JP2014098187A - Copper-titanium-hydrogen alloy and method for producing the same - Google Patents

Abstract

The present invention provides a copper-titanium-hydrogen alloy having high strength, high conductivity, and good bending workability, and a method for producing the same.
Copper-titanium is added at 100 at. % Titanium at 1 at. % Or more, 7.5 at. % Or less, and hydrogen is added at 0.1 at. % Of copper and titanium-hydrogen alloy containing less than twice the content of titanium (at% conversion), the X-ray diffraction integrated intensity of {220} crystal plane on the alloy surface is I {220}, and pure copper standard powder When the X-ray diffraction integral intensity of the {220} crystal plane is I ₀ {220}, the crystal has a crystal orientation satisfying I {220} / I ₀ {220} ≦ 3.0, and the width of the twin of the parent phase The copper-titanium-hydrogen alloy has an average of 10 nm or less, a twin density of 30 lines / μm or more, and a titanium-hydrogen compound.
[Selection figure] None

Description

  The present invention relates to a copper-titanium-hydrogen alloy excellent in conductivity and strength and a method for producing the same.

  A copper-beryllium (Cu-Be) alloy having a good balance between electrical conductivity and strength is widely used for energizing contact members such as lead frames and connectors used in electrical and electronic devices. However, since beryllium (Be) is a rare metal and a harmful substance, an alternative to a Cu-Be alloy is desired. The candidate is an aging precipitation type copper-titanium (Cu-Ti) alloy. The copper-titanium alloy is given mechanical properties comparable to the copper-beryllium alloy by aging, and high conductivity can be expected by aging in hydrogen (Non-patent Document 1).

Strengthening of aging precipitation type copper-titanium alloy is caused by fine and high density dispersion of copper and titanium compound (Cu ₄ Ti) or titanium and hydrogen compound (TiH ₂ ) with aging in hydrogen. . The increase in conductivity is attributed to the fact that the TiH ₂ phase precipitates in addition to the Cu ₄ Ti phase with aging in hydrogen, and as a result, the titanium concentration in the matrix phase is significantly reduced. Previous studies have shown that aging time is required by lowering the aging temperature, but maximum hardness and electrical conductivity at that time are increased (Non-Patent Document 2). However, when the aging temperature is lowered, a long aging time is required to improve the characteristics. For example, when aging in a hydrogen atmosphere with a hydrogen partial pressure of 0.08 MPa, it takes 360 hours at 400 ° C. to achieve 30% IACS with the same strength as normal (not in hydrogen) aging. (Non-patent document 2).

  Patent Document 1 discloses a copper-titanium-hydrogen alloy whose conductivity is improved by aging precipitation hardening of a supersaturated solid solution Cu-Ti alloy in a hydrogen atmosphere. This Patent Document 1 describes that the aging time for drawing out the highest characteristic (balance between tensile strength and electrical conductivity) is about 5 hours, and the hydrogen partial pressure of the aging treatment at this time is about 20 to 30 MPa. (Patent Document 2, paragraphs [0031], [0044], [0045]).

  Patent Document 2 discloses that a copper-titanium alloy cold-rolled at a rolling rate of 10% or more after solution treatment is subjected to aging treatment in a hydrogen atmosphere at a hydrogen partial pressure of 7.5 MPa for approximately 50 hours or more to precipitate and harden, A copper-titanium-hydrogen alloy having high strength and high conductivity in a relatively short time is disclosed. Moreover, there is no description about the structure of the alloy such as the dispersion state of the precipitate phase.

JP 2008-75174 A JP 2010-70825 A

S. Semboshi, T J. Konno, J. Mater. Res. 23, 473-477 (2008). Sensei Azusa, Nishida Tomoya, Numakura Hiroshi, T. Al-Kassaab and R. Kirchheim, Copper and Copper Alloys, 48 (2009), 86-91.

As described above, it is known that Cu ₄ Ti and TiH ₂ are deposited to increase the strength and conductivity, but a high-pressure hydrogen atmosphere or a long-term aging treatment is required. In the “High Pressure Gas Safety Law”, the definition of high pressure gas is 1 MPa or more, and special equipment is restricted when high pressure gas is used. On the other hand, in the aging treatment for several hundred hours, it is practically difficult to industrially mass-produce from the viewpoint of (equipment and cost).

