标题：Electron backscattered diffraction analysis of the effect of deformation temperature on the microstructure evolution in a typical nickel-based superalloy during hot deformation
作者：Qin, Shengxue; Zhang, Hongbin; Liu, Jie; Zheng, Wei
作者机构：[Qin, Shengxue; Zhang, Hongbin; Liu, Jie] Shandong Univ Sci & Technol, Coll Mech & Elect Engn, Qingdao 266590, Peoples R China.; [Zheng, Wei] Shando 更多
通讯作者地址：[Zhang, HB; Liu, J]Shandong Univ Sci & Technol, Coll Mech & Elect Engn, Qingdao 266590, Peoples R China.
来源：JOURNAL OF MATERIALS RESEARCH
摘要：The microstructure evolution of a typical nickel-based superalloy was studied in the temperature range of 960-1160 degrees C with the strain rate of 0.001 s(-1) by using electron backscattered diffraction technique. Based on the grain orientation spread method, the dynamic recrystallization (DRX) grains were distinguished from the deformed grains. The results revealed that the volume fraction and the size of DRX grains increased with the increasing deformation temperatures. Most of the original Sigma 3 boundaries lost their twin characteristics due to crystal rotations during hot deformation. Meanwhile, lots of new Sigma 3 boundaries were formed in the DRX grains mainly by growth accidents. Moreover, the deformation temperature had a similar effect on the fraction of Sigma 3 boundary and the Sigma 3 boundary density in the DRX domains, which increased firstly and then decreased with the increasing deformation temperature. The Sigma 3 boundary density was analyzed as a function of grain size, and the critical grain size below which no twin forms was calculated to be 2.06 mu m. In addition, the coherent Sigma 3 boundaries were easier to form at the higher deformation temperature due to their lower boundary energy.