JPWO2007052688A1 - Method and apparatus for measuring orientation distribution of microcrystalline grains - Google Patents

Abstract

Provided is an orientation distribution measuring method and apparatus for inspecting the orientation distribution of fine crystal grains continuously supplied from a manufacturing process in-line or on-line. A predetermined angular width centered on a Bragg angle with respect to the surface of a measurement sample (microcrystal grains of a YBCO film (layer)) S formed into a monochromatic X-ray beam and grown on the metal tape MT The incident X-ray diffraction image is integrated by the two-dimensional X-ray detector 200 arranged in the diffraction direction to obtain a pole figure, and among the spread of the obtained pole figure in two directions, Using at least one (Δω direction) as an index, measurement of the orientation distribution of microcrystal grains in a continuously moving sample is performed inline or online.

Description

  The present invention relates to a crystal grain orientation distribution measuring method and apparatus for measuring the crystal grain orientation distribution of fine crystal grains such as a YBCO film (layer) used as a superconducting wire, for example. The present invention relates to a method and apparatus for measuring the orientation distribution of fine crystal grains, which can continuously measure the fine crystal grains grown on a metal tape in the manufacturing process of the wire.

  Superconductivity is an energy-saving technology that is applied to products typified by MRI and linear motor cars, for example, at present and in the future, because electric resistance is completely zero (0). Materials are being developed and studied. In addition, as a main application field, the superconducting material is mostly a coil device due to the above characteristics, and therefore, it is desired that the superconducting material is manufactured as a wire, that is, a superconducting wire. The following various manufacturing methods have already been proposed and put into practical use.

JP 2005-129529 A Satoshi Yamada “Manufacturing Process of Superconducting Wires Using Anisotropy” Material Integration Vol.18 No.2 (2005) An article published in a newspaper published on May 14, 2001 "High-performance superconducting wire has achieved 20 times the production speed-Demonstration with 10mY superconducting wire-" Fujikura Materials Technology Laboratory, Chubu Electric Power Co., Inc. Research Institute, Superconducting Engineering Laboratory, International Superconducting Industrial Technology Research Center An article published in a newspaper published on May 14, 2001 "High-temperature superconducting wire (YBCO) achieves world record-length x current value 8335Am (45.8m length and critical current value 182A)-a major record update-" , International Superconductivity Technology Research Center

  That is, in particular, according to Non-Patent Documents 1 to 3 described above, as a method for producing a Y-based superconducting wire, a YBCO layer is formed on a surface of a polycrystalline hastelloy metal tape via an oxide intermediate layer or the like by PLD. A method of manufacturing a superconducting wire by epitaxial growth using (Pulsed Laser Deposition) or the like is already known.

  At that time, the superconducting material grown on the surface of the metal tape can exhibit its performance only when the orientation of the crystal grains is aligned over the entire length. Therefore, in-line or on-line (in-line) measurement, especially in the manufacturing process, whether or not the high orientation state of the crystal grains of this superconducting material is maintained throughout the metal tape. It is strongly desired to do so.

  By the way, conventionally, the measurement of whether or not the grown microcrystal grains are in a highly oriented state is not limited to application to a superconducting material, but as an evaluation or analysis method thereof, for example, rocking curve measurement or This is generally realized by performing pole figure measurement. However, measurement by such an X-ray diffraction method usually involves cutting out a test piece from a measurement sample, and examining the cut-out measurement sample using, for example, a normal X-ray diffractometer installed in a laboratory. It was common to make measurements. That is, in the prior art, in-line or on-line inspection has not yet been realized for the measurement by the X-ray diffractometer in which the microcrystal grains grown on the surface of the tape are oriented, so that The actual situation is that the cut-out measurement sample is inspected and measured off-line, which is a destructive inspection.

  It is also conceivable to attach an X-ray diffractometer on the line by a conventional method. For example, it is a form such as a residual stress measuring device or an X-ray diffractometer for cultural properties, and these are structures in which an X-ray source, a goniometer, and a detector are integrated. It is also possible to attach to a part of the superconducting wire production line. However, in the X-ray diffraction apparatus described above, even if the apparatus is attached to a part of the production line, it is necessary to measure the X-ray diffraction intensity point by point while changing the angle. Therefore, there is a problem that it takes a long measurement time, which makes it difficult to put it into practical use as an in-line or online inspection method.

  Therefore, in the present invention, in view of the problems in the prior art described above, that is, including the superconducting material grown on the surface of the metal tape described above, the microcrystalline grains continuously supplied in the manufacturing process, It is an object of the present invention to provide a method capable of inspecting the orientation distribution of the grown microcrystal grains in-line or on-line, and an apparatus for realizing the method.

  In order to achieve the above-described object, according to the present invention, first, there is provided a method for measuring the orientation distribution of microcrystal grains in a measurement sample that is continuously moved. Is formed into an X-ray beam, and the formed X-ray beam is incident on the surface of the measurement sample with a predetermined angle width centered on a predetermined incident angle. The pole figure is obtained by integrating the diffraction image in the diffraction direction, and at least one of the spreads in the diffraction direction of the obtained pole figure is used as an index of the microcrystal grains in the measurement sample that is continuously moved. A method for measuring the orientation distribution of fine crystal grains for measuring the orientation distribution has been proposed.

  According to the present invention, in order to achieve the above-mentioned object, an X-ray generator that generates X-rays, and X-rays from the X-ray generator are monochromatized into a predetermined X-ray beam, In the crystal grain orientation distribution measuring apparatus comprising: an optical system incident on the surface of the measurement sample; and a two-dimensional X-ray detector that detects a diffracted X-ray of the X-ray beam incident from the optical system. The measurement sample is continuously moved, and the optical system makes the formed X-ray beam incident on the surface of the measurement sample with a predetermined angle width centered on a predetermined incident angle. The dimensional X-ray detector acquires the pole figure by integrating the X-ray diffraction image incident at the predetermined angle width, and indicates at least one of the spread in the diffraction direction of the obtained pole figure. As a microcrystal in the measurement sample that is continuously moved Orientation distribution measuring apparatus of the fine crystal grains provided with means for performing azimuth measurement is provided.

