阅读说明：本技术 单色x射线的单晶/定向晶应力测量系统和测量方法 (Monochromatic X-ray single crystal/oriented crystal stress measuring system and measuring method ) 是由 陈凯 沈昊 寇嘉伟 朱文欣 于 2019-09-19 设计创作，主要内容包括：本发明公开了一种单色X射线的单晶/定向晶应力测量系统和测量方法,测量系统中,多轴样品台包括沿X轴平移的X自由度、沿Y轴平移的Y自由度、沿Z轴平移的Z自由度、绕Z轴旋转的旋转自由度以及绕X轴和/或Y轴倾转的倾转自由度,样品台控制模块基于指令控制样品台的在其自由度上的运动,共心高调整模块基于样品表面位置发送指令到样品台控制模块使得样品表面处于共心高位置,控制单元发出指令到样品台控制模块使得处于共心高位置的样品表面旋转和倾转,以及调整X射线发生器X射线入射方向和采集模块的采集位置以采集衍射峰信号,计算模块基于衍射峰信号生成应力数据。(The invention discloses a single crystal/oriented crystal stress measuring system and a measuring method of monochromatic X-ray, in the measuring system, the multi-axis sample table comprises an X freedom degree translating along an X axis, a Y freedom degree translating along a Y axis, a Z freedom degree translating along the Z axis, a rotational freedom degree rotating around the Z axis and a tilting freedom degree tilting around the X axis and/or the Y axis, the sample table control module controls the movement of the sample table on the freedom degrees based on instructions, the concentric height adjusting module sends instructions to the sample table control module based on the position of the sample surface so that the sample surface is at a concentric high position, the control unit sends instructions to the sample table control module so that the sample surface at the concentric high position rotates and tilts, and adjusting the X-ray incidence direction of the X-ray generator and the acquisition position of the acquisition module to acquire diffraction peak signals, and generating stress data based on the diffraction peak signals by the calculation module.)

1. A monochromatic X-ray single crystal/oriented crystal stress measurement system comprises,

a multi-axis sample stage having an upper surface supporting a single crystal/oriented crystal sample, the multi-axis sample stage including an X degree of freedom to translate along an X axis, a Y degree of freedom to translate along a Y axis, a Z degree of freedom to translate along a Z axis, a rotational degree of freedom to rotate about a Z axis, and a tilt degree of freedom to tilt about an X axis and/or a Y axis,

a sample stage control module electrically connected to the multi-axis sample stage, the sample stage control module controlling movement of the sample stage in its degree of freedom based on an instruction,

a concentric height adjustment module configured to adjust a sample surface to a concentric height, the concentric height adjustment module connected to the sample stage control module including a position measurement unit to collect a sample surface position, the concentric height adjustment module sending an instruction to the sample stage control module based on the sample surface position so that the sample surface is at a concentric height position, the concentric height position being a position where the multi-axis sample stage does not change height during rotation and tilting and being a center position where the X-ray generator and the detector rotate in a plane,

an X-ray generator that generates monochromatic X-rays to irradiate the sample, the X-ray generator performing a circular motion along a circle having the concentric high position as a rotation center, an irradiation point being always located at the concentric high position when the X-ray generator rotates,

an acquisition module for receiving diffraction signals from a sample, wherein the acquisition module performs circular motion along a circle with the concentric high position as a circle center, and when the acquisition module rotates, the rotation center is always positioned at the concentric high position,

the control unit is electrically connected with the sample stage control module, the X-ray generator and the acquisition module, and based on the crystal orientation of the sample, the control unit sends an instruction to the sample stage control module to enable the surface of the sample at the concentric high position to rotate and tilt, and adjusts the X-ray incidence direction of the X-ray generator and the acquisition position of the acquisition module to acquire diffraction peak signals,

and the calculation module is connected with the acquisition module and generates stress data based on the diffraction peak signals.

