JP3413864B2 - Connector for electrical and electronic equipment made of Cu alloy - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Cu alloy connector for electric and electronic equipment which is excellent in solderability and is resistant to discoloration of Sn plating under a high temperature environment.

[0002]

2. Description of the Related Art Conventionally, a Cu alloy connector for electric and electronic equipment, in% by weight (hereinafter,% means% by weight), Zn: 0.1 to 3%, Ni: 0.5 to 3%, Si : 0.08 to 0.8%, Sn: 0.1 to 0.9%, Fe: 0.007 to 0.25%, P: 0.001 to 0.2%, and the balance Cu Also known is a Cu alloy connector for electric and electronic equipment, which is composed of a Cu alloy having a composition of unavoidable impurities (see Japanese Patent Laid-Open No. 3-56636).

[0003]

However, the above-mentioned conventional Cu alloy connector for electric and electronic equipment has Zn: 0.
Since it is composed of a Cu alloy with a low Zn content of 1 to 3%, (1) even if Sn plating is applied to the surface, it will discolor when exposed to a high temperature environment, increasing contact resistance, In order to prevent this, it is necessary to use a Cu alloy containing Zn in excess of 3%. However, a Cu alloy containing Zn in excess of 3% has poor solderability. The solderability of Cu alloy electrical and electronic equipment connectors containing more than 2 parts will be impaired. (2) When the connector is manufactured by punching, especially high-speed punching, the die wear is severe and the die life is long. There are problems such as shortening and frequent maintenance and replacement of molds, which increases the manufacturing cost.

[0004]

Therefore, the present inventors have
As a result of research to solve this problem, Zn was 3%
Even if it is a Cu alloy containing more than 0.005%, Mg: 0.00
1 to 0.2% is added, and if necessary, Pb: 0.
When a connector is made of a Cu alloy added with 001 to 0.01%, it does not impair the solderability as found in conventional connectors, and the Sn plating discolors even when exposed to a high temperature environment and the contact resistance Therefore, it was found that the wear of the mold can be reduced during high-speed punching.

The present invention has been made on the basis of such findings, and (a) by weight, Zn: more than 3 to 35%, Ni: 0.1 to 3%, Si: 0.02 to 1 %, Sn: 0.01 to 0.9%, Fe: 0.007 to 0.25%, P: 0.001 to 0.2%, Mg: 0.001 to 0.2%, the rest being Cu and A Cu alloy connector for electric and electronic equipment, which is composed of a Cu alloy having a composition of inevitable impurities, (b) in wt%, Zn: more than 3 to 35%, Ni: 0.1 to 3%, Si: 0.02 ~ 1%, Sn: 0.1 to 0.9%, Fe: 0.007 to 0.25%, P: 0.001 to 0.2%, Mg: 0.001 to 0.2%, Pb: C having a composition of 0.001 to 0.01% and the balance of Cu and unavoidable impurities
Cu alloy electrical and electronic equipment connector composed of u alloy,
It is characterized by

Next, the reason why the composition of the Cu alloy used for manufacturing the connector for electric and electronic equipment of the present invention is limited as described above will be explained.

(A) Zn If Zn is added in excess of 3%, it has a function of preventing discoloration of Sn plating in a high temperature environment and suppressing an increase in contact resistance, but impairs solderability. However, Mg: 0.00
The addition of 1 to 0.2% does not impair the solderability.

On the other hand, when Zn is added in an amount exceeding 35%,
Cold workability deteriorates and ear cracking occurs, resulting in insufficient reliability as a connector material. Therefore, the Zn content is set to more than 3% to 35%.

(B) Ni and Si Both of these components are partially solid-dissolved in the base material, but most of them are bonded to each other to form a compound, which further improves the strength without significantly impairing the conductivity. In addition to increasing the softening temperature and improving the thermal creep characteristics, their contents are Ni: less than 0.1% and Si:
If it is less than 0.02%, the desired improving effect on the above-mentioned action cannot be obtained, while the contents are Ni: 3% and S, respectively.
If i exceeds 1%, the hot rolling property and the heating adhesion of the plating will be deteriorated. Therefore, the content of Ni should be 0.1 to 3% and Si should be 0.02 to 1%. Specified.

