JP2009085767A - Strain measuring apparatus by diffractometry and measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of measuring a right angle merely from one-direction measurement without requiring to add an analytical compensate, in a strain scanning method to measure a strain generating in an object to be measured. <P>SOLUTION: A surface 24A of a test specimen 24 is irradiated with X-ray and a strain of the test specimen 24 is measured from a diffraction angle 2θ of the diffracted X-ray transmitting through the test specimen 24. The technology comprises a measuring position-changing step to move and rotate the test specimen 24; an irradiating step to irradiate the test specimen 24, of which measuring position being changed at the measuring position-changing step, with a measuring wave of a given luminous flux; and a detecting step to detect a diffracted X-ray of diffracted measured wave that has transmitted through and been diffracted from the test specimen 24 and/or a measuring region set near thereto; since the test specimen 24 is rotated with a rotation center of center S of a nominal gauge volume by the irradiated X-ray of the given luminous flux, the influence of surface effect can be canceled and correct measurement can be carried out. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention irradiates an object to be measured (for example, a polycrystalline material) with a measurement wave that is an energy wave such as an X-ray, and measures the diffraction angle of a transmission measurement wave transmitted and diffracted from the object to be measured. The present invention relates to a measurement technique for measuring strain generated in a measurement object.

As a method for measuring the stress (strain) generated in the mechanical structural material, a method using a diffraction phenomenon of energy waves such as X-rays is known (for example, the sin ² Ψ method). In the sin ² Ψ method, X-rays are usually irradiated obliquely on the object to be measured. The X-rays incident on the object to be measured are reflected by the crystal lattice plane satisfying the diffraction condition in the object to be measured and are diffracted. The reflected wave reflected by the object to be measured scans the scattering angle 2θ with the angle (Ψ angle) formed by the normal line of the crystal lattice plane that caused diffraction and the normal line of the object surface to be measured fixed at a predetermined value. While measuring. The operation of the scattering angle 2θ and the measurement of the X-ray intensity are repeatedly performed while changing the ψ angle. As a result, the dependence of the X-ray scattering intensity distribution on the Ψ angle in accordance with the scattering angle 2θ is measured, and from this dependence, the component parallel to the surface of the object to be measured is measured.

In the sin ² Ψ method described above, the stress generated in the object to be measured can be accurately measured, but the X-ray intensity must be measured while scanning the scattering angle 2θ while keeping the Ψ angle constant. There is a problem that it takes a long time to measure. Further, the sin ² Ψ method can measure only the plane stress state of the object to be measured, and cannot measure the stress (strain) generated in the vertical direction of the object to be measured.

In addition, as a prior art regarding strain measurement by the sin ² Ψ method, for example, a technique disclosed in Patent Document 1 is known.

In order to solve the problems of the sin ² Ψ method described above, the strain scanning method has attracted attention. In the strain scanning method, an object to be measured is irradiated with a measurement wave such as an X-ray from an oblique direction, and a reflected wave reflected from the object to be measured is detected by a detection device through a slit or the like. For this reason, the reflected wave detected by the detection device is a reflected wave reflected from a partial area of the object to be measured (an area formed by an incident measurement wave packet and a slit on the light receiving side (hereinafter referred to as a measurement area)). Limited to Therefore, the average strain in the measurement region is obtained from the detection result detected by the detection device, and the stress generated in the object to be measured is measured.

As is apparent from the above description, in the strain scanning method, the stress distribution in an arbitrary direction generated in the measurement object can be measured by moving the measurement region set in the measurement object. Further, since a complicated operation such as scanning the scattering angle 2θ with a constant Ψ angle as in the sin ² Ψ method is not required, measurement can be performed in a short time.

  However, in the strain scanning method, when measuring strain near the surface of the object to be measured, the measurement region is set so as to protrude from the object to be measured. For this reason, there has been a problem that the detected diffraction peak is shifted and an apparent strain is measured (so-called surface effect).

  As a technique for eliminating this surface effect, a measurement method in which a single crystal analyzer is installed on the light receiving side has been proposed (Non-Patent Document 1). In this measurement method, high brightness obtained by a synchrotron radiation facility and Using high-energy X-rays as measurement waves, the high-energy X-rays have a large transmission power. Taking advantage of this characteristic, the X-rays are transmitted from the surface of the test piece, and diffracted X-rays are measured from the back surface. Measure the stress. However, even with this measurement method, the influence of the surface effect is sufficiently eliminated, and satisfactory measurement accuracy cannot be obtained.

