Transient waves in a periodic stack: Experiments and comparison with analysis

Abstract

Transient waves were initiated by allowing a thick PMMA disk to strike a periodic stack of ceramic layers bonded by thin weak silicone rubber layers. Pressure at interfaces of ceramic and bond layers was measured by carbon gauges along the centerline of the stack. Comparison of experimental histories with those from a 1-D analysis [J. Acoust. Soc. Am. 94, 172–184 (1993)] and a 2-D axisymmetric analysis [J. Acoust. Soc. Am. 99, 3513–3527 (1996)] reveals that waves propagate two-dimensionally and that flexure of the ceramic layers controls attenuation and shape of compressive wave of first arrival. Viscoelasticity of the bond material sharply reduces tensile stresses.