Informative Parameters and Noise in Transient Thermal NDT

Detail description of physical and derived informative parameters used in transient thermal NDT is presented. Features of temperature-domain and time-domain parameters are discussed. Expressions for signal-to-noise ratio are specified and efficiency of spatial filters applied to IR thermograms with defects is discussed. Spatial frequency spectrums are obtained in non-defect and defect areas using fast Fourier transform.