Nuclear chemistry

Metallurgy

Materials science

Physical chemistry

Chloride

Alloy

Environmental chemistry

Washer

Analytical Chemistry (journal)

Corrosion

Chemistry

Crevice corrosion

Procedia Materials Science

The crevice corrosion repassivation potential was determined by the Potentiodynamic–Galvanostatic-Potentiodynamic (PD–GS–PD) method. Alloys 625, C–22, C–22HS and HYBRID–BC1 were used. Specimens contained 24 artificially creviced spots formed by a ceramic washer (crevice former) wrapped with a PTFE tape. Crevice corrosion tests were performed in 0.1 mol/L and 1 mol/L NaCl solutions at temperatures between 20 and 90 °C, and CaCl2 5 mol/L solution at temperatures between 20 and 117 °C. The crevice corrosion resistance of the alloys increased in the following order: 625 < C–22 < C–22HS < HYBRID–BC1. The repassivation potential (ECO) showed the following relationship with temperature (T) and chloride concentration ([Cl−]) ECO = (a + b T) log [Cl−] + c T + d; where a, b, c and d are constants. At temperatures above 90 °C, ECO for alloy 625 stabilized at a minimum value of –0.26 VSCE.

Effect of Environmental Variables on Crevice Corrosion Susceptibility of Ni–Cr–Mo Alloys for Nuclear Repositories