Microstructure of intermetallic particle strengthened high-chromium fully ferritic steels

An improvement of power plant efficiency necessitates an increase of the process parameters and thus enables a reduction of consumed primary resources. Furthermore more efficient, sustainable, flexible and cost-effective energy technologies are strongly needed. For this reason the current research concentrates on a new concept of high-chromium fully ferritic stainless steels which are strengthened by a combination of solid-solution and intermetallic Laves phase particles. Such steels exhibit favourable creep, thermomechanical fatigue and steam oxidation behaviour up to 650°C. Based on detailed analysis by high-resolution scanning and transmission electron microscopy the particle size evolution and compositions were studied. Variations in chemical compositions were analysed experimentally and compared with thermodynamic equilibrium composition modelling results