The fiber length distribution (FLD) is one of the factors that determine the mechanical properties of discontinuous carbon fiber reinforced plastic (CFRP). However, accurate sampling for FLD evaluation of CFRP is difficult because the homogeneity of CFRP for sufficient and measurable sample sizes is not always guaranteed and the carbon fibers in the evaluation specimens are easily broken. In this study, we presented a sampling method that extracts a sub-milligram-scale sample from the gram-scale quantity of carbon fibers. Based on the proposed method, filtration and a multi-stage sampling procedure were employed to prepare the sample. This method showed better precision compared to the sampling method of pulling the carbon fibers from the target with tweezers. Furthermore, our developed sampling method for FLD evaluation enabled the preparation of the sample representing a gram-scale quantity of the discontinuous carbon fibers.

中文翻译：

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测定纤维长度分布的碳纤维取样方法

纤维长度分布（FLD）是决定不连续碳纤维增强塑料（CFRP）力学性能的因素之一。然而，CFRP 的 FLD 评估的准确取样是困难的，因为对于足够且可测量的样品尺寸，CFRP 的均匀性并不总是得到保证，并且评估样品中的碳纤维很容易断裂。在这项研究中，我们提出了一种采样方法，可以从克级数量的碳纤维中提取亚毫克级样品。基于所提出的方法，采用过滤和多级采样程序来制备样品。与用镊子从目标上拉出碳纤维的取样方法相比，该方法显示出更好的精度。此外，