2. Stress-measuring system according to claim 1, wherein, preferably, the calculation module comprises,

a fitting unit that fits based on the diffraction peak signals to obtain diffraction angle data,

a stress calculation unit that calculates a residual strain/force in a predetermined direction of the sample based on the diffraction angle,

and a stress tensor calculation unit that calculates a strain/force tensor of the sample based on the plurality of diffraction peak signals.

3. The stress-measuring system of claim 1, wherein the multi-axis sample stage comprises a multiple motion stage stack or an integral five/six degree of freedom displacement stage.

4. The stress-measuring system of claim 1, wherein the multi-axis sample stage comprises a micro-adjustable clamp for holding the sample.

5. Stress-measuring system according to claim 1, wherein the position-measuring unit comprises an optical measuring unit, a laser distance-measuring unit and/or a laser profile-acquisition unit.

6. The stress-measuring system of claim 1, wherein the acquisition module comprises a line detector or an area detector.

7. The stress-measuring system of claim 1, wherein the multi-axis sample stage comprises a coarse adjustment unit for a first accuracy of adjustment and a fine adjustment unit for a second accuracy of adjustment in a Z degree of freedom of translation along the Z axis.

8. The stress measurement system of claim 1, wherein the stress measurement system further comprises an electron back-scattering diffraction unit for measuring the crystal orientation of the sample and a calibration unit for calibrating the peak position of the diffraction peak, the calibration unit comprising alumina powder, calcium carbonate powder, and/or lithium lanthanum zirconium oxide powder.

9. A method of measuring a stress measuring system according to any of claims 1 to 8, comprising the steps of,

a first step of adjusting the sample surface to a concentric high position based on the sample surface position,

the second step, the multi-axis sample stage drives the sample surface at the concentric high position to rotate and tilt, the X-ray generator irradiates the sample surface, the acquisition module acquires the diffraction peak signal of the sample surface,

a third step of generating stress data based on the diffraction peak signal.

10. The measurement method according to claim 9, wherein, in the second step, at the time of the first diffraction peak signal acquisition, the stage control module controls the multi-axis stage to rotate around the Z-axis while the acquisition module acquires, stops rotating when the diffraction peak signal is acquired to be higher than a predetermined threshold value, and starts swinging within a predetermined angle range, and performs tilting in a predetermined step per predetermined angle while the acquisition module performs acquisition, and the third step is repeatedly performed to acquire a predetermined number of diffraction peak signals, and generates stress data and a stress tensor based on the diffraction peak signals.

Technical Field

The invention belongs to the technical field of single crystal measurement, and particularly relates to a single crystal/oriented crystal stress measurement system and a measurement method of monochromatic X-rays.

Background

The single crystal blade is used as a key part in a gas turbine and an aircraft engine, and has excellent mechanical property, high-temperature creep resistance and oxidation resistance. Some residual stress is inevitably generated in the processing and production process of the single crystal blade, and the existence of the residual stress influences the service life of the blade. In addition, during the service process, due to the use under long-term extreme working conditions or the impact of foreign objects such as dust particles and the like, residual stress is generated on the blade, so that cracks are generated, and failure are caused. At present, laser shock peening is used as a treatment process of a blade, residual stress is introduced on the surface of the blade, the fatigue life and the shock resistance of the blade in service are greatly improved, and the residual stress introduced after the laser shock peening is particularly large, so that the blade life is favorable in what range, and the residual stress measurement value is needed to support. Therefore, the measurement of the residual stress of the single crystal blade is very important for the evaluation of the blade before and after service and the treatment process.

At present, the mode used for nondestructive residual stress detection in a laboratory is also a mode based on a powder sample or a polycrystalline sample, and the mode is not suitable for a single crystal sample or an oriented crystal sample. The measurement of residual stress of single crystals and oriented crystals is currently performed by means of large scientific devices, such as synchrotron radiation X-ray and neutron diffraction. Rely on big scientific equipment to realize high accuracy and even high spatial resolution's measurement, however the available machine of big scientific equipment is limited in the time, can not satisfy the purpose of producing at any time and measuring at any time, and the data bulk that big scientific equipment gathered is very huge, often has the multilayer meaning moreover, and the data analysis degree of difficulty is great, is not practical in engineering in-service use.

