Hydraulic-driving mode based in situ tensile/compression testing platform under scanning electron microscope

Abstract

The invention relates to a hydraulic-driving mode based in-situ tensile / compression testing platform under a scanning electron microscope, and belongs to the field of electromechanics. The hydraulic-driving mode based in-situ tensile / compression testing platform under the scanning electron microscope comprises a hydraulic driving unit consisting of a hydraulic cylinder, an oil tank, an oil filter, a motor, a hydraulic pump, an overflow valve, a throttle valve and an electro-hydraulic servo valve, a load / displacement signal detection and control unit consisting of a displacement sensor and a pull and pressure sensor, and a clamping and supporting unit consisting of light bars, fixture body supporting racks, base linear bearings, pressure plates, a force sensor supporting rack and a specimen. The hydraulic-driving mode based in-situ tensile / compression testing platform under the scanning electron microscope has the advantages of small volume, compact structure, large output load, continuously variable transmission loading, and good structural compatibility with a microscopic imaging system with an open space structure, such as an optical microscope, a Raman spectrometer and an X-ray diffractometer and the like, and also can used for deep study on the micro-mechanical behavior and the deformation and damage mechanism of the specimen with a centimeter-level characteristic size under the action of tensile / compression loads by combination with the instruments.

Description

technical field [0001] The invention relates to the electromechanical field, in particular to an in-situ tension / compression test platform under a scanning electron microscope based on a hydraulic drive mode. It can realize the in-situ tension / compression test in the vacuum cavity of the scanning electron microscope (SEM) by means of hydraulic drive, and has open-ended functions with X-ray diffractometer, atomic force microscope (AFM), Raman spectrometer and optical microscope, etc. The instruments in the imaging environment have good structural compatibility. On the basis of testing the mechanical properties of the materials themselves, in-depth research on the crack initiation, propagation, deformation and failure mechanisms of materials under the corresponding stress or strain levels under the dynamic monitoring of the above instruments can be carried out. , providing a test method for revealing the mechanical service behavior and deformation damage mechanism of materials...

AI Technical Summary

Problems solved by technology

[0004] At the same time, in the process of mechanical testing of materials, combined with imaging instruments such as electron microscopes, X-ray diffractometers, Raman spectrometers, atomic force microscopes, or optical microscopes, the entire process of microscopic deformation, damage, and failure of materials can be dynamically monitored. It can conduct in-depth research on the micro-mechanical behavior and deformation damage mechanism of materials, and discover more novel phenomena and laws. Due to the limitation of the cavity space of imaging instruments such as scanning electron microscopes, in-situ mechanical tests in existing research mainly For micro-components, due to the existence of size effects, the mechanical properties exhibited by micro-components to characterize macroscopic materials lack certain credibility, that is, the relevant tests carried out on larger-sized specimens will be more conducive to the study of materials and their products. The real mechanical behavior and deformation damage mechanism in the service state. Further, the current in-situ tensile mechanical test under the scanning electron microscope is mainly based on the in-situ tensile test performed by a commercial torsion testing machine. System and focused ion beam and other technological methods, and the research objects are all low-dimensional materials, such as carbon nanotubes, nanowires and thin film materials, etc., lack of cross-scale in-situ mechanical tests on macroscopic dimensions (thin film materials or three-dimensional specimens), For materials with a characteristic size of centimeter or more, most of them use stepping motors combined with large reduction ratio reducers for transmission. Often the load range achieved in a specific space size is not large, so the tested pieces are mostly limited to films with a wide size. It is also difficult to study the influence of load changes on the mechanical behavior, deformation and damage mechanism of three-dimensional macroscopic materials.

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