Analysis of thermal deformation on a honeycomb sandwich CFRP mirror

Thermal deformation analysis was performed on a carbon fiber reinforced plastic (CFRP) mirror with sandwich structure. To obtain unexpected asymmetry of the surface sheet, we investigated the deformation of a quasi-isotropic laminate under hot and humid conditions. Despite the symmetric lay-up, quasi-isotropic laminate deforms into twisted saddle shape with time, and this deformation could be simulated by assuming ply angle misalignment. Then, the elastic moduli of honeycomb cores were calculated theoretically. A honeycomb sandwich mirror model was constructed by adopting a sheet model and using honeycomb elements. The thermal deformation analysis was performed considering the ply angle misalignment. The test results clarified that the deformation of the surface sheet was a critical factor in the dimensional stability of the CFRP mirror.