![[ Visit Client Website ]](images/banner.gif)
Monday, March 23, 2009: 1:55 PM
C308 (Georgia World Congress Center)
Duplex stainless steel (DSS) may become susceptible to environmental assisted
cracking (EAC) in sulfide-containing caustic solutions. The effects of hydrogen on as-received
and annealed specimens of grade 2205 DSS exposed to a white liquor, comprised of 150 g/l
NaOH and 50 g/l Na2S as well as sulfide-free caustic solution of 150 g/l NaOH have been
evaluated by microhardness and nanoidentation after potentiostatic polarization in the
solutions at room temperature for different times. A hydrogen microprint technique (HMT) was
also used to evaluate the hydrogen accumulation sites on the surface. The microhardness
and nanoidentation data suggests that sulfur species promote hydrogen absorption in caustic
solutions. The ferrite phase underwent a greater increase in hardness as compared to the
austenite phase. Hydrogen absorption in 2205 DSS was possible at the cathodic potential of -
1.2 V versus standard calomel electrode (SCE) in white liquor; however, the effects of
hydrogen on the material behavior appear to be minimal based on the hardness data.
cracking (EAC) in sulfide-containing caustic solutions. The effects of hydrogen on as-received
and annealed specimens of grade 2205 DSS exposed to a white liquor, comprised of 150 g/l
NaOH and 50 g/l Na2S as well as sulfide-free caustic solution of 150 g/l NaOH have been
evaluated by microhardness and nanoidentation after potentiostatic polarization in the
solutions at room temperature for different times. A hydrogen microprint technique (HMT) was
also used to evaluate the hydrogen accumulation sites on the surface. The microhardness
and nanoidentation data suggests that sulfur species promote hydrogen absorption in caustic
solutions. The ferrite phase underwent a greater increase in hardness as compared to the
austenite phase. Hydrogen absorption in 2205 DSS was possible at the cathodic potential of -
1.2 V versus standard calomel electrode (SCE) in white liquor; however, the effects of
hydrogen on the material behavior appear to be minimal based on the hardness data.