An anisotropic creep model for continuously and discontinuously fiber reinforced materials

he present study is concerned with the formulation, implementation and validation of anisotropic creep laws for neat thermoplastic matrix materials, discontinuously long fiber reinforced thermoplastic (LFT) composite materials with process dependent fiber preference directions as well as unidirectionally fiber reinforced thermoplastic tapes. Based on a simple three term Kelvin-Voigt approach, an anisotropic model is formulated and implemented into a finite element program. The model is validated against an experimental data base of creep experiments on continuously and discontinuously fiber reinforced materials.