EB炉流程纯钛的热变形和动态再结晶行为研究

Study on hot deformation and dynamic recrystallization behavior of pure titanium in EB furnace process

摘要:

通过热压缩实验研究了原始晶粒尺寸为厘米级的EB炉流程纯钛在不同变形温度和变形速率下的热变形行为,并基于电子背散射衍射(EBSD)技术对EB炉流程纯钛的再结晶机制进行了探讨。结果表明：厘米级的EB炉流程纯钛在热变形过程中的加工硬化行为具有典型的“三阶段”特征：第一阶段线性快速下降；第二阶段迅速回升至一个峰值；第三阶段从峰值又开始下降,这与变形过程中的孪生现象有关；EBSD结果表明超粗晶粒纯钛在热变形过程中的再结晶机制主要是非连续动态再结晶。

Abstract:

The hot deformation behavior of pure titanium in EB furnace process (EB-Ti) with centimeter scale original grain size at different deformation temperature and deformation rate was studied by thermal compression experiment, and the recrystallization mechanism of EB-Ti was discussed based on the electron back scattering diffraction (EBSD) technology. The results show that the hardening behavior of EB-Ti in the process of hot deformation has typical "three-stage" characteristics. In the start stage, the hardening ability is rapid linearly declined; in the middle stage, it rapidly recovers to a peak; in the final stage, it re-declines from the peak. The three-stage phenomenon is related to twinning in the deformation process. EBSD results also show that the recrystallization mechanism of EB-Ti in the process of hot deformation is mainly a discontinuous dynamic recrystallization.