Jivkov's articles
Strain-driven corrosion crack growth
A pilot study of intergranular stress corrosion cracking
Abstract
This work proposes a model for corrosion driven crack growth.
The model poses a moving boundary problem, where a chemical attack removes material
from the body. The rate of the chemical attack is a function of the strain along the
body surface. No crack growth criterion is needed for the analysis. A finite strain
formulation is used and the material model is assumed hyperelastic. The problem is
stated for a large body, containing a large crack. A low frequency cyclic loading is
considered. Thus, corrosion is assumed to dissolve material with a rate, approximately
proportional to the strain rate. The problem is solved using finite element method
based program, enhanced with a procedure handling the moving boundary. Parametric
studies are performed for a series of different initial shapes of the near-tip region.
Presented results show that the crack growth rate is largely dependent on the initial
crack geometry. For a set of initial shapes and load levels steady-state conditions of
growth are achieved, while for the others the cracks show tendency to branch.