Corrosion tests on austenitic samples with alumina and alumina-forming coatings in oxygen-containing stagnant Pb and turbulently flowing PbBi
A. Heinzel, Renate Fetzer, Fabian Lang, A. Weisenburger, Sebastiano Cataldo, Fabio Di Fonzo, Georg Müller
Abstract
Two differently produced alumina coatings (by pulsed laser deposition (PLD) and detonation gun (DG)) and one alumina-forming coating realised by pack cementation are proposed as a protection barrier against corrosion of austenitic steels in Pb and PbBi. Samples were tested in oxygen-controlled stagnant Pb (10−7 wt.%) at 480°C and 550°C for up to 10000 h and in turbulently flowing (up to 1.6 m/s) PbBi eutectic at 490°C with 10−9 – 10−8 wt.% oxygen for about 500 h. All exposed coatings showed a good behaviour in flowing PbBi and in stagnant Pb at around 480°C independent of the oxygen content. At 550°C, the PLD coating failed most probably due to incomplete coating of the sample, while the DG sample protected the base material.