JP5084106B2 - Copper titanium alloy sheet and method for producing the same - Google Patents

Description

  The present invention relates to a copper titanium alloy sheet material that achieves both strength and electrical conductivity and a method for manufacturing the same.

  Recently, copper-titanium alloy sheets having excellent strength and conductivity have been developed as conductive spring materials. Conventionally, a copper-titanium alloy plate material is subjected to a solution treatment to form a solid solution, and then rolled to impart strain, and then maintained at a constant temperature, for example, 450 ° C. for 3 to 10 hours, for example, for isothermal aging. It was manufactured by processing. At this time, the heating temperature and the holding time in the isothermal aging treatment have been determined so that the strength is maximized (see, for example, Non-Patent Documents 1 to 3).

Ikeno, et al. 2 “Effect of Ti concentration on aging of Cu—Ti alloy”, Journal of the Japan Institute of Metals (1974), Vol. 38, No. 5, p. 446-451 Saji and two others, “On annealing hardening and softening of Cu-Ti alloy rolled after aging”, Journal of the Japan Institute of Metals (1974), Vol. 38, No. 7, p. 591-599 S. Nagaryuna, and et. Al, "Effects of Cold Work on Precipitation Hardening of Cu-4.5 mass% Ti Alloy" Materials Transactions, JIM, Vol.36, No.8 (1995), p.1058-1066

  However, the conventional techniques described above have the following problems. In the aging treatment described above, there is an aging treatment time in which the strength of the copper-titanium alloy sheet becomes the maximum value, and the strength increases as the aging treatment time increases on the short time side, and the aging treatment on the long time side. The strength decreases as the processing time increases. On the other hand, the timing of the increase in the conductivity accompanying the aging treatment is later than the timing of the increase in the strength, and the conductivity reaches the maximum value after the strength reaches the maximum value and starts to decrease. That is, the aging treatment time at which the electrical conductivity reaches the maximum value is longer than the aging treatment time at which the strength reaches the maximum value. For this reason, no matter how the aging treatment conditions are selected, it is impossible to achieve both high strength and high conductivity. That is, if the aging treatment time is shortened in order to maximize the strength, the conductivity becomes insufficient. Further, if the aging treatment time is lengthened in order to maximize the conductivity, the strength is lowered.

  This invention is made | formed in view of this problem, Comprising: It aims at providing the copper titanium alloy board | plate material which can make high intensity | strength and high electrical conductivity compatible, and its manufacturing method.

Method for producing a copper titanium alloy sheet according to the present invention contains Ti, the residual portion is made of copper and unavoidable impurities, the content of T i is 2. Rolling so that the copper titanium alloy material of 9 to 3.5% by mass is heated to a temperature at which the precipitate is dissolved, and the processing rate is 10 to 50% with respect to the copper titanium alloy material. A first rolling step for performing heat treatment, an aging treatment step for performing heat treatment at a temperature of 500 to 600 ° C. for a time of 150 seconds to 30 minutes, and a second rolling for performing rolling so that the processing rate is 10 to 50%. A cooling aging step in which cooling is performed while performing an aging treatment from 450 ° C. to 300 ° C. over 10 to 25 hours, and a third rolling step in which rolling is performed so that the processing rate is 10 to 50%. It is characterized by having. Another method for producing a copper-titanium alloy material according to the present invention contains Ti, and further contains one or more metals selected from the group consisting of P, Si and Mg, and the balance is made of copper and inevitable impurities. Thus, the total content of Ti, P, Si and Mg is 2.9 to 3.5% by mass, the P content is 0.08 to 0.25% by mass, and the Si content is 0. A solution treatment step of heating a copper titanium alloy material having a Mg content of 0.08 to 0.4% by mass to a temperature at which the precipitate is dissolved, A first rolling step of rolling the titanium alloy material so that the processing rate is 10 to 50%; an aging treatment step of performing a heat treatment at a temperature of 500 to 600 ° C. and a time of 150 seconds to 30 minutes; A second rolling step for rolling so that the processing rate is 10 to 50%; A cooling aging step of cooling while performing an aging treatment from 10 ° C. to 300 ° C. over 10 to 25 hours, and a third rolling step of rolling so that the processing rate is 10 to 50%. It is characterized by.

  In the present invention, an aging treatment is performed at a higher temperature and a shorter time than in the past, and rolling is performed before and after this aging treatment, so that it is difficult to become over-aged and the electrical conductivity is improved while maintaining high strength. Aging treatment can be continued. As a result, both high strength and high electrical conductivity can be achieved.

