Excitation of thermal dissipation of solid propellants during the fatigue process

• Published in: Materials & design 2017-08, Vol.128, p.47-55
• Main Authors: Tong, Xin, Chen, Xiong, Xu, Jinsheng, Sun, Chaoxiang, Liang, Wei
• Format: Article
• Language: English
• Subjects: Fatigue; Heat dissipation; Infrared thermography; Solid propellants; Stored energy
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2017.04.088

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. [Display omitted] •Mechanical loss and heat dissipation of solid propellant during fatigue are detectable using mechanical and thermal data.•Two stages of temperature evolution were observed during finite cyclic loadings for solid propellant.•Localization of temperature rise during fatigue indicated the weakest area of solid propellant.•Proposed method allows acquisition of stored energy at different stages of cyclic loading.