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In this study, the strain rate concentration is considered for high speed tensile test,
which is now being recognized as a standard testing method. To evaluate the impact strength
of engineering materials, Izod and Charpy tests are unsuitable since they cannot control the
impact speeds and therefore the testing results do not coincide with the real failure of real
products. For smooth specimens, the strain rate can be determined from the tensile speed u/t
and specimen length l as ε̇smooth=u/tl.
For notched specimens, however, the strain rate at
the notch root ε̇notch should be analyzed accurately.
In this study, therefore, the strain rate
concentration factor defined as Kt ε̇ = ε̇notch/ε̇smooth
is studied with varying the notch
geometry and specimen length for round and flat test specimens. In particular, the relationship
between the strain rate concentration factor and the stress concentration factor is investigated
by varying the notch geometry and specimen length.
Keywords: notch fracture, high speed tensile test, strain rate concentration factor, stress concentration factor |
full paper (pdf, 944 Kb)