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.

Penetration resistance of laminated ceramic/polymer structures

“…El-Raheb and Tham [27] performed an experimental investigation of the wave propagation in a periodic stack of AlN ceramic tiles bonded by thin weak silicone rubber layers and obtained a phase velocity of 3.7 km/s in the laminated ceramic structure. It should be noted that both c p and c g diminish with an increase in frequency, with a maximum at zero frequency (given by Eq.…”

“…A two-dimensional analysis of the same problem demonstrated increased attenuation of the peak normal stresses along the stack because of radial spreading from the flexural waves. El-Raheb and Tham [27] performed nondestructive experiments on periodic stacks of aluminum nitride (AlN) tiles bonded by thin weak silicone glue. The pressure at the interface of the ceramic and bond layers was measured by carbon gauges along the centerline of the stack.…”

Wave propagation in functionally graded and layered materials

“…[6] to understand the dispersion in laminated composite plates. Plate impact experiments are made on aluminum nitride ceramic tiles bonded with thin silicon rubber at velocities ranging from 14 to 58 m/s in [7]. They concluded that the pulse is spread radially by the flexural waves.…”