A parametric study on defect sizing in plates using lamb wave reflection coefficients

Abstract

In this paper, a parametric study is reported to examine whether a combination of reflection coefficients corresponding to ultrasonic mode converted S0 and A0 Lamb waves lead to a better estimation of the depth of defects in metal plates. The A0 reflection coefficient, when plotted as a function of the ratio between the crack depth and the plate thickness shows a dip, which results in an ambiguity related to the dimensioning of the crack depth. Our study shows that on the other hand the S0 reflection coefficient curve follows a more distinct trend with increasing crack depth and plate thickness ratio. Therefore, this information along with the A0 reflection coefficient information facilitates more accurate defect sizing.