  In the present invention, in the above-described microcrystal grain orientation distribution measurement method or orientation distribution measurement apparatus, the optical system has a predetermined tilt angle of the X-ray beam in a range of 0 ° to 90 °. Or a means for making the X-ray beam incident on the surface of the measurement sample with the predetermined angular width by moving the X-ray beam around the predetermined incident angle. Preferably, the incident means includes a swing mechanism, or the X-ray beam is incident on the surface of the measurement sample with the predetermined angular width by using X-rays having a predetermined divergence angle. Means to do this may be provided. In that case, the incident means may be constituted by, for example, a curved crystal monochromator, or the X-ray generator is provided with a linear X-ray source, and the incident means has a predetermined divergence angle. X-rays may be formed.

  Further, according to the present invention, the orientation distribution measurement method for fine crystal grains or the orientation distribution measurement device described above is arranged in a plurality of channels with respect to the measurement sample that is continuously moved. Is also possible. As shown in the following embodiments, for example, it is possible to obtain a pole figure with two channels using 00l reflection and hkl reflection. Further, the orientation distribution measuring method for fine crystal grains or the orientation distribution measuring apparatus described above is preferably used for measuring the orientation distribution of the microcrystalline grains grown on the surface of the tape-shaped member. In particular, it is preferable to use it for on-line or in-line measurement of orientation distribution of fine crystal grains of YBCO which is a superconducting wire.

  As described above, according to the method of measuring the orientation distribution of microcrystalline grains or the orientation distribution measuring apparatus according to the present invention, it is possible to measure the orientation distribution of microcrystalline grains, which takes time in the conventional method, in a short time. By making it feasible, for example, in-line or on-line measurement of orientation distribution of fine crystal grains continuously supplied in the manufacturing process, including the superconducting material grown on the surface of the metal tape described above. Exhibits an excellent effect that can be realized.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Details of an orientation distribution measuring method and apparatus therefor according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

First, the principle of the orientation distribution measuring method for fine crystal grains according to the present invention, that is, the orientation state of crystal grains will be described. The attached FIG. 1A is a drawing of Ewald showing diffraction conditions. In the figure, A is the center of the Ewald sphere, and O is the origin of the reciprocal lattice. In addition, the vector k ₀ in the figure represents an incident X-ray, the vector k represents a diffracted X-ray, and the vector V represents a reciprocal lattice vector having a length of 1 / d (see FIG. 1B). Here, d is the surface interval of the noted lattice plane. Point A is the sample position in real space and can be rotated around the ω axis. When the ω axis is rotated, in the reciprocal lattice space, the pole sphere rotates around an axis parallel to the ω axis around its origin O (indicated by 1 / d sphere).

Here, consider the case where the sample is a single crystal. When the orientation of the crystal of the sample is adjusted and the reciprocal lattice point indicated by the symbol R is in contact with the Ewald sphere and the condition of k−k ₀ = V is satisfied as shown in FIG. . Therefore, when an X-ray film is placed in the direction of the diffraction angle 2θ and a photograph is taken, a diffraction spot corresponding to the reciprocal lattice point is photographed (see FIG. 1A). Note that the position of the diffraction spot at this time is indicated by a symbol DS in the figure.

  On the other hand, when the sample is a non-oriented polycrystal, the orientation of the crystal grains is randomly distributed. Accordingly, the reciprocal lattice points of each crystal grain are uniformly distributed on the pole sphere having the radius 1 / d. In such a state, the diffraction condition is satisfied at the portion where the Ewald sphere and the pole sphere intersect (the portion indicated by the dotted line MR in the figure), so that the half apex angle is 2θ from the sample position A in real space. A diffraction line is generated along the generatrix of the cone. That is, if a photograph is taken in the same manner as described above, a so-called Debye ring DR is photographed.

  By the way, the X-ray intensity along the Debye ring shows a uniform intensity distribution when the sample is not oriented. However, if the orientation distribution of crystal grains of the sample is biased, this Debye ring The X-ray intensity along the line is not uniform and has an intensity distribution. In addition, the state where the orientation distribution of crystal grains is biased in this way is said to have an orientation, to have a preferred orientation, or to have a texture. To do.

  Next, attached FIG. 2 is a schematic diagram showing a highly oriented state of the crystal grains in question here. This state can be interpreted as the spread of the reciprocal lattice point R in the case of the single crystal shown in FIGS. 1 (a) and 1 (b). The actual situation is almost the same in orientation, however, however, it is an aggregate of fine crystal grains having a slight orientation distribution. Therefore, such a reciprocal lattice point has a predetermined orientation as indicated by R ′ in the figure. With expanse. As described above, the fine crystal grains of the YBCO film grown on the surface of the metal tape are in the state shown in FIG. The shape of the diffracted X-ray obtained at this time is a linear image (thick portion in the figure) L having a different thickness at a part of the Debye ring DR. This is because the region where the diffraction line is generated is a portion where the Ewald sphere and the spread of the reciprocal lattice point coincide.

  Further, when the sample is rotated by ω (FIG. 1 (a)), the pole sphere is also rotated (rolled) around the point O. As shown in FIGS. 3 (a) to 3 (c), Ewald The part where the sphere and the spread of the reciprocal lattice point coincide also changes. That is, the portion where the Ewald sphere coincides with the spread reciprocal lattice point is changed by the ω rotation, and accordingly, the obtained diffraction line image (the thick Debyeing portion L) is also changed.

  On the other hand, as fine crystal grains S whose orientation state is measured by the above-described orientation measuring method, for example, the crystal lattice and the orientation state of YBCO which is a super electric wire are shown in FIG. The crystal system of this YBCO film (layer) is a so-called orthorhombic crystal, but the lattice constants of the two axes are very close to each other, so that it can be approximated by a tetragonal crystal. The lattice constants of the a and b axes at that time are 3.8 to 3.9 angstroms, and the c axis is about 11.7 angstroms. FIG. 4 shows only one crystal grain on the metal tape, and the a-axis or b-axis of the crystal grain is oriented parallel to the longitudinal direction or the width direction of the metal tape. In addition, the c-axis coincides with the normal direction of the surface of the metal tape. That is, the super electric wire whose orientation state is measured has a structure in which fine crystal grains having such an orientation are gathered.