  In order to eliminate the surface effect, (1) a method using an analyzer, (2) changing the direction of irradiation of the measurement wave on the test piece, measuring in the forward path and the return path, and the arithmetic average of the diffraction angles (3) A method of correcting analytically (for example, Patent Document 2) has also been proposed.

However, when (1) the analyzer is used, the diffraction intensity is attenuated to about 1/100, so it is difficult to perform strain scanning using the analyzer in the deflection magnet beam line. (2) Reciprocal arithmetic mean The method is disadvantageous because it requires two measurement times. In addition, the analytical correction method (3) requires complicated measurement and calculation.
JP 2004-132936 A JP 2006-17731 A P. J. et al. Withers, “Analysis of Residual Stress by Diffraction using Neutron and Synchrotron Radiation”, edited by M. H. et al. E. Fitzpatrick and A.M. Rodini, (2003) pp. 170-189, Taylor & Francis, London and New York

  The present invention has been made in view of the above-described circumstances, and its purpose is to perform analytical correction only in one direction in a strain scanning method for measuring strain generated in an object to be measured. It is an object to provide a technique capable of measuring a correct diffraction angle without adding. In addition, an object of the present invention is to provide a technique capable of obtaining a rocking effect and accurately measuring coarse particles.

The invention of claim 1 is a strain measurement apparatus using a diffraction method that irradiates a measurement wave on one side surface of a measurement object and measures the distortion of the measurement object from the diffraction angle of the diffraction measurement wave transmitted through the measurement object. Irradiating means for irradiating a measurement wave of a predetermined light flux on one side of the object to be measured; detecting means for detecting a diffracted measuring wave diffracted and transmitted through the object to be measured; and bringing the object to be measured to the irradiation means side Diffraction measurement in which the diffracted measurement wave detected by the moving means, the rotating means for rotating the object to be measured, and the detecting means is diffracted from the measurement region set in and / or in the vicinity of the object to be measured. Limiting means to limit to waves,
Is a measuring apparatus.

  Further, the invention of claim 2 is a strain measurement apparatus using a diffraction method that irradiates a measurement wave on one side of the measurement object and measures the distortion of the measurement object from the diffraction angle of the diffracted measurement wave transmitted through the measurement object. A holding unit that holds the object to be measured, an X-ray irradiation device that irradiates the object to be measured held by the holding unit with X-rays of a predetermined light beam, and diffraction that is transmitted and diffracted from the object to be measured An X-ray detection device that detects X-rays, a first slit that is disposed between the holding unit and the X-ray detection device, and passes a part of the diffracted X-rays that are transmitted and diffracted from the object to be measured; A second slit that is disposed between the first slit and the X-ray detector, passes a part of the diffracted X-rays that have passed through the first slit, and guides the X-ray detector to the X-ray detector; A moving device that moves to the X-ray irradiation device side, and the incidence of X-rays on the object to be measured A rotating device that rotates the holding unit to change the position, and a light receiving side that moves the first slit, the second slit, and the X-ray detection device in accordance with the position change of the object to be measured by the moving device and the rotating device. A measuring apparatus comprising: a driving device; and a control unit that controls the X-ray irradiation device, the X-ray detection device, the moving device, the rotating device, and the light receiving side driving unit.

  Further, the invention of claim 3 is a strain measurement method by a diffraction method in which a measurement wave is irradiated on one side of the measurement object, and the distortion of the measurement object is measured from the diffraction angle of the diffraction measurement wave transmitted through the measurement object. A measurement position changing step of moving and rotating the measurement object; an irradiation step of irradiating the measurement object whose measurement position has been changed by the measurement position change step with a measurement wave of a predetermined luminous flux; and the measurement object Detecting a diffracted measurement wave transmitted and diffracted from a measurement region set in and / or in the vicinity of the object, with the center of the nominal gauge volume by the X-ray of the predetermined light beam irradiated as the rotation center And measuring the object to be measured.

