Aluminized steel sheets are promising materials for use as maintenance-free roofing or siding because of their superior corrosion resistance in comparison to galvanized steel sheets in a corrosive atmospheric environment. In this paper, the corrosion behavior of aluminized steel sheets has been investigated using test panels exposed for over 30 years. Corrosion of aluminized steel sheets was slight and their surfaces were covered with corrosion products mainly containing Fe.

Reduction of Pb has become an urgent topic in discussions of ways to reduce the burden on the environment. The authors have been developing substitutive materials made of Pb-8 wt% Sn coated steel sheets (which are known as Terne sheets) for automotive fuel tanks and chassis for home electrical appliances.Results have confirmed that Sn-Zn hot-dip coated steel sheets produced by a flux method can substitute for Terne sheets.The Sn-Zn hot-dip coated layer has a lower potential than Fe due to the content of a small amount of Zn. The layer also displays sacrificial corrosion protection.Zn crystal in the coated layer becomes coarse and Zn dissolves excessively when the Sn-Zn coated layer is over 11 wt % Zn.Accordingly, Sn-8 wt% Zn is the most balanced composition for sheets used for inner and outer corrosion resistance in fuel tanks.Results confirmed that Sn-Zn hot-dip coated steel sheets treated with special chemically treated film can confirm to various characteristics for fuel tanks. Subsequent use of lead for automotive parts may be reduced sharply.

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