| 摘要 |
A continuous hot-dip coating line, whereby an aluminum-zinc alloy coating, comprising from 25% to 75% aluminum by weight, is applied to a steel strip, includes an induction furnace whereby the coated strip is heated to a treatment temperature within the range of from 165 DEG C. to 275 DEG C., preferably about 200 DEG C. The strip emerging from the furnace is coiled directly at that treatment temperature into close wound coils having a mass of at least 2 tons, and the coils are allowed to cool in still air at the ambient indoor temperature pertaining, at a rate of no more than 40 centigrade degrees per hour, for all but a predetermined number (typically less than four, usually only one) of the outer turns of the coil which are scrapped, to enhance the ductility of the coating on the remainder of the coil. If the treated coated strip is subsequently painted, the paint is cured at a peak metal temperature of less than 240 DEG C. |
