Mobility of screw dislocation in BCC tungsten at high temperature in presence of carbon

The interplay of screw dislocations with carbon atoms is investigated in tungsten at high temperature using situ straining experiments a transmission electron microscope (TEM) and through ab initio calculations. When the enough to activate diffusion, above 1373 K, segregates core modifies their mobility, even for concentration as low 1 appm. TEM observations reveal reappearance Peierls mechanism these temperatures, gliding viscously nucleation propagation kink-pairs. mobility saturated then calculations determine kink-pair formation, migration energies. These energies are used kinetic Monte-Carlo simulations an analytical model obtain velocity function temperature, applied stress dislocation length. obtained law parametrised on compares well experiments.