Pressurization and straining apparatus, X-ray diffraction apparatus using the same, micro-Raman scattering measurement apparatus, and optical microscope.

Abstract

To provide a pressure / strain device capable of performing pressurization in one direction, and automatically measuring physical property evaluation of a sample from the one direction and a direction perpendicular to the one direction, an X-ray diffraction device using the pressure / strain device, a microscopic Raman scattering measurement device and an optical microscope.SOLUTION: A pressure / strain device of the present invention comprises first and second diamond anvils for holding a sample. The pressure / strain device comprises: a sample holding part in which the first diamond anvil rotates; a rotation mechanism that rotates the first diamond anvil; a pressing mechanism that mechanically applies pressure from the first diamond anvil side; an actuator that applies pressure by an electric signal to the second diamond anvil, and is hollow; a pressure sensor that detects a pressure applied to the sample held between the first and second diamond anvils; and a control mechanism that controls, and detects these operations.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pressurization / strain device, an X-ray diffractometer using the same, a microscopic Raman scattering measurement device, and an optical microscope. More specifically, the present invention relates to an ultrahigh-pressure pressurization / strain device using a diamond anvil, an X-ray diffractometer using the same, a microscopic Raman scattering measurement device, and an optical microscope.

Background Art

[0002] A diamond anvil cell (DAC) is known to generate extremely high pressures exceeding 1 million atmospheres. However, at pressures above 12 GPa, all substances become solids, so experiments under isotropic pressure are not possible, and experiments under differential stress are conducted instead. Therefore, it is also necessary to know the state of substances under strain / differential stress. Numerous evaluations of the physical properties of samples pressurized under high pressure have been carried out (for example, see Non-Patent Documents 1 to 7).

[0003] According to Non-Patent Document 1, a device is shown that applies rotational strain to a sample in a pressurized DAC by motor drive and performs X-ray diffraction in the pressurization axis direction. However, since it does not correspond to X-ray diffraction in the radial direction, information on the strain state cannot be obtained. According to Non-Patent Documents 2 and 3, although they have a rotation mechanism for the DAC, they do not correspond to X-ray diffraction in the radial direction.

[0004] Non-Patent Documents 4 and 5 disclose a pressurization device using a tungsten carbide anvil. However, tungsten carbide has low X-ray transmission ability and is not suitable for X-ray diffraction measurement under pressure.

[0005] According to Non-Patent Document 6, remote pressurization using a piezo actuator is realized. However, the dynamic range of pressure is small with only a piezo actuator. Furthermore, in Non-Patent Document 6, strain cannot be applied to the sample in the DAC. In Non-Patent Document 7, a pressurization mechanism using a gas pressure membrane and automatic pressurization using a piezo actuator independent thereof are realized, but there is still no rotation mechanism for applying strain.

Prior Art Documents

[0006] [Non-Patent Document 1] N. Novikov et al., Journal of Superhard Materials, 2015, Vol. 37, pp. 1-7 [Non-Patent Document 2] R. Nomura et al.,Review of Scientific Instruments,2017,Vol.88,Issue 4,pp.044501 [Non-Patent Document 3] V. Blank et al., Physics Letters A, 1994, Vol. 188, Issue 3, pp. 281-286 [Non-Patent Document 4] H. Razavi-Khosroshahi et al., Journal of Materials Chemistry A, 2017, Vol. 5, Issue 38, pp. 20298-20303 [Non-Patent Document 5] RZValiev et al., JOM, 2006, Vol. 58, Issue 4, pp. 33-39 [Non-Patent Document 6] William J. Evans et al.,Review of Scientific Instruments,2007,78,073904 [Non-Patent Document 7] Stanislav V. Sinogeikin et al.,Review of Scientific Instruments,2015,86,072209 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Therefore, the object of the present invention is to provide a pressurization and straining device capable of automatically measuring the physical properties of a sample from a uniaxial direction and a direction perpendicular thereto while applying pressure in a uniaxial direction and rotating in a direction perpendicular thereto, as well as an X-ray diffractometer, a micro-Raman scattering measuring device, and an optical microscope using the same. [Means for solving the problem]

[0008] The pressurizing and straining device according to the present invention comprises first and second diamond anvils for holding a sample, a sample holding section on which the first diamond anvil rotates, a rotation mechanism for rotating the first diamond anvil, a hollow actuator that applies pressure by an electrical signal from the first diamond anvil side, a pressing mechanism that applies mechanical pressure from the second diamond anvil side, a pressure sensor for detecting the pressure applied to the sample held by the first and second diamond anvils, and a control mechanism that controls the operation of the rotation mechanism, the actuator, and the pressing mechanism and detects the operation of the pressure sensor, the rotation mechanism comprises a drive unit and a hollow rotating shaft that rotates by the drive unit, the sample holding section comprises a hollow first support base that is joined to and fixes the first diamond anvil, and a support for the first support base, The invention provides a first support base which is hollow and includes a pressure transmission part that receives pressure from the actuator and transmits it to the first diamond anvil, a rotating part that is joined to the first support base and rotates in engagement with the rotating shaft, and a bearing that resists the load received from the pressure transmission part and rotates the rotating part; a second hollow support base which is joined to the second diamond anvil and fixes the second diamond anvil; a second hollow support base which supports the second support base and receives pressure from the pressing mechanism and transmits it to the second diamond anvil; and a cylinder which holds the first support base, the first support base, the second support base, and the second support base while exposing the first and second diamond anvils, wherein the rotating shaft is located inside the actuator and engages with the rotating part of the first support base, rotating the first diamond anvil, thereby achieving the above objective. There is a step between the pressure transmission section and the rotating section, and the pressure transmission section may be convex relative to the rotating section. The pressing mechanism may be selected from the group consisting of a stepping motor, a hydraulic piston, and a gas pressure membrane. The actuator may be a stacked piezoelectric actuator. The stroke of the actuator may be in the range of 50 μm to 200 μm. The pressure sensor may be a quartz piezoelectric sensor. The drive unit comprises a stepping motor that generates torque and an arm that transmits the torque to the rotating shaft by gears, and the arm may rotate relative to the rotating shaft. The control mechanism may control the operation of the rotating mechanism, the pressing mechanism, and the actuator, and detect the operation of the pressure sensor, such that (A) the pressing mechanism applies pressure to the sample from the second diamond anvil side, (B) while pressure is applied to the sample, the pressure sensor measures the pressure value from the actuator and adjusts the actuator to set the pressure starting point for the actuator, (C) while pressure is applied to the sample, the actuator adjusted to the pressure starting point continuously applies pressure from the first diamond anvil side, and (D) while pressure is applied to the sample, the rotating mechanism rotates the first diamond anvil. The system may further include a positioning mechanism for determining the position of the sample, the positioning mechanism comprising a lower stage, support legs connected to the first support base for adjusting the position of the sample, and a backing plate that contacts the second support base. The device may further include a deflection mechanism connected to the lower stage, which changes the horizontal orientation of the pressurizing and straining device. The deflection mechanism may adjust the horizontal and vertical positions of the sample. The control mechanism may further control the operation of the steering mechanism. The control mechanism may include an actuator drive circuit that applies an electrical signal to the actuator, a conversion and measurement unit that converts and measures the pressure of the pressure sensor, a pressing drive circuit that sends a drive signal to the pressing mechanism, a rotation drive circuit that sends a drive signal to the rotation mechanism, and a central processing unit that controls the actuator drive circuit, the conversion and measurement unit, the pressing drive circuit, and the rotation drive circuit. The rotational drive circuit may further include a pulse generator connected to it. The X-ray diffraction apparatus according to the present invention is equipped with the above-mentioned pressurizing and straining device, thereby solving the above-mentioned problems. The micro-Raman scattering measurement apparatus according to the present invention is equipped with the above-mentioned pressurizing and straining apparatus, thereby solving the above-mentioned problems. The optical microscope apparatus according to the present invention is equipped with the above-described pressurizing and straining device, thereby solving the above-mentioned problems. [Effects of the Invention]

