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This paper is concerned with the thermoelastic response of a functionally graded thin plate with an analytical approach. The governing equations are derived in the context of the Lord and Shulman theory (L-S theory), where the material properties of the thin plate are assumed to be graded along the lengthwise direction according to a power law distribution.An asymptotic approach based on the layer method and the Laplace transform technique is presented to deal with these nonlinear governing equations, and then the closed-form solutions of displacement, temperature and stresses, induced by a sudden temperature rise at the boundary, are derived. The propagation of each wave, as well as the distributions of each physical field, are plotted and discussed. The comparison is also conducted to evaluate the effect of characteristic parameter, including the thermal relaxation time and the power law index, on thermoelastic response.

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The ultra-high plastic deformation behavior by laser shock processing on the LY12 aluminum alloy had been investigated. The morphology of the materials had been analyzed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). It was found that the grain refinement layer was formed in the thickness of about 100μm .The dislocation density of LY12 aluminum alloy should be large increased after laser shocking because the accumulation of dislocation was appeared on the grain boundary. With the laser energy density increased there formed subgrain structure and eventually generate ultra-fine grain. Hardness test results also show that the surface hardness obtains a big growth about 60% after laser shock processing. The results showed that the formation of ultra-high plastic strain can improve the surface hardness of LY12 aluminum alloy, and thus effectively improve the comprehensive mechanical properties.