Multi-objective optimization of hybrid laminates subjected to transverse impact

The present paper deals with optimization of hybrid fiber reinforced plastic laminated plates subjected to impact loading. Finite element method (FEM) and genetic algorithm (GA) have been used to obtain optimum laminate in terms of minimizing the cost, weight or both cost and weight of graphite/epoxy (T300/5208)-aramid/epoxy (Kevlar 49) hybrid laminates while maximizing the strength. Impact induced delamination and matrix cracking have been used as failure criteria for the optimization of laminate. Fiber orientation, material and thickness in each lamina as well as number of lamina in the laminate have been used as design variables. Multi-objective approach has been used to achieve the optimum design of a laminate for combined normalized weighted cost and weight minimization. The results obtained from the integrated module show that GA with FEM can lead to a near optimal solution for both single as well multiple objective functions. (C) 2005 Elsevier Ltd. All rights reserved.