Cross-linking density and aging constitutive model of HTPB coating under prestrain thermal accelerated aging  

作　　者：Yong-qiang Du Jian Zheng Chao Xiong 

机构地区：[1]Shijiazhuang Campus,Army Engineering University,Shijiazhuang 050003,China

出　　处：《Defence Technology（防务技术）》2020年第2期439-446,共8页Defence Technology

基　　金：supported by the National Defense Pre-Research Foundation of China[grant number ZS2015070132A12002]。

摘　　要：In order to study the cross-linking density and aging constitutive relationship of HTPB coating during storage,the thermal accelerated aging tests at 0%,3%,6%and 9%prestrains were carried out.The crosslinking density of HTPB coating at different aging stages were tested using low-field^1 H NMR and the variation of cross-linking density was analyzed.The aging model of cross-linking density considering the chemical aging and the physical stretching factors was established.The uniaxial tensile tests were carried out on HTPB coating at different aging stages and the cross-linking density was introduced into Ogden hyperelastic constitutive model as a characterization parameter of correction coefficient.Combined with uniaxial tensile test results,a prestrain aging constitutive model of HTPB coating was established.The results show that the cross-linking density of HTPB coating increases rapidly at first and then slowly with the increase of thermal accelerated aging time without prestrain.Under prestrain conditions,the crosslinking density of HTPB coating decreases at the early stage,and increases rapidly at first and then slowly at the middle and late stages of thermal accelerated aging.The correlation coefficients of aging model of cross-linking density and aging constitutive model with test results are R>0.9500 and R>0.9900 respectively,which can be used to accurately describe the cross-linking density and aging constitutive relationship of HTPB coating under prestrain accelerated thermal aging conditions.

关 键 词：PRESTRAIN THERMAL accelerated AGING Low-field^1H NMR Cross-linking density AGING CONSTITUTIVE model 

分 类 号：V435[航空宇航科学与技术—航空宇航推进理论与工程]