Excitation of thermal dissipation of solid propellants during the fatigue process

Publication date: 15 August 2017
Source:Materials & Design, Volume 128
Author(s): Xin Tong, Xiong Chen, Jinsheng Xu, Chaoxiang Sun, Wei Liang
By using the infrared thermographic method, a non-destructive testing technique was applied to detect the surface-temperature evolution of solid propellants during strain-control fatigue tests within finite cycles. When the applied strains were below the viscoelastic limit, two stages of temperature variation were observed before the initiation of macroscopic cracks: an initial temperature-increase stage, and a steady temperature state. Thermodynamic analysis was carried out and a method was developed to allow the acquisition of stored energy at different stages of cyclic loading, which can reflect the material damage on the macroscopic scale. In addition, temperature localization during fatigue was observed, which implied the occurrence of damage accumulation and crack propagation. The results reveal that the cyclic-loading induced temperature increase of solid propellants during the fatigue process has a significant effect on solid rocket motors in a transportation or storage state.

Graphical abstract

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