[0009] The pressurizing and straining device of the present invention comprises a pressing mechanism that applies pressure mechanically and an actuator that applies pressure using an electrical signal. Therefore, continuous pressurization by the actuator and stepwise increasing pressurization by the pressing mechanism are used in combination, allowing for the continuous application of a large dynamic range of pressure to the sample in the uniaxial direction (i.e., the pressurizing direction). With such pressure applied, the first diamond anvil is rotated by the rotation mechanism, so that the sample is subjected to rotation in a direction perpendicular to the uniaxial direction (radial direction), thereby applying strain to the sample. The operation of these rotation mechanism, actuator, and pressing mechanism is controlled by a control mechanism in conjunction with the detection of pressure by a pressure sensor, so that pressure application and strain application to the sample can be performed automatically.

[0010] Furthermore, since the pressurizing and straining apparatus of the present invention has hollow first and second support bases, actuators, and a rotating shaft that engages with the first support base, it is possible to incident X-rays in a uniaxial direction, for example, and perform X-ray diffraction measurements of the sample. Also, since the first and second diamond anvils are exposed in the sample holding section, it is possible to incident X-rays from a direction perpendicular to the uniaxial direction and perform X-ray diffraction measurements of the sample in the radial direction.

[0011] By combining the pressurizing and straining device of the present invention with an X-ray source, light source, light receiving unit for receiving scattered and diffracted light, detector, etc., an X-ray diffractometer and a microscope Raman scattering measurement device can be provided. Furthermore, by combining the pressurizing and straining device of the present invention with a microscope, an optical microscope device can be provided. [Brief explanation of the drawing]

[0012] [Figure 1] Schematic diagram showing the pressurization and distortion device of the present invention [Figure 2] Schematic diagram showing the rotation mechanism of the present invention [Figure 3] Schematic diagram showing the positioning mechanism [Figure 4] Block diagram showing the control mechanism applied to the pressurization and distortion device of the present invention [Figure 5] Diagram showing the relationship between the load monitored by the pressure sensor and the generated pressure in Reference Example 1 [Figure 6] Diagram showing an enlarged view of the region A in FIG. 5 [Figure 7] Diagram showing an enlarged view of the region B in FIG. 5 [Figure 8] Diagram showing the uniaxial X-ray diffraction pattern in Reference Example 1 [Figure 9] Diagram showing the radial X-ray diffraction pattern in Reference Example 1 [Figure 10] Diagram showing the relationship between the load monitored by the pressure sensor and the generated pressure in Example 1 [Figure 11] Diagram showing an enlarged view of the region C in FIG. 10 [Figure 12] Diagram showing the uniaxial X-ray diffraction pattern in Example 1 [Figure 13] Diagram showing the radial X-ray diffraction pattern in Example 1

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same elements are denoted by the same reference numerals, and the description thereof will be omitted.

[0014] The pressurization and distortion device of the present invention will be described. FIG. 1 is a schematic diagram showing the pressurization and distortion device of the present invention.

[0015] The pressurizing and straining device 100 of the present invention comprises first and second diamond anvils 111 and 112 for holding a sample 11X, a sample holding section 110 on which the first diamond anvil 111 rotates, a rotation mechanism 120 for rotating the first diamond anvil 111, a hollow actuator 130 that applies pressure by an electrical signal from the first diamond anvil 111 side, a pressing mechanism 140 that mechanically applies pressure from the second diamond anvil 112 side, a pressure sensor 150 for detecting the pressure applied to the sample 11X held by the first and second diamond anvils 111 and 112, and a control mechanism 160 that controls the operation of at least the rotation mechanism 120, actuator 130, and pressing mechanism 140, and further detects the operation of the pressure sensor 150.

[0016] The pressurizing and straining device 100 of the present invention can continuously apply a large dynamic range of pressure to the sample 11X in a uniaxial direction (horizontal direction in Figure 1) by combining continuous pressurization based on an electrical signal from the actuator 130 and gradual, large mechanical pressurization from the pressing mechanism 140.

