Jb. Vogt et al., Fatigue damage evaluation of a power plant component from analysis of the dislocation structures, ENG FAIL AN, 7(5), 2000, pp. 301-310
The paper presents a method for estimating the degree of fatigue damage in
an engineering ferritic-bainitic steel. A dislocation microstructure chart
is first established from laboratory fatigue tests. Misorientation measurem
ents are carried out after fatigue failure between dislocation cells produc
ed by cyclic loading in ferrite grains and between dislocation cells in bai
nite originated by the heat treatment. There is shown to be a clear depende
nce of these values on the strain amplitude. On this basis, the analysis of
the microstructure of a steel taken from a component which failed in servi
ce allowed the determination of the strain amplitude value to which the com
ponent had been subjected. (C) 2000 Elsevier Science Ltd. All rights reserv
ed.