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Nondestructive characterization of the elastic constants of fiber reinforced compositesComposite structural components may be subjected to a variety of defects resulting in a sharp reduction in their load carrying capacity or even catastrophic failure. Thus, it is extremely important to have the means to monitor the degradation suffered by critical components of a structure for safe operation during its service life. A nondestructive method based on ultrasonics has recently been developed for the quantitative evaluation of composite structural components during service. The experimental part of the technique uses a two-transducer, pitch-catch type arrangement to generate a variety of elastic waves within the specimen immersed in water. The recorded reflection data are then analyzed by means of a theoretical model to back out the relevant properties. In this paper the method is applied to determine the stiffness constants of unidirectional graphite/epoxy materials. The measurements are shown to be efficient and sufficiently accurate so that it can be used for early detection of material degradation in composite structural elements during service.
Document ID
19930049922
Document Type
Conference Paper
Authors
Mal, Ajit K. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Lih, Shyh-Shiuh (California Univ. Los Angeles, United States)
Bar-Cohen, Yoseph (JPL Pasadena, CA, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1993
Publication Information
Publication: In: AIAA(ASME)ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 34th and AIAA/ASME Adaptive Structures Forum, La Jolla, CA, Apr. 19-22, 1993, Technical Papers. Pt. 1 (A93-33876 1
Subject Category
STRUCTURAL MECHANICS
Report/Patent Number
AIAA PAPER 93-1349
Funding Number(s)
CONTRACT_GRANT: N00014-90-J-1857
Distribution Limits
Public
Copyright
Other

Related Records

IDRelationTitle19930049879Analytic PrimaryAIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 34th and AIAA/ASME Adaptive Structures Forum, La Jolla, CA, Apr. 19-22, 1993, Technical Papers. Pts. 1-6