JP3474101B2 - Pole measurement method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pole measuring method for analyzing a polycrystalline sample using an X-ray diffractometer.

[0002]

2. Description of the Related Art As a method for analyzing a polycrystalline sample using an X-ray diffractometer, there is a pole measuring method for analyzing the orientation (texture) of the sample with a pole figure. The pole figure is a polar net (stereo projection diagram) as shown in FIG. 5, showing the poles of a crystal constituting the sample with respect to a specific lattice plane. Here, the pole means an intersection of a sphere centered on the crystal that constitutes the sample and a normal line of the lattice plane.

FIG. 3 is a schematic diagram showing an optical system used in a conventional pole measuring method by the reflection method. The sample S is rotatable about an axis A in the surface and rotates in-plane about an axis B orthogonal to the sample surface. The X-ray a is applied onto the axis A of the sample surface from the angle of incidence θ. And
The sample S is rotated about the axis A (hereinafter also referred to as α rotation) and is also rotated about the axis B (hereinafter also referred to as β rotation), with respect to the optical axis of the incident X-ray a. The intensity of the diffracted X-ray b reflected from the sample surface at an angle of 2θ is measured by the X-ray detector 1 fixed at a predetermined position.

The intensity of the diffracted X-ray b measured by the X-ray detector 1 is displayed on the polar net with the rotation angle α around the axis A and the rotation angle β around the axis B of the sample S as variables.
As a result, a pole figure is created.

Here, the polar net has a rotation angle α in the radial direction, and is defined as α = 90 ° at the center and α = 0 ° at the outer periphery. Further, the rotation angle β is set in the circumferential direction of the polar net. FIG. 6 shows cold rolled 70-30 Cu
The example of the pole figure which made (111) of Zn a pole is shown.

Incidentally, in the reflection method for measuring the intensity of the diffracted X-ray reflected by the sample, generally, only the region where the rotation angle α is large (for example, α = 15 ° to 90 °) can be measured, and the rotation angle α is small. The area (for example, α = 0 ° to 45 °) is
It is measured by a transmission method that detects the intensity of diffracted X-rays that have passed through the sample.

[0007]

As described above, in the conventional pole measurement, the sample S was rotated by α and the sample S was rotated by β.
In order to rotate the device around a plurality of axes A and B, it is necessary to incorporate a complicated and highly accurate rotation mechanism into the sample stage. In particular,
The α rotation is indispensable for pole measurement, and therefore the sample stage used for general X-ray diffraction measurement cannot be used for pole measurement, and it was necessary to manufacture a dedicated sample stage.

Further, in order to rotate the sample S by α, in the area away from the axis A of the incident X-ray a, the position of the irradiation surface changes with the rotation of the sample S and the position on the X-ray detector 1 is changed. The focus is out of focus. Therefore, conventionally, the diffraction X-ray b
The width (the width in the vertical direction in the figure) was narrowed down so that only the diffracted X-ray b in the central portion where the focus was made incident on the X-ray detector 1. When the aperture is narrowed down, the intensity of the diffracted X-ray b is inevitably weakened and the detection accuracy is lowered.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a pole measuring method by a reflection method that does not require rotation of a sample around an arbitrary axis in the sample surface.

[0010]

In order to achieve the above object, the pole measuring method of the present invention is characterized by including the following operations (a) to (c).

(B) The surface of the sample is irradiated with X-rays. (B) The sample is rotated in-plane around an arbitrary axis orthogonal to the surface, and the rotation angle β is measured. (C) The X-ray detector is moved along the Debye ring drawn by the diffracted X-ray from the sample, and the intensity of the diffracted X-ray reflected or transmitted from the sample is measured.

The pole measuring method of the present invention is applied to the pole measuring of a polycrystalline sample by the reflection method or the transmission method. That is, the surface of the sample mounted on the X-ray diffractometer is irradiated with X-rays, and the intensity of the diffracted X-rays reflected or transmitted from the sample surface is measured by an X-ray detector.

