Nondestructive testing method and equipment for elastic constants based on laser ultrasound

Abstract

The invention relates to a nondestructive testing method and equipment for elastic constants based on laser ultrasound. The method comprises the following steps of: focusing pulse laser light and acting the pulse laser light on an excitation point on the front surface of a material to be detected to generate ultrasonic waves; irradiating exploring laser light on a receiving point on the front surface of the material to be detected, and generating a Doppler effect and an interference phenomenon by reflected light to obtain a surface wave signal; displaying and storing a fluctuation image of thesurface wave signal changing with time by detecting a time origin of an ultrasonic signal provided by a pulsed laser signal on the surface of a sample; irradiating exploring laser light on a receiving point on the reverse side of the material to be detected, and generating a Doppler effect and an interference phenomenon by reflected light to obtain a longitudinal wave signal; displaying and storing a fluctuation image of the longitudinal wave signal changing with time; and calculating an elastic constant of the material to be detected according to a solid mechanics formula. According to the method provided by the invention, ultrasonic waves are excited by adopting laser ultrasound, so that longitudinal waves, transverse waves and surface waves can be simultaneously generated at one time,blind area-free measurement of ultrasonic waves of materials with same properties can be realized, and the precision of measuring the elastic constant is high.

Description

technical field [0001] The invention relates to the technical field of detection of elastic constants of materials, in particular to a method and equipment for nondestructive detection of elastic constants based on laser ultrasound. Background technique [0002] The traditional elastic constant detection and inspection methods of materials mainly include tensile test method, indentation hardness method and ray inspection method, but these methods generally have relatively low efficiency, relatively narrow scope of application, and qualitative and quantitative analysis of material and workpiece defects. The characterization accuracy cannot meet the high-precision engineering requirements. Tensile test method and indentation hardness method belong to destructive testing, which will bring performance damage to the test piece; radiographic testing needs to consider radiation safety protection issues, protect the health and safety of operators, and have high requirements for film...

AI Technical Summary

Problems solved by technology

[0003] The present invention aims to provide a non-destructive testing method and equipment based on laser ultrasonic elastic constants, aiming to solve the problem that traditional non-destructive testing methods and equipment have low detection accuracy and efficiency, are not suitable for complex shapes, and are not suitable for high temperature, corrosion and radiation. The isotropic material elastic constant test environment and other issues

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