Journal Published Online: 28 February 2014
Volume 3, Issue 3

Notch Fracture Toughness Evaluation for a Brittle Graphite Material



First, several disc-type test samples weakened by a central bean-shaped slit with two U-shaped ends, called U-notched Brazilian disc (UNBD) specimens, made of commercial graphite, were prepared. Four notch tip radii were considered in the tests. Then, a monotonic compressive load was diametrally applied to each sample along the slit, resulting in pure mode I loading. After sudden fracture, the fracture loads were recorded and converted into the corresponding values of the notch fracture toughness (NFT) KIρ,c. The main advantage of the UNBD specimen is that the NTF test can be easily conducted without using complicated fixtures. The well-established brittle fracture model, namely the strain energy density (SED) over a specified control volume, which embraces the notch edge, was employed to estimate the fracture loads theoretically. A good agreement was found between experimental and theoretical results. Under Mode I loading, the SED and the NFT are linked by a simple relationship providing a powerful tool for the fracture assessment of different specimens and structural components weakened by notches.

Author Information

Torabi, A.
Fracture Research Laboratory, Faculty of New Science and Technologies, Univ. of Tehran, Tehran, IR
Berto, F.
Department of Management and Engineering, Univ. of Padova, IT
Pages: 16
Price: $25.00
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Stock #: MPC20130041
ISSN: 2165-3992
DOI: 10.1520/MPC20130041