The interaction of corrosion and fatigue cracking is a complex phenomenon. While design codes provide methods of assessing certain types of defects, frequently a more accurate approach is required to predict the crack growth rate and assess the impact of corrosion damage on the critical crack size.
A series of BEASY models were developed where the surface topology was based on observed corrosion damage. The model was used to develop a relationship between the corroded surface topography and the fatigue crack growth rate. It was observed that the component life diminishes rapidly if cracks initiate in the degraded surface. The model provided quantitative data for the assessment of corroded surfaces as well as providing a tool for the assessment of specific cases observed in the field.
Improved simulation technologies coupled with experimental testing and observations from the field will result in improved inspection and maintenance programmes, better prediction of service life, and ultimately more economical maintenance management.