(C) Sn The Sn component has a function of forming a solid solution in the base material to further improve the strength, spring property and bending workability, but if its content is less than 0.01%, it is desirable for the above function. No effect,
On the other hand, if the content exceeds 0.9%, the electrical conductivity will decrease, so the content should be 0.01-0.9%.
Stipulated in.

(D) Fe The Fe component has the effect of enhancing the reliability of terminals and connectors through the effect of refining the compound precipitation of Ni and Si, and thereby improving the strength and the plating heating adhesion.
If the content is less than 0.007%, the desired effect cannot be obtained, while if the content exceeds 0.25%, the hot rolling property is deteriorated. The amount was set to 0.007 to 0.25%.

(E) The P P component has the effect of suppressing the deterioration of the spring property caused by bending and thus improving the holding force of the terminals and connectors that have been formed, but its content is less than 0. 001%
If the content is less than 0.2%, the desired effect cannot be obtained. On the other hand, if the content exceeds 0.2%, the hot rolling property is deteriorated and
Since the plating heating adhesion is impaired, the content thereof is set to 0.001 to 0.2%.

(F) Mg This component suppresses hot rolling cracks due to solidification strain, which is promoted by upsizing of the ingot, and deviation of S and other impurity elements, and improves punching workability. It has the effect of improving the die wear property and further improving the solderability by coexisting with Zn in excess of 3%, but if the content is less than 0.001%, the desired effect cannot be obtained in the above action. On the other hand, if Mg exceeds 0.2%, the oxides are likely to be involved and casting defects increase, and hot rolling cracks occur when hot-rolling the ingot having the casting defects. Moreover, the conductivity is impaired, which is not preferable. Therefore, the content of Mg is set to 0.001 to 0.2%.

(G) Pb Pb is a component that improves punching workability, but if its content is less than 0.001%, the desired effect cannot be obtained.
On the other hand, if the content is more than 0.01%, cracks are likely to occur during hot rolling and the number of slit-removed portions is increased, which is not preferable. Therefore, the Pb content is 0.001 to 0.
It was set at 01%.

[0015]

[Example] Using a normal low-frequency groove type melting furnace, under the atmosphere and under the charcoal coating, C of the component composition shown in Tables 1 and 2 respectively.
U alloy is melted and semi-continuous casting method, thickness: 160m
An ingot having dimensions of m, width: 450 mm, length: 2400 mm was prepared, and then this ingot was hot-rolled at a predetermined temperature within the range of 750 to 950 ° C. to obtain a thickness of 10 mm. A hot-rolled sheet was used, and after water cooling, both upper and lower surfaces were chamfered by 0.5 mm each.
During this chamfering, visually observing the number of side edge cracks of 5 mm or more and the maximum side edge crack length over the entire length of the hot-rolled sheet,
The results are shown in Tables 3 to 4, and the hot rolling property was evaluated.

The hot-rolled sheet having the above-mentioned maximum side edge crack is slit by removing the side edge so as to eliminate the maximum side edge crack, and the hot-rolled sheet in which the side edge crack cannot be visually detected is also safe. After chamfering each side by 3 mm, the cold rolling and annealing are repeated under normal conditions, and 75% finish rolling is performed to form a strip with a thickness of 0.3 mm. ~
The present invention Cu alloy connector material (hereinafter referred to as the present invention connector material) 1 to 11 and the comparative Cu alloy connector material (hereinafter referred to as the comparison) by annealing at a predetermined temperature within a range of 500 ° C. for 1 hour. Connector material) 1
6 and a conventional Cu alloy connector material (hereinafter referred to as a conventional connector material) were produced.

All the comparative connector materials have a composition in which any one of the constituent components is out of the range of the present invention.
It is shown with a mark.

The connector materials 1 to 11 of the present invention, the comparative connector materials 1 to 6 and the conventional connector materials thus obtained were subjected to the following tests to obtain solderability,
The mold wear resistance and the heat discoloration resistance of Sn plating were examined, and these results are shown in Tables 3 to 4.

(1) Solderability test A test piece having dimensions of thickness: 0.3 mm, width: 15 mm, length: 80 mm was degreased with acetone and pickled with 10% sulfuric acid,
Wash with water, dry, treat with rosin flux, temperature: 230
40mm in 60% Sn-40% Pb alloy solder bath at ℃
It was dipped at the depth for 5 seconds and pulled up. In this case, the solder wetted area of 95% or more was evaluated as "good" solderability, and less than 95% was evaluated as "bad" solderability.

