JP4708833B2 - High strength copper alloy material for precision conductive spring with excellent sag resistance and its manufacturing method - Google Patents

Description

  The present invention relates to a high-strength and high-conductivity copper alloy material excellent in sag resistance, and a method for producing the same, particularly in the use of conductive spring products such as suspension wires for optical pickups.

  Copper is widely used as an electrical / electronic material because of its low electrical resistance and excellent electrical conductivity, and its application is widely used from various electric wires to various parts such as connectors, terminals, and switches. However, on the other hand, since copper is soft, it is inherently unsuitable for applications that require high strength such as spring products.

  Therefore, conductive spring products that require both high conductivity and high strength, such as suspension wires for optical pickups, have conventionally used high-strength stainless steel as the core and copper plated or clad on the surface. Copper alloys such as phosphor bronze and beryllium copper obtained by adding other elements to copper are used.

  However, although the former copper coating material can maintain high strength depending on the strength of the core material itself, it is likely to cause variations in quality characteristics due to peeling from the copper-coated core material and non-uniformity of the copper coating state. There is a problem in that the process is complicated, and deterioration in quality and increase in manufacturing cost are inevitable.

  On the other hand, the latter copper alloy is widely used because it has high strength and relatively good electrical conductivity, and there are few problems such as variations in quality as in a copper coating material. As its properties, for example, beryllium copper has a high tensile strength of about 1400 MPa (pure copper is about 200 MPa) and conductivity is relatively good at about 20% IACS, but Be is harmful to the human body and includes this. In the case of discarding parts and devices, environmental measures such as providing a separate processing step are necessary, and their use has recently been limited. On the other hand, although the phosphor bronze does not have such a problem, it does not reach the strength of beryllium copper, so that it is not satisfactory as a stable spring material that requires sag resistance.

Under such circumstances, there has been a demand for a copper alloy material having high strength, high conductivity, and no harmful elements in place of beryllium copper. As a copper alloy material having such characteristics, for example, Ni In a copper alloy containing 2.0 to 4.8% by weight, 0.2 to 1.4% by weight of Si, and 0.05 to 1.5% by weight of Mg, precipitates or inclusions present therein (Patent Document 1), or Cu containing 4 to 32 atomic% of Ag is cast, quenched, and then cold worked (Patent Document 2). ing.
Japanese Patent Application Laid-Open No. 11-222641 JP 2000-199042 A

  However, the former has a strength (tensile strength) of about 700 to 1000 MPa, which is not satisfactory as a material for the conductive spring. The latter patent document 2 also has a higher strength (tensile strength) than the former patent document 1, and shows applications such as various cables, windings, and other shaft reinforcing materials. However, in particular for spring products, it is not sufficient that the strength is simply high. For example, it is necessary to provide various characteristics such as elastic characteristics, fatigue characteristics, and sag resistance. Although important in terms of life in spring products, the document does not suggest anything about this point.

Thus, in recent years, as a copper alloy material for a highly safe conductive spring that replaces beryllium copper, a material that is particularly excellent in sag resistance as well as strength and conductivity has been demanded. No one can meet the demand. Therefore, as a result of earnest research to deal with such problems of the prior art, the present invention adds Cu and Ag in the structure by adding a predetermined amount of Ni and Si to the copper-silver alloy according to Patent Document 2 in combination. The present invention has been completed with the conclusion that it is effective to combine the eutectic phase particles of Ni and the Ni ₂ Si phase particles of Ni and Si.

  That is, the present invention provides a copper alloy material that does not contain a harmful element such as Be and has sufficient strength, sag resistance, and conductivity required for the use of the conductive spring material, and a method for producing the same. It is for the purpose of provision.

