CN102453815B - Copper alloy, forged copper adopting the copper alloy, electronic component, connector and method for manufacturing copper alloy - Google Patents

Abstract

The present invention provides titanium copper, wrought copper, electronic components, connectors and a manufacturing method thereof having excellent strength and bending workability. Copper alloy containing 2.0 to 4.0% by mass of Ti and 0 to 0.2% by mass in total as a third element selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B and one or more of P, and the remainder contains copper and unavoidable impurities, wherein, when measuring the X-ray diffraction intensity of the rolling surface, the X-ray diffraction intensity I of the rolling surface is the same as that of the (311) plane and ( The ratio of the X-ray diffraction intensity I ₀ (I/I ₀ ) of the pure copper powder in the 200) plane satisfies the following relational formula: {I/I ₀ (311)}/{I/I ₀ (200)}≤2.54 , and the ratio (I/I ₀ ) of the X-ray diffraction intensity I of the rolling surface to the X-ray diffraction intensity I ₀ of the pure copper powder in the (220) plane and (200) plane satisfies the following relational formula: 15≤{ I/I ₀ (220)}/{I/I ₀ (200)}≤95.

Description

Copper alloy, wrought copper using same, electronic component and connector, and manufacturing method of copper alloy

technical field

The present invention relates to a titanium-containing copper alloy suitable as a material for electronic components such as connectors, a wrought copper (extruded copper product) using the same, an electronic component, a connector, and a method for producing the copper alloy.

Background technique

In recent years, along with the increasing miniaturization of electronic devices represented by portable terminals and the like, the pitch of connectors used therein tends to be narrowed and downsized. The smaller the connector, the narrower the width of the pins, forming a processed shape with less bending. Therefore, the raw materials used are required to have high strength required to obtain the necessary elasticity and excellent resistance to severe bending processing. Bending workability. Therefore, copper alloys containing titanium (hereinafter referred to as "titanium copper") have been used as materials for signal system terminals requiring material strength due to their relatively high strength and the best stress relaxation characteristics among copper alloys.

Titanium copper is an age-hardening copper alloy. Specifically, through solution treatment, a supersaturated solid solution of solute atoms Ti is formed, and if heat treatment is performed for a relatively long time at a low temperature from this state, the modulation structure in which the Ti concentration in the parent phase changes periodically due to spinodal decomposition Generated, strength increased. Based on the above-mentioned strengthening mechanism, various methods have been studied in order to further improve the characteristics of titanium copper.

In this case, the problem is that strength and bendability are opposite characteristics. That is, if the strength is increased, the bending workability will be impaired, and conversely, if the bending workability is emphasized, the desired strength will not be obtained.

Therefore, in the past, the concentration of the impurity element group solid-dissolved in the parent phase was specified by adding third elements such as Fe, Co, Ni, and Si (Patent Document 1), and they were used as the second phase particles (Cu-Ti-X system Particles) are precipitated in a prescribed distribution form to improve the regularity of the modulated structure (Patent Document 2), and the density of trace elements and second phase particles effective for making crystal grains finer is specified (Patent Document 3), making the crystal grains finer Research and development have been carried out in order to achieve both the strength and bendability of titanium copper from such angles as (Patent Document 4).

In addition, Patent Document 5 also proposes to focus on the crystal orientation, in order to prevent cracks during bending, adjust the hot rolling conditions to satisfy I{420}/I ₀ {420}>1.0, and then adjust the cold rolling rate to satisfy I{220 }/I ₀ {220}≤3.0 to control crystal orientation, thereby improving strength, bending workability and stress relaxation resistance.

[Prior art literature]

[Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2004-231985

[Patent Document 2] Japanese Unexamined Patent Publication No. 2004-176163

[Patent Document 3] Japanese Patent Laid-Open No. 2005-97638

[Patent Document 4] Japanese Patent Laid-Open No. 2006-283142

[Patent Document 5] Japanese Patent Laid-Open No. 2008-308734

Contents of the invention

The above-mentioned titanium copper is basically produced in the order of melting and casting of an ingot→homogenizing annealing→hot rolling→(repeated annealing and cold rolling)→final solution treatment→cold rolling→aging treatment, and the characteristics are obtained based on these steps improvement. However, there is room for further improvement in obtaining titanium copper having more excellent characteristics.

