, in the Cu alloy, when the total content of the Mn content and the Si content is 6.75 mass% or more and 6.90 mass% or less (Examples 15 and 16), the volume resistivity can be lowered to 28.5. ×10 ^-8 Ω‧m or less.

In addition, as a result of Examples 1 to 14, the total content of the Mn content and the Si content in the Cu alloy is 8.20% by mass or more and 8.40% by mass or less (in the case of Examples 4 and 7). When the total content rate is less than 8.20% by mass (Examples 1 to 3, 5, 6, and 8 to 14), the absolute value of the TCR on the low temperature side can be further lowered. As low as 12ppm/K or less, the absolute value of TCR on the middle temperature side can be further reduced to below 4ppm/K.

In the Cu alloy, the total content of the Mn content and the Si content is 6.75 mass% or more and 7.00 mass% or less (in the case of the examples 14 to 16). When the total content ratio exceeds 7.00% by mass (Examples 1 to 13), the volume resistivity can be lowered to 29.5 × 10 ^-8 Ω ‧ m or less.

In addition, as a result of Examples 2, 5, and 10 to 16 in which the Si content is about 0.5% by mass, it is found that the Cu alloy contains 6.40% by mass or more and 6.70% by mass or less of Mn (Example 13 and In the case of 14), it is different from the case where Mn is less than 6.40% by mass (Examples 15 and 16), and when Mn is more than 6.70% by mass (in the case of Examples 2, 5 and 10 to 12), The absolute value of the TCR on the high temperature side can be further reduced to 3 ppm/K or less, and the absolute value of the TCR on the middle temperature side can be further reduced to 4.5 ppm/K or less.

In addition, it was confirmed from the results of Example 8 that the target characteristics can be satisfied even if the Cu alloy further contains 1.00% by mass or less (0.72% by mass) of Fe. Further, from the results of Examples 4 and 8, it was confirmed that the part of Si of the Cu alloy of Example 4 was replaced with Fe, and the Cu alloy of Example 8 was able to be absolutely constant for each TCR on the intermediate temperature side and the high temperature side. The value of the value does not change slightly, and the volume resistivity is further reduced. In the Cu alloy, when the volume resistivity is lowered below the absolute value of each TCR on the intermediate temperature side and the high temperature side, it is preferable to contain Si instead of Fe. In this case, it is considered that in the case of the Cu alloy, when Si is substituted for Fe, the intermediate temperature side and the high temperature side can be reduced. The absolute value of TCR has a tendency to reduce the volume resistivity.

Further, from the results of Examples 2 and 4, the case where the Cu alloy contains 1.50% by mass of Si (in the case of Example 4) and the case where the Cu alloy contains 0.50% by mass of Si (Example) 2) The volume resistivity of the Cu alloy becomes large. From this phenomenon, it was confirmed that the volume resistivity was lowered by lowering the Si content in the Cu alloy.

On the other hand, in Examples 1 to 16 and Comparative Examples 1 and 2, it was confirmed that there was no significant difference depending on the presence or absence of Ni and the Ni content of 0.30% by mass or less. In addition, since Ni has corrosion resistance, it can be considered to be advantageous for improving the corrosion resistance of the resistance material.

In addition, the embodiments and examples disclosed herein are merely illustrative and should not be construed as limiting. The scope of the present invention is defined by the scope of the claims and the scope of the invention, and all the modifications (variations) within the meaning and scope of the claims.

(industrial availability)

The resistive material of the present invention is suitable for use in a resistor comprising a temperature range exceeding 100 ° C, for example, a wide temperature range of 25 ° C to 150 ° C.

Claims (4)

A resistive material is composed of a Cu alloy containing Cu, 6.20% by mass or more and 7.40% by mass or less of Mn, and 0.15% by mass or more and 1.50% by mass or less of Si, and an absolute value of TCR at 25 ° C to 150 ° C. Below 15ppm/K. In the above-mentioned Cu alloy, the total amount of the Mn content and the Si content is 6.75 mass% or more and 8.40 mass% or less. The resistive material according to claim 1 or 2, wherein the TCR of -50 ° C to 25 ° C is 0 ppm / K or more and 50 ppm / K or less. The resistive material of claim 1 or 2, wherein the absolute value of TCR of 25 ° C to 60 ° C is 10 ppm / K or less.