Accelerated hygrothermal cyclical tests for carbon/epoxy laminates

The paper is related to a supersonic transportation application where polymer matrix composites utilized in primary structures are subjected to particular hygrothermal flight-cycles. In fact, the particular point in this study is the drying effect of supersonic flight at high temperature, around 130°C, on the durability of the material. This phenomenon constitutes an entirely new situation for these materials in contrast with a classical subsonic flight at low temperature. The supersonic aircraft is supposed to be subjected to a succession of supersonic flight-cycles followed by a periodic maintenance operation. The objective of the study is first to characterize the in-service material state during the supersonic flight cycles and after the maintenance operations. Then, the challenge is to define the material geometry and environmental conditions to meet the in-service material state in short time. Thus, different accelerated cycles adapted to the new situation of supersonic flights, i.e. focusing on the cyclical drying of the material, are proposed