In order to achieve the object, the invention according to claim 1 of the present application is, by mass, 5.0 to 16.0% Ag, 1.0 to 5.0% Ni, and 0.2 to 1.2. % Si, the balance is Cu and inevitable impurities, and the contents of Ag, Ni and Si are a (mass%), b (mass%) and c (mass%), respectively. .0 ≦ have a relationship of {(1/4) × a + b } /c≦14.0, the eutectic phase and _Ni 2 Si particles between Cu and Ag contained in the composite in a tissue, by the following equation It is a high-strength copper alloy material for precision conductive springs with excellent sag resistance, characterized in that the sag rate (γ) is 1.2% or less.
γ (%) = [(L ₀ −L ₁ ) / L ₀ ] × 100
(Here, L ₁ and L ₀ are the free length when the load or the molded product made from the material is loaded for 3 minutes with the stress corresponding to 40% of its 0.2% proof stress, and the initial length when unloaded. Free length)

  The invention according to claim 2 is the copper alloy material according to claim 1, wherein the alloy composition further includes 0.2 to 1.0 mass% of Sn and / or 0.3 to 1.2 mass% of Zn. It is characterized by containing.

The invention according to claim 3 is the copper alloy material according to claim 1 or 2, wherein the 0.2% proof stress is 900 MPa or more and the conductivity is 25% IACS or more. .

The invention described in Claim 4 is the mass, containing 5.0 to 16.0% of Ag, 1.0 to 5.0 percent of Ni and 0.2 to 1.2% of Si, balance Ri Do Cu and inevitable impurities, wherein Ag, Ni and Si content, respectively a (mass%), when and b (wt%) and c (mass%), 8.0 ≦ {(1 a near Ru copper alloy material relation /4)×Atasub}/c≦14.0, cold working after subjected to primary heat treatment 1-100 hours at a temperature 300 to 600 ° C., working ratio of 50% or more gastric row, the later cold working, the first heat treatment temperature below the temperature at predetermined time heat treatment to second heat treatment sexual excellent electric and electronic parts precision conductive spring for high sag resistance, characterized in that applying It is a manufacturing method of a strength copper alloy material.

By subjecting the copper alloy material having the above composition to a primary heat treatment, a Cu / Ag eutectic phase (CuAg phase) and Ni ₂ Si phase particles are formed in a composite form in the material structure. And by carrying out cold working at a working rate of 50% or more, the structure is fibrillated, and high strength and sag resistance are obtained.

The secondary heat treatment is desirably performed after the copper alloy material is formed into a product shape as a spring. By performing the secondary heat treatment, Ni ₂ Si phase particles are further precipitated and the sag resistance is improved.

Here, primary heat treatment mainly focuses on precipitation of CuAg phase, and precipitation of Ni ₂ Si phase particles is secondary, whereas secondary heat treatment mainly focuses on precipitation of Ni ₂ Si phase particles. . The CuAg phase is excellent in cold workability, and is fiberized by applying cold work after precipitation to obtain high strength. On the other hand, Ni ₂ Si phase particles are an intermetallic compound and have poor plastic workability. If they are excessively precipitated, the workability is adversely affected. On the other hand, a large amount of Ni ₂ Si phase particles precipitate, so that plastic deformation hardly occurs. Improves sag resistance. Therefore, in the first heat treatment by heat at relatively high temperatures, thereby often precipitate CuAg phase. After that, after cold working and forming into a product shape as a spring, secondary heat treatment is performed at a relatively low temperature, Ni ₂ Si phase particles are precipitated, and both workability and sag resistance are achieved. I am trying. If the temperature of the secondary heat treatment is too high, recrystallization occurs and the effect of fiber reinforcement by the CuAg phase is lost.

According to the present invention, there is no environmental problem, and the fine particles obtained by complex formation of CuAg phase particles and Ni ₂ Si phase particles have high strength and high conductivity, and are also resistant to sag. A copper alloy material having improved resistance can be obtained, and by using this, a conductive spring material having excellent sag resistance and a long life can be obtained.

  Hereinafter, although embodiment of this invention is described, the unit "%" of content of each structural element shows "mass%".