  In addition, the cooling aging step includes a step of holding the copper titanium alloy material at a first temperature in a range of 300 to 450 ° C. for a certain time, and a range of 300 to 450 ° C. that is lower than the first temperature. And maintaining the second temperature for a certain period of time. Alternatively, the cooling aging step may be a step of continuously decreasing the temperature of the copper titanium alloy material from 450 ° C. to 300 ° C.

Furthermore, when the temperature of the aging treatment step is 500 ° C., the time of the aging treatment step is preferably 20 to 30 minutes. Alternatively, when the temperature of the aging treatment step is 600 ° C., the time of the aging treatment step is preferably 150 to 200 seconds.
The copper-titanium alloy sheet according to the present invention is a copper-titanium alloy sheet produced by the above-described production method, and has a tensile strength of 950 MPa or more and an electrical conductivity of 18% IACS or more.
Furthermore, another copper titanium alloy sheet according to the present invention is a copper titanium alloy sheet manufactured by the above manufacturing method, and has a tensile strength of 950 to 1050 MPa and an electrical conductivity of 18 to 22% IACS. Features.

  According to the present invention, a copper titanium alloy sheet material is subjected to an aging treatment at a higher temperature and a shorter time than before, and rolling is performed before and after the aging treatment, thereby achieving both high strength and high electrical conductivity. be able to.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, a first embodiment of the present invention will be described. This embodiment is an embodiment of a copper titanium alloy sheet. The copper-titanium alloy sheet according to the present embodiment contains, for example, 3.2% by mass of titanium (Ti) in the parent phase made of copper (Cu). In addition to Ti, containing one or more metals selected P, from the group consisting of Si and Mg. The total content of Ti, P, Si and Mg is 2.9 to 3.5% by mass, the P content is 0.25% by mass or less, and the Si content is 0.4% by mass or less. Yes, the Mg content is 1.0 mass% or less.

Then, X-ray diffraction is performed on the main surface of the plate material, that is, the rolling surface, the peak intensity indicating the (111) crystal plane is defined as I _(111), and the peak intensity indicating the (220) crystal plane is defined as I. _{When (220)} , the value of the peak intensity ratio (I ₍₂₂₀₎ / I ₍₁₁₁₎ ) is 4 or more, for example, 6.75. The copper titanium alloy sheet according to the present embodiment has a tensile strength of, for example, 950 to 1050 MPa and a conductivity of, for example, 18 to 22% IACS. Note that “% IACS”, which is a unit of conductivity, is a relative value when the conductivity of pure copper is 100.

According to the present embodiment, in the copper titanium alloy sheet material in which the total content of Ti, P, Si and Mg is 2.9 to 3.5% by mass, the value of the ratio (I ₍₂₂₀₎ / I ₍₁₁₁₎ ) By setting the value to 4 or more, both strength and conductivity can be improved.

  Hereinafter, the reason for the numerical limitation in each constituent requirement of the present invention will be described.

Total content of Ti, P, Si and Mg: 2.9 to 3.5% by mass
If the total content of Ti, P, Si and Mg is less than 2.9% by mass, the conductivity of the copper titanium alloy sheet will be high, but the strength will be insufficient. On the other hand, when the content exceeds 3.5% by mass, the strength of the copper-titanium alloy sheet is increased, but the electrical conductivity is insufficient. Therefore, the total content of Ti, P, Si, and Mg is 2.9 to 3.5% by mass in order to achieve both the strength and conductivity of the copper titanium alloy sheet.

P content: 0.25 mass% or less If the P content exceeds 0.25 mass%, the electrical conductivity of the copper titanium alloy sheet increases, but the tensile strength decreases. Accordingly, the P content is 0.25% by mass or less.

Si content: 0.4 mass% or less When the Si content exceeds 0.4 mass%, the electrical conductivity of the copper titanium alloy sheet increases, but the tensile strength decreases. Accordingly, the Si content is set to 0.4 mass% or less.

Mg content: 1.0% by mass or less When the Mg content exceeds 1.0% by mass, cracking easily occurs during hot rolling performed before the solution treatment step. For this reason, a copper titanium alloy board cannot be manufactured stably. Therefore, the Mg content is 1.0% by mass or less.

