JP5717236B2 - Particle accelerator - Google Patents

Description

The present invention, for example, those related to the particle acceleration device which is utilized as a laboratory equipment and medical equipment.

In the particle accelerator described above, a high-frequency high electric field is applied to a particle accelerator tube formed in a cylinder shape, particles (for example, electrons) passing through the particle accelerator tube are accelerated, and the accelerated particles are converted into, for example, a Si single crystal or the like. Irradiation generates electromagnetic waves (for example, X-rays), and diagnosis and treatment are performed using the electromagnetic waves.
In particular, the spatial interference X-ray obtained by accelerating the electron beam to about 100 MeV and colliding with a silicon single crystal or a diamond single crystal has the same X-ray phase with monochromatic light. A clear image of the internal structure can be taken, which is useful for medical diagnosis. In addition, since spatial interference X-rays can be focused, an energy peak can be positioned inside the object to be irradiated, and thus can be used for cancer treatment or the like.

  Here, in the above-described particle accelerator, a high-frequency high electric field is applied to the particle accelerator tube, so that a high-frequency current flows. When the particle accelerator is made of a material having high electrical resistance, the temperature due to Joule heat An increase will occur.

Conventionally, for example, as shown in Patent Documents 1 and 2, a particle accelerating tube made of a superconducting material has been provided. However, when a particle accelerator tube made of a superconducting material is used, there is a problem that the equipment configuration of the particle accelerator becomes large because it is necessary to cool to near zero, for example, 2K.
In addition, when a particle accelerator tube made of a superconducting material is used, power loss occurs when high-frequency power such as 5 GHz is applied. Therefore, the high-frequency power to be added must be 3 GHz or less. was there. Further, as described above, for example, in order to generate a spatial interference X-ray, in order to accelerate the electron beam to about 100 MeV, it is necessary to lengthen the particle accelerating tube, and the equipment configuration of the particle accelerator is also increased. There was a problem such as.

Therefore, for example, as shown in Patent Documents 3 and 4, a particle accelerating tube made of copper, which is a normal conductive material, is provided.
Here, the residual resistance ratio (RRR) is used as an index for evaluating the electrical resistance in a low temperature state. The residual resistance ratio (RRR) is a electrical resistivity [rho ₃₀₀ at room temperature (300K), the electrical resistivity at liquid helium temperature (4.2 K) in the case of the [rho _4.2, defined by the following formula It is what is done.
RRR = ρ ₃₀₀ / ρ _4.2
The larger the residual resistance ratio (RRR), the lower the electric resistance in a cryogenic environment, and thus it is particularly suitable as a particle acceleration tube.

JP-A 64-007500 JP 03-208300 A JP 2004-156090 A JP 09-316568 A

By the way, in general pure copper (4NCu) having a purity of 99.99 mass% or more and less than 99.999 mass%, the residual resistance ratio (RRR) was 1000 or less.
When the residual resistance ratio (RRR) is 1000 or less in a pure copper-based material, for example, since the electrical resistance in a cryogenic environment of 20K or less is not sufficiently low, when a high frequency high electric field is applied to the particle accelerator tube, Joule heat is generated and the temperature of the particle accelerating tube rises, and the cryogenic state is not maintained. As a result, the electrical resistance of the particle accelerating tube is further increased, Joule heat is generated, and the temperature of the particle accelerating tube is further increased, so that the particles cannot be accelerated stably.
In particular, in a particle accelerator for cancer treatment, since a higher voltage is applied to the particle accelerator tube, a particle accelerator tube made of 4NCu having a residual resistance ratio (RRR) of 1000 or less could not be used.

Further, in the particle accelerating tube made of 4NCu, since the no-load gain coefficient Q is low, the high frequency power loss is large and the particles cannot be accelerated efficiently.
Furthermore, even if a particle decelerating tube that decelerates the particle beam with 4NCu is used, the loss of high-frequency power is still large, so the particle beam cannot be sufficiently decelerated, and the beam dump is absorbed by the particle dump. Secondary particles such as neutrons are generated. Therefore, equipment for shielding the secondary particles is required, and there is a problem that the equipment configuration of the particle accelerator becomes large.