  Next, the detailed configuration of the crystal grain orientation distribution measuring apparatus according to the present invention for measuring the orientation state by the orientation distribution measuring method will be described with reference to FIGS. In this figure, the symbol S is, for example, microcrystalline grains continuously supplied at a speed of about 1 m / hour, for example, super electric wire material. In the film forming process such as PLD (not shown), polycrystalline hastelloy metal The YBCO layer is epitaxially grown on the surface of the tape MT (in this example, the upper surface) via an oxide intermediate layer.

  In this azimuth distribution measuring apparatus, first, as shown in the attached FIG. 6A, a Y-direction moving mechanism 51 that can move in the Y-direction in the figure is mounted on a base 50. Further, on the Y-direction moving mechanism 51, a chi-angle tilting mechanism 52 having a substantially “C” -shaped outer shape is provided. The measurement sample S, which is fine crystal grains formed on the surface of the metal tape MT, is carried from a supply reel (not shown) at a substantially central portion of the χ angle tilting mechanism 52 having a substantially “C” -shaped outer shape. The sample is also carried out to a supply reel (not shown) via a pair of rollers 53 and 53 (that is, supplied in the X direction in the figure), and a sample stage 54 is provided between the rollers 53 and 53. ing.

  Further, above the substantially “C” -shaped chi-angle tilting mechanism 52, a substantially “C” -shaped outer shape is formed via a holding portion (support) 55 having an approximately “L” -shaped outer shape. A semicircular arc stage (circular stage) 56 is provided, and an X-ray generator 100 and a two-dimensional X-ray detector 200 described below can be freely set on the circular stage 56, respectively. It is attached as possible. Thereby, in this apparatus, it is possible to freely set the inclination angle χ within a wide range of 0 ° to 90 °. Note that reference numeral 140 in the drawing indicates a drive mechanism for swinging (swinging) the X-ray generator 100, which will be described later.

  Also, attached FIG. 6 (b) shows an example of the χ angle rotation setting by the χ (tilt) angle tilt mechanism 52 of the azimuth distribution measuring device. As is clear from this figure, this χ angle tilt is also shown. The mechanism 52 allows the X-ray generator 100 (including the two-dimensional X-ray detector 200) to be desired in a plane (YZ plane) perpendicular to the traveling direction of the sample S (X axis in the figure). The angle (posture) can be set.

  In the above azimuth distribution measuring device, as is apparent from the attached FIG. 5 or FIG. 7, the surface of the super electric wire that is the measurement sample S continuously supplied as described above (in this example, the upper side An X-ray generator 100 is provided at a position facing the surface), and this X-ray generator 100 emits X-rays generated from a dotted X-ray source 110, for example, at a tip of φ0.1-0. The sample is collimated through a collimator 120 having a pinhole of about 5 mm, narrowed down and irradiated onto the surface of the measurement sample S. A Cu target or the like is used as this X-ray source. In this X-ray generator 100, a Kβ cut filter 130 is disposed at the X-ray exit, and pseudo X-rays irradiated to the sample are monochromatically converted into Kα rays, that is, characteristic X-rays (specific X-rays). Constitutes the source of

  The X-ray generator 100 is mounted so as to be able to swing (swing) by a so-called swing mechanism 140 (that is, as shown in the drawing, the X-ray irradiation position on the surface of the sample S). Can be moved in the direction of rotation). More specifically, the swing mechanism 140 includes a rotating plate that sandwiches an arc-shaped worm wheel (not shown). The X-ray generator 100 and the collimator 120, which are the generation sources of the characteristic X-ray, It is fixed on the rotating plate. Although not shown in the drawing, a drive motor is attached to the rotating plate together with the worm shaft. The rotation of the worm shaft accompanying rotation of the drive motor causes θ (X-ray incident angle = Bragg angle). It is possible to scan continuously in the range of −Δω / 2 to + Δω / 2 (Δω: about several degrees) around the center (indicated by arrows in the figure).

  Then, the X-ray generator 100 rotates around its position, for example, around the rotation axis perpendicular to the paper surface with the X-ray irradiation point on the sample S as the center, as shown by the broken line in the figure. It can be rotated. In other words, the X-ray incident angle can be continuously scanned by Δω with the Bragg angle θ with respect to the target pole (reflecting surface) as the center. At this time, the X-ray shutter is opened at the scanning start time (θ−Δω / 2), and then the X-ray shutter is closed at the final time point (θ + Δω / 2) scanned by Δω.

  On the other hand, in the 2θ direction with respect to the direction of the average incident angle θ, for example, a two-dimensional X-ray detector 200 such as an X-ray cooled CCD is fixed and attached, and thus diffraction from the measurement sample S is performed. Wait for X-rays. That is, the high-sensitivity secondary detector 200 captures an image obtained by reflecting the characteristic X-rays emitted from the collimator 120 on the measurement surface of the sample S, that is, the normal to the measurement surface is Again, they are arranged so as to form an equal angle θ with respect to the measurement surface of the sample S.

  Reference numeral 90 in FIG. 5 denotes a control PC (CPU), and a part of the control PC (CPU) includes a storage device such as a hard disk drive. The storage device controls and measures each part of the apparatus. It is also possible to store various kinds of software for executing the above, or store the obtained image, measurement result, etc. in a part thereof. The control PC 90 also includes a display device 92 for displaying the reflected image obtained by the high-sensitivity secondary detector 200 to the operator, an input device such as a keyboard 93 and a mouse 94, and an unillustrated device. Is provided with an output device such as a printer. In addition, the control PC 90 also controls the rotation of the drive motor of the swing mechanism that scans the X-ray generator 100.

