The metastable pitting behavior for two grades of austenitic stainless steel, AISI 304L and 316L have been investigated for a range of controlled hydrodynamic conditions: static, laminar and turbulent (Reynolds numbers of 1000, 2000, 3000, 10000, 50000 and 75000). Metastable pitting was evident under all flow regimes. Fluid flow, whether laminar or turbulent, appeared to have little overall effect on the nucleation rates of metastable pitting events. Conversely, stable pit growth was most evident at Reynolds numbers immediately before the transition to turbulent flow and close to the critical velocity @1.5 ms -~) at Reynolds numbers of approximately 2000 and 50000 respectively. The corrosion behavior of the two austenitic stainless steels has been compared with UNS $32760 exposed to the same hydrodynamic conditions.
Keywords: stainless steel, pipe flow, corrosion, critical velocity, dimensionless groups, electrochemical noise, electrolyte flow, friction factor, hydrodynamic, pitting