In addition, it is conceivable to use high-purity copper (6NCu) having a purity of 99.9999% by mass or more and less than 99.99999% by mass, but 6NCu having an impurity content of 1 ppm or less simply has a residual resistance ratio (RRR) of about 2500. That was not enough.
Here, if the purity is 99.99999 mass% or more and less than 99.999999 mass% ultra high purity copper (7NCu), the residual resistance ratio (RRR) exceeds 5000. It is very suitable as a constituent material. However, since 7NCu has a complicated manufacturing process, it is very expensive and difficult to use in general.

The present invention has been made in view of the above-described circumstances, and the residual resistance ratio (RRR) is relatively low even if the production cost is relatively inexpensive and easily available high purity copper (6NCu). An object of the present invention is to provide a particle accelerator using a copper material for a particle accelerator that is large and can be used stably even when a high frequency high electric field is applied in a cryogenic environment.

  In order to solve this problem, the present inventors have conducted intensive research. As a result, even for high-purity copper (6NCu), the residual resistance ratio (RRR) is controlled by controlling the content of a specific element. The inventors have found that it is possible to increase the electrical resistance in a low temperature environment.

The present invention has been made based on such knowledge, and the particle accelerator according to the present invention includes a particle accelerator tube for accelerating a particle beam, an electromagnetic wave generator for generating an electromagnetic wave using the accelerated particle beam, and A particle decelerating tube that decelerates the particle beam that has passed through the electromagnetic wave generator, a beam dump that absorbs the particle beam that has passed through the particle decelerating tube, a cooler that cools the particle accelerating tube and the particle decelerating tube, The particle accelerator tube and the particle decelerating tube are diffusion bonded to a first cylindrical member, a second cylindrical member, a disk-shaped member, and a block member made of a copper material for a particle accelerator. In the particle accelerator copper material, the purity of Cu excluding gas components is 99.9999 mass% or more and less than 99.99999 mass%, and the Fe content is 0.04 pp. m or less, P content is 0.04 ppm or less, Al content is 0.05 ppm or less, As content is 0.03 ppm or less, Sn content is 0.04 ppm or less, and S content is 0.00. It is characterized in that it is 06 ppm or less, the content of impurities including Fe, P, Al, As, Sn and S is 0.37 ppm or less , and the residual resistance ratio is 3000 or more.

In the particle accelerator of the present invention configured as described above, the particle accelerating tube for accelerating the particle beam and the particle decelerating tube for decelerating the particle beam include a first cylindrical member made of a copper material for the particle accelerator, The two-cylindrical member, the disk-shaped member, and the block member are formed by diffusion bonding, and the copper material for the particle accelerator has a purity of Cu of 99.9999 mass% or more and 99.999999 mass% excluding gas components. Fe content is 0.04 ppm or less, P content is 0.04 ppm or less, Al content is 0.05 ppm or less, As content is 0.03 ppm or less, and Sn content is 0. 0.04 ppm or less, the content of S is 0.06 ppm or less, the content of impurities including Fe, P, Al, As, Sn, and S is 0.37 ppm or less, and the residual resistance ratio is 3000 As described above, for example, since the electric resistance is sufficiently low under an extremely low temperature environment of 20K or less, even when a high frequency high electric field is applied to the copper material for particle accelerator, generation of Joule heat is suppressed. It becomes possible to do. In addition, since the no-load gain coefficient Q is high and high-frequency power loss is suppressed, particles can be efficiently accelerated and decelerated, and the particle accelerator itself can be downsized.
In addition, since the particle beam is sufficiently decelerated in the particle decelerating tube, the generation of secondary particles such as neutrons is suppressed when the particle beam that has passed through the particle decelerating tube is absorbed by the beam dump. Thus, the shielding facility can be simplified. Furthermore, the particle accelerator copper material made of 6NCu constituting the particle accelerator tube and the particle reducer tube suppresses the release of gas from the inside, so that the surroundings of the particle accelerator tube and the particle reducer tube can be relatively easily vacuumed. It becomes possible.

