Enhanced crevice corrosion of stainless steel 316 by degradation of Cr-containing hollandite crevice former

Abstract

This study explores the corrosion interactions between stainless steel 316 (SS316), a candidate nuclear waste canister material, and Cr-containing hollandite (Ba1.15Cr2.3Ti5.7O16), a model ceramic nuclear waste form. The two materials were corroded in close proximity in 0.6 M NaCl solution at 90 °C for 28 days. Severe crevice corrosion was observed on the stainless steel surface after the corrosion experiment, which is likely associated with the rapid accumulation of Cr3+ cations originating from both SS316 and the Cr-containing hollandite. The enhanced corrosion of SS316 by the corrosion products of hollandite is quantitatively explained using a classical crevice corrosion model.