Wave Propagation in a Linear Thermo-Magneto-Elastic Material

Abstract

Acceleration wave propagation in an isotropic homogeneous linear thermo-magneto-elastic material is investigated. A thermo-electrical interaction is taken into account in the heat equation to restrain the infinite velocity of thermal disturbances. There exist four types of coupled waves : an electro-acoustical wave, two thermo-acoustical waves and an electro-magnetic wave. The amplitudes of all the waves, in general, decay exponentially in time, but the damping constants depend, in different ways, on the propagation directions and the thermo-magneto-elastic properties of the material. Especially, according as the angles between the initial magnetic field and propagation directions vary from 0 to π/2, the damping constant of the electro-acoustical wave decreases to 0, and those of the thermo-acoustical waves increase. On the other hand, the damping constant of the electro-magnetic wave depends also on the angle between the initial magnetic field and the direction of its amplitude, and it gives rise to the elliptical polarization.