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Reduction of service costs, reduction of local emissions and CO2-targets lead to a strong focus on electro-mobility in the automotive sector. One essential element in the electrified power train is the electrical machine that transforms electrical energy into mechanical energy and the other way round. For the PT2-topology an axial-flux-machine is very suitable because of its high power density and its flat construction. A central element is the flat rotor disc that carries the magnets and can be built from fibre reinforced polymers. For a lifespan of 8000 h the rotor disc is exposed to high mechanical and thermal loads. The knowledge of the damage development in fibre reinforced polymers under these loads is essential for a reliable design of the rotor disc and therefore the axial-flux-machine. This work presents a generic solution approach to calculate via finite element method the damage condition in FRP at any point of the thermal and mechanical load history. In the first step the loads on the rotor disc are investigated. Then corresponding static tests are derived and applied on a quasi-unidirectional woven GFRP. From these tests a damage model with linear softening is developed for FRP under static load. It is validated to tests on the rotor disc. The model is based on the classical laminate theory with a plane stress condition. Furthermore ageing tests are conducted to investigate the influence of ageing temperature and ageing time on the strength. Thermal degradation is found to be the most dominating damage mechanism. From these tests a damage model for FRP under ageing load could be derived. Finally a new progressive fatigue damage model for FRP under static, thermal and cyclic load is developed. The implementation is done in FORTRAN 12.1 and ANSYS v.15. For identification of the parameters, static tests on 0°-specimen, 90°-specimen, ±45°-specimen and ±10°-specimen at different temperatures and fibre volume fractions are necessary. Furthermore ageing tests at three different temperature levels and the evaluation of residual mass are needed. Ageing tests with a determination of the residual strength need to be performed at one high temperature level only. At last fatigue experiments at room temperature need to be performed on 0°-specimen and 90°-specimen. These tests have to be evaluated concerning the fatigue life and the residual stiffness., ISBN:978-3-906327-76-1