The copper alloy material of the present invention contains 5.0 to 16.0% Ag in Cu, thereby crystallizing a eutectic phase of Cu and Ag, and maintaining strength while maintaining good conductivity. By increasing and further containing 1.0 to 5.0% Ni and 0.2 to 1.2% Si, further compound particles of Ni and Si (Ni ₂ Si phase) in the Cu base material In addition, the composite formation of these eutectic phases and Ni ₂ Si particles is intended to further increase the strength while suppressing the decrease in conductivity, and to improve the sag resistance when used for the spring. It is intended to improve.

  Here, “sagging” means, for example, “Spring Technology Workshop Bulletin” p. 2828 (issued in October 2001), “Phenomenon in which plastic strain occurs under low stress within the elastic limit”. Generally, “strain is repeatedly applied in the elastic region. If the strain is applied for a long period of time, it means the same phenomenon as when a strain larger than the strain actually applied is applied and a strain that does not return even when unloaded is generated.

The measurement is performed, for example, on a test wire having a predetermined shape by applying a stress in the elastic region of the wire and leaving it for a predetermined time, and then releasing the strain before or after stress loading. In the present invention, when a load corresponding to 40% of the 0.2% proof stress value of the target wire or its molded product is loaded for 3 minutes and then unloaded. The residual strain amount of [(L ₀ −L ₁ ) / L ₀ ] × 100 can be obtained from the calculation formula. In this case, when the wire is used in a state where a bending stress such as a torsion spring is applied, the chord length ratio of the wire after unloading by applying the 40% equivalent stress is obtained from the above formula.

Moreover, also in the case of molded articles, such as a compression coil spring, a sag rate can be calculated | required in the following ways, for example. That is, when a stress-strain diagram pre-stressed with respect to the spring is obtained, and left unloaded for a predetermined time in a state where 40% of the stress corresponding to 0.2% proof stress is added in the diagram. The change between the free length (L ₁ ) and the initial free length (L ₀ ) is calculated in the above equation. As is clear from these relationships, the smaller the value, the better the sag resistance. For those used for the optical pickup spring and other precision device springs, the more preferred sag resistance is 1.2% or less.

Therefore, in the present invention, in order to improve such a phenomenon, it is effective to make a form that can withstand the deformation behavior within the elastic limit as well as increasing the strength of the wire, so that the CuAg eutectic phase and Ni ₂ are effective. It was decided to form a composite of Si compounds . Among these, by combining these eutectic phases and compounds in a distributed state in which the eutectic phase and the compound are continuously arranged along the longitudinal direction or in a state of being stretched into a fiber shape, a large resistance to a bending stress or the like is obtained. It will have.

From the viewpoint of generating such precipitates, in the present invention, the content of each element is set to the above-described range. That is, if the Ag content is less than 5.0%, the strength is insufficient, and if it exceeds 16.0%, the strength becomes too high and cold working (drawing) becomes difficult. The preferable Ag content is in the range of 8.0 to 14.0%, more preferably in the range of 9.5 to 12.0%. On the other hand, if the Ni content is less than 1.0%, the formation of the Ni ₂ Si is reduced and the strength cannot be sufficiently improved. On the other hand, if it exceeds 5.0%, the strength increases, but cold working becomes difficult. A preferable Ni content is in the range of 1.5 to 3.2%.

Furthermore, since Si is an intermetallic compound with Ni and produces Ni ₂ Si, the optimum Si content is determined when the Ni content is determined. That is, when the Si content is less than 0.2%, the amount of Ni ₂ Si deposited decreases, and the strength cannot be sufficiently improved. On the other hand, if it exceeds 1.2%, the strength does not change and the conductivity is lowered. A preferable Si content is in the range of 0.3 to 0.8%.

In the present invention, when the contents of Ag, Ni, and Si are a (%), b (%), and c (%), respectively, 8.0 ≦ {(1/4) × a + b} / c It is preferable to satisfy ≦ 14.0 . It is possible to increase the strength by promoting work hardening and precipitation hardening when performing cold working and precipitation treatment by balancing the contents of Ag, Ni and Si, and Based on the knowledge that good conductivity can be maintained.

