Modeling of Creep Deformation Behaviour of RAFM Steel

Creep tests were carried out on reduced activation ferritic-martensitic steel at 773, 823 and 873 K. Creep strain-time trajectory obtained was subsequently modeled by 4-theta projection methodology. An optimum cutoff strain was defined in tertiary regime for better representation of creep curves. The theta values were correlated with applied stresses and temperatures by artificial neural network for robust prediction. Following this, the design related creep properties such as time to reach 1 % strain, time to rupture and minimum creep rate were predicted successfully.