  According to the configuration of claim 1, on the surface side of the object to be measured, the detected diffraction peak shifts due to the so-called surface effect, and the apparent distortion is measured, resulting in a measurement error. By rotating the object to be measured around the center of the gauge volume during the measurement of the diffracted X-ray, the influence of the surface effect can be canceled and accurate measurement can be performed. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  According to the configuration of claim 2, the holding unit for holding the object to be measured moves to the X-ray irradiation apparatus side, rotates the object to be measured around the center of the nominal gauge volume, and sets the measurement position. When the measurement position is changed, the light receiving side driving means is actuated accordingly, and the X-ray detection device, the first slit, and the first slit are placed at a position where the diffracted X-rays transmitted and diffracted from the measurement object can be detected 2 slits move.

  Then, by rotating the object to be measured around the gauge volume during the X-ray diffraction measurement, the influence of the surface effect can be canceled and accurate measurement can be performed. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  According to the third aspect of the present invention, the measurement object rotates around the center of the gauge volume during the measurement of the X-ray diffraction, thereby canceling the influence of the surface effect and enabling accurate measurement. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below do not limit the contents of the present invention described in the claims. In addition, all the configurations described below are not necessarily essential requirements of the present invention. In each embodiment, by employing a strain measuring device and a measuring method based on a diffraction method different from the conventional one, a strain measuring device and a measuring method based on a diffraction method which are not conventional can be obtained, and the strain measuring device and the measuring method based on the diffraction method are obtained. Respectively.

  A strain measuring method according to the first embodiment embodying the present invention will be described. First, the procedure for calculating the stress from the diffraction angle measured by the conventional reflective strain scanning method and the principle of the reflective strain scanning method will be briefly described. In the following description, the same parts as those in the background art described above are denoted by the same reference numerals, and description thereof is omitted.

FIG. 10A shows a coordinate system set for the test piece. As shown in FIG. 10A, the stress (strain) in the plane parallel to the surface of the test piece is σ ₁ (ε ₁ ), σ ₂ (ε ₂ ), and the stress (strain) in the depth direction of the test piece Is σ ₃ (ε ₃ ), the relationship of triaxial stress is given by the following equation.
ε ₁ = {σ ₁ −ν (σ ₂ + σ ₃ )} / E
ε ₂ = {σ ₂ −ν (σ ₁ + σ ₃ )} / E (1)
ε ₃ = {σ ₃ −ν (σ ₁ + σ ₂ )} / E
Here, the relationship between the lattice plane spacing d and the strain ε is given by the following equation (d ₀ is the unstrained lattice spacing).
ε = (d−d ₀ ) / d ₀ (2)
The relationship between the lattice plane distance d and the diffraction angle θ is given by the following Bragg condition (λ is the wavelength of the measurement wave).
λ = 2 dsin θ (3)
Here, since the wavelength λ of the measurement wave and the undistorted lattice plane interval d ₀ are known, the lattice plane interval d can be calculated from the above equation (3) if the diffraction angle θ can be measured. The strain ε can be calculated from d (the above equation (2)). Therefore, the diffraction angle theta ₁ for 3-axis directions of the test piece, theta _2, if measured theta _3, which diffraction angles theta _1, theta _2, can be calculated lattice spacing d _1, d _2, d ₃ from the theta ₃ The strains ε ₁ , ε ₂ , ε ₃ can be calculated from the lattice spacings d ₁ , d ₂ , d ₃ . If the strains ε ₁ , ε ₂ , and ε ₃ can be calculated, all of the stresses in the three axial directions of the test piece can be calculated using these values in the above equation (1).

FIG. 10B shows a schematic diagram of the optical system when measuring the strain ε ₃ in the depth direction of the test piece. When measuring the strain ε ₃ in the depth direction, the test piece is set with the xy plane (surface) of the test piece facing upward (FIG. 10B). The set test piece is irradiated with measurement waves (for example, energy waves such as X-rays and neutrons) from obliquely above. The measurement wave to be irradiated is changed into a predetermined light flux by the diverging slit Sd. The diffraction measurement wave diffracted by the test piece is detected by a detection device (not shown) through the light receiving slit Sr. By detecting the diffracted measurement wave while changing the incident angle to the test piece, the relationship of “diffracted measured wave intensity−incident angle” is obtained, and the angle at which the diffracted measured wave intensity peaks (ie, the diffraction angle) ) Can be specified. The calculation of the strain ε ₃ from the specified diffraction angle can be performed by the procedure already described.

As is clear from FIG. 10 (b), the measurement wave detected by the detector is a diffraction measurement reflected from the measurement region (diamond region in the figure) limited by the diverging slit Sd and the light receiving slit Sr. Only waves are detected. Therefore, the strain ε ₃ obtained from the specified diffraction angle is an average strain in this measurement region. Therefore, the strain distribution in the Z direction of the test piece can be obtained by measuring the diffraction angle while moving the measurement region in the Z direction of the test piece.