[0017] With such pressure applied, the first diamond anvil 111 is rotated by the rotation mechanism 120, so that the sample 11X is subjected to rotation in a direction perpendicular to the uniaxial direction (radial direction), and strain can be applied to the sample 11X. The operation of these rotation mechanism 120, actuator 130, and pressing mechanism 140 is controlled by the control mechanism 160 in conjunction with the detection by the pressure sensor 150, so that pressure is applied to the sample 11X and strain is applied automatically. In this specification, a device that can apply not only pressure but also strain to a sample is referred to as a pressure and strain device, but the device of the present invention may also be called a strain-applying pressure device or a high-pressure strain application device.

[0018] The following sections will provide a detailed explanation of each component. The first and second diamond anvils 111 and 112 are designed to clamp the sample 11X via a gasket 11Y. The clamping ends of the first and second diamond anvils 111 and 112 are flat, and the smaller the area, the greater the load applied to the sample 11X. The clamping end of the first diamond anvil 111 is preferably circular, and the clamping end of the second diamond anvil 112 is polygonal, such as a square, hexagon, or octagon. This allows only the first diamond anvil 111 to rotate easily by the rotation mechanism 120, thereby applying radial rotation to the sample 11X. The sample 11X may be held together with a pressure medium such as sodium chloride (NaCl) and a standard sample such as gold.

[0019] The sample holding section 110 includes a first support base 113 that is joined to and fixes the first diamond anvil 111, a first support base 114 that supports the first support base 113, a second support base 118 that is joined to and fixes the second diamond anvil 112, a second support base 119 that supports the second support base 118 and receives pressure from the pressing mechanism 140 and transmits this pressure to the second diamond anvil 112, and a cylinder 11 that holds the first support base 113, the first support base 114, the second support base 118, and the second support base 119.

[0020] The first support base 113, the first support base 114, the second support base 118, and the second support base 119 are all hollow, which allows for, for example, X-ray diffraction measurement of the sample 11X when irradiated with X-rays from the horizontal direction as shown in Figure 1, or enables in-situ observation in combination with a microscope.

[0021] Furthermore, the first and second diamond anvils 111 and 112 held in the sample holding section 110 transmit light across a very wide wavelength range from 220 nm to terahertz, millimeter waves, and even microwaves. For example, an infrared laser can be irradiated from the second diamond anvil 112 side to heat the sample 11X under high pressure, or monochromatic light can be incident to measure the Raman scattering spectrum of the sample 11X under high pressure.

[0022] The cylinder 11 holds the first and second diamond anvils 111 and 112 in an exposed state, allowing X-ray diffraction measurement to be performed by irradiating the high-pressure sample 11X, which is held between the first and second diamond anvils 111 and 112, with X-rays from a direction perpendicular to the uniaxial direction (radial direction). In Figure 1, for ease of viewing, the radial direction is indicated by an arrow pointing upward from the bottom of the paper, but in reality, it is intended to be a direction perpendicular to the plane of the paper.

[0023] The cylinder 11 may be configured to hold the first and second support bases 113 and 118 by set screws 11Z. This allows for fine horizontal positioning of the sample 11X.

[0024] The first support base 114 includes a pressure transmission unit 115 that receives pressure from the actuator 130 and transmits that pressure to the first diamond anvil 111, a rotating unit 117 that is joined to the first support base 113 and rotates in engagement with the rotating shaft 122 (described later), and a bearing 116 that resists the load received from the pressure transmission unit 115 and rotates the rotating unit 117. There is a step between the pressure transmission unit 115 and the rotating unit 117, and the pressure transmission unit 115 may be convex relative to the rotating unit 117. As a result, the actuator 130 does not make surface contact with the rotating unit 117 via the bearing 116, so the rotating unit 117 can rotate effectively without being hindered by the pressure from the actuator 130.

[0025] The first and second support bases 113 and 118 are preferably made of a hard material such as tungsten carbide. This allows the first and second diamond anvils 111 and 112 to be fixed in place. The first and second support bases 113 and 118 are preferably fixed and positioned to the rotating part 117 and the second support base 119, respectively, by set screws 11Z such as hex socket set screws.

[0026] The actuator 130 is not particularly limited as long as it can convert an external electrical signal into physical expansion and contraction motion, but typically it is a piezoelectric element that converts voltage as an electrical signal into force. In particular, it may be a multilayer piezoelectric actuator. If it is a multilayer type, expansion and contraction in the range of several nanometers to several hundred micrometers is possible depending on the number of layers of piezoelectric elements when a voltage is applied. Such expansion and contraction on the order of nanometers enables continuous pressurization that is different from that of the pressing mechanism 140. Such piezoelectric elements consist of a multilayer structure of lead zirconate titanate (PZT, Pb(Zr,Ti)O3), potassium niobate (KNN, (K,Na)NbO3), etc.

[0027] There are limitations to the stroke (i.e., the maximum extension / retraction width) of the actuator 130. However, if the stroke is short, the interlock with the pressing mechanism 140 can be controlled more, and if the stroke is long, the interlock with the pressing mechanism 140 can be controlled less. The stroke of the actuator 130 is preferably in the range of 50 μm to 200 μm. Within this range, a pressurizing and straining device capable of continuous pressurizing up to ultra-high pressure (up to 350 GPa) can be provided without the need for a special actuator. Among these, actuators having a stroke in the range of 60 μm to 100 μm are readily available.

[0028] The actuator 130 may be mounted in the cylinder tube 131 with a rotating shaft 122 inside, and the actuator 130 can be positioned within the cylinder tube 131 in accordance with the extension and retraction of the actuator 130. One end of the cylinder tube 131 is fitted into the pressure transmission section 115 of the first support base 114, efficiently applying the pressure from the actuator 130 to the first diamond anvil 111. A cylindrical connecting section 132 may be attached to the other end of the cylinder tube 131. The cylindrical connecting section 132 may cover a pressure sensor 150 provided on the actuator 130.

[0029] The pressing mechanism 140 is not particularly limited as long as it mechanically applies pressure to the second diamond anvil 112. In this specification, mechanically applying pressure means applying pressure to the second diamond anvil 112 using the principle of leverage, spring force, screw force, gas pressure, hydraulic pressure, etc., and is intended to apply pressure in a stepwise and dynamic manner.

