COMPARISON OF EXPERIMENTAL VELOCITY-MEASUREMENTS WITH THEORETICAL RESULTS IN A SOLID-SOLID COMPOSITE-MATERIAL

Two-phase composite media were constructed of aluminum powder inclusio ns embedded randomly in a clear resin matrix. The shapes of the inclus ions are elongate, with aspect ratios ranging from 0.1 to 1.0, averagi ng about 0.25. The effective velocities of ultrasonic elastic waves in the bulk media were measured for these composite materials, and the o bserved data were compared to the theoretical values calculated using five different numerical models. The observed velocities agree with th e theoretical values calculated using a dynamic model under the assump tion that the inclusions have an oblate spheroidal shape.