Champion Pits: Competitive Interactions During Chloride Pitting Of Stainless Steels

To make quantitative predictions of the evolution of pitting corrosion damage over time, it is necessary to understand not only the critical factors controlling the stability of a single pit, but also the electrochemical interactions between simultaneously propagating pits. In this paper, we compare the development of pit populations over time in potentiostatic and galvanostatic experimental conditions. To do this, we have implemented a multiple-pit version of a previously developed algorithm for simulating the propagation of single pits in stainless steel. Propagation of each pit is assigned to a separate process and these processes can be distributed over several computers, thereby allowing multiple (coupled) pit simulations to be run in the same time as a single pit simulation. Results from many-pit simulations using this method will be presented, with a focus on the development of the largest (or ‘champion’) pits.