  FIG. 8 attached here shows an example of a specific configuration of the high-sensitivity secondary detector 200. That is, the detector 200 has, on its X-ray incident side, a scintillator 61 that emits light by incident X-rays, and an I.D. that multiplies a diffraction image obtained on the scintillator. I (image intensifier) 62 is provided. The light multiplied by I is incident and imaged on a two-dimensional (for example, a surface of about 20 mm × 20 mm) CCD device 64 by a coupling lens 63 disposed behind it, and converted into an electrical signal. . In FIG. 7, reference numeral 65 denotes the above I.D. 1 shows a power supply I, and is constituted by the control PC (CPU) 90 shown in FIG. Then, together with the CPU image capturing board 66, for example, using the control software stored in the storage device 91 of FIG. 5, the image formed on the CCD is captured and simultaneously displayed on the display device 92. Display the captured image.

  As described above, the two-dimensional X-ray detector 200 has position information of detected diffracted X-rays from a structure in which X-ray detection elements are arranged on a plane. Then, during the above period (that is, the period from the start point to the end point of the scan), the two-dimensional X-ray detector 200 captures (integrates) a diffracted X-ray image from the sample S. In addition, the image obtained by this becomes a pole figure.

  Next, the apparatus for actually measuring the crystal orientation of the YBCO film (layer) whose example is shown in FIG. 4 with the orientation measuring apparatus whose structure has been described above will be described more specifically. To do.

  As described above, the YBCO microcrystal that is the measurement sample shows a strong orientation in the c-axis. Therefore, 00l reflection is used for inspection of c-axis orientation by rocking curve measurement. In particular, since the 005 reflection, which is the fifth-order reflection, has a strong intensity, this is used. Specifically, the diffraction angle (2θ) is set to about 38.5 ° using CuKα rays. That is, the X-ray generator 100 is fixed at a position where the output X-ray is irradiated to the sample S at a Bragg angle (θ≈19.3 °), while the two-dimensional X-ray detector 200 is set at a diffraction angle. The position is fixed at (2θ≈38.5 °). Then, the X-ray generator 100 moves the ω angle back and forth within a range of ± several degrees (Δω / 2) around the Bragg angle θ, and the two-dimensional X-ray detector 200 generates diffracted X-rays. Measure strength. At this time, the X-ray generator 100 and the two-dimensional X-ray detector 200 are along the traveling direction (longitudinal direction: X axis) of the sample S that is continuously supplied, as shown in FIG. And on the equator plane ES perpendicular to the surface thereof.

  An example of a measurement result obtained on the two-dimensional X-ray detector 200 as described above (a photograph of an image obtained on the display device 92) is shown in FIG. 9A. That is, as is clear from this photograph, the YBCO microcrystal as the sample S has a azimuth distribution in the microcrystal grains, so that a pole figure having an image spread in the Δω and Δχ directions can be obtained. Here, the χ direction is a rotation direction around the X axis that is the traveling direction (longitudinal direction) of the sample S shown in FIG. The photographing was performed with the camera length Lc (distance between the sample and the film) set to 225 mm.

  On the other hand, for comparison, a reflection image (220 reflection image in this example) obtained by photographing a single crystal of Si as a sample S in the same manner as described above is a two-dimensional X as shown in FIG. The image obtained on the line detector 200 is a point-like image having no spread (the actual spread is only the spread due to the collimator size and the divergence angle).

  From the above results, according to the above-described orientation measuring method by arranging the above-described microcrystal grain orientation measuring device in the vicinity of the supply line of the metal tape MT, it is grown on the surface continuously. With respect to the sample S to be supplied, that is, the microcrystal of YBCO which is a super electric wire rod, the orientation state can be continuously measured in-line or on-line (In-line (on-line)).

As described above, the measurement image obtained on the two-dimensional X-ray detector 200 is a pole figure having image spread in the Δω and Δχ directions. As can be seen from the following calculation, the lateral spread (Δω) is the spread of ω (Δω), which is the scan angle of the incident X-ray.
Δω ＝ arctan （W / Lc） = arctan (6.33 / 225) ＝ 1.6 °… (1)

On the other hand, the relationship between the vertical spread V and Δχ, which is the spread of the χ angle, is a little complicated, but is obtained by the following equation.
Δχ = arccos (sinδ · sqrt (1/2 (1−cosδcos2θ))) (2)
Here, δ = arctan (V / Lc), Lc is the camera length, and 2θ is the diffraction angle. Further, sqrt in the formula is a symbol meaning a square root.

  Thus, only by scanning within a certain range in the ω angle direction, the spread in the ω axis rotation direction (Δω) and the spread in the χ axis rotation direction (Δχ) of the diffracted X-rays from the sample at once, Obtained as a pole figure, and by grasping the spread (Δω, Δχ) of the obtained diffraction image (pole figure) in the upper, lower, left, and right directions, the spread of reciprocal lattice points = orientation state = orientation distribution Can do. In other words, it becomes possible to observe in-line or on-line (in-line (on-line)) the orientation state of YBCO microcrystals, which are superelectric wire rods whose orientation state is desired to be observed. . The time for acquiring the above pole figure depends on the power of the X-ray source to be used and the sensitivity of the two-dimensional X-ray detector to be used, but it is about several seconds to several tens of seconds. It can be seen that the super electric wire continuously supplied at 1 m / hour is sufficient to measure this continuously.

  Moreover, when observing the orientation state of the super electric wire obtained on the metal tape from the measurement image obtained on the two-dimensional X-ray detector 200 as described above, An YBCO microcrystal in an orientation state acceptable for use as an electric wire is measured by the above method, or an allowable range of its spread is obtained in advance by calculation, and then the two-dimensional X-ray detector 200 is obtained. By comparing with the measurement image obtained above, it is possible to easily check whether it is necessary inline or online. In this case, the permissible range of spread obtained in advance is stored in, for example, the storage device 91 of FIG. 5, and is incident on the CCD device 64 and converted into an electrical signal. Based on the captured image, the control PC (CPU) 90 can make a comparative determination using software. And the result (for example, the content which warns that when a breadth exceeds a tolerance | permissible_range) can also be displayed on the said display apparatus 92 of FIG.