  An object of the present invention is to provide a copper-titanium-hydrogen alloy having high strength and high conductivity, and a manufacturing method capable of manufacturing in a low-pressure hydrogen atmosphere in a short time.

The present invention relates to copper-titanium at 100 at. % Titanium at 1 at. % Or more, 7.5 at. % Or less, and further copper-titanium-hydrogen at 100 at. % Hydrogen at 0.1 at. % Of copper and titanium-hydrogen alloy containing less than twice the content of titanium (at% conversion), the X-ray diffraction integrated intensity of {220} crystal plane on the alloy surface is I {220}, and pure copper standard powder When the X-ray diffraction integral intensity of the {220} crystal plane is I ₀ {220}, the crystal has a crystal orientation satisfying I {220} / I ₀ {220} ≦ 3.0, and the width of the twin of the parent phase The copper-titanium-hydrogen alloy has an average of 10 nm or less, a twin boundary density of 30 lines / μm or more, and a titanium-hydrogen compound. The density of twin boundaries is more preferably 40 lines / μm or more. The pure copper standard powder is a commercially available pure copper standard powder, and is a 325 mesh (JIS Z8801) purity 99.5% copper powder.

  It is preferable that a copper-titanium compound or a titanium-hydrogen compound having a size of 10 nm or less is present at the twin interface, and it is preferable that the tensile strength is 950 MPa or more and the conductivity is 15% IACS or more. In addition, it is more preferable that the tensile strength is 960 MPa or more, and the conductivity is 18% IACS or more, and it is more preferable that the conductivity is 20% IACS or more. Further, the ratio R / t of the minimum bending radius R to the plate thickness in the 90 ° W bending test may be 2.0 or less. The copper-titanium-hydrogen alloy of the present invention further comprises 100 at. %. At. %, Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1.0% or less Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2.0% or less You may contain 1 or more types.

  In the present invention, copper-titanium is added at 100 at. % Titanium at 1 at. % Or more, 7.5 at. %, And after the solution treatment of the copper-titanium alloy having the composition of the remaining copper and unavoidable impurities, a pre-aging treatment for precipitating a copper-titanium compound is performed, and then cold rolling is performed, This is a method for producing a copper-titanium-hydrogen alloy that is subjected to an aging treatment in a hydrogen atmosphere.

  The rolling rate of the cold rolling is preferably 30% or less, and the preliminary aging treatment is preferably performed at a temperature range of 300 to 500 ° C. for 5 to 240 minutes, more preferably 10 to 50 minutes, The aging treatment temperature in the hydrogen atmosphere is preferably performed in the range of 300 to 400 ° C. The copper-titanium alloy may be copper-titanium at 100 at. %, And at. %, Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1.0% or less Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2.0% or less A copper-titanium alloy containing one or more kinds can be solution-treated.

According to the present invention, a high-density copper-titanium compound (Cu ₄ Ti) or a titanium-hydrogen compound (TiH ₂ ) can be preferentially finely precipitated on the twin interface in a short time compared to the conventional case. It is possible to obtain a copper-titanium-hydrogen alloy excellent in conductivity and strength in a short time.

2 is a TEM (Transmission Electron Microscope) photograph of Reference Example 1. It is a TEM (transmission electron microscope) photograph of Comparative Examples 1-3. It is a schematic diagram of the structure | tissue which has a twin crystal.

Embodiments of the present invention will be described below.
In the copper-titanium-hydrogen alloy of the present invention, copper-titanium (total amount of copper and titanium) is 100 at. % Titanium at 1 at. % Or more, 7.5 at. %, And further copper-titanium-hydrogen (total amount of copper, titanium and hydrogen) at 100 at. % Hydrogen at 0.1 at. % Of the content of titanium and not more than twice the content of titanium (at% conversion), and the composition is the balance copper and inevitable impurities. Preferably, the titanium is copper-titanium at 100 at. %, 1.0 at. % To 6.0 at. %. Preferably, the hydrogen content is 1.7 times or less (at.% Conversion) of titanium content. Moreover, the copper-titanium-hydrogen alloy of the present invention contains copper-titanium at 100 at. %, And at. %, Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1.0% or less Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2.0% or less 1 or more types can be contained. Throughout the specification and claims, “copper-titanium-hydrogen alloy” means a Cu—Ti—H alloy including an alloy to which elements such as Zr and Cr are added, and “at.% "Means the atomic abundance ratio (atomic%: atomic percent).

