Digital Volume Correlation (DVC), in concert with in situ Synchrotron Radiation Computed Tomography (SRCT), has been applied to Carbon-Fibre Reinforced Polymers (CFRPs) under quasi-static tensile loading. DVC represents a relatively novel tool for quantifying full-field volumetric displacements and implicit strain fields. The highly anisotropic and somewhat regular/self-similar microstructures found in well-aligned unidirectional (UD) materials at high volume fractions are shown to be intrinsically challenging for DVC, especially along the fibre direction. To permit the application of DVC to displacement and/or strain measurements parallel to the fibre orientation, the matrix was doped with a sparse population of sub-micrometre barium titanate particles to act as displacement trackers (i.e. fiducial markers). For the novel materials systems we have developed, measurement noise is considered along with the spatial filtering intrinsic to DVC data processing. Compared to volume images acquired through Micro-focus Computed Tomography (µCT), hold-at-load artefacts are mitigated through scan times on the order of seconds using SRCT, as opposed to hours. Instances of individually fractured fibres evolving into clusters of breaks are presented, together with the associated strain redistribution (imaged at a voxel resolution of 0.65 µm). It is shown that the distance over which strain is recovered in the broken fibres not only increases with the applied force, but also with the number of broken fibres, delineating aspects of the load shedding phenomenon. The study demonstrates that unprecedented, mechanistically-consistent three-dimensional (3D) strain measurements may be made in relation to fibre failure events, that can be used to validate micromechanical models for predicting UD tensile failure. We believe this work presents the first application of DVC to the SRCT imaging of failure in CFRPs, achieving significantly higher resolution than reported previously within the literature.

数字体积相关性（DVC）与原位同步辐射计算机断层扫描（SRCT）相结合，已在准静态拉伸载荷下应用于碳纤维增强聚合物（CFRP）。DVC代表了一种相对新颖的工具，用于量化全场体积位移和隐式应变场。在高度对齐的单向（UD）材料中，以高体积分数发现的高度各向异性和有些规则/自相似的微观结构对DVC尤其是沿纤维方向存在固有的挑战。为了允许DVC在平行于纤维取向的位移和/或应变测量中应用，基质中掺杂了稀疏的亚微米钛酸钡颗粒，以用作位移跟踪器（即基准标记）。对于我们开发的新型材料系统，考虑了测量噪声以及DVC数据处理固有的空间滤波。与通过微焦点计算机断层扫描（µCT）采集的体图像相比，使用SRCT可以在几秒的扫描时间内减少负载保持伪像，而不是几小时。给出了单个断裂的纤维演变成断裂簇的实例，以及相关的应变重新分布（以体素分辨率为0.65 µm成像）。结果表明，在断裂的纤维中恢复应变的距离不仅随着施加的力而增加，而且随着断裂的纤维的数量而增加，这表明了减载现象的各个方面。研究表明，前所未有的 可以针对纤维破坏事件进行机械一致的三维（3D）应变测量，可以用来验证用于预测UD拉伸破坏的微力学模型。我们相信这项工作将DVC首次应用于CFRP失效的SRCT成像中，实现了比以前文献中报道的更高的分辨率。