Thermomechanical viscoelastic analysis of woven-reinforced thermoplastic-matrix composites

The behaviour of four different woven-reinforced thermoplastic-matrix laminates was analysed using dynamic mechanical thermal analysis. The investigation was focussed on a temperature range relevant for applications in the automotive industry, namely between −30 °C and 80 °C. Storage modulus master curves were built for each material in three different orientations. Dependence of the tensile and shear moduli on frequency was described using Prony series. This description was then introduced in a phenomenological transversely isotropic viscoelastic material model. Shift factors determined in the frequency domain were converted to time domain and used in the proposed constitutive model. The model was implemented in Abaqus/Standard using a user material subroutine (UMAT) and validated by comparing relaxation and creep predictions with experimental data.