Effects of the nozzle shape on surface condition and geometry of wide aluminum alloy foils rapidly solidified by single roll method.

Geometric uniformity in the cross section of Al-12mass% Si alloy wide foils rapidly solidified by a single roll method depends on the slit shape of nozzle. The slit shape including slit clearance, slit length, slit surface, slit outlet and slit inlet was controlled. Thickness of preferable foils depends on slit clearance. Nonuniformity of slit clearance affects the shape of wide foils in the cross section. The irregularity of slit surface has little effect on the shape of thick foils in the cross section, but has a detrimental effect on the surface appearance of thin foils. Neither slit inlet nor slit length has an influence on the foil shape. Shape factors for the slit which determine the most favorable ejection pressure of the metal for marking preferable foils include uniformity of slit clearance, sound slit-tip free from cracks and suitable slit clearance corresponding to foil thickness.