Here, the copper material for the particle accelerator has an Fe content of less than 0.01 ppm, a P content of less than 0.01 ppm, an Al content of less than 0.01 ppm, and an As content of less than 0.01 ppm. It is preferable that the Sn content is less than 0.01 ppm, the S content is less than 0.05 ppm, and the residual resistance ratio is 5000 or more.
In this case, the Fe content is less than 0.01 ppm, the P content is less than 0.01 ppm, the Al content is less than 0.01 ppm, the As content is less than 0.01 ppm, and the Sn content is 0.00. By defining the content of less than 01 ppm and the content of S as less than 0.05 ppm, the residual resistance ratio can be set to 5000 or more. That is, even with 6NCu, a residual resistance ratio equivalent to 7NCu can be obtained.
Therefore, for example, since the electrical resistance is further reduced in an extremely low temperature environment of 20K or less, even when a high frequency high electric field is added to the copper material for particle accelerator, it is possible to reliably suppress the generation of Joule heat. Become. In addition, since the no-load gain coefficient Q is high and high-frequency power loss is suppressed, particles can be accelerated and decelerated more efficiently, and the particle accelerator itself can be downsized. Furthermore, the manufacturing cost can be greatly reduced as compared with 7NCu, which is difficult to manufacture.

Moreover, you may heat-process for 1 hour or more with 400 degreeC or more and less than melting | fusing point with respect to the 1st cylindrical member, 2nd cylindrical member, disk-shaped member, and block member which carried out diffusion bonding .
In this case, since the heat treatment is performed at 400 ° C. or higher and lower than the melting point, desirably 1000 ° C. or less with less deformation of the material for 1 hour or more, the strain accumulated in the copper material for particle accelerator by processing is released by the heat treatment step. And the residual resistance ratio (RRR) can be increased.

Here, a waveguide that connects the particle acceleration tube and the particle deceleration tube is provided, and the high-frequency power recovered by the particle deceleration tube is supplied to the particle acceleration tube. However, it is preferable to be comprised with the above-mentioned copper material for particle accelerators.
In this case, the waveguide connecting the particle accelerator tube and the particle decelerating tube is composed of a copper material for particle accelerator made of 6NCu having a residual resistance ratio of 3000 or more. Loss when supplying the recovered high frequency power to the particle accelerating tube can be suppressed, the recovered high frequency power can be reliably reused, and the amount of energy used can be greatly reduced.

Moreover, it is preferable to provide an adiabatic vacuum container that houses the particle acceleration tube, the particle deceleration tube, and the waveguide.
By storing the particle accelerator tube, the particle decelerating tube, and the waveguide in the same adiabatic vacuum vessel and cooling them to an extremely low temperature, the high frequency power loss can be reduced and the high frequency power can be reliably reused. At the same time, by integrating the heat insulating vacuum vessel, it is possible to reduce the size and efficiently cool.

Moreover, it is preferable that the length of the particle acceleration tube is the same as the length of the particle deceleration tube.
In this case, the high frequency power recovered by the particle deceleration tube can be efficiently supplied to the particle acceleration tube, and energy loss can be suppressed.

Furthermore, it is preferable that the particle accelerator tube and the particle deceleration tube are connected to the cooler via a connecting member, and the connecting member is made of the above-described copper material for a particle accelerator.
In this case, since the connection member that connects the cooler to the particle accelerator tube and the particle deceleration tube is made of a copper material for particle accelerator made of 6NCu having a residual resistance ratio of 3000 or more, the thermal conductivity Is excellent. Therefore, the particle accelerating tube and the particle decelerating tube can be efficiently cooled, and the configuration of the cooler can be simplified.

According to the present invention, even in the case of high-purity copper (6NCu), which is relatively inexpensive and easy to obtain, the residual resistance ratio (RRR) is relatively large, and a high-frequency high electric field can be generated in a cryogenic environment. the added even can be stably provide particle acceleration instrument that can be used.

It is a schematic explanatory drawing of the particle accelerator which is embodiment of this invention. It is explanatory drawing which shows the use condition of the particle accelerator pipe (particle deceleration tube) which consists of a copper tube for particle accelerators which is embodiment of this invention. It is a flowchart which shows the manufacturing method of the copper tube for particle accelerators which consists of a copper material for particle accelerators which is embodiment of this invention. It is explanatory drawing of the structural member joined in the diffusion joining process shown in FIG.