Therefore, the present invention attempts to improve the characteristics of titanium copper from a different angle than before, thereby providing a copper alloy having excellent strength and bending workability, forged copper using the same, electronic components and connectors, and a method of manufacturing copper alloys .

The inventors of the present invention found in the course of research to solve the above-mentioned problems that after solution treatment, if an appropriate heat treatment (sub-aging treatment) is performed to the extent that no or a part of the metastable phase or stable phase of titanium is formed, a certain amount of titanium will occur in advance. Spinodal decomposition to a certain extent, the strength of the final titanium copper obtained by subsequent cold rolling and aging treatment is significantly improved. That is, compared with the heat treatment step in which spinodal decomposition occurs in one stage of aging treatment in conventional titanium copper, the production method of titanium copper according to the present invention is significantly different in that spinodal decomposition occurs in two stages via cold rolling.

Furthermore, it can be seen that by further adjusting the addition amount of the third element to the most appropriate range, the conventional two-stage solution treatment for the purpose of solid solution and the second solution treatment for the purpose of recrystallization can be carried out. The treated titanium copper undergoes solid solution and recrystallization at the same time through a solution treatment to obtain titanium copper with excellent production efficiency and excellent balance between strength and bending workability.

One aspect of the present invention completed based on the above findings is a copper alloy containing 2.0 to 4.0% by mass of Ti and a total of 0 to 0.2% by mass of a third element selected from the group consisting of Mn, Fe, Mg, Co, Ni, and Cr. , V, Nb, Mo, Zr, Si, B and P, one or two or more, and the remainder contains copper and unavoidable impurities. Among them, when measuring the X-ray diffraction intensity of the rolled surface, the rolled surface The ratio (I/I 0 ) of X-ray diffraction intensity _I and the X-ray diffraction intensity I ₀ of the pure copper powder in the (311) plane and (200) plane satisfies the following relational formula (1): {I/I ₀ ( 311)}/{I/I ₀ (200)}≤2.54...(1), and the X-ray diffraction intensity I of the rolling surface and the X-ray diffraction intensity of the pure copper powder in the (220) plane and (200) plane The ratio of I ₀ (I/I ₀ ) satisfies the following relational expression (2): 15≦{I/I ₀ (220)}/{I/I ₀ (200)}≦95...(2).

Another aspect of the present invention is a copper alloy containing 2.0 to 4.0% by mass of Ti and a total of 0.01 to 0.15% by mass of a third element selected from the group consisting of Mn, Fe, Mg, Co, Ni, Cr, V, Nb , Mo, Zr, Si, B, and P, and the remainder contains copper and unavoidable impurities. Among them, when measuring the X-ray diffraction intensity of the rolled surface, the X-ray diffraction intensity of the rolled surface The ratio ₍ I/I 0 ) of the X-ray diffraction intensity I ₀ of the pure copper powder in the (311) plane and the (200) plane satisfies the following relational formula (1): {I/I ₀ (311)}/ {I/I ₀ (200)}≤2.54...(1), and the ratio of the X-ray diffraction intensity I of the rolling surface to the X-ray diffraction intensity I ₀ of the pure copper powder in the (220) plane and (200) plane (I/I ₀ ) satisfies the following relational expression (3): 30≦{I/I ₀ (220)}/{I/I ₀ (200)}≦95...(3).

Another aspect of the present invention is wrought copper, which includes the above-mentioned copper alloy.

Still another aspect of this invention is an electronic component containing the said copper alloy.

Still another aspect of this invention is a connector which has the said copper alloy.

Still another aspect of the present invention is the method for producing the above-mentioned copper alloy, which comprises: containing 2.0 to 4.0% by mass of Ti and 0 to 0.2% by mass in total as the third element selected from the group consisting of Mn, Fe, Mg, Co, One or two or more of Ni, Cr, V, Nb, Mo, Zr, Si, B, and P, and the rest of the copper alloy raw material contains copper and unavoidable impurities, heated at 730-880°C to The solid solution limit of Ti is the same as the addition amount, and the solid solution limit temperature is 0-20°C higher and the solution treatment is quenched. After the solution treatment, heat treatment is performed, and after the heat treatment, the final processing rate is 5-40%. Cold rolling, aging treatment after final cold rolling.

