Improving mechanical properties and achieving structural stability of large-size molybdenum single crystal during hot deformation by adding Nb element.

The occurrence of recrystallization will cause catastrophic damage to the structure of the metallic single crystal, which can be avoided by alloying reasonably. In this work, a new strategy is proposed to improve mechanical properties and achieve the structural stability of Mo single crystal during hot deformation. Thermal simulation tests show that the mechanical property of Mo single crystal is significantly improved by adding the Nb element. The Nb element is beneficial to inhibit the dynamic recrystallization of Mo single crystals through blocking the development of high-angle grain boundaries and dislocation cells, leading to Mo-Nb alloy single crystals still retaining monocrystal structure. [Display omitted] • Mechanical properties of Mo single crystal are significantly improved by adding Nb element. • The dynamic recrystallization occurred in pure Mo single crystal, while Mo-Nb alloy single crystals still retain monocrystal structure. • The development of HAGBs and dislocation cells are blocked by Nb atoms. [ABSTRACT FROM AUTHOR]