JPH0432529A - Copper alloy having low constant mass temperature coefficient of electric resistance - Google Patents

Abstract

PURPOSE:To obtain a copper alloy having a low constant mass temp. coefficient of electric resistance by incorporating each specified compsn. of Ni and Si into copper. CONSTITUTION:This copper alloy contains, by weight, 0.50 to 0.75% Ni, 0.10 to 0.16% Si and the balance Cu. In this copper alloy, the certain mass temp. coefficient of electric resistance is low, and the variation of resistance value caused by the change of environmental temp. is moreover low. Thus, at the time of using the copper alloy as the structural material for the electric circuit of automobiles, electronic equipment used in an environment high in the change of temp., the malfunction of the equipment can be suppressed, and the reliability on the equipment can be improved. In the above compsn., Ni and Si reduce the constant mass temp. coefficient in the electric resistance of the copper alloy as well as improve its strength, but in the case their content is less than the lower limit, the above effects are made insufficient. Furthermore, in the case their content exceeds the upper limit, its electric conductivity is reduced to >=35% IACS as well as its cold workability is damaged.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is directed to a material having a constant mass temperature coefficient of electrical resistance that is suitable as a current-carrying material for electric circuits incorporated in automobiles and electronic devices used in environments with severe temperature changes. Concerning small copper alloys.

[Prior Art] Conventionally, oxygen-free copper, phosphorus-deoxidized copper, or the like has been generally used as a current-carrying material in electric circuits incorporated in automobiles, electronic equipment, electrical equipment, and the like.

[Problems to be Solved by the Invention] However, the above-mentioned oxygen-free copper and phosphorus-deoxidized copper have a drawback that the constant mass temperature coefficient of electrical resistance is large. For this reason, in cases where the temperature fluctuates significantly, such as in automobiles or electronic devices used in environments with rapid temperature changes, the electrical resistance of the electrical circuits built into them tends to fluctuate, causing damage to the circuit. The drawback is that the voltage and current are difficult to stabilize. As a result, the characteristics of current-carrying materials have become a factor that reduces the reliability of electrical circuits, such as equipment malfunctioning. Further, in order to avoid such inconveniences, a control circuit can be provided and the operation of the electric circuit can be stabilized by this control circuit, but this has the disadvantage that the circuit becomes complicated.

The present invention has been made in view of such problems, and includes:
The constant mass temperature coefficient of electrical resistance is small, so there is little variation in resistance value due to changes in environmental temperature, which can improve the reliability of electrical circuits built into electronic devices, etc. The mud mass temperature coefficient of electrical resistance is small. The purpose is to provide copper alloys.

[Means for Solving the Problems] The copper alloy having a small mud mass temperature coefficient of electrical resistance according to the present invention contains 0.50 to 0.75% by weight of Ni and 0.10 to 0.16% by weight of Si. The remainder consists of Cu and inevitable impurities.

In this case, in addition to the Ni and Si, O, IO to 1
．． It may contain 0% by weight of Zn.

[Function] Hereinafter, the reason for adding a component of a copper alloy having a small mud mass temperature coefficient of electrical resistance and the reason for limiting the composition according to the present invention will be explained.

Roof 1 Ni forms a solid solution in steel together with Si, which will be described later, and has the effect of lowering the mud mass temperature coefficient of electrical resistance in the copper alloy and improving the strength of the copper alloy. However, when the Ni content is less than 0.50% by weight, the above effects are insufficient. Further, when the Ni content exceeds 0.75% by weight, the electrical conductivity decreases to 35% IAC5 (when the electrical conductivity of pure copper annealed material is 100) or less, and cold-opening workability is also impaired.

Therefore, the Ni content is 0.50 to 0.75% by weight.

As mentioned above, L Si forms a solid solution in steel together with N r and has the effect of lowering the mud mass temperature coefficient of electrical resistance in copper alloys and improving the strength of copper alloys. However, when the Si content is less than 0.10M1k%, the above effects are insufficient. In addition, the Si content is 0.16
When it exceeds % by weight, the electrical conductivity decreases to 35%lAC3 or less, and cold workability (particularly workability during pipe manufacturing) is inhibited. Therefore, the NSISi content, IO ~ 0.16
Weight%.

