Mechanical properties and non-destructive evaluation of chromium-molybdenum ferritic steels for steam generator application

Abstract

The paper presents high temperature mechanical properties and non-destructive evaluation (NDE) of chromium-molybdenum (Cr-Mo) ferritic steels widely used as structural materials for steam generator (SG) applications. Creep and low cycle fatigue deformation and damage (the important design considerations for SGs) of ferritic steels are presented. Recent trend and advances in ferritic steels for SG applications are discussed. The paper also highlights the recent results obtained on creep and fatigue properties of indigenously developed steels. Weld and weld joints of ferritic steels are known to be the weak links affecting the life of the components. The creep properties of weld joints are presented. Apart from mechanical behaviour of ferritic steels, the paper deals with some of the recent results on the characterisation of microstructural features such as grain size, nucleation and growth of secondary phases, degradation of microstructure due to thermal ageing and creep, and assessment of creep and fatigue damage of ferritic steels using advanced NDE techniques.