That is, FIG. 1 shows various changes in the contents of Ag, Ni and Si within the above-mentioned range, and [{(1/4) × a + b} / c] value (A value) and strength (proof strength, tensile strength). The relationship between the strength and the conductivity is shown. [{(1/4) × a + b} / c] value and the strength are in a positive proportional relationship, and [{(1/4) ) × a + b} / c] value and conductivity are in a negative proportional relationship, and specifying the [{(1/4) × a + b} / c] value indicates that stable characteristics can be obtained. .
If the [(1 / 4a + b) / c] value is less than 8.0, the strength cannot be increased sufficiently. On the other hand, if the [(1 / 4a + b) / c] value exceeds 14.0, the strength is sufficient. sag resistance is not be obtained.

  In order to further improve the sag resistance, the copper alloy of the present invention can contain Sn and / or Zn as necessary. The content of Sn is preferably in the range of 0.2 to 1.0% and Zn in the range of 0.3 to 1.2%. If Sn is less than 0.2%, the effect of addition cannot be obtained, and if it exceeds 1.0%, the workability decreases. Moreover, if Zn is less than 0.3%, the effect by addition cannot be obtained, and if it exceeds 1.2%, the workability deteriorates as in the case of Sn.

  The copper alloy of the present invention may contain, for example, 3% or less of inevitable impurities in total. Inevitable impurities include Mg, Mn, Cr, Co, Ti, Al, Sb, As, Pb, Bi, O, P, S, Se, Te, and the like.

  The copper alloy of the present invention preferably has a 0.2% yield strength of 900 MPa or more and an electrical conductivity of 25% IACS or more. If the 0.2% yield strength is less than 900 MPa, the strength as a spring material is sufficient. In addition, when the conductivity is less than 25% IACS, the loss when the conductive material is used increases. More preferably, the 0.2% proof stress is about 1000 to 1500 MPa, and the conductivity is 30% IACS or more.

  Here, 0.2% proof stress refers to the stress when a permanent strain of 0.2% is produced when a tensile test is performed in accordance with JIS Z 2241 “Metal Material Tensile Test Method”. The rate can be measured by a four-terminal method (sample length: 100 mm) in a constant temperature bath at 20 ° C. in accordance with JIS C 3002. In particular, in the case of a hard wire, the elastic characteristics are improved, and it is possible to withstand a greater stress, and the application can be expanded.

  The copper alloy material of the present invention combines the above precipitates in the structure with such characteristics, and since the precipitates are hard and fine, they have dispersion strengthening or fiber reinforced characteristics. Can improve the sag resistance. In particular, it becomes more prominent when these precipitates are arranged with directionality along the longitudinal direction. Although the conductivity may be slightly lowered by such a precipitate, the present invention has no substantial influence since it has a conductivity of 25% IACS or more.

  The copper alloy material as described above is preferably manufactured by the following method.

That is, by mass, 5.0 to 16.0% Ag, 1.0 to 5.0% Ni and 0.2 to 1.2% Si, and 0.2 to 1.0 if necessary. A copper alloy material containing 1% Sn and / or 0.3 to 1.2% Zn, the balance being Cu and inevitable impurities, is subjected to a primary heat treatment at a temperature of 300 to 600 ° C. for 1 to 100 hours. Thus, the eutectic phase (CuAg phase) of Cu and Ag and Ni ₂ Si phase particles are formed in the structure in a composite, and then cold working is performed at a working rate of 50% or more. For cold working, wire drawing, rolling, or other processing methods are employed depending on the final shape.

