纯铁退火组织中特大晶粒三维拓扑与取向特征的定量研究

联合采用系列截面法和EBSD技术对含有特大晶粒的工业纯铁退火组织进行了三维重建和定量表征研究,重点分析了特大晶粒与普通晶粒之间的差异。三维重构的纯铁样品尺度为1920 μm×1219 μm×720 μm,包含12354个晶粒(其中有5个完整特大晶粒)。与以往三维重建的无晶体学取向信息的晶粒组织不同,本文三维重建的晶粒组织同时含有晶粒的三维几何形态信息和晶体学取向信息。研究结果表明,所研究的特大晶粒具有的界面个数为128~669(即最大晶粒同时具有高达669个邻接晶粒),其与相邻晶粒之间的平均取向差以及位于40°~55°区间的晶粒取向差明显大于普通晶粒之间的取向差。

Quantitative characterization of 3D topology and orientation features of exceptional big grains in annealed pure iron

Three-dimensional (3D) characterization of the microstructure containing exceptional big grains of industrial pure iron was carried out by means of serial sectioning, 3D reconstruction,and EBSD analysis. The differences between the exceptional big grains and the normal grains were analyzed in emphases. The dimensions of the 3D reconstructed pure iron sample are 1920 μm×1219 μm×720 μm, containing 12354 grains which includes5whole exceptional big ones. Different from previous reconstructed 3D grain microstructures without crystallographic orientation information,the present reconstructed 3Dgrains containsimultaneously both the geometric configuration information and the crystallographic orientation information of grains.The results show that the numbers of interfaces of the 5 exceptional big grains studied arein the range of 128-669 (i.e., the largest grain contacts simultaneously 669 neighboring grains). The average misorientation between the exceptional big grains and theirneighboring grains, and theirmisorientationwith their neighbors in the range of 40°-55°, are evidently higher than that between ordinary grains.