Nippon Steel Corporation

Yusho Oyama

Jun Maki

Yasuto Goto

Masao Kurosaki

Seiji Sugiyama

Teruaki Izaki

Haruhiko Eguchi

Nobuyoshi Okada

Takayuki Ohmori

Yu Ando

Masaaki Yamamoto

Masaaki Enjuji

Tomohide Kamiyama

A Sn-based metal-coated steel strip excellent in appearance comprises a Ni-based metal (such as Ni, a Ni&#x2014;Sn alloy, a Ni&#x2014;Zn alloy, a Ni&#x2014;Fe alloy and a Ni&#x2014;Co alloy) preplating layer and a Sn-based metal (such as a Sn&#x2014;Zn alloy) coating formed thereon, and is characterized in that a Ni emission intensity line and an Fe emission intensity line obtained by glow discharge spectroscopy of the surface of the coated steel strip satisfy a relationship of the formula: T&#x2267;Twherein Tis a sputtering time at the peak of a Ni emission intensity line, and Tis a sputtering time at the inflection point of an Fe emission intensity line, or a relationship of the formulas: T&#x2267;T, and 1&#x2266;T/T&#x2266;1.5

Sn-based metal-coated steel strip excellent in appearance and process for producing same

A hot-dipped aluminum coated steel sheet including, on the surface thereof, a coating layer consisting of 2 to 15 wt % of Si, not greater than 1.2 wt % of Fe, 0.005 to 0.6 wt % of Mn, 0.002 to 0.05 wt % of Cr and the balance of Al and unavoidable impurities, and an alloy layer disposed between the coating layer and the steel sheet, having a thickness of not greater than 7 .mu.m and having a mean composition consisting of 20 to 50 wt % of Fe, 3 to 20 wt % of Si, 0.1 to 10 wt % of Mn, 0.05 to 1.0 wt % of Cr and the balance substantially consisting of Al. This steel sheet can be produced by conducting coating in a coating bath consisting of 3 to 15 wt % of Si, 0.5 to 3.5 wt % of Fe, 0.05 to 1.5 wt % of Mn, 0.01 to 0.2 wt % of Cr and the balance substantially consisting of Al, or by adjusting the sum of the concentrations of Zn and Sn in the impurities in the coating layer to not greater than 1 wt %.

Hot-dipped aluminum coated steel sheet having excellent corrosion

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Kitakyushu, Japan

Yusho Oyama