摘要 |
1,271,185. Rolling. BETHLEHEM STEEL CORP. 23 March, 1970 [24 March, 1969], No. 13893/70. Heading B3M. [Also in Division C7] A composite work roll for cold rolling has a low alloy cast iron core and a chill surface area comprising: the balance, apart from impurities, being Fe. The east rolls may be heated to 850‹ F., held for 4 hours, cooled to 100‹ F. at 50‹ F./hr., reheated to 500‹ F., held for 4 hours, and then cooled to ambient temperature at 50‹ F./hr.; or cooled to - 100‹ F., stress relieved at 500‹ F. at the rate of 1 hour/inch of thickness and then cooled to ambient temperature. The rolls are less susceptible to bruising marking and spalling than prior art rolls. The core of the roll may comprise: the balance, apart from impurities, being Fe. |