Abstract
A modified technique to measure acoustic nonlinearity in fatigued components is proposed in this paper. As opposed to the conventional technique to measure acoustic nonlinearity, the proposed technique eliminates the couplant effects between the transducers and the specimen. The proposed technique is compared with the conventional technique by performing nonlinearity measurements on a fatigued aluminum alloy specimen and calculating the coefficient of variation (COV) of the nonlinearity parameter. Preliminary results show that the COV of the nonlinearity parameter obtained using the modified technique is approximately half of that obtained using conventional technique. It is therefore felt that the proposed technique will help to reduce the variability in the nonlinearity measurements in fatigued components.