JPH04231433A - Electrifying material - Google Patents

Abstract

PURPOSE:To obtain an electrifying material having high strength and high electric conductivity and excellent in migration resistance, thermal peeling resistance of plating, etc., by specifying a composition consisting of Ni, P, Fe, Cr, Mn, Mg, Co, and Cu. CONSTITUTION:The electrifying material can be obtained by providing a composition consisting of, by weight, 0.5-3.0% Ni, 0.05-1.0% P, 0.05-5.0% of one or more elements among Fe, Cr, Mn, Mg, and Co, and the balance Cu with inevitable impurities and further containing, if necessary, 0.1-3.0% Zn and/or 0.001-5.0% of one or more elements among Ti, Sn, Al, B, As, Sb, Ag, Pb, Be, and Zr as accessory components. This electrifying material has high strength and high electric conductivity and also has superior migration resistance, thermal peeling resistance of solder plating and tin plating, weldability, and hot rollability.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current-carrying material for electrical parts that suppresses migration between lead frames, terminals, connectors, and bus bars (also referred to as bus bars).

0002

2. Description of the Related Art In recent years, electronic and electrical equipment, etc. have become smaller and lighter, and the parts used, such as connectors, have become smaller and the distances between parts have also tended to become significantly shorter. or,
Circuits are becoming increasingly integrated. In other words, in the past, individual electronic components were connected by lead wires to form a circuit, but as the number of components increases, circuits become more complex, so circuits are becoming smaller by integrating them. There is.

0003

[Problems to be Solved by the Invention] In conventional miniaturized and integrated circuits, different circuits or wiring are separated by a small interval for miniaturization, but there is a problem that water, etc. When an electrolyte is present, an electrochemical reaction occurs, and copper ions dissolved from the copper alloy that is the material of the current-carrying part on the high-potential side are deposited on the low-potential side, and when the amount increases further, a short circuit occurs. This phenomenon is called migration, and when such migration occurs, the circuit no longer functions properly. Therefore, in recent years, there has been a strong desire for materials that have high electrical conductivity and do not cause migration.

[0004] Cu-Ni-P alloy is disclosed in Japanese Patent Application Laid-Open No. 1-242.
740 is an alloy that has excellent migration resistance, high strength, and high conductivity, and is suitable for conductive materials such as lead frames, terminals, connectors, and bus bars. As a result, cracks tend to occur during welding or hot rolling, and there are problems with manufacturability and heat-resistant peeling properties for solder plating, Sn plating, etc., and there are problems in using it for products that require plating.

[0005]

[Means for Solving the Problems] The present inventors have conducted research in view of the above problems, and have developed a method for adding Fe and C to Cu-Ni-P alloys.
By adding one or more of r, Mn, Mg, and Co, weldability and
It has been discovered that hot rolling properties and heat peeling properties of solder plating and Sn plating can be improved, and lead frames,
Ni can be used as a conductive material for terminals, connectors, bus bars, etc.
0.5-3.0wt%, P0.05-1.0wt% and F
containing 0.05 to 5.0 wt% of one or more of e, Cr, Mn, Mg, and Co, or Zn0.
1 to 3.0%, or further contains Ti, Sn, Al, B, As, Sb, Ag, P as subcomponents in both of the above.
It is characterized in that it contains one or more of the group consisting of Zr, Be, and Zr in a total amount of 0.001 to 5.0 wt%, and the balance consists of Cu and inevitable impurities.

According to the present invention, the amount of each element added to Cu is determined in consideration of the following. That is, first of all, Ni is an element that has the effect of suppressing the migration property of copper and copper alloys by being contained in copper and copper alloys.

Although the mechanism for suppressing the migration phenomenon is not clear, the presence of Ni reduces the elution amount of Cu ions, and the formation of Ni compounds obstructs the conduction of electricity through the deposited Cu particles. It is presumed that the migration phenomenon between them is suppressed.