Therefore, in light of the above practical needs and the shortcomings of the prior art, we will purposely propose a single crystal/oriented crystal stress measurement system and measurement method using monochromatic X-rays of conventional laboratory energy level to achieve efficient, fast and automatic precision measurement.

The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a single crystal/oriented crystal stress measuring system and a single crystal/oriented crystal stress measuring method of monochromatic X rays, which simplify the detection requirement and can conveniently and precisely measure and obtain the residual stress and the stress tensor of the single crystal in an automatic way only by using low laboratory energy level monochromatic X rays.

The invention aims to realize the purpose by the following technical scheme, and the single crystal/oriented crystal stress measuring system of the monochromatic X-ray comprises:

a multi-axis sample stage having an upper surface supporting a single crystal/oriented crystal sample, the multi-axis sample stage including an X degree of freedom to translate along an X axis, a Y degree of freedom to translate along a Y axis, a Z degree of freedom to translate along a Z axis, a rotational degree of freedom to rotate about a Z axis, and a tilt degree of freedom to tilt about an X axis and/or a Y axis,

a sample stage control module electrically connected to the multi-axis sample stage, the sample stage control module controlling movement of the sample stage in its degree of freedom based on an instruction,

a concentric height adjustment module configured to adjust a sample surface to a concentric height, the concentric height adjustment module connected to the sample stage control module including a position measurement unit to collect a sample surface position, the concentric height adjustment module sending an instruction to the sample stage control module based on the sample surface position so that the sample surface is at a concentric height position, the concentric height position being a position where the multi-axis sample stage does not change height during rotation and tilting and being a center position where the X-ray generator and the detector rotate in a plane,

an X-ray generator that generates monochromatic X-rays to irradiate the sample, the X-ray generator performing a circular motion along a circle having the concentric high position as a rotation center, an irradiation point being always located at the concentric high position when the X-ray generator rotates,

an acquisition module for receiving diffraction signals from a sample, wherein the acquisition module performs circular motion along a circle with the concentric high position as a circle center, and when the acquisition module rotates, the rotation center is always positioned at the concentric high position,

the control unit is electrically connected with the sample stage control module, the X-ray generator and the acquisition module, and based on the crystal orientation of the sample, the control unit sends an instruction to the sample stage control module to enable the surface of the sample at the concentric high position to rotate and tilt, and adjusts the X-ray incidence direction of the X-ray generator and the acquisition position of the acquisition module to acquire diffraction peak signals,

and the calculation module is connected with the acquisition module and generates stress data based on the diffraction peak signals.

In the stress measurement system, the calculation module comprises,

a fitting unit that fits based on the diffraction peak signals to obtain diffraction angle data,

a stress calculation unit that calculates a residual strain/force in a predetermined direction of the sample based on the diffraction angle,

and a stress tensor calculation unit that calculates a strain/force tensor of the sample based on the plurality of diffraction peak signals.

In the stress measurement system, the multi-axis sample table comprises a plurality of motion table stacking structures or an integrated five/six-degree-of-freedom displacement table.

In the stress measurement system, the multi-axis sample stage comprises a clamp which is used for fixing a sample and can carry out micro adjustment on the position of the sample.

In the stress measuring system, the position measuring unit comprises an optical measuring unit, a laser ranging unit and/or a laser profile collecting unit.

In the stress measurement system, the acquisition module comprises a line detector or an area detector.

In the stress measurement system, the multi-axis sample table comprises a coarse adjustment unit with first adjustment precision and a fine adjustment unit with second adjustment precision in the Z degree of freedom of translation along the Z axis.

In the stress measuring system, the stress measuring system further comprises an electron back scattering diffraction unit for measuring the crystal orientation of the sample and a calibration unit for calibrating the peak position of the diffraction peak, wherein the calibration unit comprises alumina powder, calcium carbonate powder and/or lithium lanthanum zirconium oxygen powder.

