Subsonic and intersonic dynamic crack growth in unidirectional composites

Date

1999-12-01

Author

Çöker, Demirkan
Huang, Yonggang Y.

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Some recent experimental observations of highly dynamic crack growth events in thick unidirectional graphite fiber-reinforced epoxy matrix composite plates are presented. The composite plates were symmetrically (mode-I) and asymmetrically (mode-II) loaded in a one-point bend configuration with an edge pre-notch machined in the fiber direction. The lateral shearing interferometric technique of coherent gradient sensing (CGS) was used in conjunction with high-speed photography. Symmetric, mode-I cracks initiated at 1300 m/s and subsequently accelerated up to the Rayleigh wave speed but never exceeded it. For asymmetric, Mode-II types of loading, the results reveal highly unstable and intersonic, shear-dominated crack growth along the fibers. The intersonic cracks propagated with unprecedented speeds reaching 7400 m/s, more than three times the shear wave speed of the composite, and featured a shock wave structure typical of disturbances travelling with speeds higher than one of the characteristic wave speeds in the solid.

URI

https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0033298568&origin=inward
https://hdl.handle.net/11511/86029

Journal

American Society of Mechanical Engineers, Applied Mechanics Division, AMD

Collections

Department of Aerospace Engineering, Article

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Citation Formats

D. Çöker and Y. Y. Huang, “Subsonic and intersonic dynamic crack growth in unidirectional composites,” American Society of Mechanical Engineers, Applied Mechanics Division, AMD, pp. 75–86, 1999, Accessed: 00, 2021. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0033298568&origin=inward.