Austenitic stainless steel is well-established in nuclear industry due to excellent mechanical behavior and corrosion resistance. One of specific deformation modes common to this type of steels when exposed to harsh irradiated environment is strain localization in terms of slip and kink bands (clear channels), which can play an important role in the initiation of intergranular cracking. In this study, the formation of clear channels is analyzed in numerical simulations of neutron-irradiated austenitic stainless steel using the Fast Fourier Transform (FFT) solver employed in the framework of finite strain classical crystal plasticity. The traditional basic scheme is equipped with different modified Green operators (F. Willot, 2015) and Anderson acceleration technique to obtain a converged solution of the deformation gradient field for the applied tensile aggregate loading. A special attention is given to crystal-lattice rotation evolution to distinguish different aspects of clear channels (A. Marano 2020). References: [1] Willot, F., Fourier-based schemes for computing the mechanical response of composites with accurate local fields, Comptes Rendus Mécanique, Vol. 343 (3), pp. 232-245, 2015. [2] Marano, A., Numerical simulation of strain localization in irradiated polycrystals, No. FRCEA-TH--12154), MINES ParisTech.