Investigating the coupled effects of temperature and strain rate for airship envelope composites: Tensile performance and stress relaxation behavior

The airship envelope composites (AEC) play a crucial role in determining the airship’s payload capacity, operation stability and service life. This paper focuses on investigating the effects of temperature and strain rate on the mechanical properties of AEC, and a visco-hyperelastic constitutive model was developed based on the Maxwell and Mooney-Rivlin models. A finite element analysis (FEA) model of the AEC was established in ABAQUS using a multiscale analysis method. The results show that the FEA simulations are in good agreement with the curves of tensile and stress relaxation experiments. The fracture strain of AEC exhibits a trend of initially increasing and then decreasing with increasing strain rate, and this effect weakens at relatively elevated temperatures. The strength of AEC decreases with increasing temperature, and this decrease becomes more pronounced at higher strain rates. Both the stress relaxation and rapid stress decay rates of the AEC are positively correlated with strain rate, but negatively correlated with temperature. The results of this study can provide valuable theoretical and methodological references for the design of envelope materials and the engineering of their application to non-rigid aircraft.