Powder sample holder, method of manufacturing the same, and powder x-ray diffraction measurement method

Abstract

To provide a powder sample holder which prevents a powder sample from falling off therefrom and prevents a surface of the powder sample from loosing flatness when mounting the powder sample holder loaded with the powder sample on a measurement stage of a powder x-ray diffraction measurement device.SOLUTION: A powder sample holder having a recess to be filled with a powder sample under powder x-ray diffraction measurement is provided, the recess having an inverted truncated pyramid shape with a circular bottom, or an inverted truncated pyramid shape with a rectangular bottom, where the bottom and sides of the recess are textured.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a powder sample holder used in a powder X-ray diffraction measurement method, a method for producing the same, and a powder X-ray diffraction measurement method using the same. [Background technology]

[0002] In powder X-ray diffraction measurements, a sealed tube or rotating anticathode type X-ray tube is used as the X-ray source, and the crystalline state (composition, structure, etc.) of the compounds contained in the sample can be evaluated by using the pseudo-focusing method or the reflection method using a parallel beam system depending on the sample form, such as powder, lump, plate, or flake. In the pseudo-focusing method, the X-ray tube, the height position of the sample surface, and the detector that detects the X-rays diffracted by the sample are placed on a virtual circumference called the focusing circle. It is important to accurately position the height position of the sample surface on the focusing circle.

[0003] In response to the above-mentioned request, the applicant has disclosed in Patent Document 1 a sample holder consisting of a plate having a through hole, an organic film attached to one side of the plate with an adhesive so as to cover the through hole, and a thin collodion film attached to the inner surface of the organic film so as to fix a powder sample.

[0004] On the other hand, in powder X-ray diffraction measurement using the reflection method with the pseudo-focusing method, the powder sample is often filled into a powder sample holder, which is a flat molded body made of glass, aluminum, etc., and generally has a circular or rectangular recess with a depth of 0.2 to 0.5 mm formed in the center of the flat surface, for measurement. When the powder sample holder is made of glass, the bottom surface of the recess is roughly ground glass-like to prevent the filled powder from falling out.

[0005] When filling the concave portion of the powder sample holder with the powder sample, first fill the concave portion of the powder sample holder with the powder sample using a spatula or the like. Next, place the leveling member that comes with the powder sample holder on the surface of the powder sample. Then, slide the leveling member to press and fix the powder sample against the concave portion while leveling off the excess powder sample, so that the reference surface of the sample holder and the surface of the powder sample are flush with each other.

[0006] If the grinding operation of the powder sample is performed in only one direction with respect to the surface of the powder sample, the powder sample may have a preferred orientation, or the surface of the powder sample may be tilted rather than parallel to the reference surface of the powder sample holder. To avoid such a situation, when grinding the powder sample, hold the powder sample holder with your fingers and rotate the powder sample holder little by little to grind the powder sample. In other words, it is necessary to rotate the powder sample holder and repeat the grinding operation to randomize the direction in which the powder sample is ground.

[0007] When measuring the powder sample filled in the powder sample holder in this way, one method is to grasp the powder sample holder individually with fingers and place it on the measurement stage of the powder X-ray diffractometer, or to grasp the powder sample holder with an automatic transport robot and transport it to the measurement stage of the powder X-ray diffractometer and place it there. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2003-149174 A Summary of the Invention [Problem to be solved by the invention]

[0009] Whether the powder sample holders are individually grasped with fingers and placed on the measurement stage of the powder X-ray diffractometer, or the powder sample holders are grasped by an automatic transfer robot and transported to the measurement stage of the powder X-ray diffractometer for placement, vibrations and shocks are generated when the sample holder is placed on the stage.

[0010] As a result, if the powder sample has a low packing density, if the powder sample has good fluidity (the powder sample moves when the sample holder is tilted), or if the powder sample contains organic matter (polymeric substances, etc.) in addition to inorganic matter, the powder sample may fall off the powder sample holder or the flatness of the powder sample surface may be damaged. In such cases, it is necessary to repack the powder sample.

[0011] The present invention has been made under the above-mentioned circumstances, and the problem it aims to solve is to provide a powder sample holder that prevents the powder sample from falling off the powder sample holder and prevents the flatness of the powder sample surface from being damaged when the powder sample holder filled with the powder sample is placed on the measurement stage of a powder X-ray diffraction instrument, a method for manufacturing the powder sample holder, and a powder X-ray diffraction measurement method using the powder sample holder. [Means for solving the problem]

[0012] As a result of research conducted by the inventors to solve the above-mentioned problems, they found that when a powder sample holder filled with a powder sample is placed on the measurement stage of a powder X-ray diffraction instrument, if the powder sample has good fluidity as described above, it is not possible to prevent the powder sample from falling off the powder sample holder or to prevent the flatness of the powder sample surface from being damaged, even if the bottom surface of the recess in the sample holder is treated to have a frosted glass-like finish.

