Investigation of Relationships between Grain Structure and Inhomogeneous Deformation by Means of Laboratory-Based Multimodal X-Ray Tomography: Strain Accuracy Analysis
Investigation of Relationships between Grain Structure and Inhomogeneous Deformation by Means of Laboratory-Based Multimodal X-Ray Tomography: Strain Accuracy Analysis
复制标题
利用实验室多模态 X 射线断层扫描研究晶粒结构与不均匀变形之间的关系：应变精度分析
DOI：
10.1007/s11340-021-00701-0
复制
发表时间：
2021
影响因子：
2.4
通讯作者：
Miura H.
中科院分区：
文献类型：
--
作者：
Kobayashi M.;Zhang Y.;Ishikawa H.;Sun J.;Oddershede J.;Juul Jensen D.;Miura H.
背景塑性变形过程中的内部应变分布对于了解多晶材料的力学性能具有重要意义。这种分布可以通过微结构特征跟踪方法来确定。目的评价基于实验室多峰X射线层析测量的局部应变测量的准确性。方法采用吸收对比层析技术和衍射对比层析技术对含颗粒全再结晶Al-4mass%Cu合金在原位拉伸试验中的塑性变形行为进行表征。结果应变测量的精度与颗粒距离成反比，与颗粒尺寸无关，且不受晶界的影响。作为一个例证，微观结构-应变关系的初步分析揭示了单个颗粒之间和内部的显著应变差异。结论该结果证明了利用实验室X射线源进行局部应变测量的微观结构特征跟踪方法的有效性和局限性，对于局部应变分析具有普遍意义，可作为其他方法的替代方法，如数字图像相关法。通过这些测量，可以评估塑性变形过程中晶粒组织对局部应变发展的影响。通过对所选两个颗粒之间应变差异的初步分析，认为相邻颗粒之间的颗粒形状和结晶学关系对局部应变的发展是重要的。
BackgroundThe internal strain distribution developing during plastic deformation is important for understanding the mechanical properties of polycrystalline materials. Such distributions may be determined by the microstructural feature tracking method. However, the strain accuracy and the sources of uncertainty of this method are not well quantified yet.ObjectiveEvaluate the accuracy of local strain determination based on laboratory-based multimodal X-ray tomography measurements.MethodsThe plastic deformation behavior of a particle-contained fully recrystallized Al-4mass%Cu alloy was characterized during in-situ tensile testing using absorption contrast tomography to reveal marker particles and diffraction contrast tomography to reveal the grain structure.ResultsIt was found that the accuracy in strain measurement is inversely proportional to the particle distance, whereas it is independent of the particle size, and the accuracy is not biased by grain boundaries. As an illustrative example, the preliminary analysis of the microstructure-strain relationships reveals significant strain differences both between and within individual grains.ConclusionsThe results document the validity and limitations of the microstructural feature tracking method for local strain measurements using a laboratory X-ray source, are of importance for local strain analysis in general and may be considered as an alternative to other methods, e.g. digital image correlation. The measurements allow evaluation of effects of the grain microstructure on the local strain development during plastic deformation. By a preliminary analysis of the strain difference between two selected grains, it is suggested that the grain shape and crystallographic relationships between neighboring grains are of importance for the development of local strains.