A comprehensive study of the fibre breakage mechanisms during mould filling in injection moulding of short-fibre polymer composites requires the isolation of the main parameters promoting fibre length attrition. In this work, hydrodynamic parameters such as injection flow rate and residence time in the range of injection moulding were isolated, and their effect on fibre length attrition was studied. Fibre breakage was quantified by means of a capillary rheometer attached to an injection moulding machine minimising fibre-equipment interactions. Fibre breakage increased linearly as a function of injection flow rate in the range of 30–120 cm³.s⁻¹. It was also found that residence time in the order of milliseconds had a significant effect on fibre breakage. The results shown that longer fibres had less breakage probability, which contradicts the buckling failure theory for brittle fibres in a simple shear flow. This result was attributed to the similar rotation period of the fibres in comparison with the test residence times.

对短纤维聚合物复合材料的注模过程中模具填充过程中纤维断裂机理的全面研究要求隔离促进纤维长度磨损的主要参数。在这项工作中，流体动力学参数如注射流速和停留时间在注射成型范围内被分离出来，并研究了它们对纤维长度损耗的影响。借助于连接到注射成型机上的毛细管流变仪来定量纤维断裂，该毛细管流变仪使纤维-设备的相互作用最小化。在30–120 cm ³ .s ^-1范围内，纤维断裂与注入流量成线性关系。还发现停留时间在毫秒量级上对纤维断裂有显着影响。结果表明，较长的纤维断裂的可能性较小，这与简单剪切流中脆性纤维的屈曲破坏理论相矛盾。该结果归因于与测试停留时间相比，纤维具有相似的旋转周期。