The effect of initial porosity of a sample under electric explosion loading

Abstract

Abstract. Tubular Al 2 O 3 ceramic samples were destroyed under shock wave loading using electrical explosion wire (EEW) in a liquid. The fragments were classified into two types: quasi-two-dimensional (2D) samples, the characteristic size of which, d*, was greater than (or equal to) the tube wall thickness; and three-dimensional (3D) samples of the size d* < d. The study of the influence of the initial sample porosity indicates a direct effect on the formation of 3D fragments, and the distribution of the porosity is described by the power law function with an exponent differing from that of the 3D fragments size distribution. According to the scenario, the initial defects (pores) provide conditions for multi-site fracture of ceramics under high-rate loading. The instability of fast crack propagation leads to micro-branching, which creates conditions for the formation of the 3D objects. The 3D fragments size distribution is described by the power law, which corresponds to the micro-branch distribution.