In manufacturing aluminized steel sheet that uses aluminum killed steel or the like as the material, improvement is directed to securely enhance both sheet workability and plated layer's anti-peeling characteristics.
Low carbon content aluminum killed steel sheet that contains, in weight percent, 0.1% or less carbon, 0.05% or less aluminum, 0.003-0.02% nitrogen, and in addition, maintains an equation of N≥0.5 × aluminum weight % is plated in molten aluminum or aluminum alloy to produce aluminized steel plate material. Aluminized steel sheet so produced is then cold rolled at the reduction rate of 30-95%, followed by annealing at 450-650°C not only to provide the sheet with high workability but also give its plated layer excellent anti-peeling resistance. It is also practicable on behalf of annealing, to heat up to and hold at a temperature range of 350-450°C for a preset time and then resume heating up to and holding at a temperature range of 450-650°C. Besides, it is suitable to have the skinpass rolled, or cold rolled at the reduction rate of 25% or less.
KAWAMOTO AKITO
HAMANAKA SEIICHI
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