Principles and Application of Ultrasonic Spectroscopy in NDE of Adhesive Bonds

Ultrasonic Measurement of Thickness, Density and Elastic Moduli of a Layer Embedded into a Solid

“…The error for dimensional parameters (lower part of the Table 1 is several times larger than that for nondimensional parameters due to their recalculation by equations (5)- (8). The source of the error increase is in (h~ -h~1)11 2 , where ht and hot are close to each other. In general, the precision of dimensional parameter determination does not exceed a few percent with the largest error for density (3.7%) and attenuations (5.4% and 6.5%) at 5% noise Ievel which is unlikely for actual experimental measurement.…”

“…Flynn (1] and Changetal (2] determined ultrasonic velocity and attenuation from the ultrasonic refl.ected signal and correlated them with the joint cohesive strength. The infl.uence of frequency dependent attenuation on amplitude and phase spectra of the signal refl.ected from the joint bondline was studied in (3].…”

An Ultrasonic Method for Simultaneous Determination of Elastic Moduli, Density, Attenuation and Thickness of a Polymer Coating on a Foil

“…It has been shown in [15] At oblique incidence both longitudinal and shear waves are excited inside the layer. Reflection and transmission coefficients depend on six layer parameters: elastic moduli, thickness, density, and longitudinal and shear wave attenuations: (2) A full set of nondimensional parameters defining oblique incidence reflection and transmission includes ZN, hl and al and three more nondimensional parameters: two nondimensional thicknesses hoI. and hot at oblique incidence and shear wave attenuation at…”

Characterization of adhesively bonded joints using acousto-ultrasonics

“…The technique has been used to detect the quality variations of the aluminium alloy bonded joints due to fabrication processes [42,43] and due to hydrothermal degradation [44]. Chang et al [45] reported a linear relationship between the bond strength in aluminium single lap-shear specimens and ultrasonic parameters obtained from the ultrasonic spectroscopy technique.…”