Young modulus measurement method based on microscopic optical digital speckle method

Abstract

The invention relates to a Young modulus measurement method based on a microscopic optical digital speckle method. The method comprises the following steps: designing a microscopic optical system, setting the amplification factor of the microscopic optical system as a specific value, placing an object to be measured in the microscopic optical system, shooting and recording a gray level image before the deformation of the object to be measured, and selecting an area in the gray level image before the deformation of the object to be measured as a reference subarea, wherein the reference subareacomprises at least one speckle; shooting and recording a gray level image after the deformation of the object to be measured, and selecting an area in the gray level image after the deformation of theobject to be measured as a search subarea, and finding the area comprising the speckle in the search subarea via a search algorithm; and recording a coordinate position of the reference subarea and the coordinate position of a target subarea, and calculating a displacement amount of the target subarea relative to the reference subarea. The method provided by the invention is high in measurement precision, simple in instruments and convenient to operate.

Description

technical field [0001] The invention relates to a method for measuring Young's modulus based on a micro-optical digital speckle method, and belongs to the technical field of engineering. Background technique [0002] At present, in the field of engineering technology, the optical lever method is mostly used to measure the Young's modulus of metal materials. Usually, the optical lever and the telescope ruler set are used to measure the micro-displacement of the metal wire in the stretched state, but because this method uses an approximate relationship The formula tanα≈α, so there is a systematic error. At the same time, when the weight is increased or decreased, the weight and the weight plate will vibrate obviously and vibrate up and down, so it takes a long time to stabilize before the measurement can be carried out, which wastes a lot of experimental time; in addition In addition, the adjustment of the optical path is troublesome, the optical path is not clear, and the ope...

AI Technical Summary

Problems solved by technology

Using the dynamic resonance method to measure Young's modulus, the measurement results are stable, and the theory is very consistent with the experiment, but its disadvantages are that special instruments are required, the cost is high, and the experimental workload is large, the experimental data processing is cumbersome, and it is difficult to judge the symmetry during operation. type fundamental frequency resonance state

[0003] In view of the above analysis, the current existing methods mainly have the following problems: low measurement accuracy, easily affected by external factors; complex theoretical formulas, cumbersome experimental data processing; special instruments are required, many equipments are used, and the cost is high; It is difficult to adjust the instrument, there are many precautions, waste of experimental time, prone to deviation, affecting the stability of measurement results, etc.

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