Investigation of First Ply Failure in Graphite/Epoxy Laminates Subjected to Biaxial Static and Fatigue Loadings.

摘要

Thin graphite/epoxy (0/90)s and (+ or - 45)s tubes were loaded in various combinations of tension, torsion, and internal pressure, and physical evidence of first ply failure (FPF) was found using replication techniques. The FPF envelopes so identified were compared with ultimate strength envelopes, and with lamination theory predictions using a maximum strain criterion. Preliminary experiments were performed to examine the consequences of fatigue cycling inside of, and across the FPF envelope. (Author)