Aging induced changes in the mechanical properties of solid propellant can lead to defects, such as cracks and grain–liner separations, which limit the service lifetime of solid rocket motors. This Paper presents an active sensing in situ identification method based on the electromechanical impedance technique, which is particularly suited for monitoring aging of solid propellants. This Paper first instructs a one-dimensional viscoelastic electromechanical coupling impedance model. A relationship between the dynamic modulus of solid propellants and its mechanical impedance is established. Then numerical calculation and experimental verification of the viscoelastic impedance model are conducted. Experimental research on aging monitoring of real solid propellant rocket and thermal accelerated aging hydroxyl-terminated polybutadiene solid propellant specimens are carried out. The results show that the real part of mechanical impedance curves decreases with the increase of aging time of solid propellants, and there is an approximate exponential relationship model between the peak value of real part of mechanical impedance and thermal accelerated aging time. It can be seen that the electromechanical impedance technique is an innovative method which can effectively characterize in situ the dynamic modulus of solid propellants, monitor the aging of solid propellants, and construct the aging life prediction model.

老化引起的固体推进剂机械性能变化会导致缺陷，例如裂纹和纹路分离，从而限制了固体火箭发动机的使用寿命。本文提出了一种基于机电阻抗技术的主动传感原位识别方法，特别适用于监测固体推进剂的老化。本文首先提出了一个一维粘弹性机电耦合阻抗模型。建立了固体推进剂的动态模量与其机械阻抗之间的关系。然后进行了粘弹性阻抗模型的数值计算和实验验证。进行了实心固体火箭的老化监测和热加速老化的羟基封端的聚丁二烯固体推进剂样品的试验研究。结果表明，机械阻抗曲线的实部随固体推进剂老化时间的增加而减小，并且机械阻抗实部峰值与热加速老化时间之间存在近似的指数关系模型。可以看出，机电阻抗技术是一种创新的方法，可以有效地原位表征固体推进剂的动态模量，监测固体推进剂的老化，并建立老化寿命预测模型。结果表明，机械阻抗曲线的实部随固体推进剂老化时间的增加而减小，并且机械阻抗实部峰值与热加速老化时间之间存在近似的指数关系模型。可以看出，机电阻抗技术是一种创新的方法，可以有效地原位表征固体推进剂的动态模量，监测固体推进剂的老化，并建立老化寿命预测模型。结果表明，机械阻抗曲线的实部随固体推进剂老化时间的增加而减小，并且机械阻抗实部峰值与热加速老化时间之间存在近似的指数关系模型。可以看出，机电阻抗技术是一种创新的方法，可以有效地原位表征固体推进剂的动态模量，监测固体推进剂的老化，并建立老化寿命预测模型。