According to another aspect of the present invention, a measuring method of the stress measuring system includes the steps of,

a first step of adjusting the sample surface to a concentric high position based on the sample surface position,

the second step, the multi-axis sample stage drives the sample surface at the concentric high position to rotate and tilt, the X-ray generator irradiates the sample surface, the acquisition module acquires the diffraction peak signal of the sample surface,

a third step of generating stress data based on the diffraction peak signal.

In the measuring method, in the second step, when a first diffraction peak signal is collected, the sample stage control module controls the multi-axis sample stage to rotate around the Z axis, the collection module collects the first diffraction peak signal, when the collected diffraction peak signal is higher than a preset threshold value, the multi-axis sample stage stops rotating and starts swinging within a preset angle range, every time the multi-axis sample stage rotates by a preset angle step, the pre-set step is tilted, the collection module collects the first diffraction peak signal at the same time, the pre-set number of diffraction peak signals are collected by repeated execution, and in the third step, stress data and stress tensor are generated based on the diffraction peak signals.

Compared with the prior art, the invention has the following advantages:

according to the invention, the height of the single crystal sample is adjusted based on the determined crystal orientation of the single crystal sample, so that the surface of the single crystal sample is positioned at the concentric high position, wherein the concentric high position is a position where the height of an observation point is not changed in the tilting process of the single crystal sample, and the detection precision is ensured; adjusting the incidence direction of monochromatic X-rays and the relative position of a detector for obtaining diffraction signals and a single crystal sample to obtain diffraction signals; and obtaining the strongest position of the diffraction peak based on the diffraction signal, calculating the residual stress and stress tensor of the single crystal sample based on the diffraction peak at the position, simplifying the detection requirement, conveniently detecting the residual stress of the single crystal in a large batch without X rays, synchrotron radiation and neutron diffraction with high energy level.

Drawings

Various other advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. It is obvious that the drawings described below are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. Also, like parts are designated by like reference numerals throughout the drawings.

In the drawings:

FIG. 1 is a schematic diagram of a monochromatic X-ray single crystal/directional crystal stress measurement system according to one embodiment of the present invention;

FIG. 2 is a schematic structural diagram of the steps of a measurement method of a monochromatic X-ray single crystal/oriented crystal stress measurement system according to an embodiment of the invention.

The invention is further explained below with reference to the figures and examples.

Detailed Description

Specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While specific embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

It should be noted that certain terms are used throughout the description and claims to refer to particular components. As one skilled in the art will appreciate, various names may be used to refer to a component. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The description which follows is a preferred embodiment of the invention, but is made for the purpose of illustrating the general principles of the invention and not for the purpose of limiting the scope of the invention. The scope of the present invention is defined by the appended claims.

For the purpose of facilitating understanding of the embodiments of the present invention, the following description will be made by taking specific embodiments as examples with reference to the accompanying drawings, and the drawings are not to be construed as limiting the embodiments of the present invention.

For a better understanding, as shown in fig. 1, a monochromatic X-ray single crystal/directional crystal stress measurement system includes,

a multi-axis sample stage 1, an upper surface of which supports a single crystal/oriented crystal sample, the multi-axis sample stage 1 including an X degree of freedom to translate along an X axis, a Y degree of freedom to translate along a Y axis, a Z degree of freedom to translate along a Z axis, a rotational degree of freedom to rotate about the Z axis, and a tilting degree of freedom to tilt about the X axis and/or the Y axis,

a sample stage control module 2 electrically connected to the multi-axis sample stage 1, the sample stage control module 2 controlling the movement of the sample stage in the degree of freedom thereof based on an instruction,

