Influence of the fastening between thread–test samples in the stress–strain curves in tensile dynamic tests

Abstract

A Hopkinson tensile bar has been numerically simulated by means of the commercial software ABAQUS, with different gaps between the sample and the incident and the transmitted bars. This simulated a poor adjustment in the preparation of the tests and observed the effect the measurements of the stress of the incident, reflected and transmitted bars might have in the results of the stress-time and strain-time curves, as well as in the stress-strain curve of an aluminum sample. It is verified that the gap may significantly affect the elastic limit to be obtained from the dynamic tests and the expected results of the ultimate stress and deformation, and also affect the sample stress-strain curve to a large extent. We also concluded in the importance that is necessary in the testing equipment for a dynamic characterization of materials, in this case, the equipment for dynamic tensile testing.

Numerical Design of a Thread-Optimized Gripping System for Lap Joint Testing in a Split Hopkinson Apparatus

“…González-Lezcano et al [ 25 ] performed a numerical study where an initial dynamic-explicit numerical model of a tensile SHB was defined and compared with experimental measurements. Afterwards, in this study, a numerical analysis of the thread clearance was performed to determine if such a parameter would distort the wave.…”