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Research on nondestructive testing of microcracks

The traditional ultrasonic nondestructive testing technology generally needs to compare the response data of cracked components and non-destructive components, and analyze the differences between them to identify cracks. The results of the two measurements are easily affected by manual operation errors and changes in external environment, leading to false detection of cracks. Laser ultrasound has the advantages of high resolution and no need to contact the detection object directly. It has far-reaching significance for the detection of damage of materials with complex structure and expensive value. Based on the principle of excitation and reception of laser ultrasound, the detection method of micro damage on the surface of materials by laser ultrasound detection technology is studied in depth. The micro surface of materials including excitation unit, control unit and data acquisition unit is constructed.