  Note that the above description only describes the procedure for monitoring the c-axis orientation (see FIG. 4 above) of the sample S to be measured. That is, in the YBCO microcrystal as a super electric wire, the a-axis or b-axis perpendicular to the c-axis is not necessarily aligned with the longitudinal direction or the width direction of the metal tape. Therefore, in order to confirm not only the c-axis orientation but also the a-axis or b-axis orientation, the pole figure may be measured using reflections other than the above-described 001, that is, hkl reflection.

  When examining at least one of the reflections other than 001 described above, for example, the 103 reflection may be taken as a diffraction vector. The 103 reflection has a diffraction angle (2θ) of 32.5 °, and the inclination from the c-axis (the rotation direction of the χ-axis) is 45.1 ° as shown in FIG. . Therefore, in this case, as shown in FIG. 10 attached, an equatorial plane ES in which the X-ray generator 100 and the two-dimensional X-ray detector 200 are arranged on the plane is represented by χ = 45 with respect to the Z axis in FIG. Set to 1 ° and measure the pole figure of 103 reflection in the same way as above.

  FIG. 11 is a diagram showing the measurement arrangement. That is, the X-ray incident angle and the outgoing angle are set to θ on the equator plane ES inclined by 45.1 °. Thereafter, the incident angle of the X-ray is continuously scanned by Δω with θ at the center in the equator plane. The X-ray shutter is opened at the start point of the scan, and after scanning by Δω, the X-ray shutter is closed. During this time, integration is performed by a two-dimensional detector (X-ray cooled CCD) 200 fixed in the direction of the emission angle θ. The obtained image is a 103 pole figure.

  In the above example, only the case where the traveling direction of the superconducting wire coincides with the X-axis direction has been described. However, as described above, in the case of YBCO microcrystals, equivalent reflection is also obtained in the four directions located every 90 ° around the Z axis in FIG. 11 because of the symmetry of the crystals. Therefore, the traveling direction of the superconducting wire can be set in the axial direction perpendicular to the X axis and the Z axis, that is, the Y axis direction. In the measurement arrangement shown in FIGS. 5 and 7 for monitoring the c-axis orientation, the equatorial plane ES has a degree of freedom of rotation about an axis (Z axis) perpendicular to the plane of the metal tape MT. That is, the equatorial plane ES on which the X-ray generator 100 and the two-dimensional X-ray detector 200 are arranged may be arranged at right angles to the longitudinal direction (X axis) of the tape or at an arbitrary angle. You may do it.

  In order to monitor the orientation state of the YBCO microcrystal grains that are super electric wires grown on the surface of the metal tape MT, as described above, in order to monitor the c-axis orientation, the fifth-order reflection is performed. The measurement arrangement of the apparatus for monitoring the 005 reflection (see FIG. 7 above: hereinafter referred to as the 005 channel) and 103 for monitoring the a- and b-axis orientations where equivalent reflection is obtained as described above. It is preferable to arrange an azimuth measuring device composed of the X-ray generator 100 and the two-dimensional X-ray detector 200 in two channels, the channel (see FIG. 11 above).

  However, since the above 103 pole figure includes the l component of hkl, not only the a-axis and b-axis orientations, but also the influence of the c-axis orientation actually appears. That is, if there are distributions in the orientations of the a, b, and c axes in the microcrystal grains, this 103 pole figure also spreads. Therefore, even if only one of the 103 channels is monitored, it is possible to monitor the orientation of each axis of the crystal grains. This is because, in particular, in YBCO microcrystal grains, although it is possible to generate an orientation distribution with the a-axis, b-axis, and c-axis as rotational axes, it is unlikely that an orientation distribution will occur with the diffraction vector 103 as the rotational axis. It is.

  Further, the 200 or 020 (200, 020) reflection of YBCO fine crystal grains, which are super electric wires grown on the surface of the metal tape MT, will be described. As shown in the attached FIG. 12, the 200,020 reflection is substantially parallel or orthogonal to the a-axis or b-axis, and the inclination from the c-axis (Z-axis) as shown in the attached FIG. (Rotation direction of χ axis) is approximately 90 °. Further, the d value which is a lattice constant is about 1.93 angstroms, and its Bragg angle (θ≈23.6 °) and diffraction angle (2θ≈47.2 °), X-ray generation The apparatus 100 is fixed at a position that satisfies these conditions. In this case, in this example, as shown in FIG. 15 attached, the inclination angle χ is about 89 ° so that the X-rays from the X-ray generator 100 are incident on the surface of the sample S. Preferably, it was set to 89.5 ° (that is, in this apparatus, the inclination angle χ can be set within a range of 0 ° to 90 °). As a result, a measurement result (a photograph of an image obtained on the display device 92) as shown in FIG. 13 was obtained on the two-dimensional X-ray detector 200.

  That is, also in this case, similarly to the above, the diffracted X-ray from the sample spreads in the ω-axis rotation direction (Δω only by scanning within a certain range in the ω angle direction (in this case, + Δω scan). ) And a spread in the χ axis rotation direction (in this case, Δχ / 2) is obtained as a pole figure, and a spread (Δω) in the vertical and horizontal directions of the obtained diffraction image (pole figure) is obtained. , Δχ / 2), the spread of reciprocal lattice points = the state of orientation = the orientation distribution can be grasped.

  Subsequently, a method obtained by further developing the above method will be described below. In this method, two reflections are caused simultaneously by scanning one incident X-ray beam. Each reflection is detected by a two-dimensional detector, so that pole figures of two poles are obtained simultaneously. In this method, two pole figures can be monitored simultaneously.

  In this arrangement, the diffraction X-ray may not come out to the upper hemisphere (that is, the Z component of the vector k in FIG. 1 is positive) unless the diffraction angle is high to some extent. By the way, YBCO fine crystal grains, which are super electric wires grown on the surface of the metal tape MT, can use 108 reflection whose diffraction angle is 68.7 ° and whose strength is somewhat high. That is, as shown in FIGS. 16 (a) and 16 (b), this 108 reflection is similar to the above-described 103 reflection in four places around the c-axis and reflections equivalent to rotational symmetry (108, 018, -108). , 0-18). The angle formed by this 108 reflection with the Z axis is about 20.8 °.

