A Shape Reconstruction Method for Subsurface Defects in Thermal Imaging Inspection

Abstract

The invention discloses a sub-surface defect shape reconstruction method in thermal imaging detection, which is divided into the acquisition process of thermal response signals, the phase difference solution process between defective areas and non-defective areas, and the use of envelopes to reconstruct defect shapes The process has three parts. Use a line heat source to scan the test piece, and then perform Fourier analysis on the data collected at the location of the heating source to find the phase difference corresponding to other positions and no defects, and invert the depth of the defect according to the phase difference, and then according to each The result of the position line scanning is the obtained depth to make the envelope, and finally estimate the shape of the defect according to the envelope. The invention is capable of estimating and reconstructing the shapes of irregular defects, which is beneficial to the quantitative evaluation of defects, and solves the problem of quantitative analysis of such defects when surface excitation is adopted.

Description

technical field [0001] The invention belongs to the technical field of non-destructive testing of specimens containing subsurface defects, and more specifically relates to a shape reconstruction method for subsurface defects in thermal imaging testing. Background technique [0002] With the continuous development of science and technology, the quality and safety of mechanical equipment or components has become an issue of increasing concern. Infrared thermal imaging non-destructive testing technology plays an indispensable role in the safe operation of equipment, product quality control and ensuring that equipment is in a safe and reliable state. With its unique advantages, infrared thermal imaging non-destructive testing technology has become a new type of digital testing technology that is currently focused on development. Compared with traditional detection technology, it has the advantages of wide application range, non-contact, fast speed, on-site use, high precision, ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art, and propose a method for reconstructing the shape of subsurface defects in thermal imaging detection, so as to facilitate the quantitative evaluation of subsurface defects and solve the problem of quantifying subsurface defects when surface excitation is used. analyse problem

Images