The structure and occurrence of the metastable monoclinic phase, α′ b, in uranium-molybdenum alloys

Abstract

The atomic positions of the metastable, monoclinic, α′ b phase occurring in uranium-molybdenum alloys have been determined for a specimen containing 10 at % Mo. The effects of alloy content and temperature on these positions have been studied. It has been shown that for specimens containing 9.2, 10 and 10.8 at % Mo this structure is a result of a transformation, probably by a shear process, from a tetragonal phase which is based on the body-centred cubic structure of gamma uranium. The relationship between the atomic positions in the monoclinic cell and in the parent gamma phase and equilibrium alpha phase of uranium is discussed.