Below, the copper material for particle accelerators which is an embodiment of the present invention, the copper tube for particle accelerators, the manufacturing method of the copper tube for particle accelerators, and the particle accelerator are explained.
First, the particle accelerator 10 which is this embodiment is demonstrated using FIG.
The particle accelerator 10 includes an electron gun 11 that emits an electron beam 18, a particle accelerator tube 20 that accelerates the electron beam 18, and an X-ray generator that generates a spatial interference X-ray 19 using the accelerated electron beam 18. 12, a particle decelerating tube 30 that decelerates the electron beam 18 that has passed through the X-ray generator 12, a beam dump 13 that absorbs the electron beam 18 that has passed through the particle decelerating tube 30, a particle accelerator tube 20, and a particle decelerating tube 30, a high-frequency power source 15 that supplies high-frequency power toward the particle accelerating tube 20 and the particle decelerating tube 30, and a directional coupler 16 that connects the waveguide 14 and the high-frequency power source 15. And.

In the particle accelerator 10, high frequency power of about 5.7 GHz is applied to the particle accelerator tube 20, and the electron beam 18 emitted from the electron gun 11 is accelerated to, for example, 100 MeV by the particle accelerator tube 20. Will be. The accelerated electron beam 18 is introduced into the X-ray generator 12 and is collided with a single crystal of silicon or carbon. Then, the spatial interference X-ray 19 is generated from the X-ray generator 12. The electron beam 18 that has passed through the X-ray generator 12 is decelerated by the particle decelerating tube 30 and then collides with the beam dump 13 and is absorbed.
Here, the particle acceleration tube 20 and the particle deceleration tube 30 are supplied with high frequency from the high frequency power supply 15 through the directional coupler 16. High frequency power is supplied to the electron beam 18 by the particle accelerator tube 20, and high frequency power is recovered from the electron beam 18 by the particle decelerating tube 30. The high-frequency power recovered by the particle decelerating tube 30 is supplied to the particle accelerating tube 20 through the waveguide 14.

  The spatial interference X-rays 19 generated from the X-ray generator 12 are monochromatic light and have the same X-ray phase, so that it is possible to capture a clear image of the internal structure of soft tissue such as the internal organs. Therefore, it can be used for medical diagnosis. Further, since the spatial interference X-ray 19 can be focused, it is possible to position an energy peak inside the object, so that it can be used for cancer treatment or the like.

Here, the particle accelerating tube 20 and the particle decelerating tube 30 are composed of the same size (length, diameter) copper tube for particle accelerator, and incident with the high frequency power added to the particle accelerator copper tube. The electron beam 18 is accelerated or decelerated depending on the phase with the electron beam 18.
As shown in FIG. 2, the particle accelerating tube 20 and the particle decelerating tube 30 are connected to the coolers 25 and 35 via connecting members 21 and 31, and are used in a cryogenic environment such as 20K or less. It is said that.

And the particle accelerator tube 20 and the particle deceleration tube 30 are comprised with the copper material for particle accelerators which is this embodiment.
This particle acceleration tube copper material is high-purity copper (6NCu) in which the purity of Cu excluding gas components is 99.9999 mass% or more and less than 99.99999 mass%, and among the impurities, the content of Fe is Less than 0.1 ppm, P content less than 0.1 ppm, Al content less than 0.1 ppm, As content less than 0.1 ppm, Sn content less than 0.1 ppm, and S content It is specified to be less than 0.1 ppm.

  Thus, even if it is high purity copper (6NCu) in which the purity of Cu excluding gas components is 99.9999 mass% or more and less than 99.99999 mass%, specific elements (Fe, P, Al, By defining the content of As, Sn, S), the residual resistance ratio (RRR) can be set to 3000 or more.

  Here, in the present embodiment, among the aforementioned impurities, the Fe content is less than 0.01 ppm, the P content is less than 0.01 ppm, the Al content is less than 0.01 ppm, and the As content is 0. Less than 0.01 ppm, Sn content is less than 0.01 ppm, and S content is less than 0.05 ppm. Thereby, the residual resistance ratio (RRR) can be set to 5000 or more.

In the particle accelerator 10 shown in FIG. 1, the waveguide 14 that connects the particle accelerator tube 20 and the particle decelerating tube 30 is also made of the particle accelerator copper material according to the present embodiment.
Further, the connecting member 21 that connects the cooler 25 and the particle accelerator tube 20 and the connecting member 31 that connects the cooler 35 and the particle decelerating tube 30 are also made of the copper material for particle accelerator according to the present embodiment. Yes.
The particle accelerating tube 20, the particle decelerating tube 30, and the waveguide 14 are accommodated in the same heat insulating vacuum vessel 17.

