During service at elevated temperatures extensive formation of particles can take place that can have adramatic influence on mechanical properties. Precipitation of ?-phase and M23C6-carbides have been studiedboth experimentally and with thermodynamic modelling for 25Cr20Ni austenitic stainless steels (AISI 310) at800 ºC for up to 5000 h. Previous work has demonstrated that the modelling could describe the nucleation andgrowth satisfactory. After long term ageing the particles form bands in the microstructure. In the present paperthe influence of these bands on ductility and toughness at room temperature is analysed. For this purposepreviously developed models for ductility and toughness are utilised. Model values for banded and non-bandedmicrostructures have been generated for casts of 310 in fine and coarse grained conditions with 0.04 and0.12%N. The model values show that in the coarse grained condition, no reduction in ductility and toughnesscan be expected in the banded microstructure. In the fine grained condition a modest reduction is predicted
