To provide a high strength multilayer steel sheet and a high strength hot dip galvanized multilayer steel sheet good in plating wettability and press workability and to provide its production method by continuous casting.
In this high strength multilayer steel sheet good in plating wettability and press workability, steel in which the internal layer part has a composition containing, by mass, 0.05 to 0.15% C, 0.3 to 2.0% Si, 1.5 to 2.8% Mn and 0.005 to 0.5% Al, and the balance Fe with inevitable impurities, and in which, provided that %C, %Si and %Mn respectively denote C, Si and Mn contents, (%Mn)/(%C)≥15 and (%Si)/(%C)≥4 are satisfied, is used as a base metal, and the surface layer part of the base metal is composed of a layer having a composition containing 0.05 to 0.15% C, 0.3 to 2.0% Si, 1.5 to 2.8% Mn, 0.005 to 0.5% Al and 0.01 to 5.0% Ni, and the balance Fe with inevitable impurities.
SHIODA KOSAKU
SAKUMA KOJI
TAKADA YOSHIHISA
TAKAHASHI AKIRA