Below, the manufacturing method of the copper tube for particle accelerators which comprises the particle acceleration tube 20 and the particle deceleration tube 30 is demonstrated with reference to the flowchart of FIG.
This method for producing a copper tube for a particle accelerator is an ingot for producing an ingot of high-purity copper (6NCu) in which the purity of Cu excluding gas components from a copper raw material is 99.9999% by mass or more and less than 99.99999% by mass. A manufacturing process S10, a processing process S20 for forming the ingot into a final shape product by machining, and a heat treatment process S30 for performing a heat treatment on the final shape product are provided.

(Ingot manufacturing process S10)
First, a pure copper (4NCu) cathode having a purity of 99.99 mass% or more and less than 99.999 mass% is prepared as a copper raw material. This 4NCu cathode is dissolved in an electrolytic solution and subjected to an electrolytic treatment (electrolytic process S11). By this electrolysis step S11, a cathode of high-purity copper (6NCu) having a purity of 99.9999 mass% or more and less than 99.99999 mass% is produced.
Next, this 6NCu cathode is melted to produce a molten copper, degassed, etc., and the degassed copper is poured into a mold to produce an ingot of a predetermined shape (dissolved) -Casting step S12).
Of these impurities, Fe content of less than 0.01 ppm, P content of less than 0.01 ppm, Al content of less than 0.01 ppm, and As content of these electrolytic step S11 and melting / casting step S12 Is less than 0.01 ppm, the Sn content is less than 0.01 ppm, and the S content is less than 0.05 ppm.

(Processing step S20)
The obtained ingot is subjected to plastic processing such as forging, rolling and extrusion (primary processing step S21).
Then, a structural member is manufactured by machining (secondary processing step S22). At this time, in this embodiment, as shown in FIG. 4, the first cylindrical member 41, the second cylindrical member 42, the disk-shaped member 43, and the block member 44 are manufactured as constituent members. It will be.
And these particle | grain components (the 1st cylindrical member 41, the 2nd cylindrical member 42, the disk-shaped member 43, the block member 44) comprise the particle | grain acceleration tube 20 and the particle | grain reduction tube 30 by diffusion-bonding. A final shape product having the shape of a copper tube for a particle accelerator is produced (diffusion bonding step S23).

(Heat treatment step S30)
Then, heat treatment is performed on the final shape product produced. Here, as the heat treatment conditions, the temperature is set to 400 ° C. or higher and lower than the melting point, desirably 1000 ° C. or lower and the time is set to 1 hour or longer with little deformation of the material. The heat treatment step S30 is configured to release the distortion accumulated in the final shape product during the processing step S20.

(Finishing process S40)
Finally, if necessary, pickling or the like is performed to remove the oxide film or the like formed on the surface of the final shape product by the heat treatment step S30.
As described above, the particle accelerator copper pipe (the particle accelerator pipe 20 and the particle reducer pipe 30) made of the copper material for particle accelerator according to the present embodiment is produced.

  According to the copper material for particle accelerator and the copper tube for particle accelerator (particle acceleration tube 20 and particle deceleration tube 30) which are the present embodiment configured as described above, the purity of Cu excluding gas components is 99.9999. The Fe content is less than 0.1 ppm, the P content is less than 0.1 ppm, the Al content is less than 0.1 ppm, and the As content is 0.1 ppm. Less than, Sn content less than 0.1 ppm and S content less than 0.1 ppm, Furthermore, in this embodiment, Fe content is less than 0.01 ppm, P content is less than 0.01 ppm, Al The content is less than 0.01 ppm, the As content is less than 0.01 ppm, the Sn content is less than 0.01 ppm, and the S content is less than 0.05 ppm, and the residual resistance ratio is 5000 or more. Is There.