a concentric height adjustment module 3 configured to adjust a sample surface to a concentric height, the concentric height adjustment module 3 connected to the sample stage control module 2 including a position measurement unit that acquires a position of the sample surface, the concentric height adjustment module 3 sending an instruction to the sample stage control module 2 based on the sample surface position so that the sample surface is at a concentric height position, which is a position where the height of the multi-axis sample stage 1 does not change during rotation and tilting and which is a center position where the X-ray generator 4 and the detector rotate in a plane,

an X-ray generator 4 that generates monochromatic X-rays to irradiate the sample, the X-ray generator 4 performing a circular motion along a circle having the concentric high position as a rotation center, when the X-ray generator 4 rotates, an irradiation point is always located at the concentric high position,

an acquisition module 5 for receiving diffraction signals from the sample, wherein the acquisition module 5 performs circular motion along a circle with the concentric high position as a circle center, when the acquisition module 5 rotates, the rotation center is always positioned at the concentric high position,

a control unit 6 electrically connected to the stage control module 2, the X-ray generator 4 and the acquisition module 5, the control unit 6 giving an instruction to the stage control module 2 to rotate and tilt the surface of the sample at the concentric high position based on the crystal orientation of the sample, and adjusting the X-ray incidence direction of the X-ray generator 4 and the acquisition position of the acquisition module 5 to acquire a diffraction peak signal,

and the calculation module 7 is connected with the acquisition module 5, and the calculation module 7 generates stress data based on the diffraction peak signals.

The single crystal/oriented crystal measurement system of the monochromatic X-ray realizes efficient, quick and automatic precise measurement of the residual stress in the single crystal/oriented crystal sample.

In one embodiment, the measurement system comprises a calculation module 7, a concentric height adjustment module 3, a sample stage control module 2, an X-ray generation and acquisition module 5, a multi-axis sample stage 1 and a control unit 6. The control unit 6 obtains the diffraction peaks of possible crystal planes according to the approximate crystal orientation and the Bragg equation, so as to adjust the X-ray incidence direction of the X-ray generation and acquisition module 5 and the approximate acquisition position of the detector. The height direction of the multi-axis sample table 1 is controlled by the sample table control module 2, and the concentric height adjusting module 3 is combined, so that the sample surface fixed by the sample clamp is adjusted to the concentric height. In the signal acquisition process, the rotation and tilting functions of the multi-axis sample stage 1 are controlled by the sample stage control module 2, so that the peak searching process is realized. Finally, the acquired diffraction peak signals are subjected to peak shape fitting in a calculation module 7 to obtain an accurate diffraction angle, so that the stress is calculated.

In a preferred embodiment, wherein the general orientation of the crystals need only be known, it can be determined by the production, processing or fabrication process of the sample, or by Electron Back Scattering Diffraction (EBSD).

In a preferred embodiment, the concentric height is the position where the sample observation point does not change height during rotation and tilting, and is also the position where the X-ray generator 4 and the detector rotate in the plane. The change of the position of the observation point is moved in the plane by the X and Y displacement stages.

In a preferred embodiment, the concentric height adjustment module 3 comprises a height detector, and the height measurement may be performed by using an optical low-depth-of-field lens, laser ranging, or laser profile acquisition. The sample stage control module 2 can adjust the surface height of the sample according to the height information collected by the concentric height adjusting module 3, or adjust the height and the inclination of a specific point according to the collected contour information.

In a preferred embodiment, the multi-axis sample stage 1 has five or six dimensions, including in-plane movement (X-axis, Y-axis), height-direction translation (Z-axis), in-plane rotation (about Z-axis), and tilt around axis (which may include about X-axis and about Y-axis). The adjustment of the sample stage in the height direction can be divided into Z-axis coarse adjustment and Z-axis fine adjustment. The multi-dimensional sample table can be built in a mode that a plurality of motion tables are stacked, and can also be a combination of an integrated hexapod displacement table and a necessary expansion table.

