A new analytical model was established to describe the complex behavior of ceramic/metal armor under impact of deformable projectile by assuming some hypotheses. Three aspects were taken into account: the mushrooming deformation of the projectile, the fragment of ceramic tile and the formation and change of ceramic conoid and the deformation of the metal backup plate. Solving the set of equations, all the variables were obtained for the different impact velocities: the extent and particle velocity in rigid zone; the extent, cross-section area and particle velocity in plastic zone; the velocity and depth of penetration of projectile to the target; the reduction in volume and compressive strength of the fractured ceramic conoid; the displacement and movement velocity of the effective zone of backup plate. Agreement observed among analytical result, numerical simulation and experimental result confirms the validity of the model, suggesting the model developed can be a useful tool for ceramic/metal armor design.

Dynamic-Relaxation Method( DRM) is applied to studying the influence of compression-bending coupling on nonlinear behavior of cylindrically slightly curved panels of unsymmetric laminated composite materials subjected to uniform uniaxial compression during loading and unloading. Numerical results are given for cross-ply plates and panels under $4S4 and $4S2 boundary conditions. The results show that the effects of absolute value and the sign of the coupling coefficient on the stability behavior of the pantes are significant.