Effect of Deformation on the Diffusion Properties of β-Zr at High Temperatures

The method of classical molecular dynamics with application of moment tensor potential of interatomic interaction were used to study diffusion properties of pure bcc β-Zr in the temperature range 1800–2100 K. The used potential was pre-trained on the data of ab initio calculations and verified by comparing the calculation results with the available experimental and theoretical data. The constructed potential reproduces the temperature phase transition from hcp α-Zr to bcc β-Zr, the experimental values of the thermal expansion coefficient and the diffusion coefficient, as well as the ab initio calculated equations of state of both phases at low temperatures. The dependence of the self-diffusion coefficient in zirconium on the strain in the range from –3 to 3% is obtained. It is shown that melting of the distorted structure can occur at a temperature below the melting temperature of the undeformed crystal.