  Therefore, as shown in FIG. 17, the surface normal direction of the superconducting wire tape is made to coincide with the Z axis, and the longitudinal direction or the width direction is made to coincide with the X axis or the Y axis. When the incident X-ray is scanned by Δω in the XZ plane with the angle of ω from the X axis centered around 37.1 ° in the same manner as described above, reflection occurs in two diffraction vector directions 108. Occur. In this figure, 018 and 0-18 facing each other are shown. These are vectors extending on the XZ plane, and the angle formed with the Z axis is about 20.8 °. That is, these diffractions do not occur on the equator plane (XZ plane), but occur in the vertical direction of the equator plane. Therefore, the two-dimensional X-ray detectors 200 and 200 fixed in these directions respectively perform integral imaging of the diffraction line images. In this way, two pole figures, that is, pole figures of 018 and 0-18 in the above example, are obtained simultaneously by scanning one X-ray incident beam.

  Note that the direction of the diffraction lines can be obtained by calculation as follows. First, as one expression method, in the drawing of Ewald shown in FIG. 18, the direction of the diffraction line is along the generatrix of the 2θ cone, and it swings up and down from the equator plane by α angle = 25.5 °. As another expression, the direction of the diffraction line occurs in the direction of μ = 29.5 ° and ν = 23.6 ° as shown in FIG. Note that the angle μ is an angle formed by the projection line of the diffraction line onto the XY plane and the X axis, and the angle ν is an elevation angle of the diffraction line from the XY plane. Therefore, the two two-dimensional X-ray detectors 200 and 200 may be arranged in the mirror symmetry on the XZ plane in these directions.

  In the above-described embodiment, the X-ray generator 100 is swung using the swing mechanism 140 to swing the X-ray generated by the point X-ray source 110 with θ (X-ray Only the structure in which scanning is continuously performed in the range of −Δω / 2 to + Δω / 2 (Δω: several degrees) around the incident angle = Bragg angle) is described. However, the present invention is not limited to such a configuration.

  For example, as shown in attached FIG. 19, unlike the above configuration, the structure of an incident optical system using a curved crystal monochromator 105 is shown. In the incident optical system using this curved crystal monochromator, as is apparent from the figure, the surface of the X-ray having a predetermined divergence angle irradiated from the point-like X-ray source 110 of the X-ray generator 100 is applied to the surface. Irradiated onto the curved curved crystal monochromator 105, only the X-ray component of a predetermined wavelength is reflected and converged by the action of the curved surface. Therefore, in this incident optical system, a sample is placed at the convergence point of characteristic X-rays formed by the curved crystal monochromator 105. In the figure, reference numeral 106 denotes a width limiting slit for limiting the width (irradiation field) of characteristic X-rays.

  In other words, according to the incident optical system using the curved crystal monochromator, as is apparent from the above figure, the characteristic X-ray irradiated on the sample is always equivalent to swinging by the Δω angle. Therefore, unlike the above example, the swing operation of the incident optical system by the swing mechanism is not necessary, and is particularly suitable for shortening the measurement time. In this example, the X-ray source is about 0.1 mm, and the size of the convergence point is about the same. Further, the X-ray irradiation field on the sample is limited by using a width limiting slit 106 of about 0.1 to 0.2 mm. In addition, the curved crystal is made of, for example, α-Quartz, Ge, Si or the like. Further, according to such a curved crystal monochromator, a divergence angle up to about 4 ° can be manufactured. Alternatively, instead of the above, it is also conceivable to use a glass tapered capillary.

  Alternatively, as shown in FIG. 20, it is possible to obtain X-rays having a predetermined divergence angle by using an X-ray generation apparatus 100 provided with a linear X-ray source 110 '. For example, when a linear ordinary sealed X-ray tube is used, an apparent size of 0.04 mm × 12 mm is obtained with long fine focus, and a focus size of 0.2 mm × 12 mm is obtained with broad focus. By using these X-ray tubes, F = 12 mm can be obtained. In this case, the X-ray generator 100 is fixed so that the supplied sample S, that is, a microcrystal of YBCO, which is a super electric wire, is arranged at a position M from the X-ray source. At that time, for example, a knife edge 150 is arranged immediately above the sample surface. This is the same as the role of the pinhole slit in the collimator, and is for determining the X-ray irradiation width.

  The gap between the sample surface and the edge is, for example, about 0.1 mm to 0.5 mm. Furthermore, an X-ray introduction path 160 made of a conical metal cylinder is provided between the X-ray source and the sample. This forms a protective cylinder for preventing unnecessary X-rays from leaking outside as much as possible. Moreover, the exit narrowed in the sample direction of the conical cylinder is a so-called width limiting slit 161 for limiting the width of the irradiation X-ray. In this example, the width in the direction perpendicular to the paper surface of the drawing is limited to determine the height of X-ray irradiation. Specifically, like the gap between the knife edges 150, a gap of about 0.1 mm to 0.5 mm is provided. In such a state, when M = 150 mm is set, an angle of about 4.5 ° can be taken as the X-ray convergence angle Δω. In the above description, when the incident angle ω at the center of the incident X-ray is matched with the incident angle of the target reflection, a diffracted X-ray is generated, and a two-dimensional X-ray detector (not shown) fixed in the direction of the diffracted X-ray. Thus, a diffraction image is taken. Also in this case, as in the case of using the curved crystal monochromator, the swing of the ω angle is not necessary.

  In this way, instead of the structure in which the irradiated X-ray is continuously scanned in the predetermined range around the Bragg angle by moving the X-ray source, the X-ray having the convergence angle Δω can be used instead. As described above, a pole figure is obtained by integral imaging on the two-dimensional X-ray detector 200. Then, by observing the spread of the image in the Δω and Δχ directions from the obtained pole figure (for example, the image obtained on the monitor), the orientation state of the YBCO microcrystal which is a super electric wire rod Can be measured continuously inline or online (in-line (on-line)). That is, X-rays having a convergence angle Δω are incident on the measurement surface of the sample S at a predetermined angle θ, and the reflected (diffracted) X-rays are integrated and photographed on the two-dimensional X-ray detector 200, thereby diffracted X-rays. The spread in the ω-axis rotation direction (Δω) and the spread in the χ-axis rotation direction (Δχ) are obtained as a pole figure all at once. Then, by examining the vertical spread (Δω, Δχ) of the obtained diffraction image (pole diagram), it is possible to grasp the spread of the reciprocal lattice point = the state of orientation = the orientation distribution. In other words, the orientation state of the YBCO microcrystal that is a super electric wire can be observed inline or online (In-line (on-line)).