In the method for producing a copper alloy of the present invention, in one embodiment, the above-mentioned heat treatment increases the electrical conductivity, and when the titanium concentration (mass %) is [Ti], the increase value C (%IACS) of the electrical conductivity satisfies the following Relational formula (4): 0.5≤C≤(-0.50[Ti] ² -0.50[Ti]+14)...(4).

Detailed ways

<Ti content>

When Ti is less than 2% by mass, sufficient strength cannot be obtained because the strengthening mechanism achieved by the formation of the original modulation structure of titanium copper cannot be obtained. Conversely, if it exceeds 4.0% by mass, coarse TiCu ₃ is easily precipitated, and there is no strength. and tends to deteriorate bending workability. Therefore, the Ti content in the copper alloy of the present invention is 2.0 to 4.0% by mass, preferably 2.7 to 3.5% by mass, more preferably 2.9 to 3.3% by mass. By making the content of Ti appropriate, it is possible to achieve both strength and bending workability suitable for electronic components.

<third element>

Since the third element contributes to the miniaturization of crystal grains, a predetermined third element can be added. Specifically, performing solution treatment at a high temperature at which Ti is sufficiently solid-dissolved also tends to refine crystal grains and improve strength. In addition, the third element promotes the formation of the modulation structure. Furthermore, it also has the effect of suppressing the precipitation of _TiCu3 . Therefore, the original age hardening ability of titanium copper is obtained.

Among titanium copper, Fe has the highest effect. Also, Mn, Mg, Co, Ni, Si, Cr, V, Nb, Mo, Zr, B, and P can be expected to have an effect equivalent to Fe, and adding them alone is effective, but they can also be added in combination of two or more.

If the total content of these elements is 0.01% by mass or more, the effect will be exhibited, but if the total amount exceeds 0.5% by mass, the solid solution limit of Ti will be narrowed, and coarse second phase particles will be easily precipitated, and the strength will be slightly improved, but the bending workability will be deteriorated. Difference. At the same time, the coarse second-phase particles contribute to the surface roughness of the curved portion, which promotes die wear during press working. Therefore, as the third element group, it is preferable to contain one or two or more kinds selected from Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B, and P in a total of 0 to 0.5 mass. %, more preferably 0 to 0.2% by mass, still more preferably 0.01 to 0.15% by mass.

The addition of the third element is effective for the refinement of the crystal grains of titanium copper, but on the other hand, the solid solution limit temperature may be raised. Therefore, it is necessary to raise the solid solution temperature compared with the case where the third element is not added. Conventionally, in order to sufficiently dissolve the third element, the final solution treatment is performed after the first solution treatment at a high temperature for a relatively long period of time. However, since the solution treatment is performed twice, a load is imposed on the manufacturing process, and there is a possibility that the production efficiency may decrease. In this embodiment, by adjusting the concentration of the third element in titanium copper to 0 to 0.2% by mass, and more preferably to 0.01 to 0.15% by mass, it is possible to pass the Solution treatment simultaneously carries out solid solution and recrystallization of the third element. Accordingly, the amount of heat required for the production of titanium copper can be reduced compared with conventional ones, and the processing time can also be shortened, so that the production efficiency can be improved, and a process suitable for mass production can be realized.

<Integrated Intensity by X-ray Diffraction>

The aggregate structure of the rolled surface after the solution treatment usually has a high constituent ratio of the (200) plane, which rotates as rolling progresses, and finally the constituent ratio of the (220) plane increases. As a result of research by the present inventors, it was found that the production steps of this embodiment, that is, heat treatment after the final solution treatment and before cold rolling, are different from the conventional steps, that is, solution treatment → cold rolling → aging treatment. Compared with the step, the rotation from the (200) to the (311) plane is not easy to occur due to the modulated structural growth in the base material. Therefore, in the copper alloy of the present embodiment, when measuring the X-ray diffraction intensity (integrated intensity) of the rolled surface, it is preferable that the X-ray diffraction intensity I of the rolled surface is related to the pure copper in the (311) plane and the (200) plane. The ratio (I/I ₀ ) of the X-ray diffraction intensity I ₀ of the powder satisfies the following relational formula (1):

{I/I ₀ (311)}/{I/I ₀ (200)}≤2.54...(1).