[0030] In the following explanation, the pressing mechanism 140 in Figure 1 is assumed to be a hollow gas pressure membrane connected to an external gas (not shown) and, if necessary, a pressure booster. However, in addition to a gas pressure membrane, a stepping motor or a hydraulic piston can also be used.

[0031] By using the actuator 130 and the pressing mechanism 140 in combination, the intervals between the minimum pressure steps applied by the pressing mechanism 140 can be filled in 0.1% steps. For example, the pressing mechanism 140 can achieve a large dynamic range of 2 GPa to 350 GPa, and the actuator 130 can fill in the pressure in between in 0.1% steps, enabling continuous pressurization.

[0032] The pressure sensor 150 is not particularly limited as long as it detects the pressure applied to the sample 11X between the first and second diamond anvils 111 and 112 by the actuator 130 and / or the pressing mechanism 140, but examples include a quartz pressure sensor, a strain gauge pressure sensor, and a semiconductor pressure sensor. Among these, a quartz piezoelectric sensor that utilizes the piezoelectric effect is preferred because it can measure high loads and can be used repeatedly.

[0033] By using the pressure sensor 150, the pressurization start point of the actuator 130 can be set. Specifically, the applied voltage and position of the actuator 130 are adjusted in accordance with the change in the pressure value detected by the pressure sensor 150, so that the point at which the pressure value detected by the actuator 130 is 0 and the point at which the pressure value begins to be detected becomes the pressurization start point of the actuator 130. Continuous pressurization is always possible for the stroke length of the actuator 130 from the set pressurization start point.

[0034] Naturally, using the pressure sensor 150, it is also possible to detect when the stroke of the actuator 130 reaches its maximum value and set a pressurization termination point. From the set pressurization termination point, continuous depressurization is also possible for the length of the actuator 130's stroke.

[0035] Figure 2 is a schematic diagram showing the rotation mechanism of the present invention.

[0036] The rotating mechanism 120 comprises a drive unit 121 and a rotating shaft 122 that is rotated by the drive unit 121. The rotating shaft 122 is hollow and is positioned to be mounted within a hollow actuator 130, and is engaged with the rotating part 117 of the first support base 114 by fitting it into place. The torque generated by the drive unit 121 causes the rotating shaft 122 to rotate. Subsequently, along with the rotation of the rotating shaft 122, the rotating part 117, the first support base 113 and the first diamond anvil 111 joined to it rotate, causing the sample 11X to rotate in the radial direction. As a result, radial strain is applied to the sample 11X.

[0037] The drive unit 121 preferably includes a stepping motor 210 that generates torque, a spur gear 220 that transmits torque to the rotating shaft 122, and a rotatable arm 230. The arm 230 is rotatably fixed to the stepping motor 210 by bolts 240 and rotates relative to the rotating shaft 122. The rotation of the arm 230 facilitates loading the rotating shaft 122 into the actuator 130. The spur gear 220 may be covered and protected by a spur gear cover 250.

[0038] Figure 3 is a schematic diagram showing the positioning mechanism.

[0039] The pressurizing and straining device 100 of the present invention may further include a positioning mechanism 300 for determining the position of the sample 11X. This allows for precise adjustment of the horizontal and vertical (here, the up and down directions on the plane of the paper in Figure 1) position of the sample 11X. As a result, various measurements, such as X-ray diffraction measurements, can be accurately performed on the same position of the sample 11X in both the horizontal and radial directions.

[0040] As shown in Figure 3, the positioning mechanism 300 comprises a lower stage 310, a support leg 320 (hereinafter simply referred to as the support leg with fine adjustment screw) connected to a first support base 114 and equipped with a fine adjustment screw 32X for adjusting the position of the sample 11X, and a contact plate 330 that contacts a second support base 119. The support leg with fine adjustment screw 320 and the contact plate 330 are fixed to the lower stage 310.

[0041] The support leg 320 with a fine adjustment screw is connected to the first support base 114 by a push-pull screw. This allows for fine horizontal movement. The support leg 320 with a fine adjustment screw may also be connected to the cylinder tube 131 in addition to the first support base 114. This allows for stable fine vertical movement.

[0042] The pressurizing and straining apparatus 100 of the present invention may further include a deflection mechanism 340 connected to the lower stage 310. The deflection mechanism 340 is rotatable and can change the horizontal orientation of the pressurizing and straining apparatus 100. This enables various measurements, such as X-ray diffraction measurements in the horizontal and radial directions, to be performed automatically. The deflection mechanism 340 may be capable of controlling the horizontal and vertical position of the sample 11X. Such a deflection mechanism 340 may be configured to include one or more stages and encoders.

[0043] Refer to Figure 1 again. As described above, the control mechanism 160 controls the operation of the rotation mechanism 120, the actuator 130, and the pressing mechanism 140, and detects the operation of the pressure sensor 150, so that the pressurizing and straining device 100 can automatically apply pressure and strain to the sample 11X.

[0044] In detail, the control mechanism 160 controls the operation as follows: Operation (A): First, the pressing mechanism 140 applies mechanical pressure to the sample 11X from the second diamond anvil 112 side. If the pressing mechanism 140 is a gas pressure membrane, gas can be introduced from an external gas (not shown).

[0045] Operation (B): With mechanical pressure applied to the sample 11X by the pressing mechanism 140, the pressure sensor 150 measures the pressure value from the actuator 130 and adjusts the actuator 130 to set the pressure starting point for the actuator 130. Preferably, at this time, the stroke of the actuator 130 is 0, meaning it is not extended at all. In this way, the pressure starting point of the actuator 130 is set.

[0046] For example, if actuator 130 is applying pressure, the applied voltage is adjusted to set the stroke of actuator 130 to zero, so that it is just before pressurization. For example, if actuator 130 is not applying pressure, the position of actuator 130 inside the cylinder tube 131 is adjusted to position it just before pressurization. In this case as well, the stroke of actuator 130 is zero.

[0047] Operation (C): Next, with the pressing mechanism 140 applying pressure to the sample 11X, the actuator 130, which has been adjusted to the pressurization start point, continuously applies pressure to the first diamond anvil 111. For example, if the actuator 130 is a stacked piezo actuator, pressure can be applied to the first diamond anvil 111 only by gradually applying voltage, up to the stroke of the actuator 130. However, by controlling the amount of extension and retraction of the actuator 130, pressure can be applied more precisely within the stroke.

