A technique for obtaining shock-wave parameters using wave superposition in low-carbon steel

TLDR: In this article, a novel experimental set-up for obtaining shock-wave superposition is described, where two opposite sides of an explosive layer placed directly in contact with a steel block are simultaneously initiated at the two opposite side of the explosive layer.

Abstract: A novel experimental set-up for obtaining shock-wave superposition is described. Detonation is simultaneously initiated at the two opposite sides of an explosive layer placed directly in contact with a steel block. It was possible to take advantage of thea (bcc) → e (hcp) →α (bcc) transformation occurring in iron at approximately 13 GPa in a unique fashion. The pressure of the two converging pulses is approximately 13 GPa, resulting in little or no transformation. However, in the region of superposition of the two waves the pressure is much higher.Post explosionem observation of the microstructure allowed an easy identification of the region of superposition, because of the profuse transformation “debris”. Events conducted for three thicknesses of the explosive layers allowed conclusions to be drawn about the changes of rarefaction and attenuation rates. The interactions occurring between the waves due to simultaneous superposition and transformation are thought to be responsible for internal spalling.