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CN-122016882-A - Multi-field temperature-adjustable in-situ mechanical loading and X-ray imaging method and device

CN122016882ACN 122016882 ACN122016882 ACN 122016882ACN-122016882-A

Abstract

The invention provides a multi-field temperature-adjustable in-situ mechanical loading and X-ray imaging device and method, and belongs to the technical field of high-temperature in-situ mechanical property testing and material structure imaging. The device comprises a mechanical loading unit, a clamp unit, a high-temperature furnace, a heating unit, an atmosphere control system, a cylindrical X-ray transmission window and an imaging system. The heating unit can be used for adjusting axial and angle degrees of freedom, and is matched with multipoint temperature feedback to form closed-loop control, so that a temperature field with high uniformity or programmable gradient is realized. The atmosphere system supports the environment switching of high-purity inert gas, low oxygen partial pressure, high vacuum and the like. The method comprises sample clamping, heat source type selection, temperature zone adjustment, loading program setting, atmosphere environment regulation and control, in-situ imaging data acquisition and analysis. The invention is suitable for researching the force-heat-environment coupling behavior of various materials such as ceramic matrix composite materials, high-temperature alloys and the like under the extreme service condition.

Inventors

  • XI LI
  • WANG YAN

Assignees

  • 北京理工大学

Dates

Publication Date
20260512
Application Date
20260224

Claims (10)

  1. 1. A multi-field temperature-adjustable in-situ mechanical loading and X-ray imaging device, comprising: The mechanical loading unit is used for applying a single-axis or multi-axis controllable loading force to the sample; The clamp unit is arranged between the mechanical loading unit and the sample and used for fixing the sample and transmitting loading force to the sample, and comprises an upper clamping piece, a lower clamping piece, an upward-pulling compression bar and a downward-pulling compression bar which are connected with the mechanical loading unit; A high temperature furnace comprising an upper furnace body, a cylindrical X-ray transmission window and a lower furnace body, forming a sealed furnace chamber and surrounding the sample; the heating unit is arranged on the inner wall of the furnace body of the high-temperature furnace through a mounting seat and is coaxially arranged with the clamp unit, an annular fixed flange is arranged on the mounting seat through a rotating rod, an annular movable flange is arranged between the mounting seat and the annular fixed flange, and the annular movable flange realizes the adjustable positioning of the heating unit in the axial direction and the angle through the rotating rod, a knob and a spring; the atmosphere control system is connected with the furnace chamber of the high-temperature furnace and is used for switching and steady-state control among high-purity inert gas, low-oxygen partial pressure or vacuum environments; An imaging system comprising an X-ray source and a detector arranged opposite the cylindrical X-ray transmission window; and the control console is used for synchronously controlling and collecting data of the mechanical loading unit, the heating unit, the atmosphere control system and the imaging system.
  2. 2. The device according to claim 1, wherein the annular moving flange is nested with the annular fixed flange by a high temperature wear bearing, and the spring is a compression spring acting between the annular moving flange and the annular fixed flange to ensure stable positioning of the heating unit in high temperature environments.
  3. 3. The apparatus of claim 1, wherein the cylindrical X-ray transmissive window is of a low absorption high strength alloy or high temperature ceramic material and has a thickness and diameter that meet high transmittance, gas tightness and structural strength requirements at the same time and is centered on the imaging optical path to reduce diffraction artifacts.
  4. 4. The apparatus of claim 1, wherein the atmosphere control system comprises a separate air intake unit, exhaust unit, gas circulation line, and vacuum pumping device to maintain stability of the furnace chamber atmosphere of the furnace while loading and imaging are operated simultaneously.
  5. 5. The apparatus of claim 1, wherein the heating unit is a halogen lamp heating unit or a fiber laser heating unit, the halogen lamp heating unit comprises a halogen lamp and a hemispherical high-reflectivity lampshade, the power and the quantity of the halogen lamp can be independently adjusted, the lampshade is aligned to the central area of the sample, the fiber laser heating unit comprises a fiber terminal, a collimating lens, a reflecting mirror and a focusing lens module, and the output light spot is focused on the surface of the sample after being adjusted in position and angle.
  6. 6. A method of in-situ mechanical loading and X-ray imaging testing of a temperature-adjustable zone multi-field environment based on the apparatus of claims 1 to 5, comprising the steps of: the method comprises the steps of firstly, fixing a sample on a clamp unit, and coaxially connecting the sample with a mechanical loading unit; adjusting the positions and angles of the mounting seat and the annular moving flange so as to enable the thermal focus of the heating unit to be aligned with the target area of the sample; thirdly, setting a working mode and target parameters of an atmosphere control system, and adjusting the atmosphere of the furnace chamber to be a target environment and stabilizing; starting a heating unit and heating the sample to a target temperature range according to a preset heating rate; Fifthly, starting a mechanical loading unit in the heating process or after the heating is finished, and applying mechanical load to the sample according to a preset loading program; Sixthly, projecting X-rays through a cylindrical X-ray transmission window, and acquiring dynamic transmission images or CT fault data by a detector; and seventhly, transmitting the acquired load, displacement, temperature and imaging data to a console for storage and analysis.
  7. 7. The method of claim 6, wherein the heating unit in the second step is adjusted to have an axial direction of + -10 mm and an angle of + -5 DEG, and the temperature distribution of the furnace chamber is monitored by a multi-point temperature sensor, and the heating power is adjusted in real time by closed loop control.
  8. 8. The method of claim 6, wherein the atmosphere control mode in the third step is selected from the group consisting of high purity inert gas, low oxygen partial pressure, and high vacuum environment to simulate material behavior under different service conditions.
  9. 9. The method of claim 6, wherein the imaging procedure acquisition rate in the sixth step is not less than 10Hz and the imaging path length is minimized using the flat furnace structure of the device and the cylindrical X-ray transmissive window design.
  10. 10. The method of claim 6, wherein the seventh step includes coupling analysis of the obtained temperature field with the stress field using a finite element method to assist in interpreting imaging results and material failure mechanisms.