[0008] The reason why Ni and P are contained at the same time is that Ni and P form a compound and precipitate into the copper and copper alloy, which improves the strength and dielectric constant compared to when Ni or P is contained alone. It is.

[0009] The reason for setting the Ni content to 0.5 to 3.0 wt% is that if the Ni content is less than 0.5 wt%, it will not be effective in suppressing the migration phenomenon, and if it exceeds 3.0 wt%, the migration phenomenon will not be suppressed. This is because although it is effective, the conductivity decreases, the amount of heat generated when electricity is applied increases, and the heat dissipation performance also decreases.

[0010] The reason why the P content is set to 0.05 to 1.0 wt% is that if the P content is less than 0.05 wt%, the effect of forming a compound with Ni and improving strength and conductivity is small;
This is because if it exceeds 1.0 wt%, the electrical conductivity decreases significantly, and the heat peelability, weldability, and hot rollability of solder plating and Sn plating decrease.

[0011] The reason why the Zn content is set to 0.1 to 3.0 wt% is that Zn promotes the effect of suppressing the Ni migration phenomenon by being co-added with Ni, and also improves the heat-resistant peeling property of Sn plating and solder plating. The purpose is to improve
This is because if the content is less than 0.1 wt%, the effect will be low, and if it exceeds 3.0 wt%, the conductivity will decrease significantly.

[0012] The reason why one or more of Fe, Cr, Mn, Mg, and Co is set at 0.05 to 5.0 wt% is as follows.
These elements have the effect of suppressing the migration phenomenon and easily form compounds with P, so Ni and P
It prevents the compounds from becoming coarse and improves weldability and hot rollability, and also reduces the amount of solid solution of P, contributing to improving the heat peeling properties of Sn plating and solder plating. However, the effect is low below 0.05wt%, and 5.0wt%
%, the conductivity will drop significantly.

Furthermore, Ti, Sn, Al,
1 from the group consisting of B, As, Sb, Ag, Be, Zr
The reason for including the species or two or more species in a total amount of 0.001 to 5.0 wt% is to improve the strength, but 0.001 w
This is because if it is less than t%, there is no effect, and if it exceeds 5.0wt%, the conductivity decreases.

[0014]

[Example] Specific examples of the present invention are shown below.

First, the alloy of the present invention having the composition shown in Table 1 was melted and cast in the air or an inert atmosphere, and hot rolled after facing.
After that, cooling rolling, annealing and pickling were repeated, and comparative alloy No.
．． All specimens other than No. 11 and No. 12 were final annealed at 450° C. for 10 hours, pickled, and then cold-rolled at a workability of 20% to obtain a plate with a thickness of 0.8 mm. Then, the surface was polished with #1200 emery paper. In addition, comparative alloy No. For Nos. 11 and 12, commercially available tough pitch copper and one type of brass were used, respectively.

[0016]

[Table 1] The test materials thus obtained were evaluated for tensile strength, elongation, electrical conductivity, heat peeling resistance of Sn plating and solder plating, weldability, and migration resistance. The results are shown in Table 2. In addition, hot rolling properties were investigated using ingots that had been melted and cast and then face-milled.

[0017] The heat-resistant peeling property of Sn plating was determined by heating a 10 mm x 50 mm strip test piece of Sn plating on a copper base plating for a predetermined time at 150°C, and then bending it back and forth by 90° once. The time required for the plating to peel off was measured.

[0018] Heat-resistant peelability of solder plating is 90% Sn10
A 10 mm x 50 mm strip test piece coated with % Pb gloss solder was heated in the air at 150° C. for a predetermined time, then bent 90° back and forth once, and the time it took for the plating to peel off at the bent portion was measured.

Weldability was determined by making a weld bead with a length of 100 mm in the center of a 80 mm x 200 mm specimen by inert gas arc welding, and then observing the presence or absence of cracks using a 5x magnifying glass. Migration resistance test material was 10mm x 10
The test material was cut to 0 mm and set as a set of two pieces as shown in Figure 1, and then soaked in tap water (30 mm) as shown in Figure 2.
0cc). Next, apply 14V to these two test materials.
A direct current voltage of 200 mL was applied, and the change in current value with respect to elapsed time was measured using a recorder. A representative example of this result is shown in FIG. Further, Table 2 shows the time required for the current value to reach 1.0 A (arrow in FIG. 3) for each sample material.

