Intergranular corrosion in evolving media: experiment and modeling by cellular automata

TL;DR

This study examines how different nitric acid oxidation conditions affect intergranular corrosion in stainless steel, using experiments and cellular automata modeling to understand surface evolution and corrosion dynamics.

Contribution

It introduces a combined experimental and cellular automata modeling approach to analyze intergranular corrosion under varying oxidizing conditions.

Findings

Severe conditions lead to thicker oxide layers and larger surface areas.

Corrosion surface reaches different steady states depending on oxidizing conditions.

System re-adapts to softer conditions without memory of previous severe corrosion.

Abstract

We investigate the impact of the oxidizing character of the nitric medium on the evolution of the intergranular corrosion of a stainless steel. In two different oxidizing conditions ("severe" and "soft"), the corroded surface of the steel reaches a different steady state: the oxide is thicker, the intergranular grooves are thinner and the surface area is larger in the "severe" conditions than in the "soft" ones. Then we investigate the effect of an alternative "severe then soft" corrosion sequence. We show that the system re-adapts to the "soft" conditions without memory effect from the previous "severe" ones. bstra