Al-containing ODS steels with improved corrosion resistance to liquid lead–bismuth

The effectiveness of Al addition for improvement of the corrosion resistance of ODS steel in lead–bismuth eutectic (LBE) was investigated. Al-alloying surface treatment using a GESA facility was applied to 9Cr-ODS martensitic steel, and the corrosion resistance in stagnant LBE containing 10−6 wt% oxygen was subsequently examined. Corrosion resistance of ODS ferritic steels with high Cr content (14.7 wt%), containing 3.3–3.8 wt% Al and small amounts of Zr or Hf, was also examined. Al-alloying surface treated 9Cr-ODS martensitic steel was tested at 650 °C and ODS ferritic steels with high Cr content, containing 3.3–3.8 wt% Al and small amounts of Zr or Hf, were tested at 650 and 700 °C. The maximum exposure duration was 10,000 h. All tested materials showed good corrosion resistance under all test conditions. Both the Al-alloying surface treatment by the GESA facility and the Al addition to the matrix with small amounts of Zr or Hf effectively improved the compatibility of ODS steel with LBE at high temperatures.