The first feature is that a eutectic phase (CuAg phase) composed of Ag and Cu is positively precipitated in the Cu matrix by the primary heat treatment. Although this CuAg phase is harder than the parent phase Cu, it has relatively ductility, and has a fiber structure that extends finely, for example, along its longitudinal direction by subsequent cold working. In this case, Ni ₂ Si particles can be precipitated together with the eutectic phase. When the heat treatment temperature is less than 300 ° C. or the heat treatment time is less than 1 hour, the precipitation is not sufficiently performed. Conversely, when the heat treatment temperature exceeds 600 ° C. or the heat treatment time exceeds 100 hours, Solid solution of CuAg phase and coarsening of Ni ₂ Si particles occur. This precipitation heat treatment is more preferably performed at a temperature of 350 to 450 ° C. for 5 to 20 hours.

In the cold working after such a primary heat treatment step, the CuAg phase is stretched into a fiber shape and improves the strength of the copper alloy material together with the precipitation of Ni ₂ Si particles.

  In the present invention, at least one intermediate heat treatment step may be performed during such cold working. As heat treatment conditions at that time, for example, in a vacuum or in an argon or nitrogen atmosphere, a temperature of 300 to 600 ° C. is preferably about 1 minute to less than 1 hour, and a temperature of 400 to 580 ° C. is more preferably 3 to 30 minutes. . By performing such an intermediate heat treatment, it is possible to perform processing with a high degree of processing. If the temperature is less than 300 ° C. or the time is less than 1 minute, the workability cannot be improved sufficiently. Conversely, if the temperature exceeds 600 ° C. or the time exceeds 10 hours, recrystallization occurs. Therefore, a predetermined strength cannot be obtained.

The copper alloy material thus obtained is then cut or processed into a predetermined product shape to obtain a conductive spring molded product. The product shape of the conductive spring molded product is not particularly limited, and may be a coil shape (coil spring), a linear shape (linear spring), or a plate shape (leaf spring). May be. In the present invention, after cutting or processing into a predetermined product shape, it is preferable to perform a secondary heat treatment at a temperature lower than the primary heat treatment, preferably 150 to 400 ° C., more preferably 200 to 350 ° C. By performing such secondary heat treatment, it is possible to further improve the sag resistance when used as a conductive spring material. This is presumably due to the precipitation of Ni ₂ Si particles. Under a temperature condition in which the secondary heat treatment temperature exceeds the primary heat treatment temperature, recrystallization occurs and the strength decreases. The time for the secondary heat treatment is a time required for improving the sag resistance according to the heat treatment temperature, and is, for example, 1 minute to 5 hours, preferably 3 minutes to 1 hour, more preferably in the air. 5 to 30 minutes.

  The copper alloy material according to the present invention has high strength, high electrical conductivity, and excellent sag resistance. Various electrical properties such as suspension wires for optical pickups and conductive spring materials for LSI inspection are required. -Useful as a precision conductive spring material for electronic parts.

  Next, examples of the present invention will be described, but the present invention is not limited to the following examples.

Examples and Comparative Examples Using a horizontal continuous casting machine having a graphite mold provided with a water cooling jacket on the outer periphery, casting rods having various compositions as shown in Table 1 and having a wire diameter of 9.5 mm were cast. Next, these cast rods were heat-treated and cold worked under various conditions shown in Table 1 to obtain copper alloy wires having a wire diameter of 0.7 mm.

That is, in Comparative Example 11-1 and Example 11-2 , the cast rod was subjected to primary heat treatment at 450 ° C. for 10 hours in a nitrogen atmosphere, and then cold worked. During the cold working, when the wire diameter was drawn to 3.0 mm, an intermediate heat treatment was performed at 450 ° C. for 6 minutes in an argon atmosphere.

In Comparative Example 11-3, Example 11-4, Comparative Example 12-1, Example 12-2, Comparative Example 13-1, and Example 13-2 , the cast rod was subjected to primary heat treatment at 450 ° C. for 10 hours. After applying, it was cold worked. During the cold working, when the wire diameter was drawn to 3.0 mm, an intermediate heat treatment was performed at 550 ° C. for 6 minutes.

