Protection of nitrided stainless-steel components from corrosion by water

Dissolution and Passivation of a Silicon-Rich Austenitic Stainless Steel during Active-Passive Cycles in Sulfuric and Nitric Acid

“…7,15,16 A high silicon enrichment (over 1 wt%) of a 18Cr-15Ni SS proved to lower the risk associated with such passivity breakdown in the presence of oxidizing species. [18][19][20][21][22][23][24]37 The X1CrNiSi18-15-4 SS (composition given in Table I) was designed for these kinds of electrolytes, where its dissolution rate was shown to be lower than for the X2CrNiN18-10 SS. It is however not the case in pure HNO 3 , where the X1CrNiSi18-15-4 SS dissolves more rapidly than the X2CrNiN18-10 SS, and this is probably due to the properties of the particular passive layer of the X1CrNiSi18-15-4 SS.…”