Isothermal annealing of thin rolled tungsten plates in the temperature range from 1300 °C to 1400 °C

The annealing behavior of thin tungsten plates of four different thicknesses achieved by warm- and (in two cases) cold-rolling is investigated. Isothermal experiments at five different temperatures between 1300 °C to 1400 °C were performed. Hardness testing of annealed specimens allowed tracking the degradation of the mechanical properties and, indirectly, the microstructural evolution. Supplementary microscopical investigations of the microstructure in the as-received state as well as after annealing were performed to characterize the initial condition and to support the identification of the involved restoration processes. All four tungsten plates undergo microstructural restoration by recovery and recrystallization. The observed differences in their behavior were rationalized in terms of the identified differences in the microstructure in the as-received state, rather than their different initial thickness.