[0013] The inventors conducted further research and came up with the idea of ​​making the shape of the recess in an inverted truncated cone shape if the bottom surface of the recess in the sample holder is circular, and making the shape of the recess in an inverted truncated pyramid shape if the bottom surface of the recess is angular, and providing the bottom and side portions of the recess with an uneven surface finish, thereby completing the present invention.

[0014] That is, the first invention for solving the above-mentioned problems is: A powder sample holder having a recess for filling a powder sample to be measured by powder X-ray diffraction and a reference surface around the recess, The angle between the side surface of the recess and the reference surface is less than 90°, The powder sample holder is characterized in that the surface of the recess is roughened. The second invention is The powder sample holder according to the first invention is characterized in that the bottom surface of the recess is circular and the shape of the recess is an inverted truncated cone, or the bottom surface of the recess is angular and the shape of the recess is an inverted truncated pyramid. The third invention is The powder sample holder according to the first invention is characterized in that the recess is formed by a concave curved surface. The fourth invention is A powder sample holder according to any one of the first to third inventions, characterized in that the reference surface is provided with an uneven surface even in a portion that does not come into contact with a measurement stage of an apparatus used for powder X-ray diffraction measurement. The fifth invention is A method for manufacturing a powder sample holder according to any one of the first to third aspects of the present invention, This is a method for manufacturing a powder sample holder, characterized in that the uneven processing is performed by blast processing. The sixth invention is A powder X-ray diffraction measurement method characterized in that powder X-ray diffraction measurement is carried out using a powder sample holder according to any one of the first to third aspects of the present invention. Effect of the Invention

[0015] By using the powder sample holder of the present invention, when the powder sample holder filled with a powder sample is placed on the measurement stage of a powder X-ray diffraction instrument, the powder sample does not fall off the powder sample holder and the flatness of the powder sample surface is not compromised, thereby improving the workability of powder X-ray diffraction measurement. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic perspective view of a powder sample holder according to the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view of a powder sample holder according to the present invention. [Diagram 3]FIG. 2 is a schematic cross-sectional view showing the installation position of a protective material installed on the powder sample holder according to the present invention. [Figure 4] 5A to 5C are schematic cross-sectional views showing different installation positions of a protective material installed on a powder sample holder according to the present invention. [Diagram 5] FIG. 2 is a schematic perspective view of a mask material to be placed on the powder sample holder according to the present invention. [Figure 6] 6 is a schematic cross-sectional view taken along the line AA in FIG. 5, showing the positional relationship between the powder sample holder according to the present invention and a mask material to be placed on the powder sample holder. FIG. [Figure 7] 1A-1D are schematic cross-sectional views of powder sample holders having different configurations according to the present invention; [Figure 8] 5A to 5C are schematic cross-sectional views showing the installation positions of protective materials installed on powder sample holders having different shapes according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a first embodiment of a powder sample holder according to the present invention will be described with reference to FIG. 1 which is a schematic perspective view of the powder sample holder according to the present invention. In FIG. 1, a reference surface 13, which is the upper surface of a powder sample holder 11, is provided with a recess 12 in which a powder sample is filled. In FIG. 1, the powder sample holder 11 has a disk-shaped outer shape and the recess 12 is also round, but the shape is not particularly limited, and powder sample holders 11 having a flat plate shape and recesses 12 in which a powder sample is filled having a square shape are also generally available on the market. In addition, the powder sample holder 11 used for powder X-ray diffraction measurement can be made of glass, resin, or metal. The present invention can be applied to powder sample holders 11 having any shape and material.

[0018] In the present invention, a glass holder in which the powder sample holder 11 has a disk-shaped outer shape and the recess 12 is also round will be described as an example. The powder sample holder 11 has an outer periphery of 30 to 50 mmφ and a thickness of about 1 to 2 mm. The recess 12 has a size of 20 to 25 mmφ, a bottom surface 15 and a side surface 16, and a depth of about 0.2 to 0.5 mm.

[0019] 2 and 7 are schematic cross-sectional views of a powder sample holder according to the present invention. The powder sample holder 11 has a recess 12 in which a powder sample is filled. A reference surface 13, which is the upper surface of the powder sample holder other than the recess 12 and adjacent to the opening of the recess 12, serves as a reference surface for the height when filling the powder sample, and is machined with higher precision than the other surfaces. The holder also has an outer surface 14.

