JPS6289520A - Manufacture of terminal lead wire for electronic equipment - Google Patents

Abstract

PURPOSE:To obtain a lead wire excellent in bending strength, mechanical strength, electric conductivity, etc., by cold wire drawing a rough drawn wire of copper alloy, after annealing perfectly, by performing the cold wire drawing with specific reduction in area. CONSTITUTION:The rough drawn wire of copper alloy is manufactured, annealed after continuous wire drawing, then performed the cold wire drawing by dies with the reduction in area of 2-30%. In this way, the terminal lead wire for the electronic equipment excellent in mechanical properties for a compression molding of its one end and annealing received on the manufacturing processes for those element parts is obtained.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is directed to a terminal lead wire used for resistors, capacitors, silicon or germanium semiconductor devices, etc., which is exposed to one end of the lead wire during the manufacturing process of those device components. The present invention relates to a method for manufacturing a terminal lead wire for electronic device parts that maintains excellent mechanical properties even when subjected to compression molding and heat treatment.

(Prior Art) Pure copper wire and heat-resistant copper alloy wire are often used for terminal lead wires of electronic device parts. These lead wires are used as terminal lead wires for components, so one end of the lead wire is compression molded (hereinafter referred to as header processing) and then cut into a fixed length using high-speed automated equipment for mass production.

Therefore, if the wire is hard, it becomes difficult to process the header, and cracks occur in the molded part, causing problems in the mass production process. Therefore, the wire is tempered to be semi-hard.

Further, during the manufacturing process of electronic device parts, when the lead wires are attached to the element parts, or after being attached, the lead wires are subjected to various prenatal heat treatments and unavoidable bending stress, so that the lead wires are softened and bent.

For example, lead wires used in resistors and capacitors undergo heat treatment at about 250°C during manufacturing processes such as brazing, molding, painting, and stabilization.

Further, in the case of semiconductor devices, the soldered joints between the device parts and the terminal lead wires are heat treated at 3°00 to 400° C. for about 10 minutes, and then the soldered portions are molded with a synthetic resin material.

In particular, when the lead wire is made of pure copper, it has high electrical conductivity and thermal conductivity, but heat treatment at around 200°C recrystallizes and softens the bending strength, reducing the bending strength, making it difficult to move the element parts to the next process. The lead wire is bent during the next barrel plating process, which involves plating inside or onto the copper wire. Therefore, pure copper wire is not used when undergoing high temperature heat treatment.

Automated mass production methods are used to manufacture these electronic device parts, so if the terminal lead wire becomes soft and bent, it is no longer acceptable to manually sort out or correct the bend, which will interfere with automation. This also causes trouble when mounting element parts on a printed circuit board.

For this reason, heat-resistant copper alloy wires such as Cu-Ag and Cu-5n are used as lead wires that undergo high-temperature heat treatment. After cold wire drawing, the alloy wire is subjected to continuous softening or batch softening to improve the hardness of the wire, but the reliability of the bending strength after high-temperature heat treatment has not yet been resolved. However, there are still problems in using it for automation.

(Problems to be Solved by the Invention) As a result of various studies conducted by the present inventors as to what kind of characteristics a lead wire should have to solve the problems, We found that the following characteristics should be solved. In other words, (1) the header has good workability, (2) it has heat resistance to process heat treatment (400°C x 10 minutes), and (3) it has electrical conductivity of 95% or more and has good heat dissipation properties. Good conductivity (4) Strong bending resistance against bending stress Regarding these required characteristics (2) and (3), it is preferable to use a heat-resistant and highly conductive copper alloy, and the alloy composition should not contain Cu. As a base material, 8g+sn+IIl+Pb, Bi, C
r, Co, Ni+Fe, Zy, Se, Te, If, B
A copper alloy in which one or more of elements such as , Ti, and P is added in an amount of 0.02 to 0.2 wt% relative to Cu is selected.

Regarding (1) and (4), the hardness of the wire rod must be accurately tempered.

For example, for a 0.8mmφ copper alloy wire, the bending strength before heat treatment is 150 to 370g-cm, and the heat treatment (400℃
The bending strength after 10 minutes is preferably 140 to 320 g-cm.

0, 6mmφ copper alloy wire has a bending strength of 8 before heat treatment.
The bending strength after heat treatment (400° C. x 10 minutes) is preferably 75 to 165 g-cm.

If the value of these required properties is below the lower limit, the wire will be bent during the manufacturing process of the element parts, causing problems in automated production, and if the value is above the upper limit, the wire will be hard, causing problems in header workability. Furthermore, when the terminal lead wires of the element parts are mounted on the printed circuit board and fixed by bending, the molded part of the element parts may be destroyed, which is not preferable.

(Means for Solving the Invention) The present invention has been made to satisfy the above-mentioned required characteristics.
A method for manufacturing a terminal lead wire for electronic device parts, which comprises cold drawing a copper alloy rough drawn wire, and then cold drawing the wire to a completely annealed surface area ratio in the range of 2 to 30%. be.