Ratio (I ₍₂₂₀₎ / I ₍₁₁₁₎ ) value: 4 or more As will be described in detail in the second embodiment described later, the copper titanium alloy sheet according to this embodiment is a copper titanium after solution treatment. The alloy material is subjected to rolling and short-term aging treatment to precipitate a large amount of fine precipitated particles, and then subjected to multistage aging treatment to further precipitate particles so that the electrical conductivity exceeds the target value, and then further rolling. In this way, the processing strain is introduced to improve the strength even if the electrical conductivity is somewhat reduced, and the manufacturing is performed. Thereby, it is possible to obtain a copper-titanium alloy plate material in which the precipitated particles that are less likely to be over-aged and that contribute to the improvement of the conductivity are sufficiently precipitated. Thus, since the copper titanium alloy sheet according to the present embodiment is subjected to many processes in the manufacturing process, the peak intensity I ₍₂₂₀₎ indicating the (220) crystal plane is increased on the rolled surface. For this reason, the value of the ratio of peak intensity (I ₍₂₂₀₎ / I ₍₁₁₁₎ ) is 4 or more.

  More specifically, it is the size and precipitation density of the precipitated particles that affect the tensile strength and conductivity of the copper titanium alloy sheet. Then, it is the temperature and strain at which the precipitated particles precipitate that influence the size and the density of the precipitated particles. The crystal structure of copper is fcc, and when rolling is performed, the crystal rotates and shows a change in orientation relative to the processing axis. In other words, the crystal plane of the rolled surface basically approaches the (110) plane with the rolling process. The (110) plane is a plane parallel to the (220) plane. As the rolling processing rate increases, the crystal plane other than the (220) plane on the rolled plane also approaches the (220) plane.

The rolling process in the conventional method for producing a copper-titanium alloy sheet and the rolling process in the method for producing a copper-titanium alloy sheet according to the present invention are equivalent to an overall processing rate of about 50%. Since the rolling process is performed later, a large strain can be introduced into the alloy material. For example, the rolling with a processing rate of 20% after the solution forming step is performed as in the embodiment of the present invention, rather than performing the rolling with a processing rate of 50% after the solution forming step and performing the aging treatment thereafter. If the aging treatment process is performed at a temperature of 600 ° C. and then rolling with a processing rate of 40% is performed, a large strain can be introduced into the alloy sheet. The degree of introduction of this strain can be detected by the value of the peak ratio (I ₍₂₂₀₎ / I ₍₁₁₁₎ ). That is, as the strain introduced into the copper-titanium alloy sheet increases, the (220) plane on the rolled surface increases and the value of the peak ratio (I ₍₂₂₀₎ / I ₍₁₁₁₎ ) increases. As a result, the precipitated particles are precipitated with a suitable size and density, and good tensile strength and electrical conductivity can be realized. If the value of the ratio is 4 or more, the strain introduced into the copper titanium alloy sheet is sufficiently large, and good tensile strength and electrical conductivity can be obtained.

  Next, a second embodiment of the present invention will be described. This embodiment is an embodiment of a method for producing a copper titanium alloy sheet according to the first embodiment described above. FIG. 1 is a graph showing a manufacturing process of a copper-titanium alloy sheet according to the present embodiment, with time on the horizontal axis and the temperature of the copper-titanium alloy sheet on the vertical axis. In FIG. 1, the length of the horizontal axis is not necessarily proportional to the actual time length. 2 (a) and 2 (b) are TEM (Transmission Electron Microscope) photographs showing the copper titanium alloy plate material in the process of production, (a) shows the precipitated particles precipitated by aging treatment, (B) shows the precipitated particles after the final rolling. Note that the length of the scale in FIGS. 2A and 2B is 100 nm.

First, titanium (Ti) is contained, for example, 3.2% by mass, and in addition to Ti, one or more metals selected from the group consisting of P, Si and Mg are contained, and Ti, P, The total content of Si and Mg is 2.9 to 3.5% by mass, the content of P is 0.25% by mass or less, the content of Si is 0.4% by mass or less, A copper titanium alloy material having a content of 1.0% by mass or less is prepared. Then, as shown in the solution treatment step S1 in FIG. 1, the copper titanium alloy material is held at a temperature at which the precipitate is solid-solved, for example, 900 ° C., for example, for 3 minutes. Next, as shown in the rolling step S2 in FIG. 1, the copper titanium alloy material is subjected to a rolling process at room temperature so that the processing rate is 10 to 50%. In addition, a processing rate means the reduction rate (area reduction rate) of the area of the cross section orthogonal to the rolling direction in a copper titanium alloy material. Next, as shown in the aging treatment step S3, the rolled copper titanium alloy material is subjected to heat treatment at a temperature of 500 to 600 ° C. for a time of 150 seconds to 30 minutes to be aged. Next, as shown in rolling step S4, the copper titanium alloy material after the aging treatment is subjected to a rolling treatment at room temperature so that the processing rate becomes 10 to 50%.

