JPH0266131A - High-strength and high-conductivity copper-base alloy - Google Patents

Abstract

PURPOSE:To improve the strength, elasticity and electric conductivity of the title alloy and providing it with excellent press formability and stress relaxation resistance by specifying the content of Ni, Be and Sn in a Cu alloy. CONSTITUTION:The compsn. of a Cu alloy is formed with, by weight, 0.1 to 3.0% Ni, 0.005 to 0.5% Be, 0.1 to 3.0% Sn and the balance Cu with inevitable impurities. If required, 0.01 to 5.0% Zn and total 0.005 to 1.0% of one or more kinds among Ti, Cr, Zr, Mg, Fe, Co, Si, Al, P and B are furthermore incorporated thereto. The alloy has high strength and high electric conductivity and is suitable as the material for a terminal of a wire harness. The alloy can therefore be correspond to the miniaturization and lightening of electric apparatus for an automobile and the densification of wiring.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a high-strength, high-conductivity copper-based alloy suitable as a terminal material for wire harnesses used in electrical components of automobile parts, etc.

(b) Prior art Today, as is well known, the automobile industry has come to play a major role as Japan's core industry, and the number of automobiles produced has increased significantly, and with the recent development of car electronics, Copper materials are becoming more and more popular.

Therefore, the wire harness, which plays a role in the electrical components of automobiles, is no exception, with a length of approximately IKm per vehicle and a weight of approximately 2
0Kg has reached the point where it is used.

However, the demands placed on cars these days are becoming increasingly strict, such as weight reduction, high reliability, and low cost.
Accordingly, wire harnesses are also required to be lighter in weight, more reliable, and lower in cost.

Here, a wire harness is a combination of electric wires and terminals, and in order to reduce weight and increase wiring density, it is necessary and essential to improve the material properties and reliability of the terminal material.

Under the above background, terminal materials are specifically made thinner and press-molded into complicated shapes, so they need to have good strength, elasticity, conductivity, and press-formability.

Furthermore, it not only has good corrosion resistance and stress corrosion cracking resistance, but also has excellent stress relaxation properties because thermal loads are applied around the engine room and exhaust gas system.

However, in the past, it has not been possible to obtain a material that has all of the above characteristics at the same time and is inexpensive.

(C) Disclosure of the Invention With the development of car electronics, the present invention provides a copper-based alloy that has the above-mentioned properties required for terminal materials for wire harnesses, more specifically, a copper-based alloy with a strength of 1.
It was developed as a result of intensive research to develop a copper-based alloy suitable as a terminal material for wire harnesses that has excellent elasticity and electrical conductivity, press formability, stress relaxation resistance, etc. The following copper-based alloys are provided.

That is, in the first invention, N i : 0.1 to 3.0
wt%, B e : 0.005-0.5 vt%, S
n: 0.1 to 3.0 wt%, the balance being Cu and unavoidable impurities, which is a high-strength, high-conductivity steel-based alloy.

The second invention is, Ni: 0.1 to 3.0 wt%,
Be: 0.005 to 0.5 wt%, Sn: 0.
1 to 3.0 wt%, Zn: Q, 01 to 5.0 wt%,
It is a high-strength, high-conductivity copper-based alloy with the remainder consisting of CuI2 and unavoidable impurities.

The third invention is Nt: 0.1 to 3.0 wt%,
Be: 0.005 to 0.5%, Sn:
0.1 to 3.0wt%, Zn: 0.01 to 5.0
wt%, and further includes Ti, CrZr, Mg, Fe, C
o, Si, A1. It is a high-strength, high-conductivity Ti4-based alloy containing one or more of P or B in a total content of 0.005 to 1.0 wt%, with the remainder being Cu and inevitable impurities.

The basic feature of the copper-based alloy according to the present invention is that by adding appropriate amounts of Ni, Be, and Sn, the copper-based alloy exhibits the above-mentioned properties necessary for a copper-based alloy suitable as a terminal material for wire harnesses. .

Next, the reason why the composition range of the copper-based alloy according to the present invention is limited as described above will be explained.

(1)NI Ni forms a compound with Be and has a strength of 1 and elasticity.

It is an element that contributes to improving heat resistance, stress relaxation resistance, etc.

Further, it has the effect of refining the casting structure and hot working structure and preventing coarsening of crystal grains during solution treatment.

In order to exhibit such an effect, the Ni content must be 0.
．． If it is less than 1 wt%, the desired effect cannot be obtained; on the other hand, if 3.
When the content exceeds 0 wt%, the electrical conductivity decreases.81
The content is set in the range of 0.1 wt% to 3.0 wt%, since it becomes a serious problem and is also economically disadvantageous.