Z'' - Zn has the effect of improving solder adhesion when soldering electronic components, etc. to the wiring paths of an electric circuit formed of a copper alloy. For this reason, Zn may be included in the copper alloy containing Ni and Si. However, if the Zn content is less than 0.10% by weight, the above effects cannot be obtained.

Furthermore, if the Znn content exceeds 0% by weight, not only the double effect is saturated and is wasted, but also the electrical conductivity decreases significantly. Therefore, when containing Zn, the content is set to 0.10 to 1.0% by weight.

In addition, the copper alloy with a small mud mass temperature coefficient of electrical resistance according to the present invention is not applicable as a current-carrying material such as an electric circuit incorporated in an electric component or an electronic component, or a wiring material connecting each component. It can also be applied as a shielding material against magnetic or electric fields.

In addition, the copper alloy according to the present invention may be used in an electric circuit in any shape such as a coil shape, a tube, a rod, a wire, a plate, a strip, and a foil, in addition to leads etc., and there are limitations depending on the shape. It is not something that will be done.

Examples] Next, examples of the present invention will be described in comparison with comparative examples that fall outside the scope of the claims.

First, a copper alloy having the composition shown in Table 1 below was melted by atmospheric melting, and then an ingot having a thickness of 50 mm, a width of 85 mm, and a length of 200 mm was produced. After heating these ingots to 900° C., they were hot-rolled to a thickness of 5 mm to obtain hot-rolled materials.

However, Comparative Examples 1 and 2 are pure copper and phosphorus-deoxidized copper with a purity of 99.99% by weight, respectively, and both are conventionally used as materials for electric circuits.

Table 1 Next, these hot rolled materials were mixed with sulfuric acid water (concentration 20% by volume).
) to remove surface oxides, cold rolling was performed to obtain a plate with a thickness of 1 mm.

Then, this plate material was heated to a temperature of 600°C for 1 hour,
Thereafter, it was water-cooled at a cooling rate of 15° C./second or more.

Next, this plate material was pickled with the sulfuric acid water, and then cold-rolled to a thickness of 0.5 mm.

The electrical conductivity of each of the thus obtained rolled materials of Examples and Comparative Examples was measured by a four-probe method based on JIS H0505. The sample temperatures at this time were 0°C, 540°C, 160°C, and 80°C. The results are shown in Table 2 below.

Table 2 As is clear from this Table 2, Example 1 according to the present invention
In all of 5 to 5, the constant mass temperature coefficient of electrical resistance is about 1/2 to that of Comparative Example II 2! /3 is low. Therefore, the alloys of Examples 1 to 5 have little variation in electrical resistance with respect to temperature changes, and are therefore suitable as materials for electrical circuits of devices used in environments with severe temperature changes.

[Effects of the Invention] As explained above, according to the present invention, Ni and Si are contained in predetermined compositions, and Zn is further added in a predetermined content as necessary, so that the constant mass temperature of electrical resistance A copper alloy with a small coefficient can be obtained. When this copper alloy is used as an electric circuit constituent material for automobiles and electronic devices used in environments with large temperature changes, malfunctions of the devices can be suppressed and the reliability of the devices can be improved. Therefore, the copper alloy according to the present invention is extremely useful as a constituent material of electric circuits incorporated in, for example, electronic devices installed in automobiles and electronic devices used in environments with severe temperature changes.

Claims (2)

[Claims] (1) 0.50 to 0.75% by weight of Ni and 0.10% by weight
A copper alloy having a small constant mass temperature coefficient of electrical resistance, characterized in that it contains 0.16% by weight of Si, and the remainder consists of Cu and unavoidable impurities. (2) The copper alloy having a small constant mass temperature coefficient of electrical resistance according to claim 1, characterized in that it contains 0.10 to 1.0% by weight of Zn.