JPH07128263A - X-ray analyzing device - Google Patents

Abstract

PURPOSE:To simultaneously execute both fluorescent X-ray analysis and X-ray diffraction analysis by providing an emitting device for emitting an X-ray containing plural kinds of characteristic X-rays mutually different in wavelength to a sample. CONSTITUTION:An X-ray tube (emitting device) 3 emits an X-ray B1 containing plural kinds of characteristic X-rays mutually different in wavelength such as RhKalpha-ray, RhKbeta-ray and RhLalpha-ray. In a sample 1 receiving the X-ray B1, the atoms are excited to generate a fluorescent X-ray B2 natural to the contained element, and the X-ray B1 is also partially diffracted as a diffracted X-ray B3 by the polycrystal of CaO. A first spectral element 4A spectrally diffracts the fluorescent X-ray B21 of the element to be measured, a second spectral element 4B spectrally diffracts the RhLalpha-ray (diffracted X-ray B3) which is a characteristic X-ray having a long wavelength. The spectrally diffracted fluorescent X-ray B21 and diffracted X-ray B3 are incident on first and second X-ray detectors 8A, 8B, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray analyzer for analyzing a sample based on fluorescent X-rays and diffracted X-rays from the sample.

[0002]

2. Description of the Related Art An X-ray fluorescence analyzer and an X-ray diffraction analyzer are both types of X-ray analyzer. An X-ray fluorescence analyzer irradiates a sample with excited X-rays and excites atoms in the sample, thereby detecting fluorescent X-rays specific to the elements contained in the sample and analyzing the composition and film thickness of the sample. It is a device to perform. On the other hand, the X-ray diffraction analyzer is an apparatus that analyzes the crystal structure of the sample by irradiating the sample with X-rays and detecting the diffracted X-rays diffracted by the crystal structure (lattice) of the sample.

[0003]

Generally, when a sample is analyzed, only one of the composition and the crystal structure of the sample is analyzed, and both the composition and the crystal structure are rarely analyzed. However, for clinker, which is a raw material for cement, it is necessary to know both the composition and the crystal structure for quality control. Therefore, it is significant to enable fluorescent X-ray analysis and X-ray diffraction analysis with one X-ray analysis device.

However, conventionally, two types of analyzes have not been performed by one device for the reason described below. The X-ray diffraction condition is given by the following Bragg equation. 2dsin θ = nλ d: Crystallographic spacing θ: Diffraction angle λ: Diffracted X-ray wavelength n: Order of reflection (1, 2, 3 ...) Here, CaO crystallographic spacing d in the clinker is , 2.40
56Å, and the wavelength λ of the X-ray B1 used is 1.5418Å (Cu
Kα line), the diffraction angle θ becomes 18.69 °. Therefore, as shown in FIG. 3A, when performing reflection type X-ray diffraction, the incident angle α (α = θ) on the sample 1 is set to a relatively small angle.

On the other hand, as shown in FIG. 3B, in the fluorescent X-ray analyzer, in order to increase the intensity of the excited X-ray B1 and the intensity of the fluorescent X-ray B2 with which the sample 1 is irradiated,
The incident angle α of the excited X-ray B1 is set to a large angle of about 90 °.

As described above, in X-ray diffraction and fluorescent X-ray analysis, since the incident angle α of the X-ray B1 incident on the sample 1 is largely different, two kinds of analyzes have been performed by one device. Absent.

It is also possible to increase the incident angle α in X-ray diffraction as shown in FIG. 3 (c). However, when this is done, transmission-type X-ray diffraction is performed in which the diffracted X-rays B3 are extracted onto the surface of the sample 1. On the other hand, the thickness of the sample 1 is generally about 2 mm to 3 mm.
Since 3 cannot be taken out, the incident angle α cannot be increased.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an X-ray analysis apparatus capable of performing both fluorescent X-ray analysis and X-ray diffraction analysis with one apparatus.

[0009]

In order to achieve the above object, the present invention provides a characteristic X-ray having a long wavelength contained in an X-ray irradiating a sample, in addition to the basic structure of a fluorescent X-ray analyzer. A spectroscopic element that disperses the characteristic X-rays diffracted and reflected by the sample and a diffractive X-ray detector that detects the characteristic X-rays having a long wavelength diffracted by the spectroscopic element are provided.

[0010]

According to the present invention, since the X-ray diffraction analysis is performed using the characteristic X-rays having a long wavelength among the characteristic X-rays, the diffraction angle becomes large. Therefore, even if X-rays are incident on the sample at a large incident angle, it is possible to extract the diffracted X-rays from the surface of the sample.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, sample 1 is a clinker as a cement raw material and contains a polycrystal of CaO. The X-ray analysis device includes an X-ray tube (irradiation device) 3, a filter device 2, first and second spectroscopic elements 4A and 4B, and first and second
Measuring instruments 5A and 5B.

