JP2015045502A - X-ray stress measurement tool, and x-ray diffraction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray stress measurement tool capable of measuring a stress by irradiating a test piece over a wide angle with X rays, and to provide an X-ray diffraction device.SOLUTION: An X-ray stress measurement jig has paired test piece-holding stages 3 which are disposed on a rectangular plate 1 and apply a bend stress or a tensile stress to a test piece S by increase or decrease in space between the test piece-holding stages 3. At least one of the paired test piece-holding stages 3 is movable in the horizontal direction, and stress application members 7 for applying a stress to the test piece S are stood above the paired test piece-holding stages 3 to deform the test piece S in the horizontal direction, and a height of the stress application members 7 are equal to or less than that of the test piece S. The X-ray diffraction device is loaded with the X-ray stress measurement tool.

Description

  The present invention irradiates the surface of the test piece placed on the test piece holding stage with X-rays from various angles to detect changes in the stress of the test piece under load and to measure the X-ray stress constant. The present invention relates to an X-ray stress measurement jig for performing the above and an X-ray diffractometer equipped with the jig.

The sin ² ψ method has been widely used as a method for measuring residual stress by X-ray, but this method assumes a plane stress in principle, so that the stress component in the depth direction cannot be measured. there were. Around 2008, a two-dimensional (2D) method was developed to detect diffracted X-rays with a two-dimensional detector and detect stress in the depth direction from changes in the Debye ring. The tensor can be measured.

  When the test piece is unstrained, the Debye ring is circular, but if there is residual stress, distortion occurs and becomes elliptical. The 2D method is a stress measurement and analysis method that calculates the total stress component from a part of this Debye ring deformation, and can measure the entire Debye ring instead of a point with a highly sensitive two-dimensional detector. There is an advantage that even a test piece having a low diffraction intensity, a coarse grain test piece, a strongly oriented test piece, and a test piece in a triaxial stress state, which were impossible, can be obtained quickly and accurately.

  As an improvement of the X-ray stress measurement jig, there is one described in Patent Document 1. As shown in FIG. 3 of the specification, this is a stress holding device (X-ray stress measuring jig) mounted on the X-ray diffraction apparatus, and has the structure shown in FIG. It is. This has a mechanism in which at least a pair of wedges 13 and 14 are installed, and the load direction is changed by each wedge 13 and 14. However, as shown in FIG. 2, in this stress holding device, a pair of load acting pins (upper) 11 and a pair of load acting pins (lower) 16 are parallel to the horizontal plate surface of the rectangular plate 21. Since the bending load is applied in the vertical direction of the intermediate member 24 (test piece holding stage), the distal ends of the left and right beams 23 become obstructive, and the X-ray incidence range is limited to 158 ° or less. There is a drawback that it will be.

  As shown in FIG. 8, in the 2D method, the test piece holding stage on which the test piece is placed is tilted by 0 to 90 ° (that is, the tilt angle ψ = 0 to 90 ° with respect to the vertical axis). ) The test piece holding stage is rotated horizontally by 0 to 360 ° (that is, at a rotation angle φ = 0 to 360 ° with respect to the vertical axis), and the test piece is irradiated with X-rays. However, if the beam 23 as described above is present on the test piece holding stage, for example, as shown in FIG. 9, the beam 23 becomes an obstacle, and the X-rays irradiated on the test piece cannot reach the detector. . Further, the beam 23 may get in the way and the X-ray may not hit the test piece. Therefore, there is a problem that stress by the 2D method cannot be measured over a wide tilt angle ψ and rotation angle φ.

JP 2009-008665 A

  In the present invention, X-ray stress can be detected by irradiating X-rays over a wide range of tilt angles and rotation angles without hindering the incidence of X-rays on a member such as a beam that applies stress to the test piece. It is an object of the present invention to provide a measuring jig and an X-ray diffractometer equipped with the X-ray stress measuring jig.

The X-ray stress measurement jig according to the present invention, which has been made to solve the above problems, has a pair of test piece holding stages disposed on a rectangular plate, and approaches or separates the test piece holding stage. An X-ray stress measurement jig for applying stress to the test piece by
At least one of the pair of test piece holding stages can be moved in the horizontal direction, and a stress loading member for applying stress to the test piece is provided above the pair of test piece holding stages to perform a test. While trying to deform the piece horizontally,
The height of the stress load member is equal to or less than the height of the test piece.