FIG. 10C is a schematic diagram of the optical system when measuring the in-plane strain (specifically, the x direction) of the test piece. When measuring the strain ε ₁ in the x direction as shown in FIG. 10C, the xy plane (surface) of the test piece faces the incident side of the measurement wave, and the direction in which the measurement region is moved is The test piece is set so as to coincide with the x direction of the test piece. Irradiation of the measurement wave to the test piece, detection of the reflected wave from the test piece, identification of the diffraction angle, and the like are performed in the same manner as described above.

The strain ε _{2 in} the y direction can be measured only by changing the direction in which the test piece is set. That is, the test piece may be set so that the xy plane (front surface) of the test piece faces the incident side of the measurement wave and the direction in which the measurement area is moved coincides with the y direction of the test piece.

  Next, the transmission type rotational strain scanning method of the present invention will be described. In the present invention, high-energy synchrotron radiation X-rays are used as measurement waves, and X-rays are transmitted from the surface of the test piece, and diffracted X-rays are measured from the back, as in Non-Patent Document 1, and the residual stress of the test piece is measured. A transmission type strain measurement method is used.

  The principle related to the measurement is the same as that of the reflection type strain scanning method shown in FIG. 10, and will be further described with reference to FIG. As shown in FIG. 1, a test piece 24 that is an object to be measured is set on a Z-axis stage 1 that is a holding unit. The test piece 24 is set with the surface 24A in the vertical direction facing the X-ray irradiation device 10 side and the back surface 24B in the vertical direction facing the X-ray detection device (X-ray counter) 20 side. That is, one side in the thickness direction (Z direction) of the test piece 24 is the surface 24A, and the other side is the back surface 24B. In addition, the test piece 24 is a rectangular parallelepiped with which the outer surfaces which oppose are parallel.

  The X-ray irradiation apparatus 10 emits high-energy radiated light X-rays, and a diverging slit 12 is disposed at the exit of the X-ray irradiation apparatus 10. For this reason, the X-rays emitted from the X-ray irradiation apparatus 10 become an X-ray bundle having a predetermined width by the diverging slit 12 and enter the test piece 24. Therefore, in this embodiment, the X-ray irradiation apparatus 10 and the diverging slit 12 constitute the irradiation means referred to in the claims. In addition, light receiving slits 16 and 18 are arranged on the entrance side of the X-ray detector 20. For this reason, the X-ray detector 20 detects only X-rays that have passed through the light receiving slits 16 and 18. Therefore, in this embodiment, the light receiving slits 16 and 18 correspond to the limiting means in the claims.

  Further, the diffracted measurement wave detected by the X-ray detection device 20 is detected only from the diffracted measurement wave transmitted and diffracted from the measurement region (diamond region in the figure) limited by the divergence slit 12 and the light receiving slits 16 and 18. Is done. And the said measurement area | region becomes a gauge volume which evaluates distortion. By moving the Z-axis stage 1 in parallel to the X-ray irradiation apparatus 10 side, the test piece 24 moves to the X-ray irradiation apparatus 10, and the gauge volume moves from the front surface 24A to the back surface 24B of the test piece 24 while diffracting X-rays. Is measured. The diffraction angle 2θ is expressed by the above-described equation (2).

  Therefore, since the wavelength λ of the X-ray is a constant, the lattice plane distance d can be obtained by measuring the diffraction angle 2θ. Then, the strain of the material at that position can be obtained from the change in the lattice spacing d at any position. The above is the explanation of the principle of the transmission type rotational strain scanning method.

  Hereinafter, the surface effect in the transmission type rotational strain scanning method will be considered. As shown in the schematic illustration of FIG. 2, when the gauge volume crosses the surface of the test piece 24, the shape of the gauge volume subjected to diffraction is different from the nominal shape. For this reason, the diffraction center of the actual gauge volume is at a position off the center of the nominal gauge volume. As a result, the measured diffraction angle 2θ is shifted. This phenomenon is called a surface aberration effect, which makes accurate strain measurement difficult.

