An Improved Load Introduction Technique for Dynamic Material Characterisation at Intermediate Strain Rate

Abstract

Dynamic properties at intermediate strain rate are inherently difficult due to the dynamic interactions between the test specimen and the test machine. These effects obscure the interpretation of test results and therefore can make the derivation of the material properties difficult and unprecise. Soft materials can be used within load introduction devices to mitigate the inertia effect that typically occurs in dynamic tests. In this paper, dynamic tensile tests were performed within the strain rate range of 0.1 s−1 to 400 s−1 on high strength steels. With the aim of evaluating the performance of damping materials in the slack adaptor, copper and acrylic tapes were used. Experimental results show that both damping materials may be used to effectively reduce the oscillations in the measured force signal. The outcome of this project will provide the test procedure for dynamic testing at intermediate strain rates, which can produce reliable test results for materials with low failure to strain.