  The copper-titanium-hydrogen alloy of the present invention was processed at a rolling rate of 30% or less after pre-aging a supersaturated solid solution copper-titanium alloy obtained by super-saturating titanium in copper as a base material and quenching. After that, for example, by heat-treating in a hydrogen atmosphere, the titanium-hydrogen compound is aged to contain hydrogen.

  First, in addition to copper and titanium or copper and titanium, at least one of Zr, Cr, Mg, Ni, Fe, Co, Si, Sn, Mn, V, P, and Zn is melted.

In order to increase the strength of the copper-titanium-hydrogen alloy after production, it is preferable to finely precipitate the Cu ₄ Ti compound phase as densely as possible. The titanium content is 1.0 at. If it is less than%, it is difficult to sufficiently bring out the strengthening action by the compound phase. The titanium content is 7.5 at. If it exceeds C%, Cu ₄ Ti tends to form coarsely in the supersaturated solid solution obtained by rapid cooling, and cracks are likely to occur in subsequent hot and cold working, leading to a decrease in productivity. . Therefore, the titanium content is 1.0 at. % To 7.5 at. %, 1.0 at. % To 6.0 at. %, Preferably in the range of 2.0 at% to 5.0 at%.

Since copper-titanium alloys are susceptible to Cu ₄ Ti discontinuous precipitation (grain boundary reaction precipitation), the effect of suppressing grain boundary reaction precipitation by adding a small amount of Zr, Cr, Mg, Ni, Fe, Co. There is. However, this element tends to segregate at the grain boundary, and if the addition amount is too high, the castability, hot and cold workability are reduced. If necessary, copper-titanium is added at 100 at. %: Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1. It is preferable to add 0% or less. Moreover, since the effect which suppresses the said grain boundary reaction precipitation is small when there are too few each of these elements, the minimum of each of these elements is 0.01 at. % Or more is preferable.

As described in detail later, the copper-titanium-hydrogen alloy of the present invention has a large amount of deformation twins before aging in order to suppress the refinement or coarsening of the titanium-hydrogen compound (TiH ₂ ) during aging. Introduction is necessary. Therefore, it is effective to add an element having an effect of reducing stacking fault energy of the copper matrix phase, Si, Sn, Mn, V, P, and Zn. However, if the amount of the element added is too high, the conductivity is reduced. If necessary, copper-titanium is added at 100 at. %: Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2 It is preferable to add one or more of 0.0% or less. Further, if these elements are too small, the effect of lowering the stacking fault energy of the copper matrix phase is small, so these elements are at least 0.01 at. % Or more is preferable.

  For melting, a commonly used method such as an alloy melting method or an argon arc melting method can be used. In addition, since titanium has a high vapor pressure, the composition hardly changes during melting. Therefore, a copper-titanium alloy having a predetermined composition can be obtained by charging the material with a target charging amount.

  The rapid cooling after melting is performed for the purpose of obtaining a supersaturated solid solution (supersaturated solid solution) in copper. Specific examples of the rapid cooling include water cooling, oil cooling, and air cooling. However, it is only necessary to maintain the supersaturated solid solution state, and the present invention is not limited to these. In addition, the rapid cooling is preferably performed by increasing the specific surface area relative to the volume as much as possible. This is because even if it is rapidly cooled in a state where the specific surface area is small, the temperature does not decrease easily and there is a possibility that it cannot be rapidly cooled uniformly.

  The ingot obtained in this way is preferably subjected to hot rolling, cold rolling or the like as necessary in order to obtain a desired thickness, for example. Further, after the hot rolling or cold rolling, it is preferable to perform a solution treatment for re-solution and recrystallization of the solute element in the matrix to homogenize the structure. However, since the material after the solution treatment is soft, deformation twinning hardly occurs in the subsequent cold rolling. Therefore, in the present invention, after the solution treatment, a preliminary aging treatment (heat treatment) is performed, followed by cold rolling at a low rolling rate, and then aging treatment in a hydrogen atmosphere.

