SURFACE TREATMENT METHOD OF STRUCTURAL MEMBER

摘要

PROBLEM TO BE SOLVED: To provide a surface treatment method of a structural member capable of suppressing corrosion by forming a thick coat on the surface of the structural member.SOLUTION: A surface treatment method of a structural member includes the first step for forming the first coat 11 on the surface of the structural member 10 by oxidizing the surface of the structural member, and the second step for forming the second coat 12 on the first coat 11 of the structural member by supplying aqueous solution containing metal ion after the first step. Preferably, the metal ion is trivalent ion and the ion radius is 40 pm or more and 110 pm or less.