湿热环境下聚酰亚胺复合材料的拉脱性能研究

复合材料结构已被广泛应用于航空航天领域，为了研究复合材料在不同湿热环境下的力学性能，分别对低温干态（CTD）、室温干态（RTD）和高温湿态（ETW）三种环境下的某型聚酰亚胺复合材料层压板进行拉脱试验，并对RTD 试验过程进行仿真分析；通过试验获得两类典型铺层的拉脱强度与破坏模式，并利用有限元仿真预测失效载荷。结果表明：某型聚酰亚胺复合材料具有优异的热稳定性，CTD 环境下复合材料的拉脱强度较RTD 环境下的拉脱强度提升8.1%~9.0%，ETW 环境下某型聚酰亚胺复合材料的拉脱强度与RTD 环境下的拉脱强度相当；（30/60/10）铺层的拉脱强度略高于（50/40/10）铺层。

Research of Pull-through Properties of Polyimide Composites in Hygrothermal Environments

Composite structures have been widely used in the field of aerospace, in order to study the mechanical properties of composites in hygrothermal environments, the pull-through tests of a type of polyimide composite laminates were carried out under three test environments: cold temperature dry(CTD), room temperature dry (RTD) and elevated temperature wet (ETW). The numerical simulation analysis of the RTD test process was carried out. The pull-through strength and failure mode of two typical laminates were obtained by experimental, and the damage evolution process was qualitatively analyzed combined with the simulation results. The results show that the type of polyimide composites have excellent thermal stability. The pull-through strength of the composites under CTD condition is 8.1% ~ 9.0% higher than that under RTD condition, and the pull-through strength of the composites under ETW condition is equivalent to that under RTD condition. Compared with (40/50/10) ply, (30/60/10) ply has higher pull-through strength.