Integrated solution for lokal, electron channeling based stress and strain measurement in the scanning electron microscope (εpsilator.X3)

许多材料的性能源于它们的纳米和微观结构。虽然这些材料的几何结构可以用已经建立的方法在宏观、微观和纳米水平上进行表征，但许多领域的局部性质可以在宏观水平上确定，但只能在微观水平上部分确定。特别是局部的机械应力和变形还需要花费大量的设备，例如同步加速器中的XRD，可以在微纳米尺度上测量，具有足够的可靠性和空间精度。但对于微观结构的发展和表征，它们是相当有趣的。近年来，大量的电子显微镜局部变形分析的新方法被开发和增强，尽管这些方法大多仍处于发展阶段。除了对SEM图像进行数字图像相关（DIC）外，一个主要的新方法是使用电子背散射衍射（EBSD）进行变形分析，特别是高分辨率（HR） EBSD。后者代表了DIC和EBSD的组合，并允许空间高分辨率，高精度地确定晶格的变形状态（应变和旋转），但到目前为止只能使用商业软件croscourt进行。此外，软件本身以及EBSD技术的性质也会产生某些问题。因此，该技术对流体静力应变不敏感，仅提供相对于局部参考点的变形数据。考虑到这些限制，本文所采用的方法适用于较老的选择区域信道（SAC）是有希望的。SAC以电子衍射图样的形式提供类似于EBSD的数据。然而，SAC提供了更高质量和角度分辨率的模式。这使得使用HR-EBSD方法进行更精确的变形测量成为可能。最初为EBSD模式开发的菊池带方法（KBM）的适应性进一步允许访问流体静力应变部件。此外，使用动态模拟图案作为参考点是可以想象的，这反过来又允许绝对变形测量。所有这些方法的关键是有效的模式索引，即相关晶体取向的确定和相关图像细节的识别。到目前为止，这只能通过相对较新的字典索引（DI）来实现。这里列出的方法在某种程度上是复杂的，并且计算量非常大，但是有很好的文档记录，并且在模式模拟和字典索引的情况下可以通过开放源码软件EMsoft访问。该项目旨在将这些方法结合起来，以超过以前基于SEM的方法的精度进行变形测量。为了对该工具进行必要的验证和校准，还将进行适当的实验。

The properties of many materials originate from their nano- and microstructure. While the geometric structures of these materials can be characterized by already established methods at the macro, micro and nano level, the local properties in many fields can be determined at the macro level but only partially at the micro level. Especially local mechanical stresses and deformations are not yet without great expenditure on equipment, e.g. XRD in the synchrotron, measurable on the micro and nano scale with sufficient reliability and spatial accuracy. But for microstructure development and characterization they are of considerable interest. In recent years, a large number of new methods for local deformation analysis in electron microscopy have been developed and enhanced, although most of these methods are still under development. In addition to digital image correlation (DIC) on SEM images, a major new methodology was the deformation analysis using electron back scatter diffraction (EBSD), in particular high-resolution (HR) EBSD. The latter represents a combination of DIC and EBSD and allows a spatially high resolved, highly accurate determination of the deformation state (strain and rotation) of the crystal lattice, but so far can only be performed using the commercial software CrossCourt. Additionally the software itself as well as the nature of the EBSD technology give rise to certain problems. The technique is therefore insensitive to hydrostatic strains and provides only deformation data relative to a local reference point. Regarding these limitations, the adaptation of the methods used here to the older selected area channeling (SAC) is promising. SAC provides data akin to EBSD in the form of electron diffraction patterns. However, SAC provides pattern in much higher quality and angular resolution. This enables more accurate deformation measurements with the methods underlying HR-EBSD. The adaptation of the Kikuchi bandlet method (KBM) originally developed for EBSD patterns further allows access to the hydrostatic strain parts. In addition, the use of dynamically simulated patterns as a reference point is conceivable which in turn allows absolute deformation measurements. Critical to all these methods is an effective indexing of the pattern, i.e. the determination of the associated crystal orientation and identification of relevant image details. Up to now, this has only been possible for SAC's patterns through relatively new dictionary indexing (DI). The methods listed here are in parts complex and computationally very intensive, but well documented and in the case of pattern simulation and dictionary indexing accessible via the open source software EMsoft. This Project aims to combine these methods to allow deformation measurement with an accuracy exceeding previous SEM based methods. For the necessary validation and calibration of this tool, suitable experiments will also be carried out.