Frequency domain analysis of mechanical properties and failure modes of PVDF at high strain rate

摘要

Fast Fourier transform (FFT) theory is used to analyze the tensile stress-strain curves of coated fabric membrane materials (PVDF) at high strain rates (350/s, 500/s, 750/s, 900/s and 950/s). The transformation results are extended to characterize the failure and dynamic response of Ferrari 1002S2 in frequency domain. Firstly, the dynamic mechanical properties of the materials are analyzed, which include stress-strain relationship curve, ultimate tensile strength, fracture elongation and fracture energy density. Then, the stress-time, strain-time and voltage-time signals are converted in frequency domain, and the dynamic mechanical properties of materials are analyzed from the point of view of frequency domain. Finally, according to the power-frequency curve obtained from the voltage-time signal, the corresponding relationship between the failure mode and the frequency domain is proposed. Besides, the typical power-frequency curve corresponding to each failure mode is analyzed by combining with the failure mode of the specimens. The results show that the dynamic mechanical properties of Ferrari 1002S2 materials are analyzed well from the point of view of frequency domain. The failure mode is directly related to the frequency domain distribution. (C) 2019 Elsevier Ltd. All rights reserved