In Comparative Example 14-1 and Comparative Example 14-2 , the cast rod was cold worked without being subjected to heat treatment. During the cold working, when the wire diameter was drawn to 3.0 mm, an intermediate heat treatment was performed at 500 ° C. for 6 minutes.

In Comparative Example 14-3 and Example 14-4 , the cast rod was subjected to primary heat treatment at 350 ° C. for 10 hours and then cold worked. During the cold working, when the wire diameter was drawn to 3.0 mm, an intermediate heat treatment was performed at 550 ° C. for 6 minutes.

In Comparative Example 14-5 and Example 14-6 , the cast rod was subjected to a primary heat treatment at 400 ° C. for 10 hours and then cold worked. During the cold working, when the wire diameter was drawn to 3.0 mm, an intermediate heat treatment was performed at 550 ° C. for 6 minutes.

A small amount of Ni ₂ Si particles was confirmed together with the CuAg eutectic phase for those subjected to the primary heat treatment of each of the examples and comparative examples .

Thereafter, the obtained copper alloy wire material having a wire diameter of 0.7 mm was processed into a coil shape, and a compression coil spring (coil outer diameter: 7.70 mm, coil average diameter: 7.00 mm, free length (L ₀ ): 13 0.5 mm, total number of turns: 6.5, effective number of turns: 4.5). In Example 11-2, Example 11-4, Example 12-2, Example 13-2, Comparative Example 14-2, Example 14-4, and Example 14-6, after processing into a coil shape, 250 ° C. A secondary heat treatment was performed for 1 hour.

Comparative Examples 21-1 and 21-2
A copper alloy composed of 10.0% by mass of Ag and the balance of Cu is cast using a horizontal continuous casting machine similar to that of the example to cast a casting rod having a wire diameter of 9.5 mm. Processing was performed to obtain a copper alloy wire having a wire diameter of 0.7 mm. Thereafter, the obtained copper alloy wire having a wire diameter of 0.7 mm was processed into a coil shape to produce a compression coil spring having the same shape and the same dimensions as those of the example. In Comparative Example 21-2 , heat treatment was performed at 260 ° C. for 30 minutes after processing into a coil shape.

Comparative Examples 22-1 and 22-2
A copper alloy wire rod having a wire diameter of 0.7 mm made of 2 mass% Be and the balance Cu was processed into a coil shape to produce a compression coil spring having the same shape and the same dimensions as those of the example. In Comparative Example 22-1 , heat treatment was performed at 260 ° C. for 30 minutes after processing into a coil shape. Further, in Comparative Example 22-2 , heat treatment was performed at 300 ° C. for 1 hour after processing into a coil shape.

Comparative Examples 23-1 and 23-2
A copper alloy composed of 3.0% by mass of Ag and the balance of Cu is cast using a horizontal continuous casting machine similar to that of the example to cast a casting rod having a wire diameter of 9.5 mm. Processing was performed to obtain a copper alloy wire having a wire diameter of 0.7 mm. Thereafter, the obtained copper alloy wire having a wire diameter of 0.7 mm was processed into a coil shape to produce a compression coil spring having the same shape and the same dimensions as those of the example. In Comparative Example 23-2 , heat treatment was performed at 260 ° C. for 30 minutes after processing into a coil shape.

For the compression coil springs obtained in each of the above Examples and Comparative Examples, the sag rate (γ) was measured, and 0.2% proof stress , tensile strength, and electrical conductivity were measured for the wire that had been processed under the same conditions. It was measured. These results are shown in Table 2 together with the tensile strength and conductivity measured for the samples taken before cold working. The sag rate (γ) was calculated from the following equation by measuring the free length (L ₁₀ ) after a compression coil spring was loaded 10 times with a load having a spring length of 12 mm and 8 mm.
γ (%) = [(L ₀ −L ₁₀ ) / L ₀ ] × 100
Further, 0.2% proof stress and tensile strength were measured according to JIS Z 2241, and conductivity was measured according to JIS C 3002.

