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The propagation of leaky Lamb waves in a plate consisting of a general balanced symmetric composite material is considered. The problem has been examined both analytically as well as experimentally. An exact solution for the dispersion equation was obtained. Numerical results for complex-valued wavenumber were obtained for an isotropic material (aluminum) and a (0/90 3) s graphite/epoxy laminate. Excellent agreement for the isotropic case and a satisfactory agreement for the anisotropic case between the theory and experiment were observed.

A combined theoretical/experimental study of the heat transfer in thermoelectric Shape Memory Alloy (SMA) actuators is undertaken in this paper. A one-dimensional model of a thermoelectric unit cell with a SMA junction is developed rst and the transient temperatures in the SMA are evaluated for dierent applied electric current densities. As a rst step towards the design of an actuator, a thermoelectric module is assembled in the laboratory for cooling/heating the SMA. Transient temperature proles are recorded for the monotonic heating and cooling runs for two dierent materials copper and SMA (with or without the phase transformation). These recorded proles are then compared with the predictions from the model; the agreement is reasonable, particularly during the cooling process. Temperature proles are also recorded for cyclic cooling and heating of copper at a frequency of 0.5 Hz and a good comparison is obtained. Theoretical predictions for thermal cycling of SMA show that it is possible to achieve a frequency of 2 Hz on full phase transformation and 17 Hz on partial transformation of 25%.

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