Single-nano-thread in-situ mechanical characteristic detection and structure analysis method and apparatus

Abstract

Said invented belongs to nano material in situ characterization field. Said invented method contains putting nano line in organic solvent organic solvent, after ultrasonic dispersion 10-30 minute becoming suspension, dropping on metal grid coated with 60-120 nm collodion supporting film to make nano attached at supporting film, fixing metal grid on sample holder and putting in transmission electron microscope, measuring nano line unstretched length and diameter, adjusting transmission electron microscope beam voltage beam voltage as 80 KV to 400 KV and beam density as 20th power of 10 to 8X30th power of 10 electron / square centimeter second, to make collodion supporting film and nano line generating deformation, real time in situ recording nano line structural changes in deformation process, measuring nano line length line length and diameter after deformation, calculating nano length and diameter ratio and maximum strain quantity. Said invented has low cost and simple technology, capable of revealling one dimension nano line mechanical property from nano and atom level.

Description

Technical field: [0001] The invention relates to a method for in-situ bending and deformation of a single nanowire in a transmission electron microscope. The transmission electron microscope can be used to observe the change of the atomic structure of the deformation zone in real time, revealing the deformation mechanism of a single nanowire, and belongs to the field of in-situ characterization of nanomaterials . Background technique: [0002] With the development of nano-devices and the development of micro-mechanical systems, it is particularly urgent to study the mechanical properties of a single nanowire under external force. Transmission electron microscopy is a powerful tool for studying the microstructure of nanomaterials, but due to the small structure of nanomaterials , Difficult to manipulate, how to fix and in-situ deform a single nanowire sample in a transmission electron microscope, and reveal the deformation mechanism of a nanowire under external force from the...

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Problems solved by technology

Using this model to bend the beam beyond the critical yield point, the bending strength of carbon nanotubes and silicon carbide nanorods is also obtained. The operation process of this method is more complicated, and the measurement results are affected by human factors. Although it can be better in the elastic deformation stage of nanomaterials The elastic modulus of the nanowire or tube is measured, but when the material yields, the structural change of the nanowire during the yield process cannot be given, and the deformation mechanism cannot be fundamentally understood

[0004] The other is the experiment of stretching a single carbon nanotube using a combination of a scanning electron microscope (SEM) and an atomic force microscope. It was reported in "Science" in 2000, volume 287, pages 637-640. Two of them were installed in a scanning electron microscope. Atomic force microscope probe, two atomic force microscope probes are stretched outward and parallel to each other. They first glued the two ends of a single nanotube to the tips of the two probes, and then applied loads at both ends and examined them under the SEM. Tension observation, according to the elongation and the magnitude of the tensile force, the tensile strength of a single multi-walled carbon nanotube and single-walled carbon nanotube is obtained by calculation, and the fracture process of the elastic nanotube is observed. This method is complex and requires Reliable experimental data can only be obtained with higher experimental techniques. Although the process of stretching to fracture can be observed in situ with a scanning electron microscope, due to the limitation of the resolution of the scanning electron microscope, it is still necessary to put in a transmission tube after the nanotube is broken using this method. The electron microscope is used to observe and study its fracture behavior, but it cannot reveal its deformation mechanism in situ at the atomic level. This method is complicated and requires several different microscopic equipment to complete, which is not conducive to popularization.

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