[0020] 2, recess 12 has an inverted truncated cone shape with the area of ​​the opening being larger than the area of ​​bottom surface 15, and side surface 16 is inclined with respect to bottom surface 15. It is preferable that the area of ​​the opening is 5 to 20% larger than the area of ​​bottom surface 15. When bottom surface 15 is a polygon such as a square, recess 12 has an inverted truncated pyramid shape (for example, when bottom surface 15 is a square, recess 12 has an inverted truncated quadrangular pyramid shape), but other points are similar to the case of having an inverted truncated cone shape.

[0021] By having the recess 12 in the shape of an inverted truncated cone or an inverted truncated pyramid, the contact area between the powder sample holder 11 and the powder sample is increased, and the physical adhesion force between the two is increased, thereby preventing the powder sample from falling off the powder sample holder or preventing the flatness of the powder sample surface from being damaged.

[0022] On the other hand, in FIG. 7, the recess 12 has a concave curved surface 17. As a result, if the opening of the sample holder 11 in FIG. 2 is made to have substantially the same area and depth, the contact area of ​​the powder sample holder 11 in FIG. 7 with the powder sample is larger than that of the inverted truncated cone or truncated pyramid shape described above, and the physical adhesive force between them is increased. This makes it possible to prevent the powder sample from falling off the powder sample holder and to prevent the flatness of the powder sample surface from being damaged. Furthermore, when the powder sample in the powder sample holder 11 is worn away, the change in the load applied to the powder sample becomes gentle, making it easier to align the surface of the sample powder with the reference surface 13.

[0023] Furthermore, since the recess 12 has a concave curved surface 17, there is no corner formed by the bottom surface 15 and the side surface 16 as in the case of the inverted truncated cone shape or inverted truncated pyramid shape shown in Figure 2, which is more preferable as it further increases the physical adhesion force between the powder sample holder 11 and the powder sample.

[0024] In addition, the angle θ between the side surface 16 of the recess shown in FIG. 2 and the reference surface 13, and the angle θ between the concave surface 17 shown in FIG. 7 and the reference surface 13 are preferably less than 90° and 80° or less and 1° or more. Here, the angle θ between the recess and the reference surface is the angle formed by the side surface 16 and the reference surface 13 in the cross-sectional view of the powder sample holder shown in FIG. 2 in which the recess is an inverted truncated cone or inverted truncated pyramid. In addition, in the cross-sectional view of the powder sample holder shown in FIG. 7 in which the recess has a concave surface, the angle θ is the angle formed by the tangent of the concave surface 17 at the intersection of the concave surface 17 and the reference surface 13 and the reference surface 13. In this case, θ is also preferably less than 90° and 80° or less and 1° or more.

[0025] There is no particular limitation on the method for manufacturing the powder sample holder 11 in which the recess 12 has an inverted truncated cone shape or an inverted truncated pyramid shape. However, the method for forming the recess 12 and forming an inclined surface on the side surface 16 of the recess 12 includes a machining method using a machining center. Specifically, a cylindrical or prismatic end mill is used as a grinding blade to perform pocket processing and groove processing, thereby forming a cylindrical or prismatic recess 12 on the reference surface 13 of the powder sample holder. Next, a tapered end mill is used to form an inclined surface on the side surface 16 of the recess 12. Alternatively, a cylindrical end mill may be used to incline the glass sample holder to form an inclined surface. The same applies when the powder sample holder 11 is made of resin or metal.

[0026] There is no particular restriction on the method for manufacturing the powder sample holder 11 in which the recess 12 has the concave curved surface 17, but it may be a machining method in a machining center. Specifically, an end mill having a ball-shaped (spherical) grinding blade may be used to form the recess 12 having the concave curved surface 17 on the reference surface 13 of the powder sample holder. The same applies when the powder sample holder 11 is made of resin or metal.

[0027] Moreover, this machining does not require high precision machining as is required for the reference surface 13. Therefore, for example, it is possible to use a tool such as a router bit used for precision engraving, dentistry, etc. to grind the side surface of the recess 12 of a powder sample holder having a recess with a normal cylindrical shape, prismatic shape, or concave curved shape, and machine the recess 12 into a predetermined inverted truncated cone shape, inverted truncated pyramid shape, or concave curved shape. The same applies when the powder sample holder 11 is made of resin or metal.

