Eur. Phys. J. Special Topics 227, 45–54 (2018)
https://doi.org/10.1140/epjst/e2018-00112-y

Regular Article

Shockless spalling characterization of ceramics in a 1D-stress state

CEA, DAM, CEA-Gramat, 46500 Gramat, France

^a e-mail: benjamin.erzar@cea.fr

Received: 6 November 2017
Received in final form: 12 January 2018
Published online: 10 September 2018

Abstract

Ceramics are particularly interesting as protective materials due to their high compressive strength. However the maximum tensile stress withstood by these materials is usually lower by one order of magnitude. To study the dynamic strength in tension, spalling tests are commonly performed. In this work, a new spalling configuration is presented to characterize brittle materials such as ceramics at ultra-high strain-rates of about 10³–10⁴ s⁻¹ in a one-dimensional stress state. To do so, a specific test is designed in which the ceramic specimen is a bar with a 3 mm radius. This geometry is chosen to ensure a one-dimensional stress state in the cylindrical specimen avoiding wave dispersion during the propagation of the loading pulse. Finally, the first experimental validation tests conducted at the CEA-Gramat with the pulsed power generator called GEPI are reported.