Corrosion of steels with surface treatment and Al-alloying by GESA exposed in lead–bismuth

Corrosion tests were performed for T91, E911 and ODS (oxide dispersion strengthened) with surface treatment and Al-alloying by pulsed electron beam (GESA—GepulsteElektronenStrahlAnlage) in flowing lead bismuth eutectic (LBE) with an oxygen content of 10−6 wt% at 550 °C for 2000 h. The result was that the surface treatment by GESA led to a faster growing multiphase oxide layer which was very homogenous in thickness. After exposure of specimens to LBE, the average oxide layer at the surface was 14–15 μm thick for ODS, 19–20 μm for E911 and 8–22 μm for T91. No dissolution attack occurred. On the surface of the Al-alloyed specimens, thin protective alumina layers were observed at the places where FeAl was formed by the GESA process, otherwise multiphase oxide layers or corrosion attack were observed.