In a preferred embodiment, the calculation module 7 is in communication with the X-ray generation and acquisition module 5 and the stage control module 2. The calculation module 7 provides the crystal planes likely to produce diffraction peaks and the corresponding diffraction angles and positions of the diffraction peaks in space. The X-ray generation and acquisition module 5 rotates the X-ray generator 4 and the detector to corresponding positions around a concentric point according to the result provided by the calculation module 7. The sample stage control module 2 rotates and tilts the sample within a set angle range according to the result provided by the calculation module 7. The acquisition of the X-ray diffraction signal can be performed while rotating and tilting.

In a preferred embodiment, the detector may be a line detector, or a plane detector.

In a preferred embodiment, wherein the stress calculation module 7 includes a peak shape fit and a peak position calibration, the calibration includes using alumina powder, calcium carbonate powder, and lithium lanthanum zirconium oxide powder.

To further understand the present invention, in the embodiment, a single crystal nickel-based alloy sample with <001> orientation is fixed on a sample stage by a clamp, the <001> direction is substantially along the Z direction as shown in the figure, and the concentric height adjusting module 3 adjusts the position to be measured to the concentric height position. The calculation module 7 calculates the crystal face and the corresponding diffraction angle which can generate diffraction signals in a high angle range such as (130 degrees to 165 degrees), the X-ray generation and acquisition module 5 records the corresponding diffraction angle, when the first diffraction peak is acquired, the sample stage control module 2 starts to control the sample stage to rotate around the Z axis, the detector acquires signals at the same time, when the acquired diffraction signals are higher than the background signals by a certain threshold value, the sample stage control module stops rotating (about 20 percent), and starts to swing (including rotating and tilting directions) in the range of +/-10 degrees of the position, tilting is performed by 0.1 degree every time, data acquisition is performed, and at the same time, tilting is also performed according to a certain step length (0.1 degree), and the diffraction signals of each movement are recorded. According to the recorded data, a two-dimensional diffraction peak distribution cloud picture is made, and the residual stress is calculated in the stress calculation module 7 according to the calibration result. After the peak searching of the diffraction peak and the residual stress calculation are finished, the peak searching, calibration and calculation processes of the next diffraction peak are automatically carried out. After 6 diffraction peaks are collected and calculated, the stress tensor can be obtained.

In the preferred embodiment of the stress-measuring system described, the calculation module 7 comprises,

a fitting unit 8 that fits based on the diffraction peak signals to obtain diffraction angle data,

a stress calculation unit 9 that calculates a residual stress of the sample based on the diffraction angle,

and a stress tensor calculation unit that calculates a stress tensor of the sample based on the plurality of diffraction peak signals.

In the preferred embodiment of the stress measuring system, the multi-axis sample stage 1 comprises a plurality of motion stage stacked structures or an integrated six-degree-of-freedom displacement stage.

In the preferred embodiment of the stress measurement system described, the multi-axis sample stage 1 includes a clamp for holding the sample that allows fine adjustment of the position of the sample.

In a preferred embodiment of the stress measuring system, the position measuring unit comprises an optical measuring unit, a laser ranging unit and/or a laser profile acquisition unit.

In a preferred embodiment of the stress-measuring system described, the acquisition module 5 comprises a line detector or an area detector.

In the preferred embodiment of the stress measuring system, the multi-axis sample stage 1 comprises a coarse adjusting unit with first adjusting precision and a fine adjusting unit with second adjusting precision in the Z degree of freedom of translation along the Z axis.

In a preferred embodiment of the stress measuring system, the stress measuring system further comprises an electron back-scattering diffraction unit for measuring the crystal orientation of the sample and a calibration unit for calibrating the peak position of the diffraction peak, the calibration unit comprising alumina powder, calcium carbonate powder and/or lithium lanthanum zirconium oxide powder.

In a preferred embodiment of the stress measurement system, the stage control module 2, the control unit 6 and/or the calculation module 7 comprise a storage unit for storing data, a digital signal processor for processing data and drawing, an application specific integrated circuit ASIC or a field programmable gate array FPGA, and the storage unit comprises one or more of a ROM, a RAM, a flash memory or an EEPROM.

