Symmetric rod impact technique for dynamic yield determination

Abstract

An experimental technique has been designed and tested to determine the dynamic yield curve of a rod in compression at high strain rates (∼104−106/sec). The technique involves impacting a gas‐gun accelerated cylindrical rod onto an identical stationary rod at high velocities, and using a high‐speed framing camera to take silhouettes (at ∼106 frames/second) of the resulting deformation. A two‐dimensinal wave propagation code is then used to simulte the experiment, varying the yield parameters until the computational results approximate the experimental silhouettes. This technique is a refinement of the classical Taylor test, and eliminates the uncertainties of the boundary conditions as well as those caused by the Taylor formulae approximations. Results are presented for an experiment using 6061‐T6 aluminum.