Determination of the conditions of fracture of plutonium and its alloy with gallium under impact loading

We present the results of numerical analysis of the conditions of cleavage fracture of plutonium and its alloy containing 1.6 wt.% of gallium under impact loading. On the basis of the experimental data obtained earlier, we determine the critical tensile stresses corresponding to the initial stage of macroscopic cleavage fracture of specimens. In our calculations, we take into account the elastoplastic properties of materials and polymorphic transformations in the alloy at normal and elevated (315 deg C) temperatures.