【摘要】 本文选用增韧 E-51 为基体分别与碳纤维、玻璃纤维和混杂纤维复合,测定了这两种复合材料的层间剪切强度、纵向冲击强度和层间断裂韧性。又通过扫描电镜观察断口形貌来研究增强材料与基体的界面粘结对复合材料力学性能的影响。研究结果表明增韧 E-51 基体在玻璃纤维表面形成一层厚度均匀的包复层。复合材料的破坏主要发生在包复层与基体之间,裂纹分枝多,G_c 值高,而碳/增韧 E-51中的碳纤维表面没有包复层,破坏发生在纤维与基体之间,裂纹分枝少,层间剪切强度与玻璃纤维复合材料相近而G_c值很低。 本文还对比了增韧E-51基体与F-46基体在界面粘接中的作用。研究结果表明,用玻璃纤维与F-46复合,界面粘结牢固,复合材料的层剪强度很高,G_c 值低。更多还原

【Abstract】 Three kinds of fibers including carbon fiber, glass fiber and their hybrid were ehosen as reinforcements in order to study their effect on fiber-matrix interfacial bonding and on mechanical properties of composites. Matrix used herein was toughened Epoxy E-51. Some mechanieal properties such as interlaminar shear strength,transverse tension strength, flexural strength, longitudinal impact strength and interlamiuar fracture toughness were measured, and fracture surface morphology was taken by using SEM. The experimental restilts showed that a homogeneous covering layer of Epoxy E-51 was coated sarroanding the glass fiber for glass fiber reiaforced composites and the failure in the composites was in form of erack propagating with more sub-eracks, which mainly occured between the covering layer and matrix. There was not, bowevor, any eover layer to form on the carbon surface for carbon composites, and cracks appeared on the fiber-matrix boundary. The interlaminar shear strength, flexural strength and transverse tension strength for carbon fiber composite were almost the same as those of glass fiber composite but its interlaminar fracture toughness and longitudinal impact strength were much lower than those of glass fiber composite, which could be improved by hybriding glass fiber. The conclusion had been verified by experimental results of glass and carbon fiber hybrid composites.For the purpose of comparison, Epoxy F-46 was introdued to estimate the effect of resins on boundary adhesion. The bonding behavior between glass and Epoxy F-46 was better than that between glass and Epoxy E-51. The short beam shear strength for Glass/ Epoxy F-46 composite was higher than that of Glass/Epoxy E-51 composite but the inlerlaminar fracture toughness was lower than that of Glass/Epoxy E-51 composites.更多还原