Transmission Electron Microscopy
Transmission Electron Microscopy
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透射电子显微镜
DOI：
10.1007/978-3-319-26651-0_3
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Burke M
中科院分区：
文献类型：
--
作者：
Burke M
在许多材料体系中，特别是在金属和合金体系中，可以存在几种不同的相。对于工程材料尤其如此，如钢和高温合金，其中我们从各种第二相的存在、分布和特定的相对取向中获得所需的性能。虽然我们可以通过单晶衍射图（例如，通过CBED或微衍射）来识别相的结构，但相的or也可以提供非常有用的信息。例如，我们可以进行相识别，辨别相在微观结构中的分布，以及形成的顺序。您在《W&C》第18章中看到，相之间的or（特别是在母体/矩阵和第二相/转换产物之间）通常是我们获得支持相识别和理解相形成机制的证据的方式。当我们对材料进行表征时，不仅要确定组成相，而且要评估相的大小和分布，这对我们来说往往很重要。当感兴趣的相与基体或母相表现出or时，我们可以很容易地形成具有共同取向的所有（或大多数）第二相（或沉淀）的衍射对比图像。
In many materials systems, particularly in metals and in alloy systems, several different phases can be present. This is especially true for engineering materials, such as steels and superalloys, wherein we obtain the desired properties from the presence, the distribution, and the specific relative orientations of the various second phases. Although we can identify the structure of phases through single-crystal diffraction patterns (eg, via CBED or microdiffraction), the OR relating the phases can also provide very useful information. For example we can carry out phase identification and discern the distribution of phases within the microstructure, as well as the sequence of formation.You saw in Chap. 18 of W&C that the ORs between phases (particularly between a parent/matrix and a second phase/transformation product) are frequently the way that we can gain evidence to support phase identification and to understand the mechanisms of phase formation. When we characterize materials it is often important for us not only to identify constituent phases, but also to assess the size and distribution of the phases. When the phases of interest exhibit ORs with either the matrix or parent phase, we can easily form diffraction-contrast images of all (or most) of the second phases (or precipitates) that share the common orientation.