  Next, as shown in the cooling aging step S5 of FIG. 1, a multi-stage aging process is performed. For example, after holding at a temperature of 450 ° C. for 3 hours, holding at a temperature of 400 ° C. for 3 hours, holding at a temperature of 350 ° C. for 3 hours, and then holding at a temperature of 300 ° C. for 10 hours. That is, in the cooling aging step S5, cooling is performed while performing an aging treatment from 450 ° C. to 300 ° C. over 19 hours. Thereafter, the copper titanium alloy material is cooled to room temperature. Next, as shown in rolling step S6 of FIG. 1, a rolling process is performed at room temperature so that the processing rate becomes 10 to 50%. As a result, the copper titanium alloy sheet according to the first embodiment is manufactured.

In the present embodiment, the aging treatment step S3 shown in FIG. 1 is performed at a temperature of 500 to 600 ° C. This temperature is a temperature that becomes over-aged if it is an aging treatment in a conventional method for producing a copper-titanium alloy sheet, and is a temperature at which the precipitated particles become coarse and the strength of the copper-titanium alloy material decreases. However, even if the present inventors perform an aging treatment at such a high temperature, by providing the rolling steps S2 and S4 before and after the aging treatment step S3, strain is imparted to the copper titanium alloy material to cause nucleation. By increasing the opportunity and shortening the aging treatment time as compared with the prior art, as shown in FIG. 2 (a ), a technology for generating extremely small precipitated particles at a high density at the time after the rolling step S4. developed. In FIG. 2A, precipitated particles having a diameter of 10 to 20 nm are observed as black spots (high density).

  Moreover, when the cooling aging treatment S5 shown in FIG. 1 is applied to the copper titanium alloy material in which fine precipitate particles are generated at a high density, titanium atoms in the copper titanium alloy material diffuse in a short range, Fine precipitate particles can be further precipitated. As a result, it is possible to prevent a small number of precipitated particles from becoming coarse and to disperse the nanometer-sized precipitated particles in the copper titanium alloy sheet at high density. Thereby, as shown in FIG.2 (b), the precipitation particle | grains whose particle size is about 10 thru | or 20 nm are obtained. In FIG. 2B, the precipitated particles are observed as black spots. Thus, since the particle size of the precipitated particles is kept small, the precipitated particles contribute to the strength of the copper titanium alloy sheet, and the strength of the copper titanium alloy sheet can be increased. At this time, since titanium precipitates from the copper matrix to near the solid solution limit, the conductivity of the copper titanium alloy sheet can be increased. Further, by providing the rolling step S6 after the cooling aging treatment S5, it is possible to improve the strength of the copper titanium alloy sheet and to prevent the electrical conductivity from decreasing.

  As described above, according to the present embodiment, by setting the aging treatment at a higher temperature and shorter time than conventional, it is possible to suppress the growth of the precipitated particles and to obtain a good conductivity while maintaining a high strength.

  Hereinafter, the reason for the numerical limitation in each constituent requirement of the present invention will be described.

Aging temperature: 500 to 600 ° C
When the aging treatment temperature exceeds 600 ° C., the precipitated particles become coarse and become over-aged. As a result, the strength of the copper titanium alloy sheet is reduced. On the other hand, when the aging treatment temperature is less than 500 ° C., the time required for the aging treatment becomes long, and the design of the production line becomes difficult. Moreover, production efficiency is lowered. Therefore, the aging treatment temperature is set to 500 to 600 ° C.

Aging treatment time: 150 seconds to 30 minutes When the aging treatment temperature is 500 ° C., the tensile strength of the produced copper titanium alloy sheet is good. The aging treatment time is 20 to 30 minutes, and the conductivity is good. The aging treatment time is 20 minutes or more. Therefore, when the aging treatment temperature is 500 ° C., the aging treatment time that can achieve both good tensile strength and electrical conductivity is 20 to 30 minutes. Further, when the aging treatment temperature is 600 ° C., the aging treatment time at which the tensile strength of the produced copper titanium alloy sheet is good is 200 seconds or less, and the aging treatment time at which the conductivity is good is 150 seconds or more. is there. Therefore, when the aging treatment temperature is 600 ° C., the aging treatment time capable of achieving both good tensile strength and electrical conductivity is 150 to 200 seconds. For this reason, when the aging treatment temperature is 500 to 600 ° C., the aging treatment time capable of achieving both good tensile strength and electrical conductivity is 150 seconds to 30 minutes.

