Crack arrest and residual strength of composite panels with softening strips

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Journal of Aerospace Engineering; (USA)

DOI:https://doi.org/10.1061/(ASCE)0893-1321(1991)4:1(78)· OSTI ID:6020838

Chu, C S ^[1]

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1. Lockheed Aeronautical Systems Co., Marietta, GA (USA)

The residual strength and crack-arresting capabilities of laminates with softening strips of either E-glass, Kevlar, or S-glass are investigated. Sixteen-ply panels (with strips replacing the 0 deg-ply fibers) are tested under different conditions including fatigue cycling (before and after an initial damage is introduced), and exposure to environmental moisture. It is found that S-glass functions better than Kevlar and E-glass in the crack-arrest and residual strength test (even though it experiences greater delamination than the other two materials); that the residual strength is not influenced by the size of the initial damage; and that moisture significantly affects the crack-arrest capability. It is concluded that these materials cannot be used as a crack-arrest mechanism for the fail-safe design of composite aircraft structures. 8 refs.

• OSTI ID: 6020838
• Journal Information: Journal of Aerospace Engineering; (USA), Journal Name: Journal of Aerospace Engineering; (USA) Vol. 4; ISSN 0893-1321; ISSN JAEEE
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
AIRCRAFT
ARAMIDS
CARBON
COMPOSITE MATERIALS
CRACK PROPAGATION
ELEMENTAL MINERALS
ELEMENTS
EPOXIDES
FAILURES
FATIGUE
FRACTURE PROPERTIES
GLASS
GRAPHITE
LAYERS
MATERIALS
MECHANICAL PROPERTIES
MINERALS
MOISTURE
NONMETALS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORIENTATION
PANELS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
SYNTHETIC MATERIALS