[0048] Operation (D): With mechanical pressure and electrical signal pressure applied to the sample 11X, the rotation mechanism 120 rotates the first diamond anvil 111. This applies radial strain to the sample 11X.

[0049] Prior to operation (D), the control mechanism 160 can continuously apply pressure to the sample 11X up to ultra-high pressure (e.g., 350 GPa) by repeatedly applying mechanical pressure by the pressing mechanism 140 and electrical pressure by the actuator 130, following the aforementioned operations (A) to (C) of the pressing mechanism 140, actuator 130, and pressure sensor 150.

[0050] Operation (E): The control mechanism 160 applies additional pressure to the second diamond anvil 112 side with the pressing mechanism 140 while the actuator 130 is applying pressure to the first diamond anvil 111 side. For example, if the actuator 130 is a multilayer piezo actuator and the pressing mechanism 140 is a gas pressure membrane, then gas can be introduced while maintaining the voltage applied to the multilayer piezo actuator. As a result, the actuator 130 and the first diamond anvil 111 are brought into physical proximity, and the pressure from the actuator 130 is further applied to the first diamond anvil 111 side.

[0051] Prior to operation (E), the voltage to the actuator 130 may be removed to reduce the pressure applied to the first diamond anvil 111. Alternatively, this pressure reduction may be performed continuously for the stroke length of the actuator 130.

[0052] Operation (F): Next, with the pressing mechanism 140 applying further pressure to the second diamond anvil 112, the pressure sensor 150 adjusts the actuator 130 so that it detects the pressure applied by the actuator 130 to the first diamond anvil 111 and begins to detect that pressure value. This operation (F) is the same as operation (B) described above.

[0053] Operation (G): Next, with the pressing mechanism 140 applying further pressure to the sample 11X, the actuator 130, which has been adjusted again to the pressure start point, continuously applies pressure to the first diamond anvil 111 side. Operation (G) is the same as operation (C), but the pressure applied by the pressing mechanism 140 is different. Therefore, in the new pressure range, the pressure can be applied more precisely by controlling the amount of extension and contraction of the actuator 130.

[0054] In this way, by repeating operations (E) to (G), pressure can be continuously applied up to ultra-high pressure (e.g., 350 GPa). Using the pressurizing and straining device 100 of the present invention, pressure can be applied until the first and second diamond anvils 111 and 112 break, and the endpoint of the break can be specified. Here, the operation of pressurizing up to ultra-high pressure has been described, but it will be easily understood by those skilled in the art that it is also possible to continuously reduce pressure from ultra-high pressure by setting the maximum value of the stroke as the depressurization start point instead of the pressurizing start point where the stroke of actuator 130 is 0, and performing the reverse operation.

[0055] Furthermore, by performing operation (D) at the desired pressures of operations (E) to (G), information regarding the strain state of the sample under any given pressure can be obtained.

[0056] The control mechanism 160 may further control the operation of the deflection mechanism 340. By combining the pressurizing and straining device 100 of the present invention with, for example, an X-ray source and an X-ray detector, information regarding the strain state of the sample 11X in the radial direction as well as the horizontal direction can be automatically obtained.

[0057] Figure 4 is a block diagram showing the control mechanism applied to the pressurizing and straining device of the present invention.

[0058] The control mechanism 160 includes at least an actuator drive circuit 410 that applies an electrical signal such as voltage to the actuator 130, a conversion and measurement unit 420 that converts and measures the pressure of the pressure sensor 150, a pressing drive circuit 430 that sends a drive signal such as a drive current to the pressing mechanism 140, a rotation drive circuit 460 that sends a drive signal such as a drive current to the rotation mechanism 120, and a central processing unit 440 that controls the actuator drive circuit 410, the conversion and measurement unit 420, the pressing drive circuit 430, and the rotation drive circuit 460. This enables pressurization up to ultra-high pressure by the above-described operations (A) to (G), or vice versa, depressurization from ultra-high pressure, as well as the application of radial strain to the sample.

[0059] A function generator 450 may be further connected to the actuator drive circuit 410. This allows the actuator drive circuit 410 to amplify the pulse voltage, which has the waveform (pulse signal) of the electrical signal output from the function generator 450, and apply it to the actuator 130. In other words, since the voltage can be continuously applied to the actuator 130 according to the pulse width, continuous pressurization or depressurization is possible. For example, if a 1 Hz pulse voltage is used, the voltage can be applied with a 1-second period, enabling periodic pressurization or depressurization. The function generator may also be a pulse generator. Furthermore, the actuator drive circuit 410 may be equipped with a voltage amplification function that amplifies and outputs the pulse voltage.

[0060] The conversion and measurement unit 420 is not particularly limited as long as it converts the pressure from the pressure sensor 150 into an electrical signal such as an electric charge and measures it. For example, a charge amplifier can be used as the conversion and measurement unit 420.

[0061] The pressing drive circuit 430 sends a drive signal (e.g., a drive current) to the pressing mechanism 140 to activate the pressing mechanism 140. For example, if the pressing mechanism 140 is a gas pressure membrane, preferably the pressing drive circuit 430 is a pressure controller, and the gas pressure supplied to the gas pressure membrane is increased or decreased by an electrical signal from the pressure controller, controlling the mechanical pressure applied to the second diamond anvil 112.

[0062] The rotary drive circuit 460 sends a drive signal (e.g., a drive current) to the rotary mechanism 120 to operate it, but preferably a pulse generator 470 is also connected. The pulse generator 470 provides a pulse signal to the rotary drive circuit 460, and by adjusting the frequency of the pulse signal, the torque of the stepping motor 210 (Figure 2) of the rotary mechanism 120 is adjusted. The generated torque is transmitted to the rotating shaft 122 via the spur gear 220 (Figure 2), and together with the first diamond anvil 111, it applies radial strain to the sample 11X.

