Dynamic Biaxial Compression of CFRP Laminates Using Electromagnetic Loading

The dynamic biaxial compression test for carbon-fiber-reinforced polymer (CFRP) laminates was carried out via synchronous electromagnetic loading in this study. During the experiments, four stress pulses transmitted along four incident bars, loading the square specimen simultaneously from four directions to keep the center of the specimen still. The dynamic mechanical behavior of CFRP was obtained employing the one-dimensional wave propagation theory, and the deformation and failure processes of the specimens were recorded by a high-speed camera. The effects of various biaxial stresses on the compressive strength were investigated in three biaxial and one uniaxial loading cases. For the CFRP laminates, the dynamic transverse compressive stress showed little effect on the longitudinal ultimate compressive strength. Numerical simulations were performed to understand the dynamic stress wave propagation. It showed that the employed loading device could guarantee good biaxial loading conditions until the ultimate failure of the specimens. This approach allows for the dynamic biaxial compression testing of various materials, which is of great significance in evaluating the dynamic impact performance of aeronautical composites.