Abstract Ultrasonic treatment of commercially pure ultrafine-grained Ti processed by high pressure torsion is performed. Measurements show no significant relaxation of the structure and no changes in both microhardness and microdeformation even at the maximum possible ultrasound amplitudes. Validation of the experimental observations is made with the help of molecular dynamics simulation of bicrystals containing non-equilibrium grain boundaries. It turns out that the relaxation of grain boundaries in Ti requires much higher strain amplitudes than those that can be achieved experimentally. The results are compared with those obtained previously for pure ultrafine-grained Ni, where a significant relaxation of the microstructure has been observed.

中文翻译：

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超细晶钛的超声波处理

摘要 对经高压扭转加工的商业纯超细晶钛进行超声处理。测量结果表明，即使在最大可能的超声振幅下，结构也没有显着松弛，显微硬度和微变形也没有变化。在包含非平衡晶界的双晶的分子动力学模拟的帮助下，对实验观察进行了验证。事实证明，Ti 中晶界的松弛需要比通过实验获得的应变幅度高得多的应变幅度。将结果与之前获得的纯超细晶粒 Ni 的结果进行比较，观察到显着的微观结构松弛。