Abstract:Applying an electrically insulating coating on the inner surface of the lithium flowing ducts is a feasible way to effectively mitigate the MHD pressure drop for Li/V self-cooled blanket. This paper mainly overviews the present progress and issues of the insulating coatings, including the single-layer insulator and the multilayer insulatos. Many studies have showed that the single-layer insulator does not perform as stablely as theoretically especially at elevated temperatures, so the necessary of development of the multilayer insulators has been stressed. However, the currently investigated “V-alloy/insulator/metal” structured multilayer insulting coating (such as V-alloy/Er2O3/V) exists some obvious weaknesses, such as the difficulty in realizing the in situ formation and self-healing of the surface metal layer, the compatability problem between lithium and the surface metal layer. Then a new V-alloy/metal/insulator structured multilayer insulator is proposed, which has the potential to realize the in situ formation and self-healing and probably a new possibility for the development of the insulating coating.