A new method for the measurement of static and dynamic Young’s moduli of long fibres

This article describes a new laser systems to measure the Young’s modulus of a long fibre based on the diffraction of light. Two setups are presented. The first setup has been used to measure the static Young’s modulus of a thin basalt fibre (10 μm diameter, 93 mm length). The second setup called “impulse mechanical spectrometer” was used to measure the dynamic Young’s modulus of a long polyamide fibre (128 μm diameter, 371 mm length). A change of the vibration frequency is achieved by changing the length of the fibre or the load. The damping coefficient was also estimated in the dynamic characterisation. The presented experimental method does not require calibration.