SIMULATION OF HIGH-VELOCITY IMPACT OF GRAPHITE/EPOXY COMPOSITELAMINATES

摘要

The objective of the work presented in this paper is togenerate a thermodynamically consistent coupledmacro-homogeneous anisotropic thermo-elastic-plasticdamage model for fibre composites. The model is basedon the thermodynamics of irreversible processes and theassumption that damage within a continuum can berepresented as a damage tensor ωij [12], [13]. In orderto describe material behaviour under high-intensityloadings, a 3-D anisotropic elasto-plasticity constitutivemodel coupled with damage tensor, an equation of state,and a failure criterion for fibre composites have beendeveloped. The model includes the following keyaspects of the response of the materials to hypervelocityimpact, which occurs in the process of modeldevelopment: non-linear anisotropic strength, shockeffects and associated energy dependence, compaction,compressive and tensile failure, strain rate effects.The criterion for failure initialisation is the entropycriterion based on a critical value of a specific entropyfunction expressed through the dissipation function. Inorder to take into account different modes of compositefailure (fracture of fibres, fracture of matrix, de-lamination)several criteria were considered. Thesmoothed particle hydrodynamics (SPH) technique [4]has been proposed for the numerical simulation ofimpact damage and penetration of composite structures.The above physics were incorporated into the SPHsolver.