(2) Die abrasion test by punching process Using a commercially available die made of WC-based cemented carbide (Co: 16% content), a circular hole with a diameter of 2 mm was punched into each of the above-mentioned strips for 1 million. Drilling, in this case, the hole diameter formed in the strip becomes smaller as the mold wears, so the change amount of the first hole diameter and the last hole diameter is divided by 1 million to obtain the average change rate, Of the obtained average change rates, the average change rate of the conventional Cu alloy strip was set to 1, and the relative ratio to this was calculated and evaluated. Therefore, it is indicated that the smaller the average rate of change is, the more the strip does not wear the die.

(3) Discoloration test by heating Sn plating and adhesion test Using the above various strips, thickness: 0.30 mm, width: 50 mm,
A test piece having a length of 100 mm was prepared and Sn-plated to a thickness of 2 μm by an ordinary electroplating method. The Sn-plated test piece was subjected to 200 ° C. at 160 ° C.
After heating for a time, visually observing the presence or absence of black discoloration after heating,
The heat discoloration resistance of Sn plating was examined.

Width: 1 from each test piece after the above heating
Cut out a test piece with dimensions of 5 mm and length: 80 mm,
Bending them by 180 ° and then bending them back again by 180 ° was performed, and the presence or absence of plating peeling at the 180 ° bent portions was observed. The results are shown in Tables 3 to 4, and S
The heat adhesion of n-plating was evaluated.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

[0027]

From the results shown in Tables 1 to 4, it is said that if Zn is added in an amount exceeding 3% in the conventional connector material, the solderability is deteriorated. However, if Zn exceeds 3%, it is contained. However, the connector materials 1 to 11 of the present invention containing Mg: 0.001 to 0.2% do not deteriorate in solderability, and the addition of Mg improves hot workability to form a plate material with good yield. It can be manufactured, and it can be seen that the Sn plating of the connector manufactured using this connector material does not discolor black even in a high temperature environment.

On the other hand, the comparative connector materials 1 to 6 and the conventional connector materials having compositions deviating from the conditions of the present invention produced cracks during hot rolling, poor solderability, and Sn-plated black at high temperature. From the fact that discoloration, peeling, increased die wear during punching, and at least one other undesirable property shown in the remarks column, connectors were produced using these comparative connector materials 1 to 6 and conventional connector materials. However, it turns out that a reliable connector cannot be obtained.

The tensile strength and elongation of the connector materials 1 to 11 of the present invention, the comparative connector materials 1 to 6 and the conventional connector material were measured. Since the tensile strength and the elongation were almost the same as those of the conventional connector material, the description in Tables 3 to 4 was omitted.

As described above, it is possible to provide a connector for electric / electronic equipment in which solderability is not impaired even if Zn is added in excess of 3% to prevent discoloration of Sn plating under high temperature. , Can greatly contribute to the development of the electric and electronic industries.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-4-224645 (JP, A) JP-A-2-118037 (JP, A) JP-A-2-170953 (JP, A) JP-A-2- 163331 (JP, A) JP-A 2-141562 (JP, A) JP-A 2-122039 (JP, A) JP-A 63-26320 (JP, A) JP-A 3-56636 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C22C 9/04 H01H 1/02 H01R 13/03

Claims (2)

(57) [Claims] 1. By weight%, Zn: more than 3 to 35%, Ni: 0.1 to 3%, Si: 0.02 to 1%, Sn: 0.01 to 0.9%, Fe: 0. 007 to 0.25%, P: 0.001 to 0.2%, Mg: 0.001 to 0.2%, and the balance being a Cu alloy having a composition of Cu and inevitable impurities. Cu alloy connector for electrical and electronic equipment. 2. By weight%, Zn: more than 3 to 35%, Ni: 0.1 to 3%, Si: 0.02 to 1%, Sn: 0.1 to 0.9%, Fe: 0. 007 to 0.25%, P: 0.001 to 0.2%, Mg: 0.001 to 0.2%, Pb: 0.001 to 0.01%, and the balance of Cu and inevitable impurities. Have C
A connector for electric and electronic equipment made of Cu alloy, which is made of u alloy.