  In the pre-aging treatment, a predetermined amount of the precipitate (copper-titanium compound) is precipitated from the matrix. After the preliminary aging treatment, the hardness increases due to the presence of precipitates, but the next step of cold rolling is performed in a state where the hardness is high. By performing cold rolling after the preliminary aging treatment, it is understood that twins having a small width are likely to be generated even if the rolling rate is low. Specifically, the rolling rate is preferably 30% or less, more preferably 20% or less, and a copper alloy having a predetermined twin density with a small twin width can be obtained.

In the preliminary aging treatment, it is not necessary to deposit a large amount of precipitates. Specifically, the heat treatment is performed at a temperature range of 300 to 500 ° C. for 5 to 240 minutes, and further 10 to 50 minutes (preliminary aging treatment). It is more preferable to carry out.
Further, in the preliminary aging treatment, although the amount of precipitates generated at a relatively low temperature or in a short time is small, it is finely and uniformly dispersed, and “nuclear” of precipitates precipitated during the subsequent aging treatment in a hydrogen atmosphere. The aging time for drawing out the highest properties (balance between tensile strength and conductivity) can be greatly shortened.

  Thereafter, introduction of hydrogen into the copper-titanium alloy is performed, for example, by performing an aging treatment in a hydrogen atmosphere. This aging treatment is a technique in which heat treatment is performed in an atmosphere where the hydrogen pressure is atmospheric or pressurized. The aging treatment atmosphere is preferably performed by reducing the pressure once and then introducing hydrogen gas to create a reducing atmosphere.

  In addition, since the alloy structure changes due to factors such as the composition of the copper-titanium alloy, hydrogen concentration, hydrogen pressure, processing temperature, and processing time, the conditions for aging treatment in a hydrogen atmosphere cannot be specified uniformly. It is preferable to narrow down processing conditions for each manufacturing purpose. As an example, in the present application, the hydrogen partial pressure is about 1.0 MPa or less, preferably 0.8 MPa or less, the aging treatment (annealing) temperature is in the range of 300 to 400 ° C., and preferably 380 ° C. or less. In addition, although the aging treatment time depends on the intended characteristics, it is preferably 24 h or less, more preferably 12 h or less when operating in a factory or the like.

The hydrogen content after age precipitation hardening can be contained up to twice the titanium content. This is because the introduced hydrogen is taken in the form of titanium hydride (TiH ₂ ) with respect to titanium in the copper-titanium alloy.

In the copper-titanium-hydrogen alloy of the present invention, copper-titanium-hydrogen is added at 100 at. %, The hydrogen content is 0.1 at. % Or more and 1.7 at. % Or more is preferable and is not more than twice the titanium content. 0.1 at. If it is less than%, it is difficult to achieve both conductivity and strength. If hydrogen exceeds twice the titanium content, excess hydrogen will be in a free state, and the bending workability of the plate will be significantly deteriorated, so that it will be twice as much. did. Further, as described above, since hydrogen is taken in the form of titanium hydride (TiH ₂ ) with respect to titanium in the copper-titanium alloy, the hydrogen content is preferably up to twice the titanium content, 0.7 or less is preferable.

  When aging precipitation hardening is carried out in hydrogen, strength and electrical conductivity are exhibited, and therefore, it may be molded into a product or the like before aging treatment.

  By this aging treatment, a titanium-copper compound or a titanium hydride compound is formed at a high density using lattice defects such as dislocations and twins as nucleation sites. For this reason, electrical conductivity can be improved rapidly, without reducing intensity | strength almost. In addition, as above-mentioned, it is preferable to implement in the range whose aging heat processing temperature in a hydrogen atmosphere is 300-400 degreeC.

