GALVANNEALED STEEL SHEET EXCELLENT IN FILM ADHESION

摘要

PROBLEM TO BE SOLVED: To provide a galvannealed steel sheet superior in film adhesion compared to the conventional one by controlling the structure of aδ1-phase in a plating film. SOLUTION: This galvannealed steel sheet is obtained by forming a hot-dip galvanizing layer on the surface of a steel sheet and carrying out alloying treatment. At a surface depth of >=1/3 of the thickness of the galvanizing layer from the surface of the galvanizing layer, the (001) plane of theδ1-alloy phase is preferentially oriented so that it has an angleθof >=50 deg. with respect to the steel-sheet surface 1.