Creep Modeling for Life Evaluation of Heat-resistant Steel with a Martensitic Structure

Abstract

A tertiary creep model, the Ω method, previously proposed for creep life prediction was modified so as to be applicable to martensitic steels with a pronounced primary creep region. Primary creep behavior was described by a logarithmic creep equation with two parameters dependent on stress and temperature. Correlations between newly introduced primary creep parameters and tertiary ones were studied. The proposed creep model, which takes into account for primary and tertiary creeps, described the creep curves satisfactorily and predicted creep life accurately.