[0028] Furthermore, the bottom surface 15 and the inclined side surface 16 of the recess 12, and the surface of the concave curved surface 17 have fine irregularities. Because the bottom surface 15, side surface 16, and concave curved surface 17 of the recess 12 have finely uneven surfaces, the contact area between the powder sample holder 11 and the powder sample is further increased, increasing the physical adhesion force between the two, and the anchor effect between the two also prevents the powder sample from falling off the powder sample holder or the flatness of the powder sample surface from being damaged.

[0029] When performing X-ray diffraction measurement of a powder sample using the powder sample holder 11, in addition to the method of individually placing the powder sample holder 11 on the measurement stage of the X-ray diffraction instrument, the following method is generally adopted: the powder sample holder 11 is automatically transported to a sample holder mounting section of the measurement stage of the X-ray diffraction instrument which has a lifter mechanism.

[0030] In this case, the mounting part is lifted up by a lifter mechanism, and the reference surface 13 of the powder sample holder 11 is pressed against the sample height reference position (half height) of the measurement stage. In this method, it is sufficient that the portion where the sample height reference surface (half height) of the measurement stage and the reference surface 13 of the powder sample holder 11 come into contact is not machined to have an uneven surface. In other words, even if the periphery of the opening of the recess 12 in which the powder sample is filled in the powder sample holder 11 is machined to have an uneven surface, the periphery of the opening does not come into contact with the measurement stage, and so there is no problem with X-ray diffraction measurement.

[0031] (Method of machining recesses) Methods for creating fine irregularities on the bottom surface 15 and side surface 16 of the recess 12 and the concave curved surface 17 include processing with sandpaper and blasting, but blasting is preferred from the viewpoint of being able to process even fine parts such as the corners of the recess 12. During the blasting process, an abrasive is sprayed onto the powder sample holder 11 to create irregularities on the bottom surface 15 and side surface 16 of the recess 12, and the concave curved surface 17. Since the side surface 16 is inclined relative to the bottom surface 15, the abrasive is more likely to strike the bottom surface 15 during the blasting process, and a more uniform finely irregular surface can be formed than when the side surface 16 is perpendicular to the bottom surface 15. Even if the bottom surface 15 of the recess 12 is already roughly ground glass-like, the blasting process can be performed on top of it.

[0032] The surface roughness of bottom surface 15 and side surface 16 of recess 12 and concave curved surface 17 after the above-mentioned processing is preferably 1.0 to 6.0 μm in terms of Ra (arithmetic mean roughness). After processing, the surface roughness of the bottom surface 15 and side surface 16 of the recess 12 and the concave curved surface 17 is conveniently measured using a non-contact optical interference roughness meter that uses light instead of a contact stylus.

[0033] The surface roughness of the side surface 16 and the concave curved surface 17 of the recess 12 can be measured, for example, by preparing a powder sample holder 11 for checking the surface roughness in advance and cutting the powder sample holder 11 so that part of the side surface 16 and the concave curved surface 17 of the recess 12 can face directly upward. Then, the powder sample holder 11 is held so that part of the side surface 16 and the concave curved surface 17 of the recess 12 faces directly upward, and the surface roughness can be measured using an optical interference roughness meter.

[0034] When the abrasive is sprayed onto the powder sample holder 11, the surfaces other than the bottom surface 15 and side surface 16 of the recess 12 and the concave curved surface 17 are protected with a protective material, such as a seal or tape, or wax or brazing material, or a mask, to prevent uneven processing even when the abrasive hits them. After the blasting process is completed, the protective material is removed and the powder sample holder is then washed. The method of installing the protective material onto the powder sample holder 11 will be described with reference to Figures 3, 4, and 8.

[0035] Figures 3 and 8 are schematic cross-sectional views showing the installation positions of protective material 21 installed on powder sample holder 11 according to the present invention, and Figure 4 is a schematic cross-sectional view showing different installation positions of protective material 21 installed on powder sample holder 11 according to the present invention. In the powder sample holder 11, the protective material 21 is placed on the reference surface 13 or the outer surface 14 of the powder sample holder 11. For example, when a seal, tape, wax, brazing material, or the like is used as the protective material, the protective material 21 is attached or applied to the reference surface 13 and the outer surface 14.

[0036] Figures 3 and 8 show cases where protective material 21 is attached or applied to the entire surface of reference surface 13 and the entire surface of outer surface 14, while Figure 4 shows a case where protective material 21 is attached or applied to a portion of reference surface 13 and the entire surface of outer surface 14.