In the present invention, pure copper standard powder is defined as the copper powder of the purity 99.5% of 325 orders (JIS Z8801).

More preferably, {I/I ₀ (311)}/{I/I ₀ (200)} is 0.50 to 2.00, and even more preferably {I/I ₀ (311)}/{I/I ₀ (200)} is 0.80 to 1.75. When {I/I ₀ (311)}/{I/I ₀ (200)} exceeds 2.54, the strength (0.2% endurance) becomes weak, and the bending workability may also deteriorate.

The microstructure of titanium copper is also influenced by the processing rate of the final rolling step. That is, if the working ratio of rolling is too large, the (220) plane grows too much and the bendability deteriorates, and if the workability is too low, the growth of the (220) plane is insufficient and the strength may decrease. Titanium copper in this embodiment is preferably performed at a processing rate of 5 to 40%, more preferably 10 to 30%. The aggregate structure of the rolling surface at this time is preferably the ratio (I/I ₀ ) of the X-ray diffraction intensity I of the rolling surface to the X-ray diffraction intensity I ₀ of the pure copper powder in the (220) plane and (200) plane satisfies The following relationship (2):

15≤{I/I ₀ (220)}/{I/I ₀ (200)}≤95...(2).

When {I/I ₀ (220)}/{I/I ₀ (200)} is less than 15, the working rate is low, and the work hardening by the rolling step may become insufficient.

Comparing the aggregate structure of the case where the solution treatment was performed twice and the case where the solution treatment was performed only once, it can be seen that the case where the solution treatment was performed only once was compared with the case where the solution treatment was performed twice. The recrystallized aggregate structure is weak, and the value of the (220)/(200) ratio increases. In obtaining a good balance between strength and flexibility, in addition to relational expression (1), it is more preferable to satisfy the following relational expression (3) instead of relational expression (2):

30≤{I/I ₀ (220)}/{I/I ₀ (200)}≤95...(3),

More preferably, {I/I ₀ (220)}/{I/I ₀ (200)} is 40 to 70, and even more preferably {I/I ₀ (220)}/{I/I ₀ (200)} is 40 ~55.

<purpose>

The copper alloy of this embodiment can be provided in various wrought copper forms such as plate, strip, tube, rod, foil and wire. By processing the copper alloy of this embodiment, electronic components such as switches, connectors, sockets, terminals, and relays can be obtained, for example.

<Manufacturing method>

One feature of the copper alloy of the present embodiment is that heat treatment is performed for a short time under predetermined material temperature conditions after the final solution treatment and before cold rolling. During the heat treatment, if the temperature of the material is too high and the time is too long, the β' phase that does not have such a large effect on the strength and the β phase that deteriorates the bending workability are easily precipitated in the subsequent aging treatment. Also, if the temperature of the material during the heat treatment is too low and the time is too short, the growth of the modulated structure due to spinodal decomposition during the aging treatment tends to be insufficient.

When the titanium copper after solution treatment is heat-treated, the electrical conductivity increases with the growth of the modulated structure, so the degree of annealing can be indexed by the change in electrical conductivity before and after annealing. According to the research of the present inventors, the heat treatment is preferably performed under the condition that the electrical conductivity is increased by 0.5 to 8% IACS, preferably by 1 to 4% IACS. That is, it is preferable to perform heat treatment of less than 90% of the peak hardness here. Specific heat treatment conditions corresponding to such an increase in electrical conductivity are conditions in which the material temperature is 300° C. or higher and lower than 700° C., and heating is performed for 0.001 to 12 hours.

More specifically, in the heat treatment of the present embodiment, when the titanium concentration (mass %) is [Ti], the increase value C (%IACS) of the electrical conductivity can satisfy the following relational expression (4).

0.5≤C≤(-0.50[Ti] ² -0.50[Ti]+14)...(4)

According to the above formula (4), for example, when the Ti concentration is 2.0% by mass, it is preferably carried out under the condition that the electrical conductivity is increased by 0.5 to 11% IACS; It is carried out under the condition of 8% IACS, and when the Ti concentration is 4.0% by mass, it is preferable to carry out under the condition of increasing the electric conductivity by 0.5 to 4% IACS.

