Prediction of Crack Growth in High Temperature Components Using Creep Crack Growth and Fatigue Crack Growth Data

Components of energy units in service are subjected to cyclic loading combined with dwell times and high temperatures. Crack growth which occurs at defects in such components is thought to be a combination of fatigue crack growth and creep crack growth. For IN 800 H at 830°C fatigue crack growth da/dN as well as creep crack growth da/dt can be described by a power law C • (A)n using J-integral for da/dN und C*-integral for da/dt as the governing parameter A. An attempt was made to predict crack growth of IN 800 H under cyclic loading including a dwell time by a combination of fatigue crack growth da/dN and creep crack growth da/dt.