  In the X-ray stress measurement jig described above, the stress load member is composed of four pins, and a pair of test piece holding stages are brought close to or separated from each other so that bending stress or tensile stress is applied to the test piece. X-ray stress measurement jig, load motor, ball screw that transmits the rotation of the load motor to the test piece holding stage via the gear, and for measuring the load stress of the test piece The load cell can be provided.

  The X-ray diffraction apparatus according to the present invention is characterized by mounting the above-described X-ray stress measurement jig.

  In the X-ray stress measurement jig of the present invention, a stress loading member is erected on the upper part of the test piece holding stage to deform the test piece in the horizontal direction. Furthermore, since the height of the stress load member is equal to or less than that of the test piece, the stress load member can be used regardless of whether the test piece is rotated in the horizontal direction or the vertical direction. , Does not interfere with incoming / reflected X-rays. Therefore, the stress state can be detected by irradiating the test piece with X-rays at a wide angle over the tilt angle ψ = 0 to 90 ° and the rotation angle φ = 0 to 360 ° necessary for measuring the stress by the 2D method. .

  In addition, since the X-ray stress measurement jig of the present invention has the stress loading member composed of four pins, it is possible to apply a bending stress to the test piece by bringing the pair of test piece holding stages closer to each other. It is possible to apply a tensile stress to the test piece by separating the pair of test piece holding stages.

  The X-ray stress measurement jig of the present invention transmits the rotation of the load motor to the test piece holding stage via a gear and a ball screw, and applies stress to the test piece by approaching or separating the stress load member. While being able to load, the load stress which generate | occur | produced in the test piece can be measured via a load cell.

  Moreover, since the X-ray diffractometer of the present invention is equipped with the X-ray stress measurement jig as described above, it is possible to measure the load stress by irradiating the test piece with X-rays over a wide range of angles. .

It is a perspective view of the stress constant measuring jig concerning the present invention. It is a top view of a stress constant measuring jig concerning the present invention. It is a front view of the stress constant measuring jig concerning the present invention. It is a left view of the stress constant measuring jig concerning the present invention. It is a conceptual diagram explaining the incident angle of the X-ray to a test piece. It is a conceptual diagram which shows the relationship between a tensile test piece and a stress load pin. It is a conceptual diagram which shows the relationship between a compression test piece and the member for stress loads. It is a conceptual diagram explaining the rotation angle φ and tilt angle ψ of the specimen holding stage. It is explanatory drawing of the state in which advancing of X-ray is inhibited by the beam of a test piece holding | maintenance stage.

  Examples of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the examples.

  1 to 4 are views showing a stress measuring jig for four-point bending according to the present invention, wherein 1 is a rectangular plate, 2 is a support plate disposed on the rectangular plate 1, This is a specimen holding stage. In FIG. 2, the right stage 3 is called a right stage 31 and the left stage 3 is called a left stage 32 for convenience. This X-ray stress measurement jig includes a load motor 4 for stress loading, a ball screw 5 for transmitting rotation of the load motor 4, and a load cell 6 for load stress detection. The motor 4 has a drive gear 41 at one end, and this drive gear 41 meshes with a driven gear 51 at one end of the ball screw 5. The drive gear 41 and the driven gear 51 are spur gears, but are not limited thereto, and bevel gears can be used as appropriate.

  The right stage 31 and the left stage 32 have a ball screw 5 incorporated at one end and a rail 8 incorporated at the other end. The right stage 31 and the left stage 32 approach each other when the ball screw 5 rotates in the forward direction, and move away from each other when the ball screw 5 rotates backward. At this time, the other ends of the right stage 31 and the left stage 32 slide on the rail 8.

  The right stage 31 is provided with a pair of stress-loading members 7 that are wide and perpendicular to the plate surfaces of the rectangular plate 1 and the support plate 2, and the left stage 32 is also perpendicular to the right stage 31. A pair of stress-loading members 7 having a narrow width are erected. In this embodiment, the right stress load member 7 is formed wider than the left stress load member 7, but the right stress load member 7 is narrower than the left stress load member 7. There is no problem even if it is formed. In this embodiment, the stress load member 7 is composed of four pins. Hereinafter, the right stress load member 7 is referred to as a wide-side pin 71, and the left stress load member 7 is referred to as a narrow-side pin 72.

