Polycrystal orientation mapping using scanning three-dimensional X-ray diffraction microscopy
Polycrystal orientation mapping using scanning three-dimensional X-ray diffraction microscopy
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DOI：
10.1107/s1600576715009899
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发表时间：
2015-08
影响因子：
6.1
通讯作者：
Y. Hayashi;Y. Hirose;Y. Seno
中科院分区：
文献类型：
--
作者：
Y. Hayashi;Y. Hirose;Y. Seno
提出了一种改进的三维X射线衍射（3DXRD）技术，以解决3DXRD型实验的主要问题，即多晶衍射斑点重叠。修改后的方法，称为扫描3DXRD，使三维晶体取向映射在多晶使用窄入射X射线束的光束尺寸充分小于平均晶粒尺寸。这种方法可以潜在地允许一个应用3DXRD类型的技术与大量的晶粒的标本。此外，由于使用远场区域检测器，扫描3DXRD为诸如应力台的设备提供了宽敞的样品环境，这在使用近场检测器的3DXRD方法中是不可行的。作为第一个演示，通过使用20 × 20 µm的光束和平均晶粒尺寸为60 µm的退火良好的铁样品的实验获得了三维取向图。扫描3DXRD与通过电子背散射衍射（EBSD）的取向图像显微镜相比相当好，考虑到在扫描3DXRD的情况下光束尺寸的影响。空间分辨率估计为约两倍的入射光束大小从扫描3DXRD重建模拟使用的EBSD取向图像上的样品建模的取向图。
A modified three-dimensional X-ray diffraction (3DXRD) technique is proposed as a solution to the main problem with 3DXRD-type experiments, namely, polycrystalline diffraction spot overlap. The modified method, termed scanning 3DXRD, enables three-dimensional crystallographic orientation mapping in polycrystals using a narrow incident X-ray beam with a beam size sufficiently smaller than the average grain size. This method can potentially allow one to apply a 3DXRD-type technique to specimens with a larger number of grains. Moreover, because of the use of a far-field area detector, scanning 3DXRD provides spacious specimen surroundings for equipment such as stress rigs, which are not feasible in 3DXRD methods using a near-field detector. As a first demonstration, a three-dimensional orientation map was obtained by an experiment using a 20 × 20 µm beam and a well annealed iron specimen with an average grain size of 60 µm. Scanning 3DXRD compared reasonably well with orientation image microscopy by electron backscatter diffraction (EBSD), considering the influence of the beam size in the case of scanning 3DXRD. The spatial resolution was estimated to be about twice the incident beam size from a scanning 3DXRD reconstruction simulation using an orientation map modeled on the EBSD orientation image of the specimen.