[0037] When the protective material 21 is applied to the entire surface of the reference surface 13, it is not necessary to cover the entire surface of the reference surface 13 except for the recess 12 (bottom surface 15, side surface 16, concave curved surface 17) with the protective material 21 as shown in Fig. 3. This is because, as described above, if the powder sample holder 11 is automatically transported to a sample holder mounting portion of a measurement stage of an X-ray diffraction apparatus having a lifter mechanism during X-ray diffraction measurement, even if the periphery of the opening of the recess 12 into which the powder sample of the powder sample holder 11 is filled is processed to be uneven, the periphery of the opening does not come into contact with the measurement stage, and so there is no problem with the X-ray diffraction measurement.

[0038] Furthermore, even when the powder sample holders 11 are individually placed on the measurement stage of the powder X-ray diffraction instrument, it is necessary to adjust the reference surface 13 to the half-cut position (the sample height which is half the direct beam intensity when measured without placing a sample on the measurement stage); however, it is sufficient if at least part of the reference surface 13 has a flat surface which can be used, for example, by using a dial gauge to adjust the powder sample holder 11 to the height of the half-cut position.

[0039] A convenient manufacturing method for forming fine irregularities on the bottom surface 15 and side surface 16 of the recesses 12 of a plurality of powder sample holders 11 will be described with reference to Figs.

[0040] Figure 5 is a schematic oblique view of a mask material 31 to be placed on the powder sample holder of the present invention, and Figure 6 is a schematic AA cross-sectional view of Figure 5 showing the positional relationship between the powder sample holder 11 of the present invention and the mask material 31 to be placed on the powder sample holder 11.

[0041] 5 and 6, a metal plate, a resin plate, or the like can be used as long as it can mask the other parts when forming fine irregularities on the bottom surface 15 and the side surface 16 of the recess 12 of the powder sample holder 11. However, a metal plate is preferable from the viewpoint of mechanical strength. For example, it is a metal plate having a thickness of 0.5 to 2.0 mm, and is provided with a plurality of openings 32. The openings 32 of the mask material 31 are the same as or larger than the openings of the recess 12 of the powder sample holder 11 described above, and have a smaller diameter than the reference surface 13.

[0042] When multiple powder sample holders 11 are blasted simultaneously, as shown in Fig. 6, the mask material 31 is placed on the reference surface 13 of the multiple powder sample holders 11, and the center of the opening 32 is aligned with the center of the opening of the recess 12. Then, the mask material 31 and the powder sample holder 11 are fixed to each other so that the mask material 31 does not move or separate from the reference surface 13 during the blasting process, but the fixing method is not particularly limited.

[0043] Then, with the mask material 31 and the multiple powder sample holders 11 fixed, an abrasive is sprayed onto the powder sample holder 11, thereby performing uneven processing on the bottom surface 15 and side surface 16 of the recess 12 of the powder sample holder 11, as well as the surrounding area of ​​the opening of the recess 12.

[0044] Incidentally, whether a protective material or a mask material is used, examples of the abrasive include silica sand, alumina, stone powder containing alumina, ceramic beads, glass beads, etc., and the abrasive may be selected according to the material of the powder sample holder 11. Depending on the spraying conditions of the abrasive (pressure, particle size and type of the abrasive), chipping or cracking may occur in the powder sample holder 11, or the abrasive may sink into the surface of the powder sample holder 11 and not be removed even by cleaning, resulting in the detection of a diffraction peak derived from the abrasive during X-ray diffraction measurement. Therefore, the spraying conditions of the abrasive may be considered and selected according to the material of the powder sample holder 11. [Explanation of symbols]

[0045] 11. Powder sample holder 12. Recess 13. Reference plane 14. External surface 15. Bottom 16. Side 17. Concave surface 21.Protective materials 31. Masking material 32. Opening

Claims

1. A powder sample holder having a recess for filling a powder sample to be measured by powder X-ray diffraction and a reference surface around the recess, The angle between the side surface of the recess and the reference surface is less than 90°, A powder sample holder characterized in that the surface of the recess is roughened.

2. 2. A powder sample holder as described in claim 1, characterized in that the bottom surface of the recess is circular and the shape of the recess is an inverted truncated cone, or the bottom surface of the recess is angular and the shape of the recess is an inverted truncated pyramid.

3. 2. A powder sample holder according to claim 1, wherein the recess is formed as a concave curved surface.

4. 4. A powder sample holder as described in any one of claims 1 to 3, characterized in that the reference surface is provided with unevenness even in a portion that does not come into contact with a measurement stage of an apparatus used for the powder X-ray diffraction measurement.

5. A method for manufacturing a powder sample holder according to any one of claims 1 to 3, comprising the steps of: A method for manufacturing a powder sample holder, comprising the steps of: forming the uneven surface by blasting;

6. 4. A powder X-ray diffraction measurement method, comprising carrying out powder X-ray diffraction measurement using the powder sample holder according to claim 1.

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