丁羟四组元推进剂老化过程中力学性能表征试验研究

The structural integrity of solid propellant is very important for the storage life evaluation of solid rocket motor,and the mechanical properties of solid propellant during aging must be analyzed.The accelerated aging mechanism of four-component HTPB propellants at 60 ℃ was studied,and the maximum elongation,tensile strength,initial modulus and “dewetting”strain threshold at 20 ℃,60 ℃ and -40 ℃,and surface hardness at 20 ℃ were obtained.Furthermore,the relationship between characterization parameters of mechanical properties at 20 ℃ and surface hardness,as well as correlation of mechanical properties characterization parameters at 60 ℃ and -40 ℃ with those at 20 ℃ were investigated.The results show that:(1)RDX do not have a significant effect on the aging of the four-component HTPB propellant.(2)During the aging process,there exists a significant positive correlation between the tensile strength of the propellant at 20 ℃ and the surface hardness,as well as a significant positive correlation between the tensile strength at 60 ℃ or -40 ℃ and the tensile strength at 20 ℃.(3)During the aging process,there is no obvious correlation between the “dewetting” strain threshold at 60℃ or -40 ℃ and the “dewetting” strain threshold at 20 ℃ for the four-component HTPB propellant.Taking the“dewetting”strain threshold as fixed values,the ratio of 60 ℃ to 20 ℃ is 1.93,while the ratio of -40 ℃ to 20 ℃ is 0.33.