热塑性定型剂对干铺丝-RTM工艺及力学性能影响

Influence of thermoplastic tackifier on dry fiber placement-RTM process and mechanical properties

为了研究热塑性定型剂的添加对干铺丝-树脂传递模塑(RTM)工艺的影响,采用PA-6作为热塑性定型剂,通过T-剥离确定定型剂的质量分数,结合试验和工艺仿真,研究了定型剂对预制体面内渗透率的影响,并对其充模过程进行工艺仿真和分析,在此基础上研究了定型剂对环氧复合材料制品层间性能及韧性的影响。渗透率试验和仿真结果表明:加入定型剂后,纤维预制体的沿纤维和垂直纤维的面内渗透率分别降低了55.5%和52.0%;工艺仿真结果与试验结果一致,不同渗透长度下的注胶时间偏差均小于10%。力学性能试验结果表明:加入热塑性定型剂可显著提升环氧树脂复合材料的韧性,Ⅰ型和Ⅱ型层间断裂韧性分别提高了89.3%和54.1%,冲击韧性提高了18.7%,复合材料的层间剪切强度降低了23.6%。

In order to study the effect of thermoplastic tackifier addition on the dry fiber placement-RTM(resin transfer molding)process,T-peel test was utilized to determine the mass fraction of PA-6 tackifier.Combining the test with process simulation,the effect of tackifier on the in-plane permeability of preform with PA-6 as the tackifier was studied.The mold filling process was stimulated and analyzed.On this basis,the influence of tackifier on the interlaminar properties and toughness of epoxy composites was studied.The test and simulated results of permeability of preform with tackifier showed that the permeability of fiber preform in parallel with and perpendicular to fiber direction reduced by 55.5%and52.0%,respectively.The test results were consistent with the revised simulated results,and the deviation values of filling time with different penetration distances were all smaller than 10%.The results of mechanical test showed that the toughness of epoxy composites could be enhanced significantly by adding thermoplastic tackifier.The modeⅠandⅡinterlaminar fracture toughness improved by 89.3%and 54.1%,respectively.While the impact toughness improved by 18.7%,the interlaminar shear strength reduced by 23.6%.