Mechanistic Understanding of the Dissolution Behavior of the Precipitates in 12Cr Martensitic Steel during Potentiodynamic Polarization in Strong Alkaline Solutions

Cr was reported to result in a selective dissolution of the Laves phase in 12Cr steel in strong alkaline solutions. However, the current study concludes that Cr does not cause the dissolution of the Laves phase, but plausibly is responsible for the dissolution of Cr carbide at a higher potential. Further, the shoulder of the Laves phase peak resulted from the change of magnetite to hematite on the surface, and the shoulder of the carbide peak resulted from the transpassive behavior of Cr as alloying elements in the matrix.