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Accession Number ADA571181
Title Impact Damage Detection of Toughened CFRP Laminates with Time Domain Reflectometry.
Publication Date Jan 2013
Media Count 13p
Personal Author A. Todoroki
Abstract Laminated Carbon Fiber Reinforced Polymer (CFRP) composites are very effective in weight saving in aeronautical structural components. It is, however, difficult to detect damage such as delamination, matrix cracks, and local fiber breakages caused by low velocity impact loading. In the previous study in 2009, Time Domain Reflectometry (TDR) method was applied to a unidirectional laminated CFRP structure for the first time. In 2010, the research applied the TDR method for the CFRP laminates. In the present study, therefore, actual impact damage is employed instead for the TDR. Electrical contact between fiber fragments exists in these micro-buckling regions although the electrical resistance becomes very high at the micro-buckling point. We have to investigate the applicability of the TDR method for the impact damage. A low speed impact test is performed to a cross-ply CFRP plate, and impact damage is made at the surface of the CFRP plate. TDR is applied to the cross- ply CFRP plate. The result shows that the reflected signal can be observed after the impact test. This result indicates that the TDR method is useful for detection of the low speed impact damages.
Keywords Buckling
Carbon fiber composites
Carbon fibers
Cfrp(Carbon fiber reinforced polymers)
Composite materials
Damage
Detection
Equations
Finite difference methods
Gfrp(Glass fiber reinforced polymers)
Impact damage
Impact tests
Laminated plastics
Low velocity
Microbuckling
Nondestructive testing
Reflectometers
Reinforced plastics
Tdr(Time domain reflectometry)
Time domain

 
Source Agency Non Paid ADAS
NTIS Subject Category 71F - Composite Materials
Corporate Author Tokyo Inst. of Tech. (Japan). Dept. of Materials Science and Engineering.
Document Type Technical report
Title Note Final rept. 11 Oct 2011-11 Dec 2012.
NTIS Issue Number 1315
Contract Number FA2386-11-1-4036

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