Cooling aging temperature: 300 ° C to 450 ° C
When the cooling aging process is started from a temperature higher than 450 ° C., the copper titanium alloy material is over-aged and the strength of the copper titanium alloy sheet is lowered. On the other hand, even if the cooling aging step is performed up to a temperature of less than 300 ° C., the precipitation of particles cannot be expected at a temperature of less than 300 ° C., which is meaningless. For this reason, the temperature of the copper titanium alloy material in a cooling aging process shall be 300 to 450 degreeC.

Cooling aging time: 10 to 25 hours When the cooling aging time is less than 10 hours, precipitation of the precipitated particles becomes insufficient. On the other hand, if the cooling aging time is longer than 25 hours, the following problems occur. That is, if the time in the temperature range of 450 to 400 ° C. is lengthened, it becomes over-aged and the strength of the copper titanium alloy sheet is lowered. Further, when only the time in the temperature range of 350 to 300 ° C. is increased without increasing the time in the temperature range of 450 to 350 ° C., energy is wasted although there is little influence on the strength of the copper titanium alloy sheet. Therefore, the cooling aging time is 10 to 25 hours.

Processing rate in each rolling process: 10 to 50%
If the processing rate is less than 10%, the strain imparted to the copper titanium alloy material is reduced, and the strength and conductivity of the copper titanium alloy sheet are lowered. On the other hand, when the processing rate exceeds 50%, the electrical conductivity of the copper titanium alloy sheet increases, but the strength decreases. Therefore, the processing rate in each rolling process is 10 to 50%.

  In the present embodiment, an example in which the multi-stage aging treatment is performed in the cooling aging step S5 is shown, but the present invention is not limited to this, and the temperature of the copper titanium alloy material is changed from 450 ° C. to 300 ° C. for 10 to 25 hours. For example, a continuous cooling process may be performed.

  Hereinafter, the effect of the embodiment of the present invention will be specifically described in comparison with a comparative example that deviates from the scope of the claims. In Example 1, the influence of the aging treatment time on the conductivity and tensile strength of the copper titanium alloy sheet will be described. FIG. 3 (a) is a graph showing the effect of aging treatment time on tensile strength, with the horizontal axis representing aging treatment time and the vertical axis representing tensile strength, and FIG. 3 (b) representing aging treatment time on the horizontal axis. FIG. 5 is a graph showing the effect of aging treatment time on conductivity, taking conductivity on the vertical axis.

  First, a copper titanium alloy material containing 3.2% by mass of titanium (Ti) in a parent phase made of copper (Cu), the balance being made of copper (Cu) and inevitable impurities, and a plate thickness of 0.4 mm. Prepared. The alloy material was subjected to a solution treatment at a temperature of 900 ° C. and for a time of 3 minutes. Next, the alloy material after the solution treatment was subjected to rolling so that the processing rate (area reduction rate) was 20%. Next, an aging treatment at a temperature of 600 ° C. was performed. At this time, the aging treatment time was varied within a range of 50 to 250 seconds. Next, rolling was performed so that the processing rate was 40%. Next, multistage aging treatment was performed on the alloy material after the rolling process. The multi-stage aging treatment was carried out by holding at a temperature of 450 ° C. for 3 hours, holding at a temperature of 400 ° C. for 3 hours, holding at a temperature of 350 ° C. for 3 hours, and holding at a temperature of 300 ° C. for 10 hours. Thereafter, rolling was performed so that the processing rate was 30%. This produced the copper titanium alloy board | plate material.

  And the tensile strength and electrical conductivity of this copper titanium alloy board | plate material were measured. The measurement results are shown in FIGS. 3 (a) and 3 (b). As shown in FIG. 3 (a), when the aging treatment time is 150 seconds or longer, the tensile strength tends to decrease as the aging treatment time increases, but the aging treatment time is 50 to 200 seconds. In the range, the tensile strength of the copper titanium alloy sheet was as good as 980 MPa or more. On the other hand, as shown in FIG. 3 (b), when the aging treatment time is 170 seconds or less, there is a tendency that the conductivity decreases as the aging treatment time decreases, and the aging treatment time is less than 150 seconds. And the conductivity was less than 20% IACS.

