Grabovetskaya Galina, Mishin Ivan, Stepanova Ekaterina, Zabudchenko Olga
Federal State Institution of Science, Institute of Strength Physics and Materials Science of the Siberian Branch of the Russian Academy of Sciences, 634055 Tomsk, Russia.
Division for Experimental Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia.
Materials (Basel). 2022 May 30;15(11):3905. doi: 10.3390/ma15113905.
In this paper, the effect of hydrogenation, in the amount of 0.15 wt.%, on the short-term creep of a titanium Ti-2.9Al-4.5V-4.8Mo alloy in fine-grained (FG) and ultrafine-grained (UFG) states is studied at 723 K. The UFG structure was formed by the method of pressing with the change of the deformation axis and gradual temperature decrease. Creep tests are performed under conditions of uniaxial tension at a constant load for the creep rates at an interval of (10 ÷ 10) s. The UFG alloy's resistance to creep under the investigated conditions is revealed to be substantially lower than in the FG state. When hydrogen presents in the alloy in a solid solution, a 1.3-2.5-fold rise in the value of the steady-state creep rate for the hydrogenated FG and UFG alloys is observed. The creep of the non-hydrogenated FG and UFG alloys is described by the creep power law. The presence of dissolved hydrogen leads to a violation of the creep power law. The values of stress sensitivity indices, steady-state creep rate, and effective creep activation energy are determined. The relationships between the hydrogenation, structure, and creep mechanisms of the alloy at the steady-state are discussed.
本文研究了在723K温度下，0.15重量%的氢化对细晶（FG）和超细晶（UFG）状态的钛Ti-2.9Al-4.5V-4.8Mo合金短期蠕变的影响。通过改变变形轴并逐渐降低温度的压制方法形成了超细晶结构。在单轴拉伸条件下，在恒定载荷下以（10÷10）秒的间隔对蠕变速率进行蠕变试验。结果表明，在所研究条件下，超细晶合金的抗蠕变性能明显低于细晶状态。当合金中存在固溶氢时，观察到氢化细晶和超细晶合金的稳态蠕变速率值提高了1.3至2.5倍。未氢化的细晶和超细晶合金的蠕变由蠕变幂律描述。溶解氢的存在导致蠕变幂律失效。确定了应力敏感指数、稳态蠕变速率和有效蠕变激活能的值。讨论了合金在稳态下氢化、结构和蠕变机制之间的关系。