The sample is rotated in-plane (β rotation) around an arbitrary axis orthogonal to the sample surface as in the conventional pole measuring method, but rotation about the axis in the sample surface (α rotation) is required. do not do. Therefore, it is possible to use a sample stage used for general X-ray diffraction measurement. Further, it is not necessary to narrow down the diffracted X-rays, and it becomes possible to make diffracted X-rays of high intensity incident on the X-ray detector.

Now, as shown in FIG. 4, it is known that when the polycrystalline sample S is irradiated with X-ray a, the diffracted X-ray b appears in a conical shape around the optical path of the incident X-ray a. Then, when this diffracted X-ray b is projected on the flat plate film Z orthogonal to the optical path of the incident X-ray a, the diffracted X-ray b is recorded in a ring shape. The ring 10 drawn by this diffracted X-ray b is called a Debye ring.

In the present invention, by moving the X-ray detector along the Debye ring drawn by the diffracted X-rays from the sample,
Diffracted X-rays in the direction measured by α rotation of the sample are made incident on the X-ray detector.

In order to record the measurement results obtained by the present invention on the polar net, it is necessary to convert the angle φ of the X-ray detector into the rotation angle α of the sample. Therefore, the angle φ of the X-ray detector is converted into the rotation angle α of the sample by the above-mentioned equation 1, and the measured diffracted X-ray intensity is recorded in the polar net.

As a result of replacing the α rotation of the sample with the movement of the X-ray detector along the Debye ring, an error also occurs in the orientation of the diffracted X-ray measured by the β rotation of the sample. Therefore, in the present invention, the correction value ∂β for correcting the error is calculated by the above-described equation 2. That is, β + ∂β is taken in the circumferential direction of the polar net, and the measured diffraction X-ray intensity is recorded.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. FIG. 1 is a schematic diagram showing an optical system used in the pole measuring method according to the embodiment of the present invention. The sample (polycrystalline sample) S rotates in-plane (β rotation) about an axis B orthogonal to the surface. When this sample S is irradiated with X-rays from the direction of the incident angle θ from the X-ray source 2, the diffracted X-rays b appear at an angle of 2θ with respect to the optical axis of the incident X-ray a.

As described above, this diffracted X-ray b appears in a conical shape with the optical axis of the incident X-ray a as the center. Then, the Debye ring 10 is drawn on a virtual plane orthogonal to the optical axis of the incident X-ray a. Here, the virtual plane may be set at an arbitrary position on the optical axis of the incident X-ray a.

The X-ray detector 1 measures the diffracted X-rays b reflected from the sample surface at an angle of 2θ on the Debye ring 10. That is, the X-ray detector 1 is configured to be movable along the Debye ring 10 and sequentially moves in steps along the Debye ring 10 from a predetermined origin to determine the intensity of the diffracted X-ray b at each moving position. taking measurement.

Now, when displaying a pole figure on a polar net, the sample is usually rotated in the radial direction of the polar net with the X-ray detector 1 fixed and an arbitrary axis in the sample surface as the center. The rotation angle α when taken is taken. Therefore, when creating a pole figure from the measurement results of this embodiment, it is necessary to convert the angle φ into the rotation angle α.

Here, as shown in FIG. 1, the X-ray detector 1
Is moved along the Debye ring 10 from h0 to h1, and the angle about the X-ray irradiation point O on the sample surface at this time is φ. In addition, with the X-ray detector 1 fixed at h0, the diffracted X-rays output at h1 are taken as α of the sample S.
It is assumed that the sample S is moved to h0 by rotation, and the rotation angle of the sample S at that time is α. These angle φ and rotation angle α
The relational expression of the above-described mathematical expression 1 is established between and. Therefore, by converting the angle φ into the rotation angle α by using the relational expression of Expression 1, a pole figure can be created in the same manner as the conventional pole measuring method.

As a result of replacing the α rotation of the sample S with the movement of the X-ray detector 1 along the Debye ring 10, an error also occurs in the orientation of the diffracted X-ray b measured by the β rotation of the sample S. . Therefore, the correction value ∂β for correcting the error is calculated by using the correction equation of the above-mentioned equation 2 and added to the actual rotation angle β. That is, a pole figure is created with β + ∂β.

