Abstract
In this paper the effect of an applied stress on the principal polarisation directions of ultrasonic shear waves in textured materials exhibiting orthorhombic symmetry is investigated. The parameters entering into an expression for the rotation of the polarisation direction with applied stress, derived by Okada (1980) by analogy with the approach used in optics, are expressed in terms of the second- and third-order elastic constants of the material. These constants are obtained for mild steel from measurements of the stress dependence of the ultrasonic velocities. The predicted variation in the polarisation direction with stress is found to agree well with measurements for a mild steel plate subjected to a uniaxial stress at various angles to the principal texture axis.