玻纤分布层合热塑性复合材料的力学性能及其失效行为

Mechanical Properties and Damage Behavior of Thermoplastic Composites with Glass Fiber Distribution-Layering Design

使用连续玻纤毡和玻纤网格布两种形态增强体,通过宏观不均匀增强体结构设计,在连续化运行的双钢带压机上制备得到了玻纤分布层合热塑性复合材料,探讨了玻纤增强体分布层合结构对复合材料力学性能及其失效破坏行为的影响。结果表明,玻纤增强体的宏观不均匀层合结构对复合材料的拉伸及弯曲性能的影响存在差异;连续玻纤毡位于外侧的分布层合结构能够抑制裂纹在垂直于拉力方向的扩展,层间分离的同时使更多的纤维束拔出断裂,显著改善了复合材料的拉伸性能;玻纤网格布位于外侧的分布层合结构则使其弯曲性能明显提高,外侧玻纤网格布中取向的玻纤呈现张力破坏使复合材料能够承受更高的弯曲载荷;分布层合结构中引入的玻纤网格布发挥了纤维束增韧作用,大幅提高了复合材料的冲击强度;与玻纤毡增强热塑料复合材料(GMT)相比,适宜的分布层合结构可使复合材料的拉伸及弯曲性能提高59%~76%、冲击强度提高53%。

Based on the macro heterogeneity reinforcement structure design, two different forms of continuous glass fiber mat and mesh were used to prepare the glass fiber distribution-layeringthermoplastic composites by the continuously running double-steel bett press machine. The influences of glass fiber distribution-layering structures on composite-mechanical properties and damage behavior were discussed. The results reveal that there is difference in improving the tensile and flexural properties withdifferent reinforcement distribution-layering structures. The outer side continuous glass fiber mat indistribution-layering structure reinforcement can not only restrain the development of haiis perpendicular to stress direction, but also induce layers peeling with extra pull-broken glass fibers, and thus enhances the tensile properties of composites significantly. On the other hand, the outer side glass fiber mesh in distribution-layering structure reinforcement provides oriented fibers bearing more force with tension failure mode,therefore improves the flexural properties significantly. Fiber bundles within themesh play a role of toughening, and largely increase the impact strength. Compared with glass fiber mat reinforced thermoplastics （GMT）, for the composites with appropriate distribution-layering structure the tensile and flexural properties can increase by 59%-76%,and the notched Izod impact strength can increase by 53% .