High-force dynamic mechanical analysis of composite sandwich panels for aerospace structures

High-force dynamic mechanical analysis (DMA) has enabled the non-destructive evaluation of thermo-mechanical properties for highly stiff structures over a range of loading frequencies, allowing for additional insight not provided by commonly used static and impact test procedures. In this study, carbon fiber composite sandwich panels with both aluminum and aramid honeycomb cores are characterized based on application conditions in the airframe structure of a high-performance two passenger aircraft. The relative stiffness and damping ability across critical flight frequencies (1 – 100 Hz) for different panel cores are compared. It is found that the damping of the composite sandwich panels is dependent on the applied static load as well as the core material used. Temperature sweeps are also conducted and found to be capable of detecting differences in the glass transition temperature of the composite face sheet matrix material based on post-curing procedures of the manufactured panels.