Abstract Dynamic mechanical analysis is a technique used to determine the viscoelastic properties of polymers and their composites. The storage modulus, loss modulus and loss factor in correlation with the glass transition temperature can be detected by several means. In this study, these properties are determined using a dynamic mechanical analyzer in 3-point bending mode, as well as a rheometer in torsion mode. The materials under consideration are a unidirectional glass fiber-reinforced epoxy, a quasi-isotropic carbon fiber-reinforced epoxy and a quasi-isotropic glass fiber-reinforced epoxy. The results of each method and material are presented and the advantages and limitations of each method are discussed. 3-point bending proved to be more suitable to detect the effect of fiber orientation for unidirectional fiber-reinforced epoxy but requires careful control of sample dimensions for accuracy. Torsion, on the other hand, gave consistent measurements for samples of varying lengths, proving to be a suitable method if materials are scarce and limited.

中文翻译：

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测定纤维增强环氧树脂粘弹性的三点弯曲法和扭转法的比较

摘要 动态力学分析是一种用于确定聚合物及其复合材料粘弹性性能的技术。可以通过多种方式检测与玻璃化转变温度相关的储能模量、损耗模量和损耗因子。在这项研究中，这些特性是使用动态力学分析仪在 3 点弯曲模式下以及在扭转模式下使用流变仪来确定的。所考虑的材料是单向玻璃纤维增​​强环氧树脂、准各向同性碳纤维增强环氧树脂和准各向同性玻璃纤维增​​强环氧树脂。介绍了每种方法和材料的结果，并讨论了每种方法的优点和局限性。事实证明，3 点弯曲更适合检测单向纤维增强环氧树脂的纤维取向影响，但需要仔细控制样品尺寸以确保准确性。另一方面，扭转对不同长度的样品进行了一致的测量，如果材料稀缺且有限，则证明是一种合适的方法。