(2) Be Be is less than Ni when its content is less than 0.005 wt%.
Even in the coexistence with Be, the desired effects on strength, elasticity, heat resistance, stress relaxation properties, etc. cannot be obtained. On the other hand, when the Be content exceeds 0.5 wt%, electrical conductivity decreases and press formability deteriorates. decreases significantly.

Moreover, if the content exceeds 0.5 wt%, the castability will decrease and the oxide film will become strong during heat treatment, causing manufacturing problems, so the content should be 0.005 to 0.5 wt%.
wt% range, more preferably 0.03-0.21wt
%.

(3) Sn Sn is dissolved in the Cu matrix to improve strength and elasticity without reducing additive properties, and also improves corrosion resistance and oxidation resistance against salt water, SOz gas, etc. It is an element.

In order to fully exhibit this effect, 0.1 wt%
It is necessary to contain the above, but if it exceeds 3.0 wt%, the electrical conductivity will decrease, the castability and hot workability will decrease significantly, and it will be economically disadvantageous, so the content is The range is 0.1 to 3.0 wt%.

(4) Component composition ratio of Ni:Be Furthermore, Ni and Be precipitate as a Ni-Be-based intermetallic compound, thereby achieving the above-mentioned basic features of the present invention.

In order to more fully exhibit the property enhancement by this Nf-Be based intermetallic compound, it is better to set the component composition ratio (weight ratio) of Ni/Be preferably in the range of 5 to 30.

When the component composition ratio of Ni/Be is outside the above range, the amount of Ni and Be dissolved in the matrix increases, and the electrical conductivity tends to decrease.

(5) Zn Zn is an element that effectively prevents welding during heat treatment in the copper-based alloy according to the present invention. In addition, it functions as a deoxidizing agent during melting and casting, and also effectively removes oxide films during pickling after hot rolling and heat treatment, and further improves the weather resistance of solder plating of the copper-based alloy according to the present invention. is also effective.

In order to exhibit such an effect, 0.01wt%
Although the above content is necessary, on the other hand, if the content exceeds 5.0 wt%, the electrical conductivity decreases significantly and the stress corrosion cracking resistance decreases.

Therefore, the Zn content is in the range of 0.01 to 5.0 wt%.

(6) Subcomponents Furthermore, as subcomponents, Ti, Cr, Zr, Mg
.

Ni, Be, Sn or Ni, one or more selected from the group consisting of Fe, Co, Sl, AJL, P, B, etc.
By including it in the copper-based alloy of the present invention consisting of Be, Sn, and Zn, various properties such as strength, elasticity, heat resistance, and stress relaxation properties of the steel-based alloy of the present invention are further improved. Also,
Casting, hot rolling.

It also contributes to the refinement of crystals during heat treatment.

In order to make full use of this effect.

One or more selected from the above subcomponents in total of 0.
005 wt% or more, while 1.
If the content exceeds 0 wt%, there will be a noticeable decrease in workability, which will cause manufacturing problems such as a decrease in flowability during casting and the formation of a strong oxide film during heat treatment, which will also be economically disadvantageous. Become.

Therefore, the above-mentioned subcomponents may be one type or two or more types in total.
, 005 to 1.0 wt%.

It goes without saying that the effects of adding the above-mentioned subcomponents are similar to those described above for the copper-based alloys of the WSL invention and the second invention.

(7) Oxygen content The oxygen content in the copper-based alloy according to the present invention is 50 pp.
It is preferable that the amount is less than 50 ppm. This is because when 50 ppm or more is present in the copper-based alloy, the affinity for oxygen becomes large and e oxidizes to become BeO.

This is because the above-mentioned properties including plating properties and plating reliability will be deteriorated.

Furthermore, if the oxygen content is more than 50 ppm, there is a concern that hydrogen embrittlement may occur on the surface and inside of the copper-based alloy when H2 gas is used in the manufacturing process of the copper-based alloy.

Next, the present invention will be specifically explained using examples.

(D) Examples Example 1 Copper-based alloy No., L whose chemical composition values (wt%) are shown in Table 1
～No. 20 was attacked using a high frequency induction melting furnace, and 2
It was cast into an ingot of 0 x 50 x 220 (am).

However, the atmosphere during melting and casting was set to an Ar gas seal, and water cooling was performed immediately after casting. After facing each ingot, cold rolling and annealing were repeated until the ingot had a thickness of Q and 8 arms.

Thereafter, after heat treatment at a temperature of 600 to 850°C for 5 minutes, quenching with water and pickling were performed.

This heat treatment temperature is the optimum condition for each alloy, so No.
, 3.6, 7.9, 12, 14.20 are 850℃, No.
, 1.2, 4.5, 8, 10.11° 13.15, 18
．． 19 is 800℃, No. 17 is 700℃, No. 16
The temperature was 600°C.

