Defect Identification in Thermographic Nondestructive Testing under Cyclic Heating Using SVD Thermo-Component Analysis

Abstract

This study applied SVD (singular value decomposition) thermo-component analysis to defect detection using active infrared thermography. SVD decomposes time-series thermal image data into a temperature time-series waveform (PC) and a relative-value distribution image with a PC waveform (EOF image). It is possible to clarify the physical meaning of the EOF image based on the analysis of the PC waveform. The optimal EOF image that coincides with the characteristic thermal variation image due to the effect of defects can be selected.

Keywords

• nondestructive inspection
• active infrared thermography
• multivariate analysis
• singular value decomposition