  The influence of the surface effect differs between the forward path shown in FIG. 2A and the return path shown in FIG. 2B. In order to show this, the values of diffraction angles measured in the forward path and the return path are shown in FIG. In the example of FIG. 3, since the material obtained by annealing S45C is used for the test piece 24, the test piece 24 has no residual stress, and therefore should exhibit a certain diffraction angle. However, as can be seen from the figure, when the gauge volume is in the vicinity of the surface 24A (Z = 0 mm) and the back surface 24B (Z = 4 mm), the correct diffraction angle 2θ cannot be measured. In FIG. 3, the average value of diffraction angles obtained in the forward path and the return path is also displayed. By using the average value, the value of the diffraction angle 2θ becomes substantially horizontal in the graph, and the residual stress is applied to the test piece 24. It is clear that there is no error, but two measurements are required.

  In the strain scanning method, if the measurement region formed by the divergence slit 12 and the light receiving slits 16 and 18 is different from the diffraction region where the measurement wave is actually diffracted (the region where the object to be measured exists), the apparent scanning method is apparent. Strain is measured.

FIG. 11 schematically shows two slits arranged on the light receiving side (X-ray detection device 20 side) and an optical system formed by the slits. As shown in FIG. 11, in this embodiment, the two slits G1 and G2 are arranged apart from each other by a predetermined distance R2 in the optical axis direction. By disposing the two slits G1 and G2 apart from each other in the optical axis direction, the divergence angle of the reflected wave passing through the two slits G1 and G2 can be limited to α. As a result, the influence of the divergence of the reflected wave is suppressed, and the measurement accuracy can be increased. As is apparent from FIG. 11, the divergence angle α is obtained by the following equation (r is the width of the slits G1 and G2).
α / 2 = tan-1 (r / R2) (4)
FIG. 12 is a schematic view showing the overall configuration of the optical system of the present embodiment, and FIG. 13 shows an enlarged apparatus gauge volume shown in FIG. As shown in FIG. 12, the measurement wave is converted into a light flux having a width r by the diverging slit Ds, and is incident on the test piece. The diffraction measurement wave diffracted by the test piece 24 is guided to the X-ray detector by the light receiving slits RS1 and RS2 having a width r. Since the divergence angle of the diffracted measurement wave passing through the light receiving slits RS1 and RS2 is α, the device gauge volume extends above and below the central rhombus region (nominal gauge volume). And as shown in FIG. 13, the center of a nominal gauge volume is the code | symbol S. FIG. Conventionally, it is necessary to measure the above-described apparent strain and analytically correct the measured value.

  On the other hand, in this embodiment, as shown in FIG. 4, the test piece 24 is placed and held on the rotary stage 2, and the rotary stage 2 is rotated around the center S of the nominal gauge volume, that is, the rotary stage. The center of rotation 2 is aligned with the center S of the nominal gauge volume, and the Z-axis stage 1 is provided on the rotation stage 2.

  In addition, a rotation device 3 that rotates the rotation stage 2 and a moving device 4 that drives the Z-axis stage 1 to move back and forth from the X-ray detection device 20 side to the X-ray irradiation device 10 side (Z direction) are provided. The direction of horizontal movement from the X-ray detection device 20 side to the X-ray irradiation device 10 side is the Z direction. Since the drive mechanism of the moving means 4 is provided between the rotary stage 2 and the Z-axis stage 1, when a control cord or the like is connected to the moving means 4, it rotates when the rotary stage 2 rotates. Wrapping around stage 2 makes measurement impossible. In order to prevent this, the slip ring 5 is installed on the rotary stage 2 so that the movement of the Z-axis stage 1 can be controlled while rotating. That is, the rotary stage 2 on the slip ring 5 rotates, the lower part of the slip ring 5 is fixed, and a control signal and power are transmitted to the moving means 4 through the slip ring 5.

  In addition, the light receiving side driving device 6 that moves the light receiving slit 16 that is the first slit, the light receiving slit 18 that is the second slit, and the X-ray detection device 20 according to the position change of the object to be measured by the moving device 4 and the rotating device 3. Prepare. Then, the control means 7 controls the X-ray irradiation device 10, the X-ray detection device 20, the moving device 4, the rotating device 3, and the light receiving side driving means 6 to detect the diffraction angle 2θ.

  According to this method, since the test piece 24 rotates around the center S of the nominal gauge volume during the measurement of diffracted X-rays, it is possible to cancel the influence of the surface effect described above.