The heat-treated material obtained as described above was cold-rolled to a thickness of 0.31 mm, and heat-treated at a temperature of 300 to 500°C for 60 minutes.

However, in order to set this heat treatment temperature to the optimum condition for each alloy, No. 3.6, 7, 9, and 12.14 were heated to 500°C,
o, 1.2, 4.5.8, 10, 11 13.15, 1
8, 19.20 is 450℃, No. 17 is 400℃, N
o, 16 was set at a temperature of 300°C.

Each predetermined test piece was created using the obtained test material, and hardness, tensile strength, spring limit value, electrical conductivity, and bending workability were measured. The results are shown in Table 1.

The measurement methods for hardness, tensile strength, spring limit value, and electrical conductivity are JIS-Z-2244 and JIS
-Z-2241, JIS-H-3130 and JIS-
Performed according to H-0505.

Bending workability is determined by 90'W bending test (CES->1-00
02-6r R=O, lam, rolling direction and vertical direction), those with a good ridge surface in the center are marked with ○, those with wrinkles are marked with Δ, and those with cracks are marked with x. evaluated.

From the results shown in Table 1, No. 1 to 1 according to the present invention
The copper-based alloy No. 15 has an excellent balance of hardness, tensile strength, spring limit value, and electrical conductivity, and also has good bending workability. Therefore, it is a copper-based alloy that has very excellent properties and is suitable as a material for terminals in wire harnesses.

On the other hand, comparative alloy No. 16 has a lower amount of Be than the component composition range of the present invention, comparative alloy No. 16 has a lower amount of Nil,
Comparative alloy Nos. 17 and 18, which do not contain Sn, have lower hardness, tensile strength, and spring limit values than the alloys of the present invention.

Further, comparative alloy No. 19, which has a higher Ni content than the composition range of the present invention, has low conductivity and poor bending workability, and comparative alloy No. 20, which has a higher Be content, has poor bending workability.

Example 2 The hardness, tensile strength, spring limit value, and conductivity of the present invention alloy NO12 shown in Table 1 of Example 1 and the commercially available phosphor bronze 2N (C5191-H) were measured. ! The bending workability, stress relaxation properties and heat resistance were tested and measured. The results are shown in Table 2.

Hardness, tensile strength, spring limit value, electrical conductivity 9, and bending workability were measured using the same methods as in Example 1.

In addition, in the stress relaxation test, the stress at the center of the specimen was 40 K.
Make a U-shaped bend so that it becomes 150
The stress relaxation rate was calculated using the following equation, using the bending pattern after being held at a temperature of 200 hours at a temperature of .degree.

Stress relaxation rate (2) = [(L+ -Lt) / (L+ -Lo)IXlo
oLo: Length of the jig (1) Ll: Length of the sample at the start (■■) Lt: Horizontal distance between the edges of the sample after treatment (-1) Furthermore, in the heat resistance test, the hardness of the sample is equal to the initial hardness. The temperature was set at 80% (maintained for 30 minutes).

From the results shown in Table 2, the copper-based alloy C of the present invention has significantly higher conductivity, stress relaxation resistance, and heat resistance than phosphor bronze, which is a typical conventional wire harness terminal material. I can see that it is improving. Therefore, it is clear that the copper-based alloy of the present invention has a high degree of environmental resistance and is extremely reliable.

(e) Effects of the Invention As is clear from the above examples, the copper-based alloy according to the present invention has high strength, high elasticity, high electrical conductivity, and has good bending workability, stress relaxation resistance, and heat resistance. It has excellent properties and can be used for various purposes, but it is especially suitable as a terminal material for wire harnesses.

Furthermore, the alloy of the present invention is an epoch-making copper-based alloy suitable for terminals, which can fully respond to the recent trends in the miniaturization and weight reduction of automotive electrical components and the increase in wiring density.

Claims (3)

[Claims] (1) Ni: 0.1 to 3.0 wt%, Be: 0.005-0.5wt%, Sn: 0.1-3.0wt%, The remainder: Cu and inevitable impurities, A high-strength, high-conductivity copper-based alloy characterized by comprising: (2) Ni: 0.1 to 3.0 wt%, Be: 0.005-0.5wt%, Sn: 0.1-3.0wt%, Zn: 0.01-5.0wt%, The remainder: Cu and inevitable impurities, A high-strength, high-conductivity copper-based alloy characterized by comprising: (3) Ni: 0.1 to 3.0 wt%, Be: 0.005 to 0.5 wt%, Sn: 0.1 to 3.0 wt%, Zn: 0.01 to 5.0 wt%, Furthermore, Ti, Cr, Zr, Mg, Fe, Co, S
A total of 0 of one or more of i, Al, P, or B
．． A high-strength, high-conductivity copper-based alloy characterized by containing 0.005 to 1.0 wt%, with the remainder consisting of Cu and unavoidable impurities.