More preferably, the heat treatment according to this embodiment satisfies the following relational expression (5) when the titanium concentration (mass %) is [Ti].

1.0≤C≤(0.25[Ti] ² -3.75[Ti]+13)...(5)

According to the above formula (5), for example, when the Ti concentration is 2.0% by mass, it is preferably carried out under the condition that the electrical conductivity is increased by 1.0 to 6.5% IACS; It is carried out under the condition of 4% IACS, and when the Ti concentration is 4.0% by mass, it is preferable to carry out under the condition of increasing the electric conductivity by 1.0 to 2% IACS.

Furthermore, in the heat treatment after the final solution treatment, when the aging of the hardness peak of the copper alloy is performed, the difference in electrical conductivity increases by, for example, 13% IACS at a Ti concentration of 2.0% by mass, and increases by 10% at a Ti concentration of 3.0% by mass. %IACS increased by about 5% IACS at a Ti concentration of 4.0% by mass. That is, in the heat treatment after the final solution treatment in this embodiment, the amount of heat supplied to the copper alloy is very small compared with the aging when the hardness peaks.

The heat treatment is preferably performed under any one of the following conditions.

Material temperature is above 300°C and below 400°C, heating for 0.5 to 3 hours

Material temperature is above 400°C and below 500°C, heating for 0.01 to 0.5 hours

Material temperature is above 500°C and below 600°C, heating for 0.001 to 0.01 hours

The material temperature is above 600°C and below 700°C, heating for 0.001 to 0.005 hours

In addition, heat treatment is more preferably performed under any one of the following conditions.

Material temperature is above 350°C and below 400°C, heating for 1 to 3 hours

Material temperature is above 400°C and below 450°C, heating for 0.2 to 0.5 hours

Material temperature is above 500°C and below 550°C, heating for 0.005 to 0.01 hours

The material temperature is above 550°C and below 600°C, heating for 0.001 to 0.005 hours

The material temperature is above 600°C and below 650°C, heating for 0.0025 to 0.005 hours

A preferred embodiment of each step is described below.

1) Ingot manufacturing steps

Production of ingots by melting and casting is basically performed in a vacuum or in an inert gas atmosphere. If there is a molten residue of the added element during melting, it cannot effectively improve the strength. Therefore, in order to eliminate melting residues, high-melting-point additive elements such as Fe and Cr must be sufficiently stirred after addition and maintained for a certain period of time. On the other hand, Ti can be added after melting of the third element group because it is relatively easy to melt in Cu. Therefore, one or two or more selected from Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B, and P are added to Cu at a total content of 0 to 0.2% by mass. , and then add Ti at a content of 2.0 to 4.0% by mass to manufacture an ingot.

2) Homogenization annealing and hot rolling

Among them, it is preferable to eliminate solidification segregation and crystals generated during casting as much as possible. This is for the purpose of finely and uniformly dispersing the precipitation of the second phase particles in the subsequent solution treatment, and it is also effective for preventing particle mixing. After the ingot manufacturing step, hot rolling is preferably performed after heating to 900 to 970° C. for 3 to 24 hours for homogenization annealing. In order to prevent liquid metal brittleness, it is preferable to set the temperature at 960° C. or lower before hot rolling and during hot rolling.

3) First solution treatment

Then, solution treatment is performed after cold rolling and annealing are repeated appropriately. Specifically, the first solution treatment may be performed at a heating temperature of 850-900° C. for 2-10 minutes. At this time, the heating rate and cooling rate are preferably accelerated as much as possible so that the second-phase particles do not precipitate. However, when the addition amount of the third element is 0.01 to 0.15% by mass, solid solution and recrystallization can be performed only through the final solution treatment without the first solution treatment, so it is preferable to omit the first solution treatment step .

4) Intermediate rolling

The higher the degree of processing in the intermediate rolling before the final solution treatment, the more uniform and finely precipitated the second phase particles in the final solution treatment. However, if the degree of processing is too high, the recrystallized aggregate structure will grow during the final solution treatment, resulting in plastic anisotropy, which may impair the pressure plasticity. Therefore, the working degree of intermediate rolling is preferably 70 to 99%. The workability is defined as {(thickness before rolling−thickness after rolling)/thickness before rolling)×100%}.

