热老化改性双基推进剂拉伸力学性能及强度主曲线

Tensile Mechanical Properties and Strength Master Curve of Thermal Aged CMDB Propellant

为探讨老化高固含量改性双基推进剂(CMDB)的准静态拉伸力学性能,在四种温度(323,293,273,253 K)和不同应变率(3.3×10^(-5)、3.3×10^(-4)、3.3×10^(-3)、3.3×10^(-2) s^(-1))条件下,开展了CMDB推进剂单轴拉伸实验;对不同老化时间(0,10,20,35,50,65,80,100 d)的CMDB推进剂试样进行了气相色谱实验,研究了CMDB推进剂老化后的力学性能和中定剂含量的变化。结果表明,老化过程中最大伸长率和中定剂含量呈显著下降趋势,可以作为老化后的CMDB推进剂的失效判据。利用时间温度等效原理(TTSP),得到了CMDB推进剂最大抗拉强度主曲线,建立了老化强度主曲线方程,该方程可以在准静态应变率范围内对不同老化时间的CMDB推进剂的最大抗拉强度进行预估。

To investigate the quasi⁃static tensile mechanical properties of aging high solid content modified double⁃base propel⁃lants(CMDB),the uniaxial tensile tests of CMDB propellant were carried out at four different temperatures(323,293,273,253 K)and different strain rates(3.3×10^(-5),3.3×10^(-4),3.3×10^(-3),3.3×10^(-2) s^(-1)).The CMDB propellant samples with different ag⁃ing time(0,10,20,35,50,65,80,100 d)were tested by gas chromatography.The mechanical properties of CMDB propellant and the change of stabilizer content after aging were studied.The results show that the maximum elongation and the content of stabilizer decrease significantly during the aging process,which can be used as the failure criterion of the aging CMDB propel⁃lant.By using the time⁃temperature superposition principle(TTSP),the maximum tensile strength curve of CMDB propellant was obtained,and the aging strength main curve equation was established,which could be used to predict the maximum tensile strength of CMDB propellant with different aging time in the range of quasi⁃static strain rate.