[0020]

[Table 2] Hot rolling property was determined by heating an ingot of each test material at 800° C. for a certain period of time, then hot rolling from a plate thickness of 25 mm to 8 mm, and visually observing the presence or absence of cracks.

From Table 2, alloys Nos. 1 to 6 of the present invention all have electrical conductivity of 57% IACS or higher, and are excellent in strength, heat peeling resistance of Sn plating and solder plating, and migration resistance, and are suitable for use in lead frames, automobile terminals, This alloy is ideal for electrically conductive materials that require migration resistance, such as connectors and bus bars. Furthermore, it has good weldability, hot rolling properties, and excellent manufacturability.

[0022] Also, the alloy No. of the present invention. By containing Zn from 2 and 3, the heat peeling resistance and migration resistance of Sn plating and solder plating are further improved.

Comparative alloy No. 7, 8, and 13 are alloy Nos. 7, 8, and 13 of the present invention. Compared to 2, 4, and 5, it does not contain Cr, Mn, Mg, Co, and Fe, so the heat peeling resistance of Sn plating and solder plating is poor, and the weldability and hot rolling property are poor, and the migration resistance is also poor. It is declining. Comparative alloy No.
Since No. 9 does not contain P, Ni does not precipitate as a compound with P, and the strength and conductivity are low. Comparative alloy No. 10 is N
Since the content of i and P is too large, the conductivity is low, and the heat-resistant peelability, weldability, and hot rollability of Sn plating and solder plating are poor. Comparative alloy No. Although No. 11 is tough pitch copper, its strength is low and its migration resistance is poor. No. No. 12 is a type of brass conventionally used for automobile bus bars, etc., and has high migration resistance but low electrical conductivity.

[0024]

[Effect of the invention] The current-carrying material of the present invention has high electrical conductivity,
Moreover, it is a material with excellent migration resistance, heat peeling resistance of plating, weldability, and hot rollability.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a sample material for a migration resistance test.

FIG. 2 is an explanatory diagram of the test.

FIG. 3 is a graph showing migration resistance test results.

Claims (4)

[Claims] [Claim 1] Ni0.5-3.0wt%, P0.0
5 to 1.0 wt% and 0.05 to 5.0 wt% of one or more of Fe, Cr, Mn, Mg, and Co, with the balance consisting of Cu and inevitable impurities. . [Claim 2] Ni0.5-3.0wt%, P0.0
5 to 1.0 wt%, and 0.05 to 5.0 wt% of one or more of Fe, Cr, Mn, Mg, and Co, and further subcomponents of Ti, Sn, Al, B, As, Sb,
1. A current-carrying material characterized in that it contains one or more of the group consisting of Ag, Pb, Be, and Zr in a total amount of 0.001 to 5.0 wt%, with the balance consisting of Cu and inevitable impurities. [Claim 3] Ni0.5-3.0wt%, P0.0
5 to 1.0 wt%, Zn0.1 to 3.0 wt%, and Fe
, Cr, Mn, Mg, and Co.
．． A current-carrying material characterized in that it contains 05 to 5.0 wt% of Cu, and the remainder consists of Cu and unavoidable impurities. [Claim 4] Ni0.5-3.0wt%, P0.0
5 to 1.0 wt%, Zn0.1 to 3.0 wt%, and Fe
, Cr, Mn, Mg, and Co.
．． 05 to 5.0 wt%, and further contains Ti and Sn as subcomponents.
, Al, B, As, Sb, Ag, Pb, Be, and Zr in a total amount of 0.001 to 5.
A current-carrying material characterized by containing 0 wt% of Cu and the remainder consisting of Cu and unavoidable impurities.