5) Final solution treatment

Precipitates generated during casting or intermediate rolling exist in the copper alloy raw material before final solution treatment. Since the precipitates may hinder the increase in flexibility and mechanical properties after aging, it is preferable to heat the copper alloy raw material to a temperature at which the precipitates in the copper alloy raw material are completely dissolved in the final solution treatment. However, when heating to high temperature until the precipitates completely disappear, the locking effect of the grain boundaries by the precipitates disappears, and the crystal grains rapidly coarsen. When the crystal grains are rapidly coarsened, the strength tends to decrease.

Therefore, as the heating temperature, the copper alloy raw material before solid solution is heated to a temperature close to the solid solution limit of the second phase particle composition. When the addition amount of Ti is in the range of 2.0 to 4.0% by mass, the temperature at which the solid solution limit of Ti is equal to the addition amount (referred to as "solution limit temperature" in the present invention) is about 730 to 840°C. For example, the addition amount of Ti When it is 3.0% by mass, it is about 800°C. Furthermore, if the temperature is rapidly heated to the temperature and the cooling rate is also increased, the generation of coarse second-phase particles is suppressed. Therefore, it is typically heated to a temperature above which the solid solution limit of Ti at 730 to 880°C is the same as the added amount, and more typically heated to a temperature at which the solid solution limit of Ti at 730 to 880°C is the same as the added amount. A temperature of 0 to 20°C higher, preferably a temperature of 0 to 10°C higher.

In order to suppress the generation of coarse second-phase particles in the final solution treatment, it is preferable to perform heating and cooling of the copper alloy raw material as quickly as possible. Specifically, rapid heating is performed by arranging the copper alloy raw material in an atmosphere that is about 50 to 500°C higher than the temperature of the solid solution limit of the second phase particle composition, preferably about 150 to 500°C higher. Cooling is performed by water cooling or the like.

6) Heat treatment

Heat treatment is performed after the final solution treatment. The conditions of the heat treatment are as described above.

7) Final cold rolling

After the above annealing, final cold rolling is performed. Through the final cold working, the strength of titanium copper can be improved. At this time, if the working degree is less than 5%, sufficient effect cannot be obtained, so it is preferable to make the working degree 5% or more. However, if the processing is too high, the processing deformation due to the flattening of crystal grains will increase compared with the lattice deformation due to intragranular precipitation, and the bending workability will deteriorate. Furthermore, grain boundary precipitation tends to occur in aging treatment and stress relief annealing performed as needed, so the workability is 40% or less, preferably 5-40%, more preferably 10-30%, and still more preferably 15-25%.

8) Aging treatment

Aging treatment is performed after the final cold rolling. The conditions of the aging treatment may be conventional conditions, but if the aging treatment is performed lightly compared with conventional ones, the balance between strength and bendability will be further improved. Specifically, the aging treatment is preferably carried out under conditions of heating at a material temperature of 300 to 400° C. for 3 to 12 hours. Furthermore, when no aging treatment is performed, when the aging treatment time is short (less than 2 hours), or when the aging treatment temperature is low (less than 290° C.), the strength and electrical conductivity may decrease. In addition, when the aging time is long (13 hours or more) or the aging temperature is high (450° C. or more), the electrical conductivity increases, but the strength may decrease.

The aging treatment is more preferably performed under any one of the following conditions.

Material temperature is above 340°C and below 360°C, heating for 5-8 hours

Material temperature is above 360°C and below 380°C, heating for 4 to 7 hours

Material temperature is above 380°C and below 400°C, heating for 3 to 6 hours

The aging treatment is more preferably performed under any one of the following conditions.

Material temperature is above 340°C and below 360°C, heating for 6-7 hours

Material temperature is above 360°C and below 380°C, heating for 5-6 hours

Material temperature is above 380°C and below 400°C, heating for 4 to 6 hours

Moreover, those skilled in the art can understand that steps such as grinding, polishing, and shot-blasting pickling for removing surface scale can be appropriately performed between the above-mentioned steps.

[Example]

Examples and comparative examples of the present invention will be described below, but these examples are provided for better understanding of the present invention and its advantages, and are not intended to limit the invention.

