温度循环载荷对柔性接头界面损伤的影响

固体火箭发动机在生产、运输和储存的过程中会受到环境湿热和老化载荷的作用,导致柔性接头界面的力学性能产生退化.为研究柔性接头界面力学性能退化对界面损伤的影响规律,基于双线性内聚力模型建立了一种描述界面力学性能退化的数学模型.以某柔性接头为研究对象,为便于研究,以温度循环载荷代替环境老化载荷开展了界面损伤分析,并采用ABAQUS 6.14进行了仿真.结果 表明,与后法兰粘接的界面损伤程度最大.当温度循环周期达到672次时,界面13和界面14的损伤程度分别由初始状态的2.9％和4.3％增加到5.2％和8.2％,增幅分别高达81.2％和91.7％.同时,温度循环载荷会加速柔性接头的界面损伤.该界面力学性能退化模型可为柔性接头老化研究提供参考.

The effect of temperature cycling load on interfacial damage of flexible joint

A solid rocket motor receives the effect of environmental humidity,heat and ageing load during production,transportation and storage,which lead to degradation of the interface mechanical properties of its flexible joints.In order to study the influence law of interfacial degradation of the flexible joints on interfacial damage,one mathematical model describing interfacial degradation is established base on bilinear cohesive zone model.For ease of research,temperature cycling load instead of environmental ageing load is chosen as the external load in interfacial damage analysis,and the simulation is carried out with ABAQUS 6.14.Results indicate that the interface bonded to rear after flange has maximum damage.The interfacial damage of interface13 and interface14 has increased from 2.9% and 4.3% in the initial state to 5.2% and 8.2% respectively when the temperature cycle period reaches 672, an increase by up to 81.2% and 91.7%.Meanwhile,the temperature cycling load can accelerate the interfacial damage of the flexible joints.This degradation model of interface mechanical properties can provide a reference for the study of environmental ageing of flexible joints.