The importance of steel chemistry and thermal history on the sensitization behavior in austenitic stainless steels: Experimental and modeling assessment

Sensitization of Austenitic Stainless Steels: Current Developments, Trends, and Future Directions

“…The mitigation approach to control sensitization has been investigated by researchers since 1920. These include traditional approach (alloy chemistry [46,47], carbide formers, solution annealing, solute atoms) to emerging techniques. These are detailed below.…”

The Effect of Sensitization on the Susceptibility of AISI 316L Biomaterial to Pitting Corrosion

“…Due to this phenomenon, the austenitic grains become locally chromium-depleted. If the proportion of chromium is reduced below the passivation limit, sensitization with consequent susceptibility to the intergranular corrosion in aggressive environments occurs [ 12 , 13 , 14 , 15 , 16 , 17 ]. The mentioned process, resulted from the exposure to the so-called critical temperatures (500 °C to 800 °C) with slow cooling may most often come into consideration at an inappropriately chosen processing temperature.…”

“…The mentioned process, resulted from the exposure to the so-called critical temperatures (500 °C to 800 °C) with slow cooling may most often come into consideration at an inappropriately chosen processing temperature. The minimum time for sensitization depends on several factors including the specific alloy composition, temperature, carbon content, heating rate and presence of other alloying elements [ 12 , 13 ]. It is important to note that sensitization is a gradual process that occurs over time.…”

Application of double loop electrochemical potentio-kinetic reactivation for characterizing the intergranular corrosion susceptibility of stainless steels and Ni-based alloys in solar nitrate salts used in CSP systems

“…The diffusion coefficient of carbon is 10 4 larger than that of chromium due to the fact that carbon is present interstitially and chromium substitutionally [11]. S. Kolli [12] deduced that the preferential precipitation along the GBs is controlled by two factors, thermodynamics of the M23C6 formation and the difference in the diffusivities of Cr and C. After the formation of M23C6 at the grain boundaries, they become a kind of crystal defects with a higher Gibbs energy [10]. To reduce the Gibbs energy of the system, GBs tended to interact with other lattice defects (dislocations, vacancies and foreign atoms) [13] and thus lower the corrosion resistance of the material.…”

“…Chromium-depletion theory suggest that annealing at critical temperature or cooling slowly leads to the precipitation of carbides along the GBs [11], thus resulting in the local Cr content dropping below a critical level of 12 wt.% [15,17]. In the region adjacent to GBs after precipitation, a minimum chromium content is unavailable to provide the passive Cr2O3 layer for corrosion resistance [12]. The working temperature range for molten salt is partly overlaid with the sensitisation temperature.…”