Moreover, since the rolling rate after the preliminary aging treatment is small, the rolling texture does not develop excessively, and good bending workability can be maintained. The main orientation of the rolled texture of the copper alloy is the brass orientation, and in the case of X-ray diffraction measurement, it can be expressed by the X-ray diffraction integrated intensity of the {220} orientation. The amount of the rolling texture can be expressed by the strength of the X-ray diffraction integral intensity, I {220} / I ₀ {220}. Here, the X-ray diffraction integral intensity of the {220} crystal plane on the surface of the plate is I {220}, and the X-ray diffraction integral intensity of the {220} crystal plane of the pure copper standard powder is I ₀ {220}. The higher I {220} / I ₀ {220}, which is the ratio of the X-ray diffraction integrated intensity between the surface of the plate material and the pure copper standard powder, the worse the bending workability, so 3.0 or less, and 2.3 or less 2.0 or less.
Specifically, as described above, the pre-aging treatment is 300 to 400 ° C. and 10 to 50 minutes, and the rolling rate is 20% or less, so that the strength and conductivity are high and the bending workability is also excellent. A copper-titanium-hydrogen alloy can be obtained.

In addition, the copper-titanium-hydrogen alloy of the present invention introduces twins having a small width by performing cold rolling at a low rolling rate after the preliminary aging treatment, and then the twinning interface by aging treatment in a hydrogen atmosphere. The point is that Cu ₄ Ti and TiH ₂ are preferentially precipitated on top. Twins introduced into the copper-titanium alloy can be observed with a transmission electron microscope. Further, Cu ₄ Ti and TiH ₂ after aging in hydrogen can also be observed with a transmission electron microscope. In a reference example and a comparative example described later, a transmission electron microscope was used to measure twin plane spacing (width), twin boundary density, formation phase identification, dispersion state, and the like.

In the copper-titanium-hydrogen alloy of the present invention, the content of titanium and hydrogen is one of the important control parameters. A general analytical method can be applied to confirm these contents. For example, the content of titanium is determined by X-ray diffractometer, energy dispersive X-ray fluorescence analyzer, wavelength dispersive X-ray fluorescence analyzer, ICP-AES (Inductively
(Coupled Plasma Atomic Emission Spectrometer) method can be used. The ICP-AES method is a suitable quantitative measurement because it can measure not only the surface layer portion of the sample but also the entire sample. In this method, a measurement sample is completely dissolved in a solution, the solution is combusted with plasma, and an element in the sample is once converted into an excited ion state. In this method, the element is identified from the wavelength of the emission spectrum emitted when the excited state is deactivated to the state of lower energy, and quantitative analysis is performed from the emission intensity. In this method, it is necessary to make a sample into a solution, but in the case of a copper-titanium alloy, a nitric acid solution or the like is used. There are also commercially available measuring devices, for example, IRIS-Advantage made by Thermo-element.
There are DUO and the like, and in the examples and comparative examples described later, this was used for measurement.

  Further, the hydrogen content can be measured by an argon gas transport melting-heat conduction method. This is a method in which a sample is melted, gas elements such as hydrogen and nitrogen are generated from the sample, and the thermal conductivity of the mixed gas is measured. Each gas exhibits different thermal conductivity. It is a method of using and quantifying component elements. There are various types of measurement methods depending on whether the sample is melted in an inert gas or in an oxygen residual atmosphere. Either method may be used. There are also commercially available devices such as EMGA-621 “High Sensitivity Hydrogen Analyzer” manufactured by HORIBA, Ltd.

  Pure copper (99.99%) and pure titanium (99.99%) were melted in an argon gas atmosphere, and the alloy composition was 4.2 at. A copper-titanium alloy ingot composed of% Ti-remainder Cu and inevitable impurities was produced. The ingot was rolled to a thickness of 0.22 mm and then held at 880 ° C. for 24 hours in a vacuum for solution treatment, and then quenched in ice water to obtain a test piece after solution treatment. Thereafter, preliminary aging was performed in vacuum at 450 ° C. for 30 minutes.

  Then, the sample of Reference Example 1 was obtained by cold rolling at a rolling rate of 10%. Moreover, the preliminary aging was not performed, and cold rolling was performed at a rolling rate of 15% (Comparative Example 1), 30% (Comparative Example 2), and 60% (Comparative Example 3) to obtain a sample of a comparative example.

  Next, the sample of the comparative example was aged at a temperature of 380 ° C. in hydrogen. The hydrogen pressure was 0.8 MPa.

  Next, the sample of the comparative example was taken out in advance by the aging curve (hardness-aging time) and after the aging treatment at the time when the peak hardness was reached, each sample was taken out and left to cool by air. Specific hydrogen aging times were 48 hours for Comparative Examples 1 and 2 and 6 hours for Comparative Example 3, respectively.

