Strain resolution of scanning electron microscopy based Kossel microdiffraction
Strain resolution of scanning electron microscopy based Kossel microdiffraction
复制标题
基于科塞尔微衍射的扫描电子显微镜应变分辨率
DOI：
10.1107/s1600576714019402
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发表时间：
2014
影响因子：
6.1
通讯作者：
E. Patoor
中科院分区：
文献类型：
--
作者：
D. Bouscaud;A. Morawiec;R. Pesci;S. Berveiller;E. Patoor
扫描电子显微镜中的科塞尔微衍射可以确定局部弹性应变。通过 CCD 相机记录的科塞尔图案和应变测定过程的一些自动化，该技术可能成为应变分析的便捷工具。对于所有应变测定方法，科塞尔技术适用性的关键在于其应变分辨率。分辨率可以通过多种方式进行估计：从基于模拟图案（镍合金）的最简单测试，通过分析Ge的尖锐实验图案，到通过镍基高温合金单晶的原位拉伸应变获得的估计值。在后一种情况下，将结果与传统 X 射线衍射和基于同步加速器的科塞尔衍射的结果进行了比较。在高质量 Ge 图案的情况下，所有应变张量分量的分辨率均达到 1 × 10−4；这相当于约 10 MPa 的应力。应变镍基高温合金具有相对扩散的图案，在平面应力假设下，应变和应力分辨率分别为 3 × 10−4 和 60 MPa。描述了实现这些分辨率的实验和计算条件。该研究显示了半自动科塞尔微衍射作为局部应变测定方法的潜在应用前景和局限性。
Kossel microdiffraction in a scanning electron microscope enables determination of local elastic strains. With Kossel patterns recorded by a CCD camera and some automation of the strain determination process, this technique may become a convenient tool for analysis of strains. As for all strain determination methods, critical for the applicability of the Kossel technique is its strain resolution. The resolution was estimated in a number of ways: from the simplest tests based on simulated patterns (of an Ni alloy), through analysis of sharp experimental patterns of Ge, to estimates obtained by in situ tensile straining of single crystals of the Ni-based superalloy. In the latter case, the results were compared with those of conventional X-ray diffraction and synchrotron-based Kossel diffraction. In the case of high-quality Ge patterns, a resolution of 1 × 10−4 was reached for all strain tensor components; this corresponds to a stress of about 10 MPa. With relatively diffuse patterns from the strained Ni-based superalloy, under the assumption of plane stress, the strain and stress resolutions were 3 × 10−4 and 60 MPa, respectively. Experimental and computational conditions for achieving these resolutions are described. The study shows potential perspectives and limits of the applicability of semiautomatic Kossel microdiffraction as a method of local strain determination.