  The diffraction peak is measured at each depth Z while rotating the test piece 24, and the Z-axis stage 1 is advanced to the X-ray irradiation apparatus 10 side. That is, the sample piece 24 and the Z-axis stage move as shown in FIGS. Since the movement of the X-ray irradiation apparatus 10 and the X-ray detection apparatus 20 which are optical systems and the test piece 24 are relative, the optical system and gauge volume may rotate without the test piece 24 rotating. In a synchrotron radiation facility, it is not realistic, so it is not mentioned in this case.

  FIG. 7 shows a state in which a rotational strain scanning stage was manufactured in order to carry out the “transmission type rotational strain scanning method” and mounted on a diffraction device for high-intensity synchrotron radiation. “X-rays” (high-energy synchrotron radiation X-rays) shown in the figure are incident on the test piece 24 from the left side in the figure, and the X-rays diffracted by the test piece 24 travel to the right side (X-ray detection device side) in the figure. The Z-axis stage 1 rotates on the rotary stage 2, and a test piece 24 is set on the Z-axis stage 1. The diffraction angle 2θ is measured each time while rotating and scanning in the Z direction.

What is the thickness of the specimen 24 in the Z direction? In this example, it is 4 mm, and FIG. 8 shows the experimental result by the above-mentioned “transmission type rotational strain scanning method” together with the result of FIG. Thus, it can be seen that the surface effect is corrected by the transmission type rotational strain scanning method, and a constant diffraction angle 2θ can be measured, and the effect of the surface correction of the transmission type rotational strain scanning method has been proved.

  Next, the oscillation effect of the rotational strain scanning method in the diffraction measurement of coarse grains was examined.

  The rotational strain scanning method of this embodiment is effective not only for correcting the surface effect but also for measuring diffraction lines of coarse grains having large crystal grains. As the test piece 24, shot peening was applied to the surface 24A (Z = 0 mm) of austenitic stainless steel SUS304L (plate thickness 5 mm) to introduce compressive residual stress. FIG. 9B shows the result of strain scanning of the test piece 24 in which residual stress is introduced on the surface 24A side by the transmission type rotational strain scanning method. In the figure, the vertical axis represents the diffraction intensity, and the diffraction angle 2θ at the depth Z is used as a coordinate.

  In a general strain scanning method, the vicinity of the surface 24A is coarse, so that there are not enough crystal grains to be diffracted, the diffraction line cannot be measured, and the strain cannot be measured.

  On the other hand, in the transmission type rotational strain scanning method of the present invention, the test piece 24 is rotated around the gauge volume, so that sufficient crystal grains can be obtained. As a result, as shown in FIG. 9B, the diffraction curve can be clearly measured even on the surface (surface 24A) subjected to shot peening, and the diffraction angle 2θ can be determined sufficiently.

  Thus, it is clear that the transmission-type rotational strain scanning method is advantageous in measuring coarse grains in addition to correcting the surface effect.

  As described above, in this embodiment, corresponding to claim 1, X-rays that are measurement waves are applied to the surface 24A that is one side surface of the test piece 24 that is the object to be measured, and the diffraction that is the diffraction measurement wave that is transmitted through the test piece 24. An X-ray irradiating apparatus 10 that is a diffractometric strain measuring apparatus that measures the strain of the test piece 24 from the X-ray diffraction angle 2θ, and that is an irradiating means for irradiating the surface 24A of the test piece 24 with X-rays of a predetermined light beam; Rotating the test piece 24, the X-ray detection device 20 as detection means for detecting diffracted X-rays diffracted and transmitted through the test piece 24, the moving device 4 as moving means for moving the test piece 24 toward the X-ray irradiation device 10 Limiting means for limiting the diffracted X-rays detected by the rotating device 3 and the X-ray detector 20 to the diffracted X-rays diffracted from the measurement region set in and / or in the vicinity of the test piece 24 With light receiving slits 16 and 18 Therefore, conventionally, on the surface side of the test piece 24, the detected diffraction peak is shifted due to the so-called surface effect, and the apparent distortion is measured, resulting in a measurement error. By rotating the test piece 24 around the center S of the gauge volume during the measurement, the influence of the surface effect can be canceled and accurate measurement can be performed. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  In this way, in this embodiment, the limiting means is disposed between the test piece 24 as the object to be measured and the X-ray detection device 20 as the detection means, and the diffraction measurement wave from the test piece 24 toward the X-ray detection device 20. A light receiving slit 16 that is a first blocking member that blocks a part of the diffracted X-rays, and a part of the diffracted X-rays that are disposed between the light receiving slit 16 and the X-ray detection device 20 and pass through the light receiving slit 16 Since it has the light-receiving slit 18 that is the second blocking member to block, the diffracted X-rays detected by the X-ray detection device 20 are more limited by the light-receiving slits 16 and 18 and reduce the influence of the diffracted measurement wave divergence. Can do. In particular, when the light receiving slits 16 and 18 are spaced apart in the optical axis direction, only the diffracted X-rays substantially parallel to the optical axis are detected by the detecting means.

