Stress rupture of unidirectional high performance thermoplastic composites in end-loaded bending at elevated temperatures. Part II: Analytical modeling

The equations of shape for a specimen under end-loaded bending are derived for a different coordinate axis using the theory of large displacements of buckled bars (The Elastica). The strain and stress distributions along the length of a unidirectional fiber reinforced composite undergoing stress rupture in end-loaded bending are established. Two life prediction models are constructed and compared to experimental results for an AS4/PPS composite. The models are respectively based on the nucleation and propagation of the microbuckles. The latter model compares well with the experimental stress rupture data for AS4/PPS composites in end-loaded bending at 120 degrees C.