玻璃纤维增强复合材料的Ⅰ型层间断裂韧性

MODE I INTERLAMINAR FRACTURE TOUGHNESS OF GLASS WOVEN FABRIC REINFORCED COMPOSITES

介绍了玻璃纤维增强复合材料Ⅰ型层间断裂韧性“RoundRobinTest”的结果随着偶联剂浓度的改变，Ⅰ型裂纹的扩展方式从稳态向非稳态转变这类断裂韧性强烈地依赖界面性能关键词##4界面性能;;Ⅰ型断裂韧性;;裂纹扩展;;稳态;;

Mode I interlaminar fracture toughness tests were carried out with glass stain wovenfabric vinylester composites, which were treated by several difFerent kinds of coupling agent, in orderto identify the relation betWeen interface properties and fracture behavior. Crack growth behavior wasstrongly dependent on the interface properties. The crack growth behavior of the composites changesfrom stable to unstable manners with increasing silane coupling agent. Unstable fracture occurs in thecase of high concentration of silane coupling agent. If the crack reaches a tougher region, it slows downuntil the stored elastic energy becomes sufficient to propagate the crack through the tougher region.The reason for forming tougher region in composites is that different kinds of silane coupling agentused for treating glass fibres can change the chemical structure of vinylester resin.Bare glass fibres were exposed on stable fracture surface without resin. The characteristics offracture surface will change, when the crack propagation changes from stable to unstable. Some resinadhere on glass fibers and the proportion of resin adhered to the surface rapidly increases with increasingcrack growth. The whole fracture surface was covered by resin and no glass fiber strand was found onthe surface. This corresponds to unstable fracture.