In the preferred embodiment of the stress measurement system, the sample stage control module 2, the control unit 6 and/or the calculation module 7 are connected with the mobile terminal through a data line, and the mobile terminal comprises a computer, a mobile phone, a bracelet, a large screen and a cloud server.

As shown in fig. 2, a measuring method of the stress measuring system includes the following steps,

a first step S1 of adjusting the sample surface to a concentric high position based on the sample surface position,

in the second step S2, the multi-axis sample stage 1 rotates and tilts the sample surface at the concentric high position, the X-ray generator 4 irradiates the sample surface, the collection module 5 collects the diffraction peak signal of the sample surface,

a third step S3 of generating stress data based on the diffraction peak signal.

In a preferred embodiment of the measuring method, in the second step S2, when the first diffraction peak signal is collected, the multi-axis sample stage 1 is controlled by the sample stage control module 2 to rotate around the Z axis, and the collection module 5 collects the first diffraction peak signal, and when the collected diffraction peak signal is higher than a predetermined threshold, the multi-axis sample stage stops rotating, and starts swinging within a predetermined angle range, and when the collected diffraction peak signal is higher than the predetermined threshold, the collection module 5 performs tilting with a predetermined step length every 0.1 degree of rotation, and performs collection while repeating the collection to collect a predetermined number of diffraction peak signals, and the third step S3 generates stress data and stress tensor based on the diffraction peak signals.

In the preferred embodiment of the measuring method, the incident direction of monochromatic X-rays and the relative position of the detector for obtaining diffraction signals and the single crystal sample can be adjusted by controlling the X-ray generator 4 in a tilting manner, so that the X-rays are deflected in a predetermined step within a predetermined angle range in the plane of the X-ray generator 4 and the detector to realize the change of the incident angle, after each movement of the X-rays by an angle of the predetermined step, the sample stage is rotated, and simultaneously the detector records diffraction signals during the rotation of the sample stage.

In the preferred embodiment of the measuring method, the incident direction of monochromatic X-rays and the relative position of a detector for obtaining diffraction signals and a single crystal sample are adjusted, the inclined angle between the plane of the single crystal sample and the horizontal plane is changed by controlling the tilting angle of a sample stage for rotating the single crystal sample, so that the sample stage can be tilted within the angle range meeting the diffraction conditions, the height of a sample observation point is unchanged, and after the sample stage is tilted by the angle of the preset step length, the sample stage is rotated and the detector records the diffraction signals.

In the preferred embodiment of the measuring method, the crystal sample obtains a corresponding crystal face through a rotatable sample stage and a detected diffraction angle, another crystal orientation is obtained through obtaining the position of a diffraction signal, orientation information of the single crystal sample in a three-dimensional space is obtained through the two crystal orientations, the degrees of freedom of the sample stage for rotating the single crystal sample comprise a tilting degree of freedom around an axis and a rotating degree of freedom, the degree of freedom of an X-ray generator 4 is the degree of freedom of swinging in the plane of the X-ray generator 4 and a detector, and the center of the swinging circle is a concentric point.

In the preferred embodiment of the measuring method, the X-ray generator 4 and the detector rotate to corresponding positions around a concentric point, and the sample stage control module 2 rotates and tilts the sample within a set angle range according to the result provided by the calculation module 7. The acquisition of the X-ray diffraction signal can be performed while rotating and tilting.

In the preferred embodiment of the measuring method, in the peak searching process, the diffraction peak is firstly identified, the approximate position of the diffraction peak is obtained, and then the rotating and tilting angle is changed to carry out fixed-step acquisition in a certain range.

The invention can realize high-efficiency, quick and automatic precision measurement of the residual stress of the single crystal and the oriented crystal by utilizing monochromatic X-rays in a conventional laboratory.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments and application fields, and the above-described embodiments are illustrative, instructive, and not restrictive. Those skilled in the art, having the benefit of this disclosure, may effect numerous modifications thereto without departing from the scope of the invention as defined by the appended claims.