Mode I, Mode II, and mixed mode interlaminar fracture of woven fabric carbon/epoxy

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:675576

Alif, N; Carlsson, L A ^[1]; Gillespie, Jr, J W ^[2]

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1. Florida Atlantic Univ., Boca Raton, FL (United States). Dept. of Mechanical Engineering
2. Univ. of Delaware, Newark, DE (United States). Center of Composite Materials

Interlaminar fracture behavior of a five-harness satin orthogonal woven fabric carbon/epoxy composite laminate loaded in Mode I, Mode II, and mixed mode has been investigated. Fracture testing employed the DCB, ENF, and MMB specimens. Special emphasis was put on microscopic details of crack growth and their relation to fracture resistance. For all fracture mode combinations it was found that crack growth occurred in a nonplanar region of topology determined by the weave pattern and relative positioning of the plies adjacent to the crack plane. The woven fabric structure constrains fiber bridging, but partial debonding of transversely oriented fiber bundles led to occasional crack branching, stick-slip behavior leading to variations in the Mode I fracture resistance. Slow stable crack growth occurred in the ENF and MMB specimens prior to unstable fracture and resulted in nonlinear load-displacement response.. A linear relation between the critical values of G{sub I} and G{sub II} was observed.

• OSTI ID: 675576
• Report Number(s): CONF-9605345--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON FIBERS
COMPOSITE MATERIALS
CRACK PROPAGATION
EPOXIDES
FRACTURE MECHANICS
FRACTURE PROPERTIES
MECHANICAL TESTS