Failure mechanics in low-velocity impacts on thin composite plates

摘要: Eight-ply quasi-isotropic composite plates of Thornel 300 graphite in Narmco 5208 epoxy resin (T300/5208) were tested to establish the degree equivalence between low-velocity impact and static testing. Both deformation failure mechanics under representable by indentation tests. Under impacts such as tool drops, dominant mode was first, or static, mode. Higher modes are excited on contact, but they decay significantly time first-mode load reaches a maximum. The delamination patterns observed X-ray analysis. areas maximum coincided with highest peel stresses. extent similar for Fiber damage established tensile tests small fiber bundles obtained deplying test specimens. onset internal plies near lower surface plates. distribution amount fo