The filter device 2 is provided in the vicinity of the emission window of the X-ray tube 3 and is provided with a plurality of filters 2a and 2b, a transmission window 21 and a collimator 20, as shown in FIG. Each of the filters 2a and 2b, the transmission window 21, and the collimator 20 rotate about the 0 point and are inserted into the optical path of the excitation X-ray B1 in FIG. Each of the above filters 2a, 2
b (FIG. 2) contains elements different from each other, and fluorescence X
It is used at the time of line analysis and absorbs a component of a predetermined wavelength that becomes a background in the X-ray B1. On the other hand, the collimator 20 (FIG. 2) collimates the X-ray B1 to reduce the angular spread of the X-ray B1 incident on the sample 1. First and second measuring instruments 5A, 5
B includes a fluorescent X-ray detector 8A and a diffraction X-ray detector 8B, and first and second counting circuit units 9A and 9B, respectively.

The X-ray tube 3 is arranged so as to face the surface of the sample 1. The X-ray tube 3 uses, for example, rhodium Rh as a target material, and emits X-rays B1 including a plurality of types of characteristic X-rays having different wavelengths such as RhKα rays, RhKβ rays, and RhLα rays. In the sample 1 that has received the X-ray B1, the atoms are excited to generate the fluorescent X-ray B2 peculiar to the element contained in the sample 1 and Ca
Due to the polycrystal of O, a part of the X-ray B1 is diffracted as a diffracted X-ray B3.

Both the spectroscopic elements 4A, 4B and the X-ray detectors 8A, 8B are housed in a spectroscopic chamber maintained in, for example, a vacuum atmosphere or an atmosphere of a rare gas such as helium, and all X-rays B1, B2, B21, B3 pass through such an atmosphere. Although not shown, a plurality of first spectroscopic elements 4A are provided, and the fluorescent X-rays B from the sample 1 are provided.
Of 2 and the diffracted X-ray B3, the fluorescent X-ray B21 of the element to be measured is separated. On the other hand, the second spectroscopic element 4B
Of the fluorescent X-rays B2 and diffracted X-rays B3 from the sample 1 is a characteristic X-ray with a long wavelength, that is, a RhLα ray (diffracted X-ray
3) is dispersed. These first and second spectroscopic elements 4
Fluorescent X-ray B21 and diffracted X-ray B, which are spectrally separated by A and 4B
3 is the first and second X-ray detectors 8A, 8 respectively.
It is incident on B. The extraction angle β of the diffracted X-ray B3 (RhLα ray) was calculated according to the Bragg equation from the lattice spacing d of the CaO polycrystal to be measured and the wavelength of the diffracted X-ray B3 to be detected. .69 °). For example, the incident angle α of X-ray B1 is 90
If the angle is °, the take-out angle β becomes 55.69 °.

The above-mentioned first and second X-ray detectors 8A, 8
B is the incident fluorescent X-ray B21 and the diffraction X-ray B21, respectively.
The line B3 (RhLα line) is detected, and the detection outputs e1 and e2
Is output to the first and second counting circuit units 9A and 9B. The first and second counting circuit sections 9A and 9B respectively count the detection outputs e1 and e2 to measure the intensities of the fluorescent X-ray B21 and the diffracted X-ray B3 (RhLα ray) as measurement signals x1 and x.
2 is output to the first and second arithmetic units 6A and 6B. The first and second arithmetic units 6A and 6B are respectively
Upon receiving the measurement signals x1 and x2, based on the measurement intensities of the fluorescent X-ray B21 and the diffracted X-ray B3 (RhLα ray),
The concentration of elements in the sample and the crystalline state of CaO are obtained.

Next, the analysis method will be described. First, when performing the fluorescent X-ray analysis, the filter 2a of FIG.
2b or the transmission window 21 is selected to face the emission window of the X-ray tube 3 in FIG. Next, the sample 1 is irradiated with the spread X-ray B1 from the X-ray tube 3 as an excited X-ray. X-ray B
In the sample 1 which received 1, the atoms are excited by the RhKα ray and the RhKβ ray, and the fluorescent X-ray B2 peculiar to the element is generated. The fluorescent X-rays B2 are diffracted by the first spectroscopic element 4A into the fluorescent X-rays B21 having the wavelength to be measured, and are detected by the fluorescent X-ray detector 8A, and the known fluorescent X-ray analysis is performed.
Thereby, the composition of the sample 1 is analyzed.

