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More and more aircraft components are made of fiber reinforced composite material because of high stiffness, strength and low weight. These composites are made of glass or carbon fibers embedded into a polymer matrix. In some case, for equivalent energy absorption, composite components can be 50% lighter than steel components. The resistance of aircraft composite components to impact of various debris or birds must be assessed. Extensive literature exists describing the energy absorption mechanism of composite laminate tubes crushed between two rigid plates. Triggers are usually used to initiate material peeling inside and outside of the tube. The energy is absorbed by more complex mechanisms than for metallic tubes, such as delamination, fibers debonding, pulverization of material and friction. A constitutive model using damage mechanics is described in this paper. The model has been validated on composite tube crushing. This paper also describes the numerical results obtained with RADIOSS for the crash of composite sine wave beam and of sub cargo floor structure. Bird strike simulation results are also shown in the case of impact on a commuter leading edge structure. Comparison with tests results is shown. RADIOSS is an explicit finite element code developed by MECALOG, used for non linear simulations and validated industrially for crash analysis of metallic structures in automotive and aeronautic applications.

Laser Beam Melting is actually capable of producing parts with reliable mechanical properties. However, efficient production still remains a challenge and high quality numerical simulation is required in order to understand the physical mechanisms involved. Consequently, a macroscopic numerical model at part scale is actually under development for understanding the relationship between different process and material parameters with the mechanical state of final parts such as distortion and residual stress. Classical finite element method is used to solve the coupled thermo-mechanical problem on the whole domain defined by the workpiece, the baseplate and the support structures. At this scale, powder packing is neglected as well as the hydrodynamics behavior within the melt pool. Homogeneous equivalent heat source is used and imposed until several layers below the current deposited layer. Elastoplastic constitutive material law with temperature dependent parameters has been developed.

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