Accordingly, since the electric resistance is sufficiently low in an extremely low temperature environment of 20K or less, a high frequency high electric field is applied to the particle accelerator copper tube (particle acceleration tube 20 and particle deceleration tube 30) made of the particle accelerator copper material. Even when added, generation of Joule heat can be suppressed. Therefore, since the temperature rise of the particle acceleration tube 20 and the particle deceleration tube 30 is suppressed, it becomes possible to operate the particle accelerator 10 satisfactorily.
In addition, a higher voltage can be applied to the particle accelerator tube 20 and the particle deceleration tube 30 than before, and the performance of the particle accelerator 10 can be further improved.
Furthermore, although it is 6NCu, a residual resistance ratio (5000 or more) equivalent to that of normal 7NCu can be obtained, so that compared with the case where 7NCu, which is difficult to manufacture, is used, the copper tube for particle accelerator (particle Manufacturing costs of the acceleration tube 20 and the particle deceleration tube 30) can be greatly reduced.
In addition, the copper material for particle accelerators of the present invention in which the content of Fe, P, Al, As, Sn, and S is suppressed, for example, the 6N cathode has a content of Fe, P, Al, As, Sn, and S. It can be obtained by using a crucible of less than 1 ppm and dissolving and solidifying in a non-oxidizing atmosphere subjected to deoxidation and desulfurization treatment.

In addition, since the no-load gain coefficient Q is high and high-frequency power loss is suppressed, particles can be efficiently accelerated and decelerated, and the particle accelerator 10 itself can be downsized.
More specifically, in a conventional particle accelerator tube and particle decelerating tube made of 4NCu having a purity of Cu of 99.99 mass% or more and less than 99.999 mass%, when used at room temperature, the no-load gain coefficient Q is It was about 1/10000. In contrast, in the particle accelerating tube 20 and the particle decelerating tube 30 according to the present embodiment, the no-load gain coefficient Q is about 1/400000, and the high-frequency loss is reduced to 1/40.

According to the particle accelerator 10 according to the present embodiment, since the particle accelerator tube 20 and the particle decelerating tube 30 are made of 6NCu having a residual resistance ratio of 5000 or more, acceleration and deceleration of the electron beam 18 are efficient. The particle accelerator 10 itself can be downsized.
Further, since the electron beam 18 is sufficiently decelerated in the particle decelerating tube 30, generation of secondary particles such as neutrons is caused when the electron beam 18 that has passed through the particle decelerating tube 30 is absorbed by the beam dump 13. Therefore, the facility for shielding the particle accelerator 10 can be simplified. Specifically, since only X-rays of the same level as those of a medical X-ray device are generated, it can be used in the same manner as a normal medical X-ray device. More specifically, the electron beam 18 accelerated to about 100 MeV in the particle accelerating tube 20 can be decelerated to about 1 MeV in the particle decelerating tube 30, and generation of secondary particles such as neutrons can be suppressed. It becomes.
Furthermore, since the particle accelerator tube 20 and the particle decelerating tube 30 are made of a copper material for particle accelerator made of 6NCu, and the gas release from the inside is suppressed, the particle accelerator tube 20 and the particle decelerating tube can be relatively easily obtained. A vacuum atmosphere can be made relatively easily around the tube 30.

Furthermore, in this embodiment, since the waveguide 14 that connects the particle accelerator tube 20 and the particle deceleration tube 30 is made of the copper material for particle accelerator according to the present embodiment, the particle accelerator tube 30 collects the particles. The loss when supplying the high frequency power to the particle accelerating tube 20 can be suppressed.
Moreover, since the acceleration tube 20 and the deceleration tube 30 are comprised by the copper tube for particle accelerators of the same size (length, diameter), the high frequency electric power collect | recovered with the reduction tube 30 is efficiently made into the acceleration tube 20. It can be supplied and energy loss can be suppressed.
In the present embodiment, since the particle accelerating tube 20, the particle decelerating tube 30, and the waveguide 14 are accommodated in the same heat insulating vacuum vessel 17, the high frequency power loss is reduced by cooling to a very low temperature, and the high frequency Power can be reused reliably. At the same time, it is possible to reduce the size by integrating the heat insulating vacuum vessel 17 and to cool it efficiently.

  Further, the particle accelerating tube 20 and the particle decelerating tube 30 are connected to the coolers 25 and 35 via the connecting members 21 and 31, and are configured to be used in a cryogenic environment such as 20K or less. Since the members 21 and 31 are made of the copper material for particle accelerator according to the present embodiment having excellent thermal conductivity, the particle accelerator tube 20 and the particle deceleration tube 30 can be efficiently cooled. The configuration of the containers 25 and 35 can be simplified.

  According to the method for manufacturing a particle accelerator copper tube (particle acceleration tube 20 and particle deceleration tube 30) according to the present embodiment, after the final shape product is produced in the processing step S20, the final shape product is 400 ° C. Since the heat treatment for 1 hour or more is performed as described above, the strain accumulated in the final shape product by the processing step S20 can be surely released, and the copper tube for particle accelerator (particle acceleration tube 20 and particle deceleration tube 30). The residual resistance ratio (RRR) at can be increased.

