Mobilities and diffusivities for bcc Nb–W, Nb–Ta, Zr–Mo and Zr–Hf alloys

CALPHAD kinetic has evolved to maturity where the atomic mobilities can be combined with thermodynamic descriptions to retrieve kinetic quantities for nucleation and subsequent growth/coarsening. In order to assist computational design of refractory alloys that are indispensable for nuclear applications, the atomic mobilities and the related kinetic implications for bcc Nb–W, Nb–Ta, Zr–Mo and Zr–Hf alloys are studied in this work, based on the CALPHAD framework and the DICTRA software. The self-diffusion coefficients, impurity diffusion coefficients, tracer diffusion coefficients and interdiffusion coefficients for such binary systems are critically explored, the results of which are beneficial to facilitate alloy design and product development for the nuclear industry.

► The atomic mobilities in bcc Nb–W, Nb–Ta, Zr–Mo and Zr–Hf alloys are studied in this work. ► The obtained mobility parameters can reproduce relevant kinetic characteristics pretty well. ► This work complements the kinetic database of refractory alloys.