Dislocation Mobility In Gum Metal Beta-Titanium Alloy Studied Via In Situ Transmission Electron Microscopy

In situ tensile tests in a transmission electron microscope were carried out on a "Gum Metal" beta-titanium alloy. Conventional dislocation slip was observed to be the only mechanism occurring during the plastic deformation. The low mobility of screw dislocations was shown to be due to their core structure configuration. Nanometer-sized obstacles were also present but have a weaker effect on the dislocation mobility. The density of these obstacles and the variation in energy due to the core structure of screw dislocations were measured and compared to theoretical data in the literature.