In the second embodiment, as in the first embodiment, the influence of the aging treatment time on the conductivity and tensile strength of the copper titanium alloy sheet will be described. However, in the second embodiment, unlike the first embodiment, the aging treatment temperature was set to 500 ° C. The aging treatment time was 10 to 30 minutes. FIG. 4 is a graph showing the effect of aging treatment time on tensile strength and conductivity, with the aging treatment time on the horizontal axis and the tensile strength and conductivity on the vertical axis. As shown in FIG. 4, when the aging treatment time was in the range of 10 to 30 minutes, the tensile strength and the conductivity tended to increase as the aging treatment time increased, but in this aging treatment time range, it was good. High tensile strength and conductivity were obtained.

  In the present Example 3, the manufacturing method of the present invention as an example was compared with the conventional manufacturing method as a comparative example. First, a copper titanium alloy material containing 3.2% by mass of titanium in a parent phase made of copper and having a plate thickness of 0.4 mm was prepared. The alloy material was subjected to a solution treatment at a temperature of 900 ° C. and for a time of 3 minutes. Thereafter, as shown in Table 1, For the alloy materials 1 to 4, after rolling with a processing rate of 20%, an aging treatment is performed at a temperature of 500 to 600 ° C. for a short time (150 seconds to 12.5 minutes), and the processing rate is 40 % Rolling, multi-stage aging treatment, and rolling with a processing rate of 30%. On the other hand, no. The alloy materials 5 to 7 were subjected to aging treatment at a temperature of 420 ° C. or 450 ° C. for a long time (3 hours) after rolling with a processing rate of 54%, 50% or 24%, respectively. However, no. Rolling with a processing rate of 40%, multi-stage aging treatment, and rolling with a processing rate of 30% performed on the alloy materials 1 to 4 were not performed. Thereafter, the tensile strength and electrical conductivity of these alloy sheets were measured. The measurement results are shown in Table 1.

  No. shown in Table 1. Examples 1 to 4 are examples of the present invention. Example No. In Nos. 1 to 4, since the manufacturing conditions satisfied the scope of the present invention, both the tensile strength and the electrical conductivity were good. On the other hand, no. Reference numerals 5 to 7 are comparative examples. Comparative Example No. About 5 thru | or 7, when trying to match | combine the tensile strength to the same level as an Example, electrical conductivity is Example No .. It was lower than 1 to 4.

  No. 1 shown in Table 1 1 and no. The alloy plate material No. 5 was subjected to X-ray diffraction. FIG. 5 is a perspective view showing the surface of the alloy plate subjected to X-ray diffraction. As shown in FIG. 5, the copper titanium alloy sheet 11 is rolled along the rolling direction 12. X-ray diffraction was performed on a plane 13 which is the main surface of the copper-titanium alloy sheet 11 and is a rolling surface, and a parallel section 14 which intersects the plane 13 and is parallel to the rolling direction 12. The X-ray diffraction method was the θ-2θ method. 6A to 6D are graphs showing X-ray diffraction profiles with 2θ on the horizontal axis and peak intensity on the vertical axis, and FIG. 1 shows the profile of the plane of FIG. 1 shows a profile of a parallel section of No. 1 and (c) shows a comparative example No. 1 5 shows the profile of the plane of FIG. 5 shows a profile of 5 parallel sections.

Example No. shown in Table 1 1 and Comparative Example No. The total processing rate with 5 is substantially the same. However, as shown in FIGS. 6A and 6C, the ratio (I 1 _{(2 )} between the peak intensity I ₍₂₂₀₎ indicating the ₍₂₂₀ ) crystal plane and the peak intensity I ₍₁₁₁₎ indicating the (111) crystal plane. ₂₂₀₎ / I ₍₁₁₁₎ ) is the value of Example No. 1 was 6.75, and Comparative Example No. 1 5 was 3.60. That is, Example No. No. 1 is comparative example No.1. The relative intensity of the (220) peak was higher than 5.

In addition, as shown in FIGS. In No. 1, a peak 21 that was considered to be an influence of a copper titanium alloy ( Cu ₄ Ti alloy ) was observed in the vicinity of the (111) peak of the parallel section. On the other hand, Comparative Example No. For 5, no such peak was observed. For this reason, Example No. 1 is Comparative Example No. 1. It is considered that the crystal isotropic is higher with respect to the parallel section than 5.

