Influence of Plastic Deformation on Dissolution Corrosion of Type 316L Austenitic Stainless Steel in Static, Oxygen-Poor Liquid Lead-Bismuth Eutectic at 500°C

Early stages of dissolution corrosion in 316L and DIN 1.4970 austenitic stainless steels with and without anticorrosion coatings in static liquid lead-bismuth eutectic (LBE) at 500 °C

“…Their density clearly increases in cold worked steels, but due to their fineness it is difficult to monitor their distribution throughout the steel bulk. As the density of deformation twins is higher in cold worked steels, the susceptibility of cold worked steels to dissolution corrosion is expected to be higher, in agreement with previous studies [8,9,13,47]. TEM characterization of the deformation twins in the 316L-r-CW steel heat has been reported earlier by Lambrinou et al [8];…”

“…Despite their small size, the homogenously distributed annealing twins in this steel are expected to contribute to the local progress of LBE dissolution attack, especially for dissolution depths greater that the width (10-20 µm) of the outer zone that seems to be devoid of such twins. Another steel microstructural feature that has been clearly shown in earlier studies [8,9,13,47] to promote the progress of LBE dissolution attack in 316L stainless steels are deformation twins.…”

“…4, the 316L and DIN 1.4970 steels used in this work are characterized by different crystallographic textures. All cold-worked steels (1.4970-t-24CW, 1.4970-t-46CW, 1.4970-b-20CW, and 316L-r-CW) showed a mixed <111> and <001> texture, typical for austenitic (fcc) stainless steels [9,47], such as the 316L and DIN 1.4970 steels used in this work. A less strong texture was observed in all solution-annealed steels (1.4970-t-HT, 1.4970-b-SA, 1.4970-r-SA, and 316L-p-SA), as expected.…”

“…In fact, it has been shown that steel grains with the <111> orientation close to the direction of steel tensile loading (e.g., load resulting in cold deformation) favor LBE dissolution attack, while grains with the <001> orientation delay locally the attack [9]. The higher susceptibility of grains with the <111> orientation to LBE dissolution attack may be attributed to their high density of deformation twins, as such twins are known to promote the LBE ingress into the steel bulk [8,9,13,47]. As was pointed out in earlier studies [48],…”

Corrosion resistance and microstructural stability of austenitic Fe–Cr–Al–Ni model alloys exposed to oxygen-containing molten lead

“…%) molten Pb or Pb-Bi-eutectic (LBE) alloy. Studies, aimed at in-depth understanding of the steels-specific HLM-corrosion mechanisms, have been performed on austenitic steels at temperatures below 500°C in LBE, mainly with low and ultralow oxygen concentrations (≤ 10 -7 wt.%) in order to accelerate the dissolution corrosion phenomenon [105][106][107][108]. These studies describe in detail the relationship between the steels microstructure and HLM corrosion.…”