Plasticity of Barium Fluoride Single Crystals

Abstract

Barium fluoride single crystals exhibit considerable plasticity at 200°C. Between room temperature and 200°C, they slip in a (100) plane and in a [110] direction. By using etch pit techniques, it was observed that at 200°C fresh dislocations introduced by sprinkling with hard particles start to move at a stress level considerably lower than that indicated by compressive yielding at the same temperature. Fracture in barium fluoride, induced by microhardness indentation, took place on {111} and on {100} planes; the {111} cleavage fracture was more common than {100} fracture.