  In the above description, from the structure of the azimuth measuring apparatus described above, particularly the structure of the X-ray generation source, it is grown on the metal tape MT and continuously supplied while moving in the longitudinal direction. A two-dimensional X-ray detector 200 receives diffracted X-rays generated by irradiating only a part (for example, the center) of a sample S, which is a YBCO microcrystal having a width of several mm, with X-rays. The change in the spread of the pole figure obtained as a result is monitored. However, the orientation state of the YBCO microcrystals grown on the metal tape MT is measured and monitored not only in a part in the width direction but also in a plurality of points in the width direction for the sample S. Can be considered. In such a case, for example, so-called mapping may be considered while moving the X-ray irradiation field in the width direction. However, in that case, an apparatus configuration provided with a parallel movement mechanism in the sample width direction of the measurement system is required, and the mechanism becomes complicated and difficult to realize.

  Therefore, another embodiment that makes it possible to monitor the sample in the width direction at once without a parallel movement mechanism in the width direction of the sample to be measured will be described below. That is, as shown in FIG. 21, for example, instead of one pinhole attached to the tip of the collimator 120 shown in FIG. 5, a collimator provided with a slit having a narrow gap or a plurality of pinholes arranged. Is used. That is, the width of the ω scan direction is kept narrow and the width is increased so that X-rays are irradiated over the entire width direction of the sample S or a desired range. In the example shown in the figure, the exit width limiting slit of the X-ray path (the slit of the narrow gap at the tip of the collimator) is formed so as to extend in the direction perpendicular to the paper surface of the figure, and the X-ray is applied to the entire region in the width direction of the sample S. Is irradiated. Reference numeral 210 in the drawing is a light receiving surface of the two-dimensional X-ray detector 200.

  An example of an X-ray image observed by the structure of the azimuth measuring apparatus according to another embodiment described above is shown in FIG. That is, on the light receiving surface 210 of the two-dimensional X-ray detector 200, an image is obtained in which the pole figure shown in FIG. 8 is continuously or superimposed in a plurality of Δχ directions (see FIG. 22A). reference). In this case, the spread of the width in the Δχ direction cannot be observed. However, since the information (width spread) in the Δω direction is stored, the orientation state of the YBCO microcrystal is monitored by the width of the Δω. It is possible. For example, as shown in FIG. 22 (b), a plurality of detection lines (broken lines in the figure) are set, a rocking curve on the detection lines is obtained, and whether or not the half width exceeds a preset threshold value. It is possible to determine the quality of the orientation state of the YBCO microcrystals grown on the metal tape MT.

  Or, although not shown, by using a collimator in which a plurality of pinholes are arranged, and setting the distance between these pinholes to a value that takes into account the width of the pole figure that is spread by the orientation distribution of the fine crystal grains, It is also possible to obtain an image having information (width expansion) in the Δχ direction and Δω direction in the entire width direction of the sample S.

  As described in detail above, according to the method and apparatus for measuring the orientation distribution of microcrystalline grains of the invention, it is possible to perform the orientation measurement of microcrystalline grains that takes time in the conventional method in a short time. For example, it is possible to realize in-line or on-line orientation measurement of fine crystal grains that are continuously supplied in the manufacturing process, including the superconducting material grown on the surface of the metal tape described above. It became.

It is a drawing of Ewald for explaining the diffraction conditions for realizing the orientation distribution measurement of the microcrystal grains of the present invention, and a partially enlarged view thereof. It is a figure explaining the state of the reciprocal lattice point by the aggregate of the microcrystal grain on an Ewald sphere. It is a figure which shows the change of the expansion of an Ewald sphere and a reciprocal lattice point when the sample rotates ω. It is a figure which shows the crystal lattice of the fine crystal grain by which orientation condition is measured by the orientation distribution measuring method of this invention, ie, the crystal lattice of YBCO which is a super electric wire, and its orientation condition. It is a block diagram which shows the schematic structure about the orientation distribution measuring apparatus for implementing the said orientation distribution measuring method. It is a figure which shows an example of the detailed structure of the said orientation distribution measuring apparatus, and its chi rotation setting. It is a perspective view which shows an example of arrangement | positioning with respect to the sample of the said X-ray generator and a secondary detector especially about the said orientation distribution measuring apparatus. It is a figure which shows an example of the specific structure of the secondary detector in the said orientation distribution measuring apparatus. It is a figure which shows the image obtained by the Si single crystal for a comparison with the image by the microcrystal grain with an orientation distribution obtained by the two-dimensional X-ray detector in the said orientation distribution measuring apparatus. It is a figure including a stereo projection figure for demonstrating arrangement | positioning of 103 reflection of YBCO detected by the said azimuth | direction measuring apparatus. It is a figure which shows arrangement | positioning in the orientation distribution measuring apparatus for measuring the pole figure by said 103 reflection. It is a figure including a stereo projection figure for demonstrating arrangement | positioning of 200,020 reflection of YBCO detected by the said orientation measuring apparatus. It is a figure which shows the image by the microcrystal grain with the orientation distribution of 200,020 reflection obtained by the said two-dimensional X-ray detector. It is a figure which shows arrangement | positioning in the azimuth | direction distribution measuring apparatus for measuring the pole figure by the said 200,020 reflection. It is a figure explaining the incident angle to the microcrystal grain with the orientation distribution of the said 200,020 reflection. It is a figure including a stereo projection figure for demonstrating arrangement | positioning of 108 reflection of YBCO detected by the said orientation distribution measuring apparatus. It is a figure which shows arrangement | positioning in the azimuth | direction measuring apparatus for measuring the pole figure by said 108 reflection. It is explanatory drawing by drawing of Ewald which is one expression which shows the direction of the diffraction line of said 108 reflection. It is a figure which replaces with the X-ray generator provided with the swing mechanism in the said orientation distribution measuring apparatus, and shows the structure of the incident optical system using the curved crystal monochromator. It is a figure which shows the structure of using the X-ray generator provided with the linear X-ray source instead of the X-ray generator provided with the swing mechanism in the said orientation distribution measuring apparatus. It is a figure which shows an example of the azimuth | direction distribution measuring apparatus for measuring and monitoring the state of orientation of a YBCO microcrystal at several points of the width direction of a sample. It is a figure which shows an example of the image observed with the azimuth | direction distribution measuring apparatus of the said FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... X-ray generator 110 ... X-ray source 120 ... Collimator 130 ... K (beta) cut filter 140 ... Swing mechanism 200 ... Two-dimensional X-ray detector 210 ... Light-receiving surface of a two-dimensional X-ray detector MT ... Metal tape S ... Measurement sample (Microcrystal grains of YBCO film (layer))

