Corrosion properties of UNS S32750, UNS N06022 and UNS N10276 in seawater

High alloyed Ni-alloys are used to replace 25% Cr super duplex stainless steels in seawater.  Seawater is a complex electrolyte often treated with chlorine to kill biological species.  The corrosion resistance of both stainless steels and Ni-alloys depends on the electrochemical surface potential and the temperature.  This paper describe results from testing of specimens with artificial crevices in 3.5% NaCl polarized in the range +200 to -800 mV SCE to simulate actual potential range in seawater.   Critical crevice temperature for substrate material and welded specimens will be presented.