摘要
目的掌握聚醚推进剂在温度循环与应变耦合作用下的老化机理。方法开展65~75℃温度循环和3%预应变耦合作用下的老化试验,针对不同老化时间的聚醚推进剂,分析抗拉强度、伸长率等力学性能的变化规律,以及表面微观损伤、分子官能团、反应热等微观损伤演变情况,综合推断聚醚推进剂宏观-微观关联老化机理。结果随着老化时间延长,最大抗拉强度波动下降,最大伸长率先增大、后减小;高氯酸铵和聚醚粘合剂的分解峰温均向低温方向移动,位于1410 cm^(-1)的高氯酸铵吸收峰增强,而位于1565、1725 cm^(-1)的聚醚粘合剂中氨基甲酸酯、酰胺基团吸收峰下降;嵌在聚醚粘合剂内部的高氯酸铵逐渐暴露,且部分高氯酸铵颗粒与周围界面明显分离,并出现小孔洞。结论在长期温度循环和预应变作用下,聚醚推进剂分子主链中酰胺基团的C—N键由于分子间结合力较弱而分解断链,破坏了分子主链网状交联结构,使得分散其中的AP粒子逐渐露出表面,并呈现部分断裂损伤特征,引起抗拉强度下降。
In order to master the aging mechanism of polyether propellant under the coupling effect of temperature cycle and strain,the author of this paper carried out aging test of polyether propellant under 65℃~75℃ temperature cycle and 3% pre-strain.For polyether propellants with different aging times,this paper analyzes the variation rule of mechanical properties,such as tensile strength,elongation,and the microscopic damage evolution,such as surface microscopic damage,molecular functional groups and heat of reaction.At last,the macro-micro correlation aging mechanism was comprehensively inferred by the above data.With aging time prolonged,the maximum tensile strength showed declined fluctuation.The maximum elongation first increased and then decreased.Both the peak of decomposition temperature of ammonium perchlorate and polyether binder moved toward low temperature.The absorption peak of ammonium perchlorate at 1410 cm^(-1) was enhanced,while the absorption peak of carbamate at 1565 cm^(-1) and amide groups at 1725 cm^(-1) were decreased.The ammonium perchlorate embed-ded in the polyether binder was gradually exposed,and the separation between part of ammonium perchlorate particles and the surrounding was obvious.Meanwhile,there were small pores.Under the influence of long-term temperature cycle and pre-strain,the C-N bond of amide groups in the polyether propellant broke due to weak intermolecular binding force,and the reticular cross-linking structure of the chain was damaged,which made the dispersed AP particles gradually expose out of the surface and showed the characteristics of partial fracture damages,resulting in the decrease of tensile strength.
作者
赵方超
魏小琴
李晗
尹胜杰
李泽华
黄文明
ZHAO Fang-chao;WEI Xiao-qin;LI Han;YIN Sheng-jie;LI Ze-hua;HUANG Wen-ming(Southwest Institute of Technology and Engineering,Chongqing 400039,China;CSGC Key Laboratory of Ammunition Storage Environmental Effects,Chongqing 400039,China;Shanghai Space Propulsion Technology Research Institute,Shanghai 201109,China)
出处
《装备环境工程》
CAS
2021年第8期1-6,共6页
Equipment Environmental Engineering
基金
装备发展部维修技术研究项目(41404040301)。
关键词
聚醚推进剂
温度循环
预应变
老化机理
polyether propellant
temperature cycle
pre-strain
aging mechanism