  Further, in the processing step S20, the particle accelerating tube 20 and the particle decelerating tube are formed by diffusion bonding the constituent members (the first cylindrical member 41, the second cylindrical member 42, the disk-like member 43, and the block member 44). 30 is provided with a diffusion bonding step S23 for producing a final shape product of the shape of the copper tube for particle accelerator constituting 30. Therefore, the size and structure of the particle accelerator copper tube can be designed relatively freely. Become. Moreover, since the copper material for particle accelerators which is this embodiment is used, the structural members (the first cylindrical member 41, the second cylindrical member 42, the disk-shaped member 43, and the block member 44) are connected by diffusion bonding. While being able to join firmly, mixing of an impurity can be prevented reliably and it becomes possible to enlarge a residual resistance ratio (RRR).

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, in the present embodiment, the processing step S20 has been described as including the heat treatment step S30 that is held at 400 ° C. or more for 1 hour or more. However, the present invention is not limited to this, and even if the heat treatment conditions are different. The heat treatment may not be performed after the processing step S20.

Moreover, the shape and usage of the particle accelerator copper tubes (particle accelerator tube 20 and particle decelerator tube 30) are not limited to those shown in FIG. 2, and the particle accelerator copper tube used for the particle accelerator ( The particle accelerating tube 20 and the particle decelerating tube 30) may be used.
Furthermore, although it demonstrated as a structure which produces the 6NCu cathode by electrolytically treating the 4NCu cathode, it is not limited to this, Fe content is less than 0.1 ppm, P The content is less than 0.1 ppm, the Al content is less than 0.1 ppm, the As content is less than 0.1 ppm, the Sn content is less than 0.1 ppm, and the S content is less than 0.1 ppm, You may produce the ingot which consists of 6NCu in which the purity of Cu except a gas component was 99.9999 mass% or more and less than 99.99999 mass%.

The result of the confirmation experiment conducted to confirm the effect of the present invention will be described.
<Invention Example>
By performing electrolytic treatment using 4NCu cathode as a raw material, an ultra-high purity (6NCu) cathode having a purity of 99.9999 mass% or more and less than 99.99999 mass% was produced. Using a carbon crucible with a content of Fe, P, Al, As, Sn, and S of less than 1 ppm, the 6NCu cathode was dissolved in an Ar atmosphere subjected to deoxidation and desulfurization treatment, and an ingot (a billet having a diameter of 100 mm) was obtained. Produced.
After the obtained ingot was formed into a wire having a diameter of 1.0 mm and a length of 100 mm, heat treatment was performed to prepare samples of Invention Examples 1 to 10 shown in Table 1.

<Comparative example>
By performing electrolytic treatment using a 4NCu cathode as a raw material, an ultra-high purity (7NCu) cathode having a purity of 99.99999 mass% or more and less than 99.999999 mass% was produced.
And, various ingots (100 mm diameter billets) with adjusted impurity contents were produced by adding elements to the molten copper obtained by melting the 7NCu cathode under the same conditions as the present invention. did.
The obtained ingot was formed into a wire having a diameter of 1.0 mm and a length of 100 mm, and then subjected to heat treatment to produce samples of Comparative Examples 1 to 12 shown in Table 1.

  For the samples obtained as described above, the content of each element and the residual resistance ratio (RRR) were measured. The measurement results are shown in Table 1. The content of each element was measured by glow discharge mass spectrometry.

  Fe content less than 0.1 ppm, P content less than 0.1 ppm, Al content less than 0.1 ppm, As content less than 0.1 ppm, Sn content less than 0.1 ppm and In Example 1-10 of the present invention, in which the content of S was 6NCu having a content of less than 0.1 ppm, the residual resistance ratio (RRR) exceeded 3000.

  In particular, Fe content is less than 0.01 ppm, P content is less than 0.01 ppm, Al content is less than 0.01 ppm, As content is less than 0.01 ppm, Sn content is 0.01 ppm. In Examples 1 and 2 of the present invention, in which the content of S is less than 0.05 ppm and the content of S is less than 0.05 ppm, the residual resistance ratio (RRR) exceeds 6000, which is equivalent to Comparative Example 12 that is 7 NCu. .

