| 摘要 |
The object is to obtain a two-piece can which has sufficient can strength and excellent corrosion resistance and to provide a method for forming the two-piece can easily without generating cracks. The means to achieve the object is to manufacture the two-piece can by the method using a laminated steel sheet as the base material, having the steps of: drawing a cylindrical blank for several times to form a can body in a shape of cylinder integrated with bottom; forming a tapered part extending outward from the can body in the radial direction thereof at the tip of the opening of the can body; applying diametral reduction to the tapered part to the diameter of the can body; and applying diametral reduction to the opening side of the can body to a diameter smaller than the diameter of the can body, while satisfying the formulae (1) and (2). The two-piece can is obtained further by forming a dome protruding inside of the can at the can bottom, by trimming the opening of the can body, by applying diametral reduction to the opening of the can body, after the trimming, to a diameter smaller than the diameter of the can body, while satisfying the formulae (1) and (2), by forming a bead, after the diametral reduction, at the opening end of the can body, by heating the can to a temperature ranging from the glass transition point of the film of the laminated steel sheet to the melting point thereof + 30°C in the stage of the degree of working in a range of 0.2 <= d/R <= 0.5 and of 1.5 <= h/(R - r) <= 2.5, then by applying heat treatment giving rapid cooling to a temperature at or below the glass transition point within 30 seconds. 1.5 <= h/(R - r) (1) d/R <= 0.25 (2) where, h is the height from the can bottom to the tip of the opening, R is the circular blank positional radius, r is the radius of the can bottom, and d is the radius of the tip of the opening.
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