Microstructure and room temperature mechanical properties of α-titanium alloy Ti-5Al-0.5 V subjected to equal channel angular pressing (ECAP) and subsequent ultrasonic treatment (UST) have been studied. The ECAP was carried out at 600 °C by route B_c and the UST at the frequency of 20 kHz and amplitude of compression-tension stresses of 100 MPa for processing time of 60 s. The dislocation densities after ECAP and subsequent UST were estimated by x-ray diffraction and positron lifetime spectroscopy. By the latter, vacancy concentration also was determined. It has been shown that UST results in a very little increase in the dislocation density and vacancy concentration and has no considerable effect on the mechanical properties of the ECAP-ed titanium alloys. Basing on the data obtained and earlier published results of computer simulations of the behavior of nonequilibrium grain boundaries in Ni and Ti under the action of ultrasound it is concluded that the structural transformations in Ti under UST occur at much higher stresses than in Ni, in which UST results in significant modifications of the structure and properties.

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中文翻译：

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Ti-5Al-0.5V合金等通道角挤压超声处理

研究了α-钛合金Ti-5Al-0.5 V在等通道角挤压（ECAP）和后续超声处理（UST）下的显微组织和室温力学性能。ECAP 通过路线 B _c在 600 °C 下进行和 UST 在 20 kHz 的频率和 100 MPa 的压拉应力振幅下，处理时间为 60 s。ECAP 和随后的 UST 后的位错密度通过 X 射线衍射和正电子寿命光谱估计。通过后者，空位浓度也被确定。已经表明，UST 导致位错密度和空位浓度的增加非常小，并且对 ECAP 处理的钛合金的机械性能没有显着影响。根据获得的数据和早先发表的对超声作用下 Ni 和 Ti 中非平衡晶界行为的计算机模拟结果得出的结论是，在 UST 下 Ti 的结构转变发生在比 Ni 高得多的应力下，

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