[0063] The central processing unit 440 may include a memory (not shown) that stores a program for repeatedly applying mechanically stepped pressure by the pressing mechanism 140 and applying minute, continuous electrical pressure by the actuator 130, and a program for rotating the first diamond anvil 111 by the rotation mechanism 120 at a predetermined pressure. This allows for automatic pressurization up to ultra-high pressure (e.g., 350 GPa) and depressurization from ultra-high pressure, as well as the application of radial strain to the sample 11X at a desired pressure. Furthermore, the drive signal (drive current) for the pressing mechanism 140 and the pulse signals for the actuator 130 and / or rotation mechanism 120 may be set via an input device (not shown) such as a keyboard or touch panel, and these settings may be stored in the memory.

[0064] Such a central processing unit 440 may be configured by hardware logic, or it may be implemented by software using a personal computer equipped with a CPU (Central Processing Unit).

[0065] Furthermore, if the pressurizing and straining device 100 is further equipped with a steering mechanism 340, the control mechanism 160 may further be equipped with a steering drive circuit (not shown) that sends a drive signal such as a drive current to the steering mechanism 340, and a program for changing the orientation of the pressurizing and straining device 100 may be stored in the memory of the central processing unit 440.

[0066] As described above, by equipping the pressurizing / straining device 100 of the present invention with various light sources, such as an X-ray source, a light-receiving unit for receiving scattered or diffracted light, and a detector, an X-ray diffractometer or micro-Raman scattering measuring device capable of measuring the physical properties of a sample subjected to high pressure and strain can be constructed. Furthermore, by mounting the pressurizing / straining device 100 of the present invention on a microscope, an optical microscope device capable of observing a sample subjected to high pressure and strain can be provided. Naturally, multiple of these various measuring devices may be combined.

[0067] The present invention will now be described in detail using specific examples, but please note that the present invention is not limited to these examples. [Examples]

[0068] [Pressure / Strain Device] The pressurizing and straining device 100 shown in Figure 1 was constructed as follows. Diamond anvils with a tip diameter of 0.3 mm were used as the first and second diamond anvils 111 and 112. The tips of the first and second diamond anvils 111 and 112 were both flat, but the tip of the first diamond anvil 111 was machined to be circular, and the tip of the second diamond anvil 112 was machined to be octagonal. The first and second diamond anvils 111 and 112 were joined to hollow first and second support bases 113 and 118, respectively, which were made of tungsten carbide. The first and second support bases 113 and 118 were fixed to the rotating part 117 and the second support base 119, respectively, by hex socket set screws 11Z.

[0069] Here, the first support base 113 was held on a first support base 114 which included a pressure transmission section 115 that receives pressure from an actuator described later, a bearing 116, and a rotating section 117 that rotates in engagement with a rotating shaft. The rotation of the rotating section 117 made it possible to rotate the first diamond anvil 111 together with the first support base 113. On the other hand, the second support base 118 was coupled to a second support base 119 that receives pressure from a pressing mechanism 140 described later. The first and second support bases 113 and 118 and the first and second support bases 114 and 119 were held by a stainless steel cylinder 11 with the first and second diamond anvils 111 and 112 exposed, forming a sample holding section 110.

[0070] A gas pressure membrane (manufactured by DIAX) was installed on the second support base 118 side as the pressing mechanism 140. The gas pressure membrane was connected to argon gas (not shown), and the gas pressure was adjusted by a pressure controller (GE PACE5000) as the pressing drive circuit 430. This was connected to a personal computer equipped with a CPU as the central processing unit 440.

[0071] Actuator 130 is a hollow laminated piezoelectric actuator (Piezosys The piezo actuator (manufactured by tem Jena GmbH, HPSt 1000 / 25-15 / 80 VS35, lead zirconate titanate, stroke length: 80 μm) was placed in the cylinder tube 131, with a portion of it housed in the sample holder 110. A piezo actuator amplifier (manufactured by Piezosystem Jena GmbH, SVR 1000) 410 and a function generator 450 (manufactured by NF Circuit Design Block Co., Ltd., WF1973) were connected to the actuator drive circuit 410, and this was connected to a computer.

[0072] A quartz piezoelectric sensor (HBK, CLP / 62KN) was installed in the cylinder tube as pressure sensor 150, and the load from the gas pressure membrane and piezo actuator was measured. A piezoelectric sensor amplifier (HBK, CMD600) was connected as conversion measurement unit 420 and connected to a computer via an Ethernet hub. The pressure change (load change) was determined from the gold lattice constant by X-ray diffraction (e.g., Taku Tsuchiya, JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 108, NO. B10, 2462, 2003).

[0073] The rotating mechanism 120 included a geared stepping motor (Oriental Motor Co., Ltd., PK564BW-H1005) as the drive unit 121 and a hollow rotating shaft 122 that rotated by its torque. The rotation drive circuit 460 was a stepping motor driver connected to a pulse generator (Tsuji Electronics PM16C-04XDL). The rotating shaft 122 was mounted inside a hollow actuator 130 and engaged with the rotating part 117. The stepping motor's rotation drive circuit 460 was connected to a computer.

[0074] The control mechanism 160 includes a piezo actuator amplifier, a function generator, a piezoelectric sensor amplifier, a pressing drive circuit (gas pressure membrane circuit), a rotation drive circuit (rotating mechanism circuit), and a CPU, which control the operation of the rotating mechanism 120, the pressing mechanism 140, and the actuator 130, and detect the operation of the pressure sensor 150.

[0075] The pressurizing and straining device 100 further includes a positioning mechanism comprising a lower stage 310, support legs 320 with fine adjustment screws, and a backing plate 330, to position the sample.

[0076] [Reference example 1] In Reference Example 1, in the constructed pressurizing and straining apparatus, a mixture of gold and BaF2 (barium fluoride) was set in the hole in the center of gasket 11Y as sample 11X, and the physical properties of the sample were investigated when pressure was applied to the sample without rotating the first diamond anvil.

