Hot rolling of sheet and strip: aluminium and aluminium alloys

Abstract

A modern hot line for hot-rolling aluminium and its alloys consists of a wide single-stand 4-high ‘breaking-down’ mill capable of cross-rolling long ingots of up to 660 mm thickness, and a multistand hot-finishing mill with integral slitter and coiler. The effects of weight per unit width, total width, and rolling speeds on the yield and productivity from such a mill are discussed. Metallurgical properties are controlled by ingot homogenization and roll-pass schedules, whereas surface quality is affected by ingot quality, scalping, and control of the roll coolant composition and temperature. Trends in customers’ requirements are for larger coils in common and complex alloys and for stronger, thinner material. It is suggested that in future large tonnages of limited ranges of such commodities may be fabricated on specialized hot mills with limited provision for cross rolling; alternatively, continuously cast slab may be converted to wide thin strip.