  The strength of each sample completed was obtained by taking a test piece for a tensile test in the rolling direction of a copper alloy material and performing a tensile test based on JIS Z 2241 to obtain a tensile strength. The conductivity was converted by measuring the resistance value by the four probe method. The conductivity notation was converted to “% IACS” based on the conductivity of the standard annealed copper wire.

X-ray diffraction intensity (X-ray diffraction integrated intensity) is measured by preparing samples whose plate surfaces (rolled surfaces) are polished with # 1500 water-resistant paper and using an X-ray diffractometer (XRD). The measurement was performed by measuring the X-ray diffraction intensity I {220} of the {220} plane of the polished surface of the sample under the conditions of -Kα ray, tube voltage 40 kV, and tube current 30 mA. On the other hand, using the same X-ray diffractometer, the X-ray diffraction intensity I ₀ {220} of the {220} plane of pure copper standard powder was measured under the same measurement conditions. Using these measured values, the X-ray diffraction intensity ratio I {220} / I ₀ {220} was determined.

  In the present invention, the twin boundary density and the average twin width are obtained by taking a photograph of each sample with a transmission electron microscope (TEM) and measuring the length perpendicular to the twin boundary (straight line). The number of twin boundaries (straight lines) intersecting the 300 nm line segment is counted, and the density of the twin boundary is calculated per 1 μm. The line in the twin region detected in the line segment The length of each minute was measured as the twin width, and the average of the widths was taken as the average twin width.

  Moreover, as Examples 1-5, about the test piece after the solution treatment of Reference Example 1, the preliminary aging treatment was performed at 450 ° C. for 180 minutes, and then cold rolling was performed at a rolling rate of 15%. . Thereafter, the hydrogen pressure was set to 0.8 MPa, and the aging treatment in a hydrogen atmosphere was conducted at 350 ° C. for 96 hours, Example 2 at 350 ° C. for 24 hours, Example 3 at 380 ° C. for 6 hours, Example 4 Was aging at 380 ° C. for 12 hours, and Example 5 was hydrogen aging at 380 ° C. for 24 hours. The electrical conductivity, tensile strength, and Vickers hardness of the obtained test piece were measured.

The measurement results are shown in Table 1.

Since the rolling rate of Reference Example 1 was 10%, which was close to Comparative Example 1 having a rolling rate of 15%, it was almost equivalent I {220} / I ₀ {220}. However, since Reference Example 1 was subjected to preliminary aging, it was found that even at a small rolling rate, the twin boundary density was high and the twin width was small.
In each of Examples 1 to 5, the electrical conductivity exceeded 15% IACS, the Vickers hardness Hv was 310 or more, and in Examples 1 and 3, the tensile strengths were 969 MPa and 960 MPa, respectively. That is, it was found that both high conductivity and high strength are compatible. In Examples 1 to 5, the hydrogen aging time is evaluated from 6 to 96 hours. However, if it is 24 hours or less as in Examples 2 to 5, for example, it can be easily incorporated into a normal production process. Since the hydrogen pressure is relatively low, the production process of the present invention is a condition that can be industrialized sufficiently. Fine Cu ₄ Ti and TiH ₂ precipitates were observed on the twin interface.
On the other hand, in Comparative Examples 1 and 2, the conductivity is 15% IACS or less, the Vickers hardness is 295 and 297, the tensile strength is 880 MPa and 932 MPa, respectively. Greatly inferior. In Comparative Example 3, the Vickers hardness Hv is as high as 313 and the tensile strength is as high as 982 MPa, but the electrical conductivity is as low as 12.0% IACS, and the strength and the electrical conductivity are not compatible.
As described above, after solution heat treatment, preliminary aging treatment, cold rolling at a rolling rate of 30% or less, and aging annealing in a hydrogen atmosphere, copper having high conductivity and high strength (hardness) in a short time. -It was confirmed that a titanium-hydrogen alloy can be easily obtained industrially.

