Effect of hydrogen on pitting susceptibility of 2507 duplex stainless steel

The hydrogen-induced pitting corrosion mechanism in duplex stainless steel studied by current-sensing atomic force microscopy

“…It is generally accepted that pitting is a result of the localized breakdown of the passive film, which usually occurs at specific sites of low film stability. 23 In our previous research, 24 pitting of a hydrogen-charged specimen exposed to a 6% FeCl 3 solution initially occurred at the grain boundaries or at the austenite grains, and then appeared at the ferrite grains. Therefore, areas with poorly insulating passive film, such as grain boundaries and austenite grains, can be considered more susceptible to pitting corrosion.…”

“…Thus, it can also be deduced that pitting corrosion will preferentially begin at the grain boundaries or in the austenite phase of 2507 duplex stainless steel, which matches our previous results. 21,24,25 CSAFM was used to directly observe the conductivity of passive film formed on grain boundaries, austenite and ferrite grains prior to hydrogen charging. The passive film on austenite grains and grain boundaries had much higher conductivity than on ferrite grains.…”

Suitability of UNS S31603 steel for geothermal brines in volcanic areas – Influence of different physicochemical conditions on its corrosion behavior

“…An increase in its rate, due to the hydrogen ion abundance, results in an increased anodic (metal dissolution) reaction rate (Revie, 2000). Furthermore, hydrogen may incorporate in the passive film formed on the metal surface (Thomas, 1961), thereby forming positively charged localized sites and promoting the adsorption of negative chloride ions on the metal surface (Guo et al, 2013). Two, in terms of corrosion, unexplored geothermal sites were chosen for this study -Sibayak (North Sumatra) and Lahendong (North Sulawesi), geothermal "hotspots" of Indonesia, the country with the greatest geothermal potential in the world.…”

Corrosion behavior of hydrogen charged super duplex stainless steel welded joints

“…The morphology of the austenite grains is also relevant – more dispersed grains will favor extension of the ways of hydrogen diffusion and increase of the amount of trapped hydrogen more intensely than in case of wider grains, separated by broad bands of ferrite . Moreover, the corrosion susceptibility of DSS may increase with hydrogen charging current density . Accordingly, the understanding and control of passivation in hydrogen‐charged material has been a key factor for better protection of DSS‐welded joints against corrosion damage.…”