Claims (17)

  A method for measuring the orientation distribution of microcrystal grains in a measurement sample that is continuously moved, wherein the monochromatic X-ray is formed into an X-ray beam, and the formed X-ray beam is converted into an X-ray beam. Incident to the surface of the measurement sample with a predetermined angle width centered on a predetermined incident angle, and an X-ray diffraction image incident at the predetermined angle width is integrated in the diffraction direction to obtain a pole figure. The orientation of the microcrystalline grains is measured by measuring the orientation distribution of the microcrystalline grains in the measurement sample that is continuously moved, using at least one of the spread in the diffraction direction of the obtained pole figure as an index. Distribution measurement method.   2. The azimuth distribution measuring method according to claim 1, wherein a predetermined inclination angle of the X-ray beam can be set in a range of 0 ° to 90 °, and is incident on the surface of the measurement sample with the predetermined angle width. A method for measuring the orientation distribution of fine crystal grains.   2. The azimuth distribution measuring method according to claim 1, wherein the X-ray beam is incident on the surface of the measurement sample with the predetermined angle width by moving the X-ray beam around the predetermined incident angle. A method for measuring the orientation distribution of microcrystalline grains.   2. The azimuth distribution measuring method according to claim 1, wherein the X-ray beam is incident on the surface of the measurement sample with the predetermined angular width by using X-rays having a predetermined divergence angle. A method for measuring the orientation distribution of microcrystalline grains.   The orientation distribution measurement method according to claim 1 is performed in a plurality of channels with respect to the moving direction of the measurement sample that is continuously moved, thereby measuring the orientation distribution of the microcrystal grains in the measurement sample. A method for measuring the orientation distribution of fine crystal grains.   The orientation of the microcrystalline grains, wherein the measurement sample for measuring the orientation distribution of the microcrystalline grains by the orientation distribution measuring method according to claim 1 is microcrystalline grains grown on the surface of the tape-shaped member. Distribution measurement method.   6. A method for measuring orientation distribution of microcrystalline grains, wherein the measurement sample for measuring orientation distribution of microcrystalline grains by the orientation distribution measuring method according to claim 5 is a microcrystalline grain of YBCO which is a superconducting wire.   An X-ray generator that generates X-rays, an X-ray generated from the X-ray generator is monochromatized to form a predetermined X-ray beam, and is incident on the surface of the measurement sample. In a microcrystal grain orientation distribution measuring apparatus including a two-dimensional X-ray detector for detecting diffracted X-rays of an incident X-ray beam, the measurement sample is continuously moved, and the optical system is formed as described above. The X-ray beam is incident on the surface of the measurement sample with a predetermined angular width centered on a predetermined incident angle, and the two-dimensional X-ray detector further receives the X-ray incident with the predetermined angular width. Measure the orientation of microcrystal grains in the measurement sample that is continuously moved, using at least one of the spreads in the diffraction direction of the obtained pole figure as an index. Microcrystal characterized by having means for performing Orientation distribution measurement device.   9. The azimuth distribution measuring apparatus according to claim 8, wherein a predetermined inclination angle of the X-ray beam can be set in a range of 0 ° to 90 °, and is incident on the surface of the measurement sample with the predetermined angle width. An apparatus for measuring the orientation distribution of microcrystalline grains.   9. The azimuth distribution measuring apparatus according to claim 8, wherein the optical system moves the X-ray beam around the predetermined incident angle so as to have a predetermined angular width with respect to the surface of the measurement sample. An apparatus for measuring orientation distribution of fine crystal grains, characterized by comprising means for making an incident.   10. The orientation distribution measuring apparatus according to claim 9, wherein the incident means includes a swing mechanism.   9. The azimuth distribution measuring apparatus according to claim 8, wherein the optical system uses the X-ray beam with X-rays having a predetermined divergence angle, so that the predetermined angular width with respect to the surface of the measurement sample is obtained. An apparatus for measuring orientation distribution of fine crystal grains, characterized by comprising means for making an incident.   13. The orientation distribution measuring apparatus according to claim 12, wherein the incident means includes a curved crystal monochromator.   13. The orientation distribution measuring apparatus according to claim 12, wherein the X-ray generator includes a linear X-ray source, and the incident means forms X-rays having a predetermined divergence angle. Crystal grain orientation distribution measuring device.   An orientation distribution measuring apparatus for microcrystal grains, wherein the orientation distribution measuring apparatus according to claim 8 is arranged in a plurality of channels with respect to the measurement sample that is continuously moved.   The orientation of the microcrystalline grains, wherein the measurement sample for measuring the orientation distribution of the microcrystalline grains by the orientation distribution measuring apparatus according to claim 8 is microcrystalline grains grown on the surface of the tape-shaped member. Distribution measuring device.   9. The crystal grain orientation distribution measuring apparatus according to claim 8, wherein the measurement sample for measuring the orientation distribution of the microcrystal grains by the orientation distribution measuring apparatus according to claim 8 is a microcrystal grain of YBCO which is a superconducting wire.

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