  On the other hand, in Comparative Example 1-8 in which any one of Fe, P, Al, As, Sn, and S deviates from the scope of the present invention, the residual resistance ratios RRR are all less than 3000, It was confirmed that the electrical resistance at was not sufficiently reduced.

  Inventive Example 2, Inventive Example 3 and Comparative Example 9 are obtained by processing ingots having the same composition and changing the heat treatment conditions (temperature, time) after processing. When these are compared, it is confirmed that the residual resistance ratio (RRR) is greatly improved by increasing the heat treatment time after processing. In Comparative Example 9 where the heat treatment temperature was 300 ° C., the residual resistance ratio (RRR) remained as low as 1500.

  Further, Invention Example 4, Comparative Example 10 and Comparative Example 11 are obtained by processing ingots having the same composition and changing the heat treatment conditions (temperature, time) after processing. In Comparative Example 10 where the heat treatment time was 0.5 hours, the residual resistance ratio (RRR) was 2100, and in Comparative Example 11 where the heat treatment temperature was 300 ° C., the residual resistance ratio (RRR) was 1200.

  From these results, by increasing the heat treatment time or increasing the heat treatment temperature, it is possible to reliably release the strain accumulated during processing and to increase the residual resistance ratio (RRR). It was confirmed that.

10 Particle accelerator 12 X-ray generator (electromagnetic wave generator)
13 Beam dump 14 Waveguide 17 Thermal insulation vacuum vessel 18 Electron beam (particle beam)
20 Accelerating tube (copper tube for particle accelerator)
30 Reducer tube (copper tube for particle accelerator)
21, 31 Connection members 25, 35 Cooler S20 Processing step S23 Diffusion bonding step S30 Heat treatment step

Claims (7)

A particle accelerating tube that accelerates the particle beam, an electromagnetic wave generator that generates an electromagnetic wave using the accelerated particle beam, a particle decelerating tube that decelerates the particle beam that has passed through the electromagnetic wave generator, and the particle decelerating tube A particle accelerator comprising: a beam dump that absorbs the particle beam; and a cooler that cools the particle acceleration tube and the particle deceleration tube,
The particle accelerating tube and the particle decelerating tube are configured by diffusion bonding a first cylindrical member, a second cylindrical member, a disk-shaped member, and a block member made of a copper material for a particle accelerator,
In the particle accelerator copper material, the purity of Cu excluding gas components is 99.9999 mass% or more and less than 99.99999 mass%, Fe content is 0.04 ppm or less, and P content is 0.04 ppm. Hereinafter, the content of Al is 0.05 ppm or less, the content of As is 0.03 ppm or less, the content of Sn is 0.04 ppm or less, the content of S is 0.06 ppm or less, and Fe, P, Al, A particle accelerator characterized in that the content of impurities including As, Sn and S is 0.37 ppm or less , and the residual resistance ratio is 3000 or more. The copper material for particle accelerator has Fe content of less than 0.01 ppm, P content of less than 0.01 ppm, Al content of less than 0.01 ppm, As content of less than 0.01 ppm, Sn content The particle accelerator according to claim 1, wherein the content accelerator is less than 0.01 ppm, the S content is less than 0.05 ppm, and the residual resistance ratio is 5000 or more . The first cylindrical member, the second cylindrical member, the disk-shaped member, and the block member that are diffusion-bonded are subjected to heat treatment at 400 ° C or higher and lower than the melting point for 1 hour or longer. The particle accelerator described in 1. It comprises a waveguide connecting the particle accelerator tube and the particle deceleration tube, and is configured to supply high-frequency power recovered by the particle deceleration tube to the particle acceleration tube.
The particle accelerator according to any one of claims 1 to 3 , wherein the waveguide is made of the copper material for the particle accelerator. The particle accelerator according to claim 4, further comprising an adiabatic vacuum vessel that houses the particle accelerator tube, the particle deceleration tube, and the waveguide. 6. The particle accelerator according to claim 4 , wherein a length of the particle accelerator tube is the same as a length of the particle deceleration tube. The particle acceleration tube and said particle decelerating tube is connected to the condenser via a connecting member, the connecting member, from claim 4, characterized in that it is composed of a copper material for the particle accelerator The particle accelerator according to claim 6 .

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