Sammendrag
ABAQUS FE simulations of hydrogen diffusion in duplex stainless steel have been performed.
Three models with different ferriteeaustenite configurations have been applied
and the hydrogen diffusion and the hydrogen coefficient have been evaluated as a function
of austenite phase size and shape and the calculated diffusion coefficients compared to
literature. Hydrogen concentration due to stress and plastic strain close to an embedded
flaw has also been evaluated. An important observation is that the simulations show that
when the austenite phases are saturated with hydrogen there is no large difference in the
overall diffusion rate between the small and large phased models, i.e. no influence of
tortuosity is observed. The work clearly demonstrates that both microstructure and flaws
will influence the hydrogen diffusion and the hydrogen concentration and hence, must be
taken into account when evaluating the susceptibility of hydrogen stress cracking in
duplex stainless steels.
Three models with different ferriteeaustenite configurations have been applied
and the hydrogen diffusion and the hydrogen coefficient have been evaluated as a function
of austenite phase size and shape and the calculated diffusion coefficients compared to
literature. Hydrogen concentration due to stress and plastic strain close to an embedded
flaw has also been evaluated. An important observation is that the simulations show that
when the austenite phases are saturated with hydrogen there is no large difference in the
overall diffusion rate between the small and large phased models, i.e. no influence of
tortuosity is observed. The work clearly demonstrates that both microstructure and flaws
will influence the hydrogen diffusion and the hydrogen concentration and hence, must be
taken into account when evaluating the susceptibility of hydrogen stress cracking in
duplex stainless steels.