  In this way, in this embodiment, corresponding to claim 2, X-rays that are measurement waves are applied to the surface 24A that is one side of the test piece 24 that is the object to be measured, and the back surface 24B of the test piece 24 is transmitted. A strain measurement apparatus using a diffraction method that measures strain of a test piece 24 from a diffraction angle 2θ of diffracted X-rays. The Z-axis stage 1 is a holding unit that holds a test piece 24 that is an object to be measured. An X-ray irradiation apparatus 10 that irradiates the held test piece 24 with X-rays of a predetermined light beam, an X-ray detection apparatus 20 that detects diffracted X-rays transmitted and diffracted from the test piece 24, the Z-axis stage 1 and X The light receiving slit 16 that is disposed between the light detecting device 20 and passes a part of the diffracted X-rays transmitted and diffracted from the test piece 24, and between the light receiving slit 16 and the X-ray detecting device 20. Placed through the light receiving slit 16 The light-receiving slit 18 that is a second slit that allows a part of the diffracted X-rays to pass to the X-ray detector 20, the moving device 4 that moves the test piece 24 toward the X-ray irradiation device 10, and the test piece 24. The rotating device 3 that rotates the Z-axis stage 1 to change the incident angle of X-rays, and the light receiving slit 16 according to the position change (including change of orientation) of the test piece 24 by the moving device 4 and the rotating device 3. 18 and the light receiving side driving device 6 for moving the X-ray detection device 20, and a control means for controlling the X-ray irradiation device 10, the X-ray detection device 20, the moving device 4, the rotating device 3 and the light receiving side driving means 6. Thus, the Z-axis stage 1 holding the test piece 24 can be moved to the X-ray irradiation apparatus 10 side, and the test piece 24 can be rotated around the center S of the nominal gauge volume to change the measurement position. If you change the measurement position, In response to this, the light receiving side driving means 6 operates, and the X-ray detector 20 and the light receiving slits 16 and 18 move to a position where the diffracted X-rays transmitted and diffracted from the test piece 24 can be detected.

  Then, by rotating the test piece 24 around the center of the gauge volume during the measurement of X-ray diffraction, the influence of the surface effect can be canceled and accurate measurement can be performed. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  In this way, in this embodiment, corresponding to claim 3, the diffraction measurement wave transmitted through the test piece 24 by irradiating the surface 24A, which is one side surface of the test piece 24, which is an object to be measured, with the X-ray as the measurement wave. This is a strain measurement method by a diffraction method for measuring the strain of the test piece 24 from the diffraction angle 2θ of the diffracted X-ray, and the measurement position is changed by the measurement position changing step of moving and rotating the test piece 24 and the measurement position changing step. Irradiation step of irradiating the modified test piece 24 with a measurement wave of a predetermined light beam, and detection for detecting a diffracted X-ray as a diffracted measurement wave transmitted and diffracted from a measurement region set in and / or in the vicinity of the test piece 24 And the test piece 24 is rotated about the center S of the nominal gauge volume by the X-ray of the irradiated predetermined light beam as the rotation center, so that the influence of the surface effect can be canceled and accurate measurement can be performed. In addition, a rocking effect can be obtained, and coarse particles can be accurately measured.

  Further, as an effect on the embodiment, the control means 7 drives the rotating device 3, the moving device 4 and the light receiving side driving device 6 to change the incident angle to the test piece 24 from the X-ray irradiation device 10 to the X-ray. And the X-ray detection apparatus 10 detects X-rays transmitted and diffracted from the test piece 24, and the X-ray diffraction angle 2θ is specified from the relationship of “incident angle−X-ray intensity” obtained thereby. Can do.

  In addition, this invention is not limited to the said Example, A various deformation | transformation implementation is possible. For example, although high-energy synchrotron radiation X-rays from a synchrotron radiation source are used as measurement waves in the embodiments, other energy waves such as neutron beams may be used.

