Cover Image, Volume 9, Issue 1

Electron probe elemental maps of Fe and Ni/Co at the interface of the BL‐MTNi3 (a) and BL‐MTCo3 (b) coated steel. Ni ²⁺ is more likely than Co ²⁺ to be reduced by Fe ²⁺ . Once a few Ni ²⁺ ions diffuse out from the NiO‐bearing MTNi3 layer and encounter Fe ²⁺ in the NiO‐ and CoO‐free BL, the reaction between them takes place and FeNi micro‐alloys precipitate. image