Description

Multi-field temperature-adjustable in-situ mechanical loading and X-ray imaging method and device Technical Field The invention belongs to the technical field of analysis of material components or structures and measurement of mechanical properties of solid substances, and particularly relates to a high-temperature in-situ mechanical loading and X-ray imaging test method and device with a temperature-adjustable region, multi-heat source exchange capability and multi-field environment control function. Background The high-temperature in-situ mechanical loading and structural imaging technology is an important means for researching the mechanical behavior and failure mechanism of advanced structural materials, especially ceramic matrix composite materials, high-temperature alloys and carbon matrix materials, in an extreme service environment. With the increase of research requirements of service reliability of materials in high-temperature, high-load and multi-field coupling states in the fields of aerospace, energy power and the like, higher requirements are put forward on integration and expandability of a high-temperature furnace-mechanical loading-imaging system on a laboratory and a large-scale scientific device platform. Early high temperature in situ test devices relied on resistive wires or fixed halogen lamps as a single heat source, combined with simple vacuum or inert gas environments for mechanical loading and optical imaging. The scheme has a compact structure, is suitable for basic high-temperature stretching or compression tests, but has uneven thermal field distribution and limited temperature area regulation and control range, and cannot meet the fine requirements on temperature gradient or local heating. Meanwhile, the imaging channel is designed by adopting a plane window, so that thermal stress is easy to generate under the high-temperature condition to cause the transmissivity to be reduced, and the observation precision is affected. Subsequently, with the rise of synchrotron radiation light sources, the second stage of technical development focused on integrated systems of high resolution X-ray imaging platforms. The devices tightly combine the mechanical loading unit with the high-temperature furnace chamber, and realize real-time dynamic imaging by utilizing a high-brightness X-ray source. Entering the third stage, some compact laboratory-level devices began to introduce modular elements, such as replaceable heating elements and improved atmosphere interfaces, but the whole was still limited to a single heat source type and basic environmental control. In the prior art, the problems of single and fixed heat source form, difficulty in optimizing key indexes such as heating rate, temperature uniformity, local regulation precision and the like aiming at different material characteristics due to lack of a unified interface and modularized exchange design mainly exist in the prior art, the atmosphere control means are limited, most devices can only provide inert atmosphere or high vacuum, regulation and control capability on key environmental conditions such as low oxygen partial pressure and the like are insufficient, in-situ test requirements of high-temperature oxidation/corrosion sensitive materials cannot be met, and the imaging window design does not consider both high-temperature strength and radiation transmittance and is easy to produce in extreme environments The existing deformation or absorption is enhanced, the imaging quality is directly affected, and the fourth part of the device has large volume and high weight, cannot meet the installation space constraint of a high-flux platform or laboratory conventional equipment, and increases the use and maintenance cost. Therefore, a high-temperature in-situ mechanical loading and imaging device and method which can realize the interchangeable use of multiple heat sources under the same furnace body and control interface while maintaining a compact structure, and have the advantages of adjustable temperature area, atmosphere diversified control, imaging path optimization and rapid deployment capability are urgently needed, so that the limitations of the prior art in environmental adaptability, thermal field control precision and test suitability are overcome. This is also the technical problem and the innovative direction to be solved by the present invention. Disclosure of Invention The existing high-temperature in-situ loading and imaging device has various limitations. Most of the existing devices only can use a single type of heat source, most of the heat sources are fixedly installed, atmosphere control capability is limited, most of imaging window designs do not find the best balance between high-temperature atmosphere bearable capacity and X-ray transmittance, so that transmittance attenuation is obvious under extreme conditions, imaging signal quality is reduced, most of high-temperature loading systems are large in size and h