It is a side view of the principal part of the distortion | strain measuring apparatus which shows Example 1 of this invention. It is explanatory drawing which shows the azimuth | direction relationship between the to-be-measured object and a gauge volume in an outward path and a return path. It is a graph which shows the value of the diffraction angle measured on the outward path and the return path. It is a side view of the principal part of a distortion measuring device same as the above. It is a top view of the principal part of a distortion measuring device same as the above. It is a block diagram around a control means same as the above. It is a perspective view of the stage for transmission type | mold rotational distortion scanning same as the above. It is a graph which shows the value of a diffraction angle same as the above. FIG. 9 is a graph showing the relationship between the X-ray intensity, the diffraction angle, and the depth. FIG. 9A shows a conventional strain scanning method, and FIG. 9B shows a transmission type rotational scanning method. It is explanatory drawing explaining the optical system of a double slit same as the above. It is a schematic explanatory drawing which shows the optical system of a double slit same as the above. It is a schematic explanatory drawing which shows the optical system formed by a diverging slit and two light receiving slits same as the above. It is the schematic explanatory drawing which expanded the part of the gauge volume of FIG. 11 same as the above.

Explanation of symbols

1 Z-axis stage (holding part)
2 Rotating stage 3 Rotating device (Rotating means)
4. Moving device (moving means)
5 Slip ring 6 Light-receiving side drive device 7 Control means 10 X-ray irradiation device (irradiation means)
12 Divergence slit 16 Light receiving slit (first shielding means / first slit)
18 Light receiving slit (second shielding means / second slit)
20 X-ray detection device (detection means)
24 Test piece (measurement)
S center

Claims (3)

A diffraction measuring device that irradiates a measurement wave on one side of the object to be measured and measures the distortion of the object to be measured from the diffraction angle of the diffraction measurement wave transmitted through the object to be measured,
Irradiating means for irradiating a measurement wave of a predetermined light flux on one side surface of the object to be measured;
Detecting means for detecting a diffracted measurement wave diffracted and transmitted through the object to be measured;
Moving means for moving the object to be measured toward the irradiation means;
Rotating means for rotating the object to be measured;
Limiting means for limiting the diffracted measurement wave detected by the detecting means to a diffracted measurement wave diffracted from a measurement region set in and / or in the vicinity of the measured object
A strain measurement apparatus using a diffraction method, comprising: A diffraction measuring device that irradiates a measurement wave on one side of the object to be measured and measures the distortion of the object to be measured from the diffraction angle of the diffraction measurement wave transmitted through the object to be measured,
A holding unit for holding the object to be measured;
An X-ray irradiation apparatus for irradiating the object to be measured held by the holding unit with X-rays of a predetermined luminous flux;
An X-ray detector for detecting diffracted X-rays transmitted and diffracted from the object to be measured;
A first slit that is disposed between the holding unit and the X-ray detection device and transmits a part of the diffracted X-rays transmitted and diffracted from the object to be measured;
A second slit disposed between the first slit and the X-ray detection device, and passing a part of the diffracted X-rays that have passed through the first slit to guide the X-ray detection device;
A moving device for moving the object to be measured to the X-ray irradiation device side;
A rotating device that rotates a holding unit to change an incident angle of X-rays to the object to be measured;
A light receiving side driving device that moves the first slit, the second slit, and the X-ray detection device in accordance with a change in position of the object to be measured by the moving device and the rotating device;
Control means for controlling the X-ray irradiation device, the X-ray detection device, the moving device, the rotating device, and the light receiving side driving means;
A strain measurement apparatus using a diffraction method, comprising: It is a strain measurement method by a diffraction method in which a measurement wave is irradiated on one side surface of a measurement object, and the distortion of the measurement object is measured from the diffraction angle of the diffraction measurement wave transmitted through the measurement object.
A measurement position changing step of moving and rotating the object to be measured;
An irradiation step of irradiating the measurement object whose measurement position has been changed by the measurement position changing step with a measurement wave of a predetermined luminous flux;
A detection step of detecting a diffracted measurement wave transmitted and diffracted from a measurement region set in and / or in the vicinity of the object to be measured;
With
A strain measurement method by a diffraction method, characterized in that the object to be measured is rotated about the center of a nominal gauge volume by X-rays of an irradiated predetermined light beam as a rotation center.