Said Meena, Eng Charlotte W, Hixon Amy E, Marks Naomi E
Nuclear & Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA; Department of Civil & Environmental Engineering & Earth Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA.
Nuclear & Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA.
Forensic Sci Int. 2020 Nov;316:110470. doi: 10.1016/j.forsciint.2020.110470. Epub 2020 Aug 22.
Rapid, non-destructive nuclear forensic techniques can aid in signature development and provide valuable information for provenance assessments. Using optical profilometry and digital microscopy, we studied the surface roughness of fuel pellets to probe its usefulness as a forensic signature and its relationship to a given producer's grinding techniques. Arithmetic average areal (S) surface roughness measurements provide a rapid, non-destructive technique, producing efficient measurements with smaller standard uncertainties relative to 2D, arithmetic average profile (R) surface roughness measurements. Digital microscopy proved to be the superior technique over optical profilometry, in part due to its higher image quality, faster data acquisition capabilities, and multi-purpose potential in physical surface characterization. Using digital microscopy, fuel pellet S surface roughness varies in commercial reactor fuel pellets from 1.54±0.17μm to 2.11±0.12μm and does not appear to depend solely on the use of wet versus dry grinding techniques. Populations of pellets produced at three different commercial reactor fuel production facilities were distinguishable on the basis of S. Complementary to other key forensic characteristics, such as dimensions and enrichment, S measurements provide a promising nuclear forensic signature for sintered UO fuel pellets.
快速、无损的核法医技术有助于特征开发，并为来源评估提供有价值的信息。我们使用光学轮廓测量法和数字显微镜，研究了燃料芯块的表面粗糙度，以探究其作为法医特征的有用性及其与特定生产商研磨技术的关系。算术平均面粗糙度（S）测量提供了一种快速、无损的技术，与二维算术平均轮廓（R）表面粗糙度测量相比，它能以更小的标准不确定度进行高效测量。数字显微镜被证明是优于光学轮廓测量法的技术，部分原因在于其更高的图像质量、更快的数据采集能力以及在物理表面表征方面的多功能潜力。使用数字显微镜，商用反应堆燃料芯块的S表面粗糙度在1.54±0.17μm至2.11±0.12μm之间变化，似乎并不完全取决于湿磨与干磨技术的使用。在三个不同的商用反应堆燃料生产设施生产的芯块群体在S的基础上是可区分的。与尺寸和富集度等其他关键法医特征相辅相成，S测量为烧结UO燃料芯块提供了一个有前景的核法医特征。