Next, when performing the X-ray diffraction analysis, as shown in FIG.
The collimator 20 is selected so as to face the emission window of the X-ray tube 3 in FIG. Next, from the X-ray tube 3 to the collimator 20
The sample 1 is irradiated with parallel X-rays B1 through. X-ray B1
The sample 1 that received the light emits fluorescent X-ray B2 and
The crystal lattice contained in the sample 1 diffracts the X-ray B1 in various directions. Since 2θ is set to a predetermined angle in the diffracted X-ray B3, a characteristic X-ray (for example, RhLα ray) having a predetermined wavelength is taken into consideration in relation to the crystal lattice contained in the sample 1.
Only towards the second dispersive element 4B. Of the incident fluorescent X-rays B2 and diffracted X-rays B3, the second spectroscopic element 4B follows the Bragg equation and the diffracted X-rays (RhLα rays) B
Only 3 is separated. The separated RhLα ray B3 is detected by the diffraction X-ray detector 8B, and the well-known X-ray diffraction analysis is performed. Thereby, the crystal structure of Sample 1 can be known.

As described above, since the X-ray analysis apparatus disperses the RhLα rays, which are characteristic X-rays having a long wavelength, out of the X-rays B1 emitted from the X-ray tube 3, by the second spectroscopic element 4B, As can be seen from the above Bragg equation, 2θ becomes large. Therefore, even if the incident angle α of the X-ray B1 from the X-ray tube 3 is large, the diffracted X-ray B3 (RhLα ray) can be extracted to the surface side of the sample 1. Therefore, the X-ray tube 3
X-ray diffraction analysis can be performed by using a fluorescent X-ray analyzer in which the sample is opposed to the sample 1.

By the way, X-rays having a long wavelength such as RhLα rays are absorbed by air or the like. Therefore, usually
In the case of an X-ray diffractometer that performs analysis in the atmosphere, X-ray diffraction analysis cannot be performed using long-wavelength X-rays such as RhLα rays. On the other hand, since this X-ray analyzer is a general fluorescent X-ray analyzer, the X-ray B
Since 1, B2, B3 pass through the vacuum atmosphere or the atmosphere of the rare gas, there is no possibility that RhLα rays having a long wavelength will be absorbed. Therefore, the X-ray diffraction analysis can be performed using the characteristic X-ray having a long wavelength contained in the X-ray B1.

In the above-described embodiment, the collimator 20 is provided in the filter device 2 of FIG. 2 to perform the fluorescent X-ray analysis and the X-ray diffraction analysis separately, but the collimator 20 is not always necessary.
Need not be provided. For example, when the accuracy of X-ray diffraction may be low, the X-ray B
1 does not need to be parallel light, in this case the filter 2
The fluorescent X-ray analysis and the X-ray diffraction analysis can be simultaneously performed by using a, 2b or the transmission window 21.

In the above embodiment, the characteristic X with a long wavelength is used.
Although the RhLα ray generated from the X-ray tube 3 in FIG. 1 is used as the ray, it is not always necessary to use the characteristic X-ray generated from the X-ray tube 3. For example, it is a fluorescent X-ray generated by exciting the atoms of the filters 2a and 2b of FIG. 2 with the X-ray B1 from the X-ray tube 3, and has a longer wavelength than the L-ray from the X-ray tube 3, for example, X-ray diffraction analysis may be performed using characteristic X-rays such as zirconium L-rays. In this case, the filter device 2 and the X-ray tube 3 constitute an irradiation device.

[0022]

As described above, according to the present invention, since the X-ray diffraction analysis is performed using the characteristic X-ray having the long wavelength among the characteristic X-rays, the diffraction angle becomes large. Therefore, X
Even if a ray is incident on the sample at a large incident angle, it is possible to extract the diffracted X-ray from the surface of the sample. Therefore, the fluorescent X that causes the excitation X-ray to enter the sample at a large incident angle.
X-ray diffraction analysis can be performed using a line analyzer.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an X-ray analysis apparatus showing an embodiment of the present invention.

FIG. 2 is a perspective view of a filter device.

FIG. 3 is a front view showing a relationship between an X-ray incident angle and an X-ray extraction angle.

[Explanation of symbols]

1 ... Sample, 3 ... X-ray tube, 4A ... 1st spectroscopic element, 4B ...
Second spectroscopic element, 8A ... Fluorescent X-ray detector, 8B ... Diffraction X
X-ray detector, B1 ... X-ray, B2, B21 ... Fluorescent X-ray, B3
… Diffracted X-rays.

Claims (1)

[Claims] 1. An irradiation device for irradiating a sample with X-rays including a plurality of types of characteristic X-rays having different wavelengths, a first spectroscopic element for separating fluorescent X-rays generated from the sample, and A fluorescent X-ray detector for detecting fluorescent X-rays dispersed by the spectroscopic element, and a spectral X-ray detector for separating characteristic X-rays having a long wavelength among the characteristic X-rays, which is diffracted and reflected by the sample. Two
An X-ray analysis apparatus comprising: the spectroscopic element and the diffractive X-ray detector that detects the characteristic X-ray having a long wavelength that is dispersed by the second spectroscopic element.