  In order to clarify the twin width measurement method, TEM (transmission electron microscope) photographs taken for measurement are shown in FIGS. FIG. 3 shows a schematic diagram of a structure having twins. FIG. 1 shows the twin structure of Example 1. FIG. 2 shows those of Comparative Examples 1 to 3 in which the processing rates (cold rolling rate) after rolling and aging treatment in a hydrogen atmosphere were 15%, 30%, and 60%, respectively. In FIG. 3, B is the twin width. As is known, twin and matrix regions appear alternately. The interface between the twin and the parent phase is the twin boundary.

  Note that copper-titanium-hydrogen was added at 100 at. %, The hydrogen concentration in Example 1 was about 0.58 at%, Example 2 was about 0.13 at%, Example 3 was about 0.12 at%, and Example 4 was about 0.38 at%. Example 5 is about 0.24 at%, Comparative Example 1 is about 0.05 at%, Comparative Example 2 is about 0.07 at%, and Comparative Example 3 is about 0.04 at%.

  The copper-titanium-hydrogen alloy obtained by the present invention can be used for other electrical connection parts such as terminals, connectors, and switches.

Claims (12)

Copper-titanium at 100 at. % Titanium at 1 at. % Or more, 7.5 at. % Or less, and further copper-titanium-hydrogen at 100 at. % Hydrogen at 0.1 at. % X-ray diffraction integral of the {220} crystal plane on the alloy surface in a copper-titanium-hydrogen alloy having a composition that is not less than 2 times the titanium content (at% conversion) and the balance is copper and inevitable impurities When the intensity is I {220} and the X-ray diffraction integrated intensity of the {220} crystal plane of the pure copper standard powder is I ₀ {220}, the crystal orientation satisfies I {220} / I ₀ {220} ≦ 3.0 A copper-titanium-hydrogen alloy having an average twin width of a parent phase of 10 nm or less, a density of twin boundaries of 30 lines / μm or more, and a titanium-hydrogen compound. The copper-titanium-hydrogen alloy according to claim 1, wherein a copper-titanium compound or a titanium-hydrogen compound having a size of 10 nm or less is present at a twin interface.   100 at. %, And at. %, Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1.0% or less Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2.0% or less The copper-titanium-hydrogen alloy of Claim 1 or 2 containing 1 or more types.   The copper-titanium-hydrogen alloy according to any one of claims 1 to 3, which has a tensile strength of 950 MPa or more and a conductivity of 15% IACS or more.   The copper-titanium-hydrogen alloy according to any one of claims 1 to 4, wherein a ratio R / t of a minimum bending radius R to a sheet thickness in a 90 ° W bending test is 2.0 or less.   Copper-titanium at 100 at. % Titanium at 1 at. % Or more, 7.5 at. %, And after the solution treatment of the copper-titanium alloy having the composition of the remaining copper and unavoidable impurities, a pre-aging treatment for precipitating a copper-titanium compound is performed, and then cold rolling is performed, A method for producing a copper-titanium-hydrogen alloy, which is aged in a hydrogen atmosphere.   The manufacturing method of the copper-titanium-hydrogen alloy of Claim 6 whose rolling reduction of the said cold rolling is 30% or less.   The method for producing a copper-titanium-hydrogen alloy according to claim 6 or 7, wherein the preliminary aging treatment is performed in a range of 300 to 500 ° C.   The method for producing a copper-titanium-hydrogen alloy sheet according to claim 8, wherein the preliminary aging treatment is performed in a range of 5 to 240 minutes.   The method for producing a copper-titanium-hydrogen alloy sheet according to any one of claims 6 to 9, wherein the heat treatment temperature in the hydrogen atmosphere is in the range of 300 to 400 ° C.   The method for producing a copper-titanium-hydrogen alloy sheet according to any one of claims 6 to 10, wherein the hydrogen pressure in the aging treatment in the hydrogen atmosphere is less than 1 MPa.   Copper-titanium at 100 at. %, And at. %, Zr: 0.5% or less, Cr: 1.0% or less, Mg: 0.5% or less, Ni: 2.0% or less, Fe: 0.5% or less, Co: 1.0% or less Si: 1.0% or less, Sn: 1.0% or less, Mn: 1.0% or less, V: 1.0% or less, P: 0.1% or less, and Zn: 2.0% or less The method for producing a copper-titanium-hydrogen alloy sheet according to any one of claims 6 to 11, wherein a solution treatment of a copper-titanium alloy containing at least one kind is performed.