Data from: An experimental study on the manufacture and characterisation of in-plane fibre-waviness defects in composites

A new method has been developed for creating localised in-plane fibre-waviness in composite coupons and used to create a large batch of specimens. This method could be used by manufacturers to experimentally explore the effect of fibre-waviness on composite structures both directly and indirectly to develop and validate computational models. The specimens were assessed using ultrasound, digital image correlation and a novel inspection technique capable of measuring residual strain fields. To explore how the defect affects the performance of composite structures, the specimens were then loaded to failure. Predictions of remnant strength were made using a simple ultrasound damage metric and a new residual strain-based damage metric. The predictions made using residual strain measurements were found to be substantially more effective at characterising ultimate strength than ultrasound measurements. This suggests that residual strains have a significant effect on the failure of laminates containing fibre-waviness and that these strains could be incorporated into computational models to improve their ability to simulate the defect.

本研究开发了一种可在复合材料试样（composite coupons）中制备局部面内纤维波状缺陷（fibre-waviness）的方法，并利用该方法制备了大批量试样。该方法可供制造商通过直接与间接的实验手段，探究纤维波状缺陷对复合材料结构的影响，以此开发并验证计算模型。研究采用超声检测、数字图像相关（digital image correlation）技术以及一种可测量残余应变场的新型检测方法，对所制备的试样进行了表征评估。为探究该缺陷对复合材料结构力学性能的影响，研究人员对所有试样开展了载荷加载直至失效的力学测试。研究团队分别采用简易超声损伤指标与新型基于残余应变的损伤指标，对试样的剩余强度进行了预测。结果表明，相较于超声检测方法，基于残余应变测量的预测结果在表征极限强度方面表现更为优异。该结果证实，残余应变对含纤维波状缺陷的层合板失效过程具有显著影响，且可将此类应变纳入计算模型，以提升模型对该缺陷的模拟精度。