Noise reduction method for ultrasonic detection signal of metal internal defect

Abstract

The invention discloses a noise reduction method for ultrasonic detection signals of metal internal defects, and relates to the technical field of ultrasonic nondestructive detection. According to the method, the technical problem that an existing noise reduction method for ultrasonic detection signals does not depend on a self forming mechanism is solved; according to the technical scheme, the idea of hierarchical threshold processing is introduced into a CEEMDAN algorithm, thereby providing the threshold noise reduction method for the ultrasonic detection signal based on the CEEMDAN algorithm and the spatial correlation; the problem that a traditional noise reduction method is separated from an ultrasonic detection signal forming mechanism is solved, and the method has higher adaptability, effectiveness and stability. meanwhile, the spatial correlation coefficient of the ultrasonic detection signal subjected to threshold value processing is set as a reconstruction coefficient of each mode, the mechanism that defect echo spatial correlation is high and noise component spatial correlation is low is fully utilized, echo signals in ultrasonic detection signals are reserved, noise components are inhibited, and an ideal noise reduction effect is obtained.

Description

technical field [0001] The present disclosure relates to the technical field of ultrasonic nondestructive testing, and in particular to a noise reduction method for ultrasonic testing signals of internal metal defects. Background technique [0002] Metal materials have a series of excellent properties and are widely used in high-end fields such as aerospace, nuclear industry and national defense. Various internal defects will be formed during the processing of metal materials, which will lead to the decline of material performance, which will lead to component failure and equipment failure, which will affect the safety and reliability of equipment. Metal material non-destructive testing technology is of great significance to ensure the safety and reliability of equipment. Ultrasonic non-destructive testing technology has the advantages of simple equipment, good safety, wide detection range and high sensitivity, and is widely used in the field of industrial equipment testing....

AI Technical Summary

Problems solved by technology

The sparse decomposition method also has inherent limitations. When the basis functions in the over-complete dictionary do not strictly satisfy the orthogonality, or the signal-to-noise ratio of the signal is very low, it is difficult to obtain an effective sparse decomposition result.

[0004] The current noise reduction methods seldom treat the noise in the ultrasonic detection signal as ordinary random noise by default from the perspective of the principle of ultrasonic detection. This simple processing often cannot obtain effective noise reduction effects.

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