  In Example 4, an experiment for extending the aging treatment time was performed on a conventional method for producing a copper titanium alloy sheet. In this case, the aging temperature was 350 to 450 ° C., which is a conventional aging temperature, and no rolling process was performed. And the tensile strength and electrical conductivity were measured about the board | plate material after an aging treatment. The measurement results are shown in FIGS. 7 (a) and (b). FIG. 7 (a) is a graph showing the effect of aging time on tensile strength in a conventional manufacturing method, with the aging time on the horizontal axis and the tensile strength on the vertical axis. (B) It is a graph which shows the influence which an aging time has on an electrical conductivity in a conventional manufacturing method, taking aging time on an axis | shaft and taking an electrical conductivity on a vertical axis | shaft.

  As shown in FIG. 7A, when the aging treatment temperature is 400 ° C. and 450 ° C., the tensile strength takes the maximum value when the aging treatment time is about 3 hours, and the aging treatment time is 3 When the time was exceeded, the tensile strength decreased as the aging treatment time increased. On the other hand, when the aging treatment temperature was 350 ° C., the tensile strength was low regardless of the aging treatment time. In contrast, conductivity continued to increase with increasing aging treatment time. For this reason, it can be seen that the conventional method cannot achieve both high strength and high conductivity regardless of the aging treatment time.

  Although not shown in the figure, when the rolling process was performed before the aging treatment, the tensile strength was increased as a whole, but the aging treatment time at which the tensile strength began to decrease was shortened. On the other hand, the electrical conductivity showed the same tendency as the case where no rolling process was performed. For this reason, when the aging treatment time was shortened in order to achieve high tensile strength, the conductivity was further lowered.

In Example 5, the influence of the composition of the copper titanium alloy sheet on the tensile strength and conductivity was investigated. First, an alloy material containing Ti in a matrix phase made of copper and containing any metal element of P, Si and Mg was melted. Table 2 shows the composition of this alloy material. And this alloy material was hot-rolled to produce a copper titanium alloy material having a plate thickness of 0.4 mm. Next, the alloy material was subjected to a solution treatment at a temperature of 900 ° C. and a time of 3 minutes. Next, this alloy material was cooled with water to room temperature, and then subjected to rolling with a processing rate of 20%. Next, subjected to time aging treatment at a temperature of 600 ° C., after cooling to room temperature, the working ratio is subjected to 40% rolling, subjected to cooling aging treatment. In this cooling aging treatment, the copper titanium alloy material is held at a temperature of 450 ° C. for 2 hours, then held at a temperature of 400 ° C. for 2 hours, held at a temperature of 350 ° C. for 2 hours, and held at a temperature of 300 ° C. for 10 hours. Multistage aging treatment. Then, after cooling the alloy material to water and cooling to room temperature, a rolling process with a processing rate of 20% was performed to manufacture a copper titanium alloy sheet. Thereafter, the tensile strength and electrical conductivity of these alloy sheets were measured. The measurement results are shown in Table 2. In addition, "-" shown in Table 2 indicates that the corresponding component is not contained. The balance other than the components shown in Table 2 is copper and inevitable impurities.

  No. shown in Table 2 11, 12, 14, 15, 17 to 20 are embodiments of the present invention. Example No. Nos. 11, 12, 14, 15, 17 to 20 had good tensile strength and electrical conductivity because the composition of the alloy material satisfied the scope of the present invention. In contrast, No. 2 shown in Table 2. 13, 16 and 21 are comparative examples. Comparative Example No. No. 13 had a tensile strength lower than that of the example because the Si content exceeded 0.4 mass%. Comparative Example No. No. 16 had a lower tensile strength than the examples because the P content exceeded 0.25 mass%. Comparative Example No. In No. 21, since the Mg content exceeded 1.0 mass%, it was cracked in hot rolling before the solution treatment step, and a copper titanium alloy sheet could not be produced. For this reason, the tensile strength and electrical conductivity of the alloy sheet are not measured.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used for a copper titanium alloy plate material used for a conductive spring material or the like and a manufacturing method thereof.

