C22C18/04

Hot dip zinc alloy plated steel sheet having excellent corrosion resistance and external surface and method for manufacturing same

Provided is a hot dip zinc alloy plated steel sheet which is widely used in vehicles, domestic appliances, construction materials or the like and a method for manufacturing the same. A Zn—Al—Mg hot dip zinc alloy plating bath is used for manufacturing the hot dip zinc alloy plated steel strip, and a small amount of Ga or In is added to the plating bath for inhibiting an oxidation reaction of Mg in the plating bath so as to obtain excellent corrosion resistance and external surface of the plated steel sheet which is manufactured at this point.

Hot dip zinc alloy plated steel sheet having excellent corrosion resistance and external surface and method for manufacturing same

Provided is a hot dip zinc alloy plated steel sheet which is widely used in vehicles, domestic appliances, construction materials or the like and a method for manufacturing the same. A Zn—Al—Mg hot dip zinc alloy plating bath is used for manufacturing the hot dip zinc alloy plated steel strip, and a small amount of Ga or In is added to the plating bath for inhibiting an oxidation reaction of Mg in the plating bath so as to obtain excellent corrosion resistance and external surface of the plated steel sheet which is manufactured at this point.

Press-formed article and method for manufacturing same
09744744 · 2017-08-29 · ·

A method for manufacturing a press-formed article, said method comprising forming a galvanized steel sheet or an alloyed hot-dip galvanized steel sheet by hot press forming, wherein, after heating the steel sheet and holding the same, the forming is started at a temperature of 680-750° C. inclusive, while allowing liquid zinc to remain on the surface of the steel sheet, and the forming is performed while regulating the strain rate in a plastic deformation part of the steel sheet to 0.5 sec.sup.−1 or lower.

Press-formed article and method for manufacturing same
09744744 · 2017-08-29 · ·

A method for manufacturing a press-formed article, said method comprising forming a galvanized steel sheet or an alloyed hot-dip galvanized steel sheet by hot press forming, wherein, after heating the steel sheet and holding the same, the forming is started at a temperature of 680-750° C. inclusive, while allowing liquid zinc to remain on the surface of the steel sheet, and the forming is performed while regulating the strain rate in a plastic deformation part of the steel sheet to 0.5 sec.sup.−1 or lower.

HIGH-STRENGTH GALVANIZED STEEL SHEET
20170240999 · 2017-08-24 · ·

A high-strength galvanized steel sheet comprising a cold-rolled steel sheet, an intermetallic compound formed on the cold-rolled steel sheet, and a galvanizing layer formed on the intermetallic compound, the cold-rolled steel sheet having a specific composition and a microstructure having a martensite area ratio of 7% or more and less than 25% and a ferrite area ratio of 50% or more and which includes a base metal surface portion in which the amount of internal oxides per single side is 0.05 g/m.sup.2 or less.

HIGH-STRENGTH GALVANIZED STEEL SHEET
20170240999 · 2017-08-24 · ·

A high-strength galvanized steel sheet comprising a cold-rolled steel sheet, an intermetallic compound formed on the cold-rolled steel sheet, and a galvanizing layer formed on the intermetallic compound, the cold-rolled steel sheet having a specific composition and a microstructure having a martensite area ratio of 7% or more and less than 25% and a ferrite area ratio of 50% or more and which includes a base metal surface portion in which the amount of internal oxides per single side is 0.05 g/m.sup.2 or less.

Solder alloys and arrangements

A solder alloy is providing, the solder alloy including zinc, aluminum, magnesium and gallium, wherein the aluminum constitutes by weight 8% to 20% of the alloy, the magnesium constitutes by weight 0.5% to 20% of the alloy and the gallium constitutes by weight 0.5% to 20% of the alloy, the rest of the alloy including zinc.

Solder alloys and arrangements

A solder alloy is providing, the solder alloy including zinc, aluminum, magnesium and gallium, wherein the aluminum constitutes by weight 8% to 20% of the alloy, the magnesium constitutes by weight 0.5% to 20% of the alloy and the gallium constitutes by weight 0.5% to 20% of the alloy, the rest of the alloy including zinc.

Galvannealed steel sheet and method of manufacturing the same

A galvannealed steel sheet includes: a steel sheet; a coating layer on a surface of the steel sheet; and a mixed layer formed between the steel sheet and the coating layer, in which the mixed layer includes a base iron portion having fine grains having a size of greater than 0 μm and equal to or smaller than 2 μm, a Zn—Fe alloy phase, and oxides containing one or more types of Mn, Si, Al, and Cr, and in the mixed layer, the oxides and the Zn—Fe alloy phase are present in grain boundaries that form the fine grains and the Zn—Fe alloy phase is tangled with the base iron portion.
[Mn]+[Si]+[Al]+[Cr]≧0.4  (Expression 1)

Galvannealed steel sheet and method of manufacturing the same

A galvannealed steel sheet includes: a steel sheet; a coating layer on a surface of the steel sheet; and a mixed layer formed between the steel sheet and the coating layer, in which the mixed layer includes a base iron portion having fine grains having a size of greater than 0 μm and equal to or smaller than 2 μm, a Zn—Fe alloy phase, and oxides containing one or more types of Mn, Si, Al, and Cr, and in the mixed layer, the oxides and the Zn—Fe alloy phase are present in grain boundaries that form the fine grains and the Zn—Fe alloy phase is tangled with the base iron portion.
[Mn]+[Si]+[Al]+[Cr]≧0.4  (Expression 1)