Numerical analysis and FBG experimental verification of transient heat and thermal-mechanical response of electrically conductive composite.

This paper presents experimental and numerical investigations into transient heat and thermal–mechanical responses of electrically conductive composite under the operating environment of solar-powered aircraft in range of ±120 °C. Four kinds of the flexible electrically conductive composites were manufactured and tested under quasi-static tensile and temperature environmental conditions, respectively. The Fiber Bragg Grating (FBG) technology was used to monitor the in-situ principal strain in composite materials at thermal steady-state condition. Based on its realistic geometry and periodic arrays, a representative volume elements (RVE) of the composite was constructed to investigate the thermal effect on the adhesive layer. The results show that the temperature effect mainly affects the interface of materials with different thermal expansion coefficients, and the more serious risk occurs at the initial process of transition from the moment of expansion to contraction. In addition, the plastic deformation range is one order of magnitude larger than the elastic deformation range and two orders of magnitude larger than the temperature deformation range in the case of 124° rotating thermal coupling analysis. It suggests that the results could provide a reliable reference for the design and lifetime evaluation of the flexible electrically conductive composites. [ABSTRACT FROM AUTHOR]