It is a graph which shows the manufacturing process of the copper titanium board | plate material which concerns on the 2nd Embodiment of this invention, taking time on a horizontal axis and taking the temperature of a copper titanium alloy material on a vertical axis | shaft. (A) And (b) is a drawing-substituting photograph showing a copper titanium alloy material in the course of production, (a) shows precipitation nuclei precipitated by aging treatment, and (b) shows precipitated particles after final rolling ( (TEM photograph: magnification on paper of 200000 times). (A) is a graph showing the effect of aging treatment time on tensile strength by taking the aging treatment time on the horizontal axis and the tensile strength on the vertical axis, and (b) shows the aging treatment time on the horizontal axis. It is a graph which shows the influence which electrical conductivity is taken on a vertical axis | shaft and an aging treatment time has on electrical conductivity. It is a graph which shows the influence which an aging treatment time has on the tensile strength and electrical conductivity, taking aging treatment time on a horizontal axis | shaft and taking a tensile strength and electrical conductivity on a vertical axis | shaft. It is a perspective view which shows the surface which performed the X-ray diffraction in the alloy board | plate material. (A) to (d) are graphs showing X-ray diffraction profiles with 2θ on the horizontal axis and peak intensity on the vertical axis, and (a) is an example No. shown in Table 1. 1 shows the profile of the plane of FIG. 1 shows a profile of a parallel section of No. 1 and (c) shows a comparative example No. 1; 5 shows the profile of the plane of FIG. 5 shows a profile of 5 parallel sections. (A) is a graph showing the effect of aging time on tensile strength in a conventional manufacturing method, with the aging time on the horizontal axis and the tensile strength on the vertical axis, and (b) is the horizontal axis. It is a graph which shows the influence which aging time has on aging in a conventional manufacturing method, taking aging time and taking a conductivity on a vertical axis | shaft.

Explanation of symbols

  11; copper titanium alloy sheet 12; rolling direction 13; plane 14; parallel cross section 21: peak S1; solution treatment step S2, S4, S6; rolling step S3; aging treatment step S5; cooling aging step

Claims (8)

A solution treatment step for heating a copper titanium alloy material containing Ti, the balance of copper and inevitable impurities, and containing Ti of 2.9 to 3.5% by mass to a temperature at which the precipitate is dissolved. And a first rolling step for rolling the copper-titanium alloy material to a processing rate of 10 to 50%, and an aging treatment for performing a heat treatment at a temperature of 500 to 600 ° C. and a time of 150 seconds to 30 minutes. A treatment step, a second rolling step for rolling so that the processing rate becomes 10 to 50%, and a cooling aging step for cooling while performing an aging treatment from 450 ° C. to 300 ° C. over 10 to 25 hours And a third rolling step in which rolling is performed so that the processing rate is 10 to 50%. It contains Ti, and further contains one or more metals selected from the group consisting of P, Si and Mg, the balance is made of copper and unavoidable impurities, and the total content of Ti, P, Si and Mg 2.9 to 3.5% by mass, P content is 0.08 to 0.25% by mass, Si content is 0.08 to 0.4% by mass, Mg content Is a solution treatment step of heating a copper titanium alloy material having a content of 0.08 to 1.0 mass% to a temperature at which the precipitate is dissolved, and the processing rate is 10 to 50% with respect to the copper titanium alloy material. The first rolling step for rolling, the aging treatment step for applying a heat treatment at a temperature of 500 to 600 ° C. for a time of 150 seconds to 30 minutes, and the first rolling step for applying a rolling rate of 10 to 50%. 2 rolling process and 450 to 300 ° C for 10 to 25 hours Method for producing a copper titanium alloy sheet, characterized in that it comprises only a cooling aging step of cooling while applying an aging treatment, a third rolling step of processing rate is to perform rolling such that 10 to 50%, a. The cooling aging step includes a step of holding the copper titanium alloy material at a first temperature in a range of 300 to 450 ° C. for a certain time, and a second in a range of 300 to 450 ° C. that is lower than the first temperature. And maintaining the temperature at a certain temperature for a certain period of time. The method for producing a copper-titanium alloy sheet according to claim 1 or 2 . The method for producing a copper titanium alloy sheet according to claim 1 or 2 , wherein the cooling aging step is a step of continuously reducing the temperature of the copper titanium alloy material from 450 ° C to 300 ° C. Wherein the temperature of the aging treatment step was 500 ° C., a manufacturing method of a copper titanium alloy sheet according to any one of claims 1 to 4 time of the aging treatment step, characterized in that the inter 20-30 minutes. 5. The method for producing a copper-titanium alloy sheet according to claim 1, wherein the temperature of the aging treatment step is 600 ° C., and the time of the aging treatment step is 150 to 200 seconds. A copper titanium alloy sheet produced by the method for producing a copper titanium alloy sheet according to any one of claims 1 to 6, wherein the tensile strength is 950 MPa or more and the conductivity is 18% IACS or more. A copper titanium alloy sheet characterized by A copper titanium alloy sheet produced by the method for producing a copper titanium alloy sheet according to any one of claims 1 to 6, wherein the tensile strength is 950 to 1050 MPa, and the conductivity is 18 to 22% IACS. A copper-titanium alloy sheet characterized by being.

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