When producing the copper alloy of the example of the present invention, active metal Ti is added as the second component, so a vacuum melting furnace is used for melting. In addition, in order to prevent unexpected side effects due to the incorporation of impurity elements other than those specified in the present invention, raw materials with relatively high purity are strictly selected and used.

After adding the third element in Table 1 to Cu as needed, Ti in the concentration shown in Table 1 was added, and the remainder had copper and unavoidable impurities, after performing homogenization annealing by heating at 950°C for 3 hours , hot-rolled at 900-950° C. to obtain a hot-rolled sheet with a thickness of 10 mm. After descaling by surface grinding, cold rolling is performed to form a billet with a thickness of 1.5mm, and the first solution treatment of the billet is performed as needed (according to the addition amount of the third element). The condition of the first solution treatment is heating at 850° C. for 7.5 minutes. Next, in the intermediate cold rolling, the intermediate plate thickness is adjusted and cold rolled so that the final plate thickness is 0.25 mm, and then inserted into an annealing furnace capable of rapid heating for final solution treatment, and then water cooled. The heating conditions at this time are such that the solid solution limit of Ti is the same temperature as the added amount (about 800°C when the Ti concentration is 3.2% by mass, about 730°C when the Ti concentration is 2.0% by mass, and about 840°C) as a reference, the heating conditions described in Table 1 were maintained for 1 minute to form conditions 0 to 20°C higher than the temperature at which the solid solution limit of Ti was the same as the addition amount.

Next, after cold rolling under the conditions described in Table 1 using the test piece, heat treatment was performed under the conditions described in Table 1 in an Ar atmosphere. After descaling by pickling, final cold rolling was performed under the conditions described in Table 1, and finally aging treatment was performed under each heating condition described in Table 1 to form test pieces of Examples and Comparative Examples.

[Table 1]

About each obtained test piece, characteristic evaluation was performed under the following conditions. The results are shown in Table 2.

<strength>

A JIS No. 13B test piece was manufactured using a press machine so that the stretching direction was parallel to the rolling direction. The tensile test of this test piece was performed according to JIS-Z2241, and the 0.2% proof strength (YS) in the rolling direction was measured.

<Bending Workability>

According to JIS H3130, the W bending test of Badway (the bending axis and the rolling direction are in the same direction) is carried out, and the ratio MBR/t value of the minimum radius (MBR) without cracks to the plate thickness (t) is measured.

<Conductivity>

According to JIS H 0505, the electrical conductivity (EC: %IACS) was measured by the 4-terminal method.

<Crystal Orientation>

For each test piece, using an X-ray diffraction apparatus manufactured by Rigaku Corporation, model rint Ultima 2000, the diffraction intensity curve of the rolled surface was obtained under the following measurement conditions, and the (111) crystal plane, (200) crystal plane, (220) crystal plane were measured. X-ray diffraction intensity (integrated value) I of crystal plane and (311) crystal plane. Under the same measurement conditions, for pure copper powder standard samples, also obtain X-ray diffraction intensity (integral value) I for (111) crystal plane, (200) crystal plane, (220) crystal plane, (311) crystal plane ₀ , respectively calculate I/I ₀ (111), I/I ₀ (200), I/I ₀ (220), I/I ₀ (311), and obtain {I/I ₀ (311)}/{I /I ₀ (200)} and {I/I ₀ (220)}/{I/I ₀ (200)}.

Target: Cu tube ball

Tube voltage: 40kV

Tube current: 40mA

Scanning speed: 5°/min

Sampling width: 0.02°

[Table 2]

<investigation>

Comparative Examples 1 to 5 show that the added element of the third element is 0 to 0.17% by mass, the final solution treatment is performed only once without the first solution treatment, and the final solution treatment→cold rolling→aging treatment is followed. Example of manufacturing in the previous steps. In Comparative Examples 1 to 5, sufficient strength was not obtained.

Comparative Examples 6 to 10 show that the added element of the third element is 0 to 0.17% by mass, two-stage solution treatment (the first solution treatment and the final solution treatment) is performed, and the final solution treatment → cold rolling → An example of the conventional steps of aging treatment at the time of manufacture. In Comparative Examples 5 to 10, although the bendability was improved, sufficient strength was not obtained.

