Yannick Pannier

Image-based modeling of moisture-induced swelling and stress in 2D textile composite materials using a global-local approach

The present paper focuses on the employment of a global-local approach for the simulation of moisture-induced swelling and stress in a 2D textile carbon fiber/epoxy matrix composite material. The approach is based on the development of a robust image-based finite element model built starting from X-ray microtomography scans of a repetitive unit cell of the textile material: simulations aim at investigating both the global (sample scale) level and the local micromechanical (interfaces between matrix and fibrous tows, matrix inside a tow) level behaviour. Three models at the different cited scales are first built (ply level model, tow level and fiber level model): then a non-concurrent (node-based) approach is used for coupling the models at different scales. The results of numerical simulation of moisture-induced swelling and stress are discussed, with emphasis on the identification of the most critical zones at which maximal stress values are calculated, at different scales.

Some Examples of “Multi-Physical” Fatigue of Organic Matrix Composites for Aircraft Applications

This paper presents, discusses and review some recent results concerning the interaction between mechanics and the environment during fatigue tests carried out under accelerated environmental conditioning of laminated and woven Organic Matrix Composites (OMC) for high temperature aircraft parts, the synergy between electrical and mechanical fields during electro-mechanical fatigue of composite laminates for fuselage applications the damage behavior of 3D woven OMC under thermal cycling.For all case studies, the capabilities of the PPRIME Institute to perform such tests reproducing “multi-physical” fatigue environment and characterizing the phenomenology associated to multi-physics coupling at several scales will be highlighted. The main issues related to the development of “multi-physics” models for proper interpretation of test results are also reviewed.