Internal oxidation in heat-resisting stainless steels caused by presence of halides
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When Ni-20 Cr alloys or stainless steels are heated in air in contact with liquid sodium halides, massive internal oxidation can occur, but only when the surface of the alloy is not well shielded from the air by the salt film. Thus, internal oxidation can occur during intermittent exposure to an aqueous salt solution, and to high temperature oxidation. On the contrary, if the alloy is completely submerged in molten NaCl-KCl and oxidized by bubbling oxygen into the fused salt, the effective oxygen concentration at the alloy surface is too low to allow internal oxidation; only surface porosity results, as previously shown. Different morphologies of internal oxidation were observed for oxidation in the presence of NaBr, NaI, NaCl, and NaF.
KeywordsPorosity Stainless Steel Oxygen Concentration Halide Alloy Surface
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- 1.A. U. Seybolt,Oxidation of Metals 2(2), 119 (1970).Google Scholar