Effect of dynamic recrystallization on texture orientation and grain refinement of Ti6Al4V titanium alloy subjected to laser shock peening
Effect of dynamic recrystallization on texture orientation and grain refinement of Ti6Al4V titanium alloy subjected to laser shock peening
复制标题
动态再结晶对Ti6Al4V钛合金激光冲击喷丸织构取向及晶粒细化的影响
DOI：
10.1016/j.jallcom.2020.156672
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发表时间：
2021-01-05
影响因子：
6.2
通讯作者：
Zhou, Liucheng
中科院分区：
文献类型：
--
作者：
Pan, Xinlei;Wang, Xuede;Zhou, Liucheng
利用电子背散射衍射仪(EBSD)和透射电子显微镜(TEM)对Ti6Al4V钛合金激光冲击强化(LSP)后的动态再结晶(DRX)机制及其对织构取向和晶粒细化的影响进行了系统的研究。结果表明，剪切带诱导的DRX机制在LSP织构转变和细化过程中起着至关重要的作用。根据观察结果，确定DRX机制为连续动态再结晶(CDRX)。由于剪切带内大范围的局部取向偏差，新的动态再结晶晶粒表现出[(1)对棒2(1)对棒0]取向的优先选择，从而导致原始[01(1)对棒0]纤维成分的弱化。在LSP过程中，变形主要由α相中的基面滑移和锥体滑移支撑，为后续的CDRX过程激活大量非基面位错。靠近表面的形核位置越多，以及超高应变速率变形引起的绝热温度升高，都有助于提高DRX，从而导致顶部表面更强烈的晶粒细化。(C)2020爱思唯尔B.V.保留所有权利。
In this paper, using electron backscatter diffraction (EBSD) and transmission electron microscope (TEM) characterization, we systematically investigated the dynamic recrystallization (DRX) mechanism and its effects on the texture orientation and grain refinement of Ti6Al4V titanium alloy subjected to laser shock peening (LSP). The results indicated shear bands-induced DRX mechanism played a vital role in texture transition and grain refinement during LSP. Based on the observation, the DRX mechanism was determined as continuous dynamic recrystallization (CDRX). Due to the wide range of local misorientation of grains within shear bands, the new dynamic recrystallized grains exhibited preferred selection of [(1) over bar 2 (1) over bar 0] orientation, thereby resulting in the original [01 (1) over bar0] fiber component weakening. The deformation is mainly supported by basal slip and pyramidal slip in alpha phase during LSP, activating massive non-basal dislocation for the subsequent CDRX process. The more nucleation sites available closer to the surface, as well as the increasing adiabatic temperature induced by ultra-high strain rate deformation there, contributed to the improved DRX, resulting in more intense grain refinement on the top surface. (C) 2020 Elsevier B.V. All rights reserved.