  Since a bending test of a test piece such as ceramic is usually performed in accordance with JIS R1601, the size of the test piece is approximately 40 mm in length, 4 mm in width, and 3 mm in thickness. Corresponding to this test piece, the interval between the wide pins 71 is 30 mm, R is 2.0 to 3.0 mm, the interval between the narrow pins 72 is 10 mm, and R is 0.5 to 3. 0 mm. 2 and 3 show a state in which the test piece S is set between the wide side pin 71 and the narrow side pin 72. The test piece is set with the side surface having a thickness of 3 mm as the upper surface. Therefore, the test piece S can be bent in the horizontal direction by bringing the pin 71 and the pin 72 close to each other. Note that there is no problem even if the surface having a width of 4 mm is bent as the upper surface.

  A load cell 6 is disposed on the left stage 32. As the load cell 6, a load cell including a strain generating body and a strain gauge can be used. The load cell 6 is arranged with a stressed rod button facing sideways (rightward in FIG. 2).

  In the X-ray stress measurement jig configured as described above, when a bending load is applied to the test piece, the load motor 4 is first driven, and the ball screw is driven via the drive gear 41 and the driven gear 51. Turn 5 forward. Thereby, the other end of the right stage 31 and the left stage 32 slides on the rail 8, and the wide side pin 71 and the narrow side pin 72 approach each other, so that the bending stress can be applied to the test piece S. . While rotating the test piece holding stage in the horizontal direction and the vertical direction, the stress applied to the test piece is measured with a load cell, and X-rays are irradiated on the sample to measure a part of Debye ring.

  In the present embodiment, the upper surfaces of the wide-side pin 71 and the narrow-side pin 72 are equal to or less than the upper surface of the test piece S. That is, since it is the same but less than that, members such as the pins 71 and 72 and the test piece holding stage 3 are not disturbed by incident / reflected X-rays. Therefore, in principle, X-rays can be irradiated to the test piece at an incident angle of 0 to 180 ° + a diffraction angle (2θ). However, since an X-ray source and a detector exist, the maximum 2θ is about It is 160 °.

  Further, since the upper surfaces of the pins 71 and 72 are equal to or less than the upper surface of the test piece S, the tilt angle ψ is changed from 0 to 90 °, and the rotation angle φ is changed from 0 to 360 ° to irradiate X-rays. And X-ray stress measurement by the 2D method can be accurately performed. Please refer to FIG.

  The above is a description of the case where the stress is measured by a bending test. However, when performing a tensile test, the test piece S has a structure having a constriction as shown in FIG. If the auxiliary member 75 is used after the load member 7 is disposed to face the X member, the X-ray can be irradiated without being disturbed by the stress load member 7 as in the case of the bending test. . The stress load member 7 may be a pin or a screw.

  Further, when performing a compression test, a pair of stress-loading members 7 in the form of square blocks or the like are projected on the upper part of the test piece holding stage 3 to compress the test piece S having a rectangular parallelepiped shape or the like. . At this time, by making the upper surface of the stress load member 7 equal to or lower than the upper surface of the test piece S, the X-ray stress can be measured at a wide range of angles without being disturbed by the stress load member 7.

Claims (4)

A pair of test piece holding stages is disposed on a rectangular plate, and an X-ray stress measurement jig for applying stress to the test piece by approaching or separating the test piece holding stage,
At least one of the pair of test piece holding stages can be moved in the horizontal direction, and a stress loading member for applying stress to the test piece is provided above the pair of test piece holding stages to perform a test. While trying to deform the piece horizontally,
An X-ray stress measurement jig characterized in that a height of the stress load member is equal to or less than a height of a test piece.   The stress loading member is composed of four pins, and bending stress or tensile stress is applied to the test piece by approaching or separating the pair of test piece holding stages. X-ray stress measurement jig.   A load motor, a ball screw that transmits rotation of the load motor to a test piece holding stage via a gear, and a load cell for measuring a load stress of the test piece are provided. A jig for measuring an X-ray stress according to 1 or 2.   An X-ray diffractometer equipped with the X-ray stress measurement jig according to claim 1, 2 or 3.

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