- The presented experimental technique uses a radial sample pre‐stressing in order to reveal whether the behavior of ceramics is brittle or ductile under uniaxial shock‐wave compression. The controlled radial pre‐stressing of ceramic samples was produced by a shrink‐fit steel sleeve. The HEL increment caused by the pre‐stressing was expected to be of about 2.5 times higher for materials whose brittle failure in compression is governed by Griffith’s criterion than for those that obeyed the Von Mises criterion of ductile yielding. The experiments indicate certainly ductile behavior of hot‐pressed alumina samples whereas the samples of hot‐pressed high‐density (2.5 g/cm3) boron carbide exhibit compressive failure. The lateral pre‐stressing of boron carbide samples of lower density (2.37 g/cm3) results in a slight HEL decrease that is treated in terms of a compaction process.