[0077] The first and second diamond anvils 111 and 112 were mechanically pressurized to approximately 2 GPa using a gas pressure membrane. Next, the pressurization start point of the piezo actuator was adjusted using a quartz piezoelectric sensor. Subsequently, a pulse signal (piezo voltage) generated by a function generator was input to a piezo actuator amplifier, and a voltage 120 times greater was supplied to the piezo actuator, extending the actuator and pressurizing the first diamond anvil 111. The piezo voltage was pressurized and fixed at 1175 V, and then mechanically pressurized again using a gas pressure membrane. The pressure changes on the sample obtained in this way are shown in Figures 5 to 7. X-ray diffraction measurements were performed in the uniaxial direction (horizontal direction in Figure 1) and radial direction (perpendicular to the plane of the paper in Figure 1) when each pressure was applied. These results are shown in Figures 8 and 9.

[0078] [Example 1] In Example 1, a pressurizing and straining device was used that was further equipped with a steering mechanism 340, making it rotatable. Specifically, the lower stage 310 of the pressurizing and straining device was connected to a steering mechanism 340 that combined various stages for adjusting the position in the X, Y, and Z axes with a rotary encoder and a ring-type precision encoder.

[0079] In a rotatable pressurizing and straining apparatus, a mixture of gold and BaF2 (barium fluoride) was set as sample 11X in the hole at the center of gasket 11Y. Pressure was applied to the sample, and the physical properties of the sample were investigated while the first diamond anvil was rotated. A 180° rotational strain was applied to the sample while pressure was applied, and then another 180° (total 360°) rotational strain was applied. These operations were performed automatically. The pressure changes and the results of X-ray diffraction measurements from the uniaxial direction and radial direction (perpendicular to the plane of the paper in Figure 1) are shown in Figures 10 to 13.

[0080] These results will be summarized and explained below. Figure 5 shows the relationship between the load monitored by the pressure sensor and the generated pressure in Reference Example 1. Figure 6 is a magnified view of area A in Figure 5. Figure 7 is a magnified view of area B in Figure 5.

[0081] As shown in Figure 5, it can be seen that the pressurizing and straining device of the present invention allows for continuous pressurization of a sample in a uniaxial direction (horizontal direction in Figure 1). In detail, region A in Figure 5 shows electrical pressurization by an actuator, and region B in Figure 5 shows mechanical pressurization by a gas pressure membrane, with a large dynamic range of 2 GPa to 10 GPa. Figure 6 shows the change in pressure when the piezoelectric voltage is changed, with sample numbers BaF3-1 to BaF3-11 for each piezoelectric voltage. Figure 7 shows the change in pressure when the piezoelectric voltage is fixed at 1175 V and the gas pressure is changed, with sample numbers BaF3-12 to BaF3-18 for each gas pressure.

[0082] Figure 8 shows the uniaxial X-ray diffraction pattern in Reference Example 1. Figure 9 shows the X-ray diffraction pattern in the radial direction in Reference Example 1.

[0083] As shown in Figure 8, it was found that BaF2 retains a fluorite-type structure below 3.6 GPa, but completely transforms into a cotunnite-type structure above 3.6 GPa. From this, it was found that, when rotational strain is not applied to the sample, a pressure of 3.6 GPa or higher is required for the phase transition from the fluorite-type structure to the cotunnite-type structure.

[0084] Figure 9 shows the Debye diffraction pattern unfolded for each direction, where the "undulation" in the diffraction lines indicates the degree of strain. The undulation of BaF3-12 with 3.87 GPa applied (Figure 9A) was larger than that of BaF3-8 with 3.03 GPa applied (Figure 9B). From this, it was found that an increase in strain in BaF2 leads to a phase transition from a fluorite-type structure to a cotunnite-type structure.

[0085] Figure 10 shows the relationship between the load monitored by the pressure sensor and the generated pressure in Example 1. Figure 11 is a magnified view of region C in Figure 10.

[0086] Figures 10 and 11 show the pressure changes when the piezoelectric voltage is fixed at 980V and the gas pressure at 30Bar, and the first diamond anvil is rotated 180° at 2.60GPa, and then rotated another 180° (total 360°). According to Figures 10 and 11, the pressure change with rotation was slight (2.60GPa → 2.67GPa → 2.64GPa). The sample numbers for before rotation, 180° rotation, and 360° rotation were designated BaF2-5 to BaF2-7.

[0087] Figure 12 shows the uniaxial X-ray diffraction pattern in Example 1.

[0088] As shown in Figure 12, BaF2 (BaF2-5) before rotation had a fluorite-type structure, but BaF2 (BaF2-6) after 180° rotation had a completely cotunnite-type structure. Furthermore, the cotunnite-type structure was stabilized in BaF3 (BaF2-7) after 180° rotation.

[0089] Comparing Figure 8, which is from Reference Example 1 where rotational strain was not applied to the sample, with Figure 12, which is from Example 1 where rotational strain was applied to the sample, it was found that by applying rotational strain, a phase transition from a Fluorite-type structure to a Cotunnite-type structure can be induced at a lower pressure (in this case, only about 2.6 GPa).

[0090] Figure 13 shows the X-ray diffraction pattern in the radial direction in Example 1.

[0091] As shown in Figure 13, the undulation of BaF2-7 after 360° rotation (Figure 13A) was larger than that of BaF2-5 before rotation (Figure 13B). This indicates that the phase transition from the Fluorite-type structure to the Cotunnite-type structure proceeds as the strain in BaF2 increases, which is consistent with the result in Figure 9.

