

Ultrasonic Scattering in Polycrystalline Materials under Applied Loads
Abstract
Previous research on acoustoelasticity has focused primarily on homogeneous materials (isotropic or crystalline) for which ultrasonic wave speed changes as a function of applied stress have been determined. However, the majority of structural materials of interest are heterogeneous such that ultrasonic scattering occurs when the wave length is on the order of the length scale of the microstructure. In this article, scattering from polycrystalline materials under applied stress is examined both theoretically and experimentally. The scattering is governed by the second-order orientation statistics of the grain moduli which depends quadratically on the applied stress. Applications for stress measurements are discussed.
Keywords
ultrasound; wave scattering; nonlinear response;Text