US 12,286,721 B2
Method for chromium upgrading of ferritic steel interconnects for solid oxide cell stack applications
Tobias Holt Nørby, Glostrup (DK); Rainer Küngas, Harjumaa (EE); Bengt Peter Gustav Blennow, Humlebæk (DK); Jeppe Rass-Hansen, Copenhagen (DK); and Thomas Heiredal-Clausen, Birkerød (DK)
Assigned to HALDOR TOPSØE A/S, Kgs. Lyngby (DK)
Appl. No. 17/616,756
Filed by HALDOR TOPSØE A/S, Kgs. Lyngby (DK)
PCT Filed Jul. 13, 2020, PCT No. PCT/EP2020/069710
§ 371(c)(1), (2) Date Dec. 6, 2021,
PCT Pub. No. WO2021/009100, PCT Pub. Date Jan. 21, 2021.
Claims priority of application No. PA 2019 00882 (DK), filed on Jul. 17, 2019.
Prior Publication US 2022/0298663 A1, Sep. 22, 2022
Int. Cl. C25D 3/04 (2006.01); C25D 5/36 (2006.01); C25D 5/50 (2006.01); C25D 7/06 (2006.01); H01M 8/0228 (2016.01)
CPC C25D 3/04 (2013.01) [C25D 5/36 (2013.01); C25D 5/50 (2013.01); C25D 7/0692 (2013.01); H01M 8/0228 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for chromium upgrading of interconnects made of ferritic steel to be used in solid oxide cell stacks, comprising the steps of:
shaping the interconnect,
depositing a coating comprising Cr on at least one surface of the shaped interconnect,
performing one or more thermal treatments at a temperature below 1000° C.,
whereby the resulting Cr concentration near the surface of the interconnect is higher than the Cr concentration in the ferritic steel before shaping.