* 太字で示した例（11-2,11-4,12-2,13-2,14-4,14-6）は実施例、その他は比較例

* Examples shown in bold (11-2,11-4,12-2,13-2,14-4,14-6) are examples, others are comparative examples

As shown in Table 1 and Table 2, the conductive springs obtained in the examples have high strength, high conductivity, and excellent sag resistance. Although the Cu-Ag alloys of Comparative Examples 21-1 and 21-2 have good electrical conductivity of 70% IACS or higher, the sag ratio is large at about 3.9% and about 1.8%, and as a spring material, Not always enough. On the other hand, all of the embodiments of the present invention have a low settling rate . In particular, in the examples subjected to the secondary heat treatment, the sag rate is 1% or less, and has the same sag resistance as the beryllium copper alloys of Comparative Examples 22-1 and 22-2 , and In terms of conductivity, they are superior to them.

  From these measurement results, it was confirmed that the copper alloy material of the present invention has sufficient characteristics for spring forming. Therefore, it has sufficient performance as a substitute material for beryllium copper alloys containing harmful substances as a conductive spring material, particularly in the precision field.

It is a graph which shows the relationship between [ {(1/4) * a + b} / c ] value, intensity | strength, and electrical conductivity.

Claims (6)

Containing 5.0 to 16.0% Ag, 1.0 to 5.0% Ni and 0.2 to 1.2% Si by mass, with the balance consisting of Cu and inevitable impurities, When the contents of Ag, Ni and Si are a (mass%), b (mass%) and c (mass%), respectively, 8.0 ≦ {(1/4) × a + b} /c≦14.0 It is characterized by the fact that the structure contains a eutectic phase of Cu and Ag and Ni ₂ Si particles in a composite, and the sag rate (γ) determined by the following formula is 1.2% or less. High strength copper alloy material for precision conductive springs with excellent sag resistance.
γ (%) = [(L ₀ −L ₁ ) / L ₀ ] × 100
(Here, L ₁ and L ₀ are the free length when the load or the molded product made from the material is loaded for 3 minutes with the stress corresponding to 40% of its 0.2% proof stress, and the initial length when unloaded. Free length)   2. The electrical / electronic component precision conductive according to claim 1, wherein the alloy composition further contains 0.2 to 1.0 mass% of Sn and / or 0.3 to 1.2 mass% of Zn. High strength copper alloy material for spring.   The high-strength copper alloy material for precision conductive springs according to claim 1 or 2, wherein the 0.2% proof stress is 900 MPa or more and the electrical conductivity is 25% IACS or more.   Containing 5.0 to 16.0% Ag, 1.0 to 5.0% Ni and 0.2 to 1.2% Si by mass, with the balance consisting of Cu and inevitable impurities, When the contents of Ag, Ni and Si are a (mass%), b (mass%) and c (mass%), respectively, 8.0 ≦ {(1/4) × a + b} /c≦14.0 The copper alloy material having the following relationship is subjected to a primary heat treatment at a temperature of 300 to 600 ° C. for 1 to 100 hours, followed by cold working at a processing rate of 50% or more, and after the cold working, the primary heat treatment A method for producing a high-strength copper alloy material for precision conductive springs having excellent sag resistance, characterized by performing a secondary heat treatment for a predetermined time at a temperature below the temperature.   5. An electric / electronic component precision conductive spring with excellent sag resistance according to claim 4, wherein an intermediate heat treatment is performed at a temperature of 300 to 600 [deg.] C. for 1 minute to less than 1 hour during the cold working. For producing high-strength copper alloy materials for use.   6. The sag resistance according to claim 4, wherein the copper alloy material further contains 0.2 to 1.0 mass% of Sn and / or 0.3 to 1.2 mass% of Zn. A high-strength copper alloy material for precision conductive springs with excellent electrical and electronic parts.

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