The reason why the area reduction rate is set to 2 to 30% in the above is that if it is less than 2%, the wire will not be hardened and will bend easily, and if it exceeds 30%, the wire will become hard and the header workability will be poor, and the element parts This is not preferable because the molded part of the element component will be destroyed when it is mounted on a printed circuit board and fixed by bending. A suitable area reduction is between 3 and 15%.

Next, three types of heat-resistant, highly conductive copper alloy wires were manufactured, and the examples of the present invention, comparative examples, and conventional examples were compared to examine how the characteristics of the copper alloy wires changed before and after heat treatment. The results are shown in Table 1.

For conventional examples Nos. 19 to 27, copper alloy 8m1IIφ
0.8 mmφ by manufacturing rough drawn wire and continuous drawing softening at room temperature to have a bending strength in the range of 170 to 230 g cm.
Finished with wire rod. After heat-treating the wire at 400°C for 10 minutes, we investigated its bending strength, tensile strength, and conductivity. As a result, the bending strength suddenly decreased, and the value was in the range of 100 to 110 g cm. It can be seen that the required characteristics are not met.

For Examples Nos. 1 to 12 and Comparative Examples Nos. 13 to 18, copper alloy rough drawn wires of 8 mmφ were manufactured, and after continuous wire drawing, annealing treatment was performed at 400° C. for 1 hour. Cold wire drawing was performed with the area reduction ratio shown in the comparative example.
Finished into a wire rod with a diameter of 8 mm. As a result of conducting a characteristic investigation on the bending strength, tensile strength, electrical conductivity, and the presence or absence of a crank in the compression molded part during heso-goo processing after heat-treating the wire at 400°C for 10 minutes, Examples Nos. 1 to 12 were obtained.
has appropriate bending strength, tensile strength, and conductivity even when subjected to high-temperature heat treatment, and all values that satisfy the required properties can be obtained.

When comparative example No. 13.15.17 was heat-treated by wire drawing with an area reduction rate of 1%, the bending strength was 100 to 110 g.
clll range and does not meet the required characteristics. Furthermore, when comparative example No. 14.16.18 was tempered by wire drawing with an area reduction rate of 35%, the bending strength value was 330 to 350 g-Cm.
It can be seen that the required characteristics are not met.

(Example) Example 1゜A rough drawn wire of 81φ made of Cu-0.1%Ag alloy was manufactured.
, after continuous wire drawing to 82mmφ, 400℃, 1
0.8mmφ with time annealing treatment and area reduction rate of 5%
The bending strength was reduced to 1 by performing cold wire drawing using a die.
It was tempered into a wire rod designated as 808-cIII. 40 pieces of the wire
As a result of heat treatment at 0° C. for 10 minutes and measurement of bending strength, a value of 170 g-cn+ was obtained.

Example 2 A rough drawn wire of 8 mmφ of Cu-0.05% Sn alloy was manufactured, and after continuous wire drawing to 0.84 mm+φ, the wire was heated at 400°C.
, 0,8 which is annealed for 1 hour and has an area reduction rate of 10%.
Cold wire drawing was performed using a mmφ die, and the wire rod was tempered to have a bending strength of 215 g-cm. As a result of heat-treating the 8-wire wire at 400° C. for 10 minutes and measuring its bending strength, a value of 203 g-Cm0 was obtained.

Example 3 A rough drawn wire of Cu-0.13% In alloy with a diameter of 8 mm was produced, and the wire was continuously drawn to a diameter of 0.89 mm, and then continuously softened and cooled to give an area reduction rate of 20%. Cold wire drawing is performed through a die of mmφ, and the bending strength is increased to 27 mm.
The wire rod was tempered to a thickness of 5 g-cm. The wire rod is heated to 400℃
As a result of measuring the bending strength after heat treatment for 10 minutes, 2
A value of 57 g-cm was obtained.

Example 4 A rough drawn wire of Cu-0,13%In alloy with a diameter of 8 mm was manufactured, and after continuous wire drawing to 0.633 mmφ, the wire was heated at 400°C.
, 0,6, which is annealed for 1 hour and has an area reduction rate of 10%.
A cold wire drawing process was performed using a mmφ die, and the wire rod was tempered to have a bending strength of 115 g-clll. The wire rod was subjected to heat treatment at 400° C. for 10 minutes and the bending strength was measured, and as a result, a value of 108 g-cm was obtained.

(Effects of the Invention) The lead wire manufactured by the present invention not only has excellent reliability in bending strength against high-temperature heat treatment, but also has excellent mechanical strength, electrical conductivity, thermal conductivity, and header processability. Because it is easy and inexpensive to manufacture, it is extremely effective as terminal lead wires for electronic device parts such as silicon or germanium semiconductors, resistors, capacitors, switches, connectors, and coil parts that use automated production methods. It is something.

Agent: Patent Attorney Takashi Mizuguchi - Procedural amendment (voluntary) November 7, 1985

Claims (1)

[Claims] A method for manufacturing a terminal lead wire for electronic device parts, which comprises completely annealing a copper alloy wire and then cold drawing the wire at an area reduction of 2 to 30%.