Inspired by metal forming tests, the conventional forming limit diagram (FLD) was employed to characterize the forming properties of the Glass Fiber Reinforced Polypropylene (GFRP) composite in this study. The strain history of GFRP specimens was captured by using a 3D digital image correlation (DIC) system. Since the conventional metal FLD is established by major and minor strains only, which is inadequate to characterize the formability of different components in the pre-consolidated woven composites. Therefore, this study proposes a new notch design, where the specimens have two long notches with different aspect ratios on the both sides, to ensure that the failure is dominated by fiber breakage mode while retaining the fiber continuity in specimens. For comparison, the conventional hourglass specimens and the newly-proposed notch specimens with different widths were both tested through a series of stamping experiments to investigate the formability of the GFRP materials. The equivalent fiber strains based FLD from the conventional narrow hourglass specimens with $\left({45}^{°},-{45}^{°}\right)$ shows an abnormal value of equivalent fiber strain around 40% in the shear deformation region, which was far beyond the tensile limit of glass fibers. On contrary, the FLD from the proposed notch specimens presented a limiting strains around 5%, involving all possible deformation modes. Thus, the FLD of the notch specimens was established in the form of parallel line here, which can be used as a criterion to characterize the formability of GFRP in which the fiber breakage was a dominant failure mode. Note that this criterion takes into account the influence of different components on the formability of GFRP and combined deformation history with failure mechanism, implying more suitable for GFRP. This study provided an effective way to establish the design criteria and FLD for other woven pre-consolidated GFRP materials.

受金属成型测试的启发，本研究采用常规成型极限图（FLD）来表征玻璃纤维增​​强聚丙烯（GFRP）复合材料的成型性能。通过使用3D数字图像相关（DIC）系统捕获GFRP标本的应变历史。由于常规金属FLD仅由主要和次要应变建立，因此不足以表征预固结机织复合材料中不同组件的可成形性。因此，本研究提出了一种新的缺口设计，即试样在两侧具有两个长宽比不同的长缺口，以确保破坏以纤维断裂模式为主导，同时保持试样中的纤维连续性。为了比较，常规的沙漏样品和新提议的具有不同宽度的缺口样品都通过一系列冲压实验进行了测试，以研究GFRP材料的可成型性。常规窄沙漏样品中基于等效纤维应变的FLD与$\left({45}^{°}，--{45}^{°}\right)$在剪切变形区域显示出等效纤维应变的异常值在40％左右，这远远超出了玻璃纤维的拉伸极限。相反，拟议的缺口试样的FLD呈现出约5％的极限应变，涉及所有可能的变形模式。因此，在这里以平行线的形式建立了缺口试样的FLD，这可以用作表征GFRP的可成形性的判据，其中纤维断裂是主要的破坏模式。请注意，该标准考虑了不同组件对GFRP成形性的影响以及变形历史与破坏机制的结合，这意味着更适合GFRP。这项研究为建立其他编织的预固结GFRP材料的设计标准和FLD提供了有效的方法。