压电阻抗法表征固体推进剂老化的研究

Research on Aging Characterization of Solid Propellantsby Electro-Mechanical Impedance

关键词:  压电阻抗法  固体推进剂  热老化  机械阻抗  动态热机械分析  动态力学性能

Key words:  Electro-mechanical impedance  Solid propellant  Thermal aging  Mechanical impedance  Dynamic thermomechanical analysis  Dynamic mechanical properties

摘要:

为了更好地得到压电阻抗法（EMI, Electro-mechanical impedance）监测固体推进剂老化规律并从物理特性上对其科学性、可靠性及有效性进行验证，采用理论推导分析方法将压电阻抗电学性能参数与动态力学性能参数进行联系；对热老化HTPB推进剂进行EMI试验及动态热机械分析（DMA, Dynamic thermomechanical analysis）测试，并根据结果分析进行验证。结果表明：压电阻抗电学性能与动态力学性能能够通过动态模量与导纳之间的关系以及电压电流滞后角与力学损耗角之间的关系进行联系；热老化HTPB推进剂在不同测试频率下力学损耗因子温度谱峰值随老化的变化规律一致，均随热老化时间的延长而降低；电压电流滞后角正切值能够很好反映HTPB推进剂的老化，共振频率处的滞后角正切值随热老化时间的延长而降低，并且与损耗因子峰值呈现出明显的线性关系。

Abstract:

In order to obtain the aging rule of solid propellant better by EMI (Electro-mechanical impedance), and verify its scientific, reliability and validity from its physical characteristics, the parameters of electro-mechanical impedance proper ties and dynamic mechanical properties were correlated by theoretical derivation and analysis method. EMI and dynamic thermomechanical analysis (DMA) tests were carried out on HTPB propellant specimens with thermal aging, and the results were verified by the analysis. The results show that the electrical properties and dynamic mechanical properties of piezoelectric impedance can be related by the relationship between dynamic modulus and admittance, and the relationship between voltage-current lag angle and mechanical loss angle. The temperature spectrum peak value of loss factor of HTPB propellant varies with aging time at different testing frequencies, and the peak value decreases with the prolongation of thermal aging time. The tangent value of voltage and current lag angle can well reflect the aging of HTPB propellant. The tangent value of lag angle at resonance frequency decreases with the prolongation of thermal aging time, and it has obvious linear relationship with the peak value of loss factor .