In-situ observation of dislocations and cavities interactions in tungsten at 973 K

To investigate the irradiation hardening mechanism involving dislocations and cavities interactions in tungsten, this study carried out the in-situ transmission electron microscopy observation under tensile test at 973 K. The obstacle barrier strength α and the fractions of cross- and double cross-slips generation at a cavity having a diameter of 2 nm in pure tungsten were determined as 0.50 ± 0.21 and approximately 37 % at 973 K, respectively. The fractions of cross- and double cross-slips generation of screw-type dislocations at a cavity were nearly identical at 723 K and 973 K. The types of generated double cross-slips were changed with increase in temperature.