Comparative Example 11 shows an example in which the degree of working during cold rolling was excessively reduced when manufacturing in the order of final solution treatment→heat treatment→cold rolling→aging treatment. In Comparative Example 11, sufficient strength could not be obtained because the working was too low.

Comparative Example 12 shows an example in which the degree of working during cold rolling is excessively increased when the steel sheet is produced in the steps of final solution treatment→heat treatment→cold rolling→aging treatment. In Comparative Example 12, although sufficient strength was obtained, bendability deteriorated due to excessive processing.

Comparative Example 13 shows that when manufacturing according to the steps of final solution treatment→heat treatment→cold rolling→aging treatment, the final solution treatment is carried out under the condition (peak aging condition) where the hardness of titanium copper is close to the peak, and then in a very short time Example of final aging treatment. In Comparative Example 13, since the heat treatment after solutionization was in the vicinity of the peak, a coarse stable phase precipitated and the bendability deteriorated.

Compared with Comparative Examples 1 to 13, it can be seen that in Examples 1 to 11, the strength and bending workability are well-balanced and improved.

Claims (6)

1. copper alloy, it is the Ti containing 2.0 ~ 4.0 quality %, amount to containing 0 ~ 0.2 quality % as the 3rd element to be selected from Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B and P one kind or two or more, remainder comprises the copper alloy of copper and inevitable impurity, wherein, when measuring the X-ray diffraction intensity of rolling surface

The X-ray diffraction intensity I of rolling surface and the X-ray diffraction intensity I of the fine copper powder in (311) face and (200) face ₀ratio (I/I ₀) meet following relational expression (1):

{I/I ₀(311)}/{I/I ₀(200)}≤2.54…(1)，

And the X-ray diffraction intensity I of fine copper powder in the X-ray diffraction intensity I of rolling surface and (220) face and (200) face ₀ratio (I/I ₀) meet following relational expression (2):

15≤{I/I ₀(220)}/{I/I ₀(200)}≤95…(2)。

2. copper alloy, it is the Ti containing 2.0 ~ 4.0 quality %, amount to containing 0.01 ~ 0.15 quality % as the 3rd element to be selected from Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B and P one kind or two or more, remainder comprises the copper alloy of copper and inevitable impurity, wherein, when measuring the X-ray diffraction intensity of rolling surface

The X-ray diffraction intensity I of rolling surface and the X-ray diffraction intensity I of the fine copper powder in (311) face and (200) face ₀ratio (I/I ₀) meet following relational expression (1):

{I/I ₀(311)}/{I/I ₀(200)}≤2.54…(1)，

And the X-ray diffraction intensity I of fine copper powder in the X-ray diffraction intensity I of rolling surface and (220) face and (200) face ₀ratio (I/I ₀) meet following relational expression (3):

30≤{I/I ₀(220)}/{I/I ₀(200)}≤95…(3)。

3. forged copper, it comprises the copper alloy described in claim 1 or 2.

4. electronic component, it comprises the copper alloy described in claim 1 or 2.

5. connector, it has the copper alloy described in claim 1 or 2.

6. the manufacture method of the copper alloy described in claim 1 or 2, it comprises for the Ti containing 2.0 ~ 4.0 quality %, amount to containing 0 ~ 0.2 quality % as the 3rd element to be selected from Mn, Fe, Mg, Co, Ni, Cr, V, Nb, Mo, Zr, Si, B and P one kind or two or more, remainder comprises the copper alloy raw material of copper and inevitable impurity

Described copper alloy raw material is carried out at 730 ~ 880 DEG C be heated to the solid solution limit temperature of temperature high 0 ~ 20 DEG C more identical with addition than the solid solution limit of Ti and the solutionizing process of quenching,

After solutionizing process, heat-treat,

Carry out finally cold rolling with the working modulus of 5 ~ 40% after the heat treatment,

Ageing Treatment is carried out after finally cold rolling,

Wherein, described heat treatment makes electrical conductivity raise, and when titanium concentration (quality %) is [Ti], makes the rising value C (%IACS) of electrical conductivity meet following relational expression (4):

0.5≤C≤(－0.50[Ti] ²－0.50[Ti]＋14)…(4)。