Dynamic characterisation and modelling of the orthotropic self-reinforced polypropylene used in alternative FMLs

In this work, the dynamic characterisation and the modelling of the orthotropic self-reinforced polypropylene used in alternative Fibre Metal Laminates (FMLs) was carried out. All the complex moduli were characterised by means of the DMA test in a frequency range of 0-60 Hz. In addition to the DMA test, the Young's modulus was characterised by a forced vibration with resonance test, 0-2500 Hz, where a good correlation between the two tests were observed. In the case of the complex shear modulus, it was determined based on the complex Young's modulus and Poisson's ratio characterisation of [45/−45] laminate. Both the complex Young's modulus of [0/90] and [45/−45] have been modelled. The results predicted by the model of [0/90] have been correlated with the experimental results obtained at different orientations. The greatest influence of frequency in both Young's modulus and loss factor were found at [0/90]. Additionally, according to the correlation, the greatest deviation was found at 10° and in general at high frequencies the deviation was better than at low frequencies.