[0092] As explained above, the present invention has demonstrated that, by using the pressurizing and straining device, it is possible to apply rotational strain to a sample perpendicular to the uniaxial direction while applying ultra-high pressure in the uniaxial direction. Furthermore, it has been shown that by combining the pressurizing and straining device of the present invention with an X-ray diffractometer, it is possible to investigate the effect of strain under high pressure on the physical properties in both the uniaxial and radial directions. Because the pressurizing and straining device of the present invention is equipped with a control mechanism, it can automatically perform the process from pressurizing to the application of rotational strain. Needless to say, the pressurizing and straining device of the present invention can also be combined with optical microscopes and micro-Raman scattering measurement devices in addition to X-ray diffractometers to investigate various physical properties of the sample, such as observation, molecular structure, chemical bonding, and crystalline state. [Industrial applicability]

[0093] The pressurization and straining device of the present invention allows for the application of rotational strain to a high-pressure sample, forcibly applying differential stress at an arbitrary pressure, and then irradiating the sample with X-rays from both perpendicular and horizontal directions. The structure and stress state can then be observed using diffracted X-rays, including those in the radial direction. Since these operations can be performed remotely, measurements can be safely taken while irradiating with powerful X-rays inside a hatch at a synchrotron radiation facility or similar location. [Explanation of Symbols]

[0094] 11 cylinders 11X sample 11Y Gasket 11Z Set Screw 11Z Hex Socket Set Screw 100 Pressurization and Straining Device 110 Sample holding section 111 The First Diamond Anvil 112 The Second Diamond Anvil 113 First support 114 First support base 115 Pressure transmission section 116 Bearings 117 Rotating part 118 Second support 119 Second support base 120 rotation mechanism 121 Drive unit 122 Rotation axis 130 Actuator 131 Cylinder tube 132 Cylindrical connecting part 140 Pressing mechanism 150 Pressure Sensor 160 Control mechanism 210 Stepping Motor 220 Spur gear 230 Arm section 240 volts 250 Spur Gear Cover 300 Positioning mechanism 310 Lower Stage 320 Support legs with fine adjustment screws 32X Fine Adjustment Screw 330 backing plate 340 Direction change mechanism 410 Actuator drive circuit 420 Conversion Measurement Unit 430 Press-Drive Circuit 440 Central Processing Unit 450 Function Generator 460 RPM drive circuit 470 Pulse Generator

Claims

1. A sample holding section comprising first and second diamond anvils for holding a sample, wherein the first diamond anvil rotates, A rotating mechanism for rotating the first diamond anvil, Pressure is applied from the first diamond anvil side by an electrical signal, and the hollow actuator, A pressing mechanism that mechanically applies pressure from the second diamond anvil side, A pressure sensor for detecting the pressure applied to the sample held between the first and second diamond anvils, A control mechanism that controls the operation of the rotation mechanism, the actuator, and the pressing mechanism, and detects the operation of the pressure sensor. Equipped with, The aforementioned rotation mechanism comprises a drive unit and a hollow rotating shaft that is rotated by the drive unit. The aforementioned sample holding section is, A hollow first support base is connected to and fixes the first diamond anvil, A first support base that supports the first support base and is hollow, comprising: a pressure transmission part that receives pressure from the actuator and transmits it to the first diamond anvil; a rotating part that is joined to the first support base and rotates in engagement with the rotating shaft; and a bearing that resists the load received from the pressure transmission part and rotates the rotating part, A hollow second support base is connected to and fixes the second diamond anvil, A hollow second support base that supports the second support base, receives pressure from the pressing mechanism, and transmits it to the second diamond anvil, A cylinder and a second diamond anvil are provided to hold the first base, the first support base, the second base, and the second support base, while exposing the first and second diamond anvils. Equipped with, The rotating shaft is located within the actuator and engages with the rotating part of the first support base to rotate the first diamond anvil, thereby providing a pressurizing and straining device.

2. The pressurizing and straining device according to claim 1, wherein there is a step between the pressure transmission part and the rotating part, and the pressure transmission part is convex with respect to the rotating part.

3. The pressing mechanism is selected from the group consisting of a stepping motor, a hydraulic piston, and a gas pressure membrane, as described in claim 1.

4. The pressurizing and straining device according to claim 1, wherein the actuator is a stacked piezoelectric actuator.

5. The pressurizing and straining device according to claim 1, wherein the stroke of the actuator is in the range of 50 μm or more and 200 μm or less.

6. The pressurizing and straining device according to claim 1, wherein the pressure sensor is a quartz piezoelectric sensor.

7. The drive unit comprises a stepping motor that generates torque and an arm that transmits the torque to the rotating shaft by gears. The pressurizing and straining device according to claim 1, wherein the arm portion rotates with respect to the rotation axis.

8. The control mechanism is (A) The pressing mechanism applies pressure to the sample from the second diamond anvil side, (B) With pressure applied to the sample, the pressure sensor measures the pressure value from the actuator and adjusts the actuator to set the starting point of the actuator's pressure. (C) With pressure applied to the sample, the actuator, which has been adjusted to the pressure start point, continuously applies pressure from the first diamond anvil side. (D) With pressure applied to the sample, the rotating mechanism rotates the first diamond anvil. The pressurizing and straining device according to claim 1, wherein the operation of the rotating mechanism, the pressing mechanism, and the actuator is controlled and the operation of the pressure sensor is detected.

9. The system further includes a positioning mechanism for determining the position of the sample, The positioning mechanism is, Lower stage and A support leg connected to the first support base for adjusting the position of the sample, The backing plate that contacts the second support base and The pressurizing and straining device according to claim 1, comprising:

10. The pressurizing and straining device according to claim 9, further comprising a deflection mechanism connected to the lower stage and for changing the horizontal orientation of the pressurizing and straining device.

11. The pressure and strain device according to claim 10, wherein the deflection mechanism adjusts the horizontal and vertical positions of the sample.

12. The pressurizing and straining device according to claim 11, wherein the control mechanism further controls the operation of the steering mechanism.

13. The control mechanism is An actuator drive circuit that applies an electrical signal to the actuator, A conversion and measurement unit that converts and measures the pressure of the aforementioned pressure sensor, A pressing drive circuit that sends a drive signal to the pressing mechanism, A rotary drive circuit that sends a drive signal to the aforementioned rotary mechanism, The actuator drive circuit, the conversion measurement unit, the pressing drive circuit, and the central processing unit that controls the rotation drive circuit, The pressurizing and straining device according to claim 1, comprising:

14. The pressurizing and straining device according to claim 13, further comprising a pulse generator connected to the rotational drive circuit.

15. An X-ray diffractometer equipped with a pressurizing / straining device according to any one of claims 1 to 14.

16. A micro-Raman scattering measuring device equipped with a pressurizing / straining device according to any one of claims 1 to 14.

17. An optical microscope apparatus equipped with a pressurizing and straining device according to any one of claims 1 to 14.

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