定应变贮存条件下HTPB推进剂填料/黏合剂界面性能

为研究定应变贮存条件下HTPB推进剂的主要失效原因,基于单轴拉伸实验,得到HTPB推进剂的宏观力学性能。基于扫描电镜观察和测试探测液在填料AP,黏合剂基体上的接触角方法,表征了微观界面性能。实验结果显示,随老化时间的延长,最大延伸率显著降低,填料与黏合剂基体黏结变差,黏附功Wa减小,界面张力γsl增大。HTPB推进剂填料与黏合剂基体的界面黏结情况可由填料与黏合剂基体的黏附功、界面张力来表征。定应变作用下推进剂老化后黏附功的值远低于无应变热老化的值,界面张力的值远高于无应变热老化的值,定应变的存在严重影响了推进剂填料/基体界面的黏结。宏观-微观性能的相关性研究表明,最大延伸率和黏附功存在线性相关关系,最大延伸率的降低主要由界面黏结的劣化引起的。

Interfacial property of the filler/binder matrix for HTPB propellant under constant strain

To investigate the main failure reason of HTPB propellant under constant strain,the macroscopical mechanical property,microscosmic interfacial properties and their relationship were studied.The macroscopical mechanical properties were measured by uniaxial tensile testing.The microscosmic interfacial adhesive properties were characterized using Scanning Electron Microscope(SEM) and measuring the contact angle between the test liquids and filler AP or binder matrix.The results show that the maximum elongation are decreased,the interfacial adhesive between the filler and binder matrix are deteriorated,the work of adhesion(Wa) are decreased and the interfacial tension(γsl) increased along with the aging time.The interfacial adhesive property between the filler and binder matrix of HTPB propellant can be characterized by Wa and γsl.The value of the work of adhesion under constant strain is lower,and the interfacial tension is higher than that under zero strain.The existence of the constant strain has influenced the interfacial adhesive between the filler and binder matrix badly.The result shows that there is linear correlation between the maximum elongation and the work of adhesion.The decline of the maximum elongation is caused by the deterioration of the interfacial adhesive property.