Dynamic Tensile Characteristics of Nuclear-Grade Graphite IG-11

Abstract:

The effect of strain rate up to nearly = 10²/s on the tensile stress-strain properties of isotropic fine-grained nuclear-grade graphite IG-11 was investigated. Cylindrical tensile specimens machined out of graphite bars were used in both static and dynamic tests. The dynamic tensile stress-strain curves up to fracture were determined using the split Hopkinson bar (SHB). The low and intermediate strain-rate tensile stress-strain relations up to fracture were measured on an Instron 5500R testing machine. It was demonstrated that the ultimate tensile strength increases slightly, while the fracture strain and absorbed energy up to fracture decrease dramatically with increasing strain rate. Macro and microscopic examinations revealed a slight difference in the fracture surfaces between the static and dynamic tension specimens.

• Periodical: Applied Mechanics and Materials (Volume 566)
• Pages: 61-66
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.566.61
• Online since: June 2014
• Authors: Takashi Yokoyama*, Kenji Nakai
• Keywords: Earthquake Loading, Fracture Mode, Graphite Reactor, Hopkinson Bar, Nuclear-Grade Graphite, SEM Examination, Strain Rate, Tensile Behavior

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