FIG. 2 (a) is a diagram showing an optical system for pole measurement by symmetric reflection, and FIG. 2 (b) is a diagram showing an optical system for pole measurement by asymmetric reflection. When the incident angle of the X-ray a with respect to the sample S and the reflection angle of the diffracted X-ray b from the sample S are the same angle (both θ) as shown in FIG.
The area of the diffracted X-ray b that can be measured by the reflection method is limited to the narrow area indicated by L in FIG.

Therefore, as shown in FIG.
If the incident angle θ of the X-ray a with respect to is set to a low angle and adjusted so that the diffracted X-ray b is reflected from the sample S at a wide angle θ ′, a measurable region by the reflection method (L in the figure (b)). (Indicated by ‘) is preferable because it can be expanded.

The present invention is not limited to the above embodiment. For example, when a pole figure is created according to the conventional convention, conversion to the rotation angle α and correction of the rotation angle β as described above are required, but based on the measurement result of the method of the present invention, the unique pole It is also possible to create a diagram and analyze the orientation and the like of the polycrystalline sample. In that case, the angle φ of the X-ray detector and the in-plane rotation angle β of the sample can be directly used as variables.

[0027]

As described above, according to the present invention,
Since it is not necessary to rotate the sample around an arbitrary axis on the sample surface, it is possible to perform pole point measurement using a sample table with a simple structure used for general X-ray diffraction measurement. The versatility of the sample table can be expanded. Further, in the pole point measurement, there is no limitation on the X-ray width associated with the rotation of the sample about an arbitrary axis in the sample surface, and the clear diffraction X-ray intensity can be measured.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an optical system used in a pole measuring method according to an embodiment of the present invention.

FIG. 2 is a diagram showing an optical system for pole measurement by symmetrical reflection and asymmetric reflection.

FIG. 3 is a schematic diagram showing an optical system used in a conventional pole measuring method.

FIG. 4 is a perspective view showing a Debye ring drawn by a diffracted X-ray output from a sample.

FIG. 5 is a diagram showing a general polar net.

FIG. 6 Cold rolled 70-30 CuZn (111)
It is the pole figure which made the pole.

[Explanation of symbols]

1: X-ray detector 2: X-ray source 10: Debye ring

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Go Fujinawa 3-9-12 Matsubara-cho, Akishima-shi, Tokyo Within Rigaku Denki Co., Ltd. (72) Inventor table Kazuhiko 3-9-12 Matsubara-cho, Akishima-shi, Tokyo Rigaku Denki (56) References JP-A-5-322806 (JP, A) JP-A-61-75243 (JP, A) JP-A-9-113468 (JP, A) Fisker R and 2 others, Use of Image -Processing Tools foot Texture Analysis of High-Energy X-ray Synchrotron Data, J. Mol. App l. Crystallogr. , October 1, 1998, vol. 31, no. 5, p. 647-653 (58) Fields investigated (Int.Cl. ⁷ , DB name) G01N 23 / 00-23 / 227 JISST file (JOIS)

Claims (3)

(57) [Claims] 1. A pole measuring method for measuring a pole distribution of a polycrystalline sample, which comprises the following processes (a) to (d) : (A) Irradiate the surface of the sample with X-rays. (B) While rotating the sample in-plane around an arbitrary axis orthogonal to the surface, measure the rotation angle β. (C) Along the Debye ring drawn by the diffracted X-rays from the sample
The X- ray detector is moved and the intensity of the diffracted X-ray reflected or transmitted from the sample is measured. (D) X-ray irradiation on the surface of the sample by the following formula 1.
The angle φ of the X-ray detector about a point is defined as
Is fixed at the position before moving, and the arbitrary axis in the sample surface is
Converted to the rotation angle α when the sample is rotated as the core
To do. [Equation 1] 2. The pole measuring method according to claim 1 , wherein
The correction value ∂ of the in-plane rotation angle β of the sample is calculated by the following equation 2.
A pole measuring method characterized by calculating β. [Equation 2] 3. The X-ray detector uses the rotation angle α converted in claim 1 and the in-plane rotation angle β + ∂β of the sample to which the correction value ∂β calculated in claim 2 is added as variables. A method for measuring a pole, wherein the intensity distribution of the diffracted X-ray is represented on a polar net.