Abstract The deformation-induced dilation of mineral-filled polyvinyl chloride (PVC) is investigated by means of polychromatic X-ray absorption tomography (XCT). Axisymmetric notched tensile specimens are strained to prescribed elongations using a tensile test apparatus and subsequently scanned by XCT after relaxation. During straining, surface deformations are quantified by digital image correlation (DIC) and contour tracking. The influence of stress triaxiality and strain rate on dilation is investigated by using tensile specimens with three different notch radii, all strained to three deformation levels at two different nominal strain rates. Pronounced reduction of density, corresponding to an increase of volume, is observed for all specimens in the XCT scans, but markedly different relative density distributions are measured for the three geometries. The accuracy of the polychromatic XCT density estimates is evaluated against data obtained with monochromatic synchrotron radiation computed tomography (sr-XCT), and a comparison to surface deformation-based dilation estimates is presented.

中文翻译：

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X射线计算机断层扫描研究单调载荷下矿物填充PVC的膨胀

摘要 通过多色X射线吸收断层扫描（XCT）研究了矿物填充聚氯乙烯（PVC）的变形引起的膨胀。使用拉伸试验装置将轴对称缺口拉伸试样应变至规定的伸长率，然后在松弛后通过 XCT 进行扫描。在应变期间，表面变形通过数字图像相关 (DIC) 和轮廓跟踪进行量化。通过使用具有三个不同缺口半径的拉伸试样研究应力三轴性和应变速率对膨胀的影响，所有试样在两个不同的标称应变速率下都应变到三个变形水平。在 XCT 扫描中观察到所有标本的密度显着降低，对应于体积的增加，但是对于三种几何形状测量的相对密度分布明显不同。多色 XCT 密度估计的准确性根据单色同步辐射计算机断层扫描 (sr-XCT) 获得的数据进行评估，并与基于表面变形的膨胀估计进行比较。