Process and products for the continuous casting of flat rolled sheet
AssigneeAlcoa Inc.
InventorsHarry R. Zonker, Stephen F. Baumann, Robert E. Sanders, W. Bryan Steverson
Life of this patent
Estimating the term…
Abstract
The invention hereof is directed to a continuous casting of flat rolled sheets selected from automotive sheet, can body sheet, and endstock which exhibits properties comparable to the same products made from World Class Ingot. A preferable embodiment for the continuous caster is a vertical continuous caster.
Claims3
A method comprising casting an aluminum alloy as a continuous cast slab to a thickness of 17 to 25 mm, hot rolling said slab in a temperature range from 370° to 510° C., reducing said slab to within the range of 50 to 90% of its original thickness to sheet thickness said sheet exiting the hot roll within a temperature range of about 200° to 400° C., cold reducing said sheet within 30 to 90% of the hot band thickness, subjected to an intermediate continuous anneal at 525° to 580° C. sufficient to recrystallize the microstructure followed by a quench to make a quenched product, cold reducing said quenched product by 25 to 80% and batch stabilized between 95° to 200° C. to make a batch stabilized sheet product wherein said batch stabilized sheet product consists essentially of an aluminum alloy composition of 0.8 to 1.5 wt % magnesium, 0.7 to 1.5 wt % manganese, 0.05 to 0.50 wt % copper, 0.2 to 0.7 wt % iron, 0.10 to 0.40 wt % silicon and the balance being aluminum and incidental elements and impurities wherein said product comprises a bake yield strength of at least 258 Mpa, a 45° earing in percent of no more than 2.7, and a maximum strength loss of no more than 12.4% due to paint bake.
A method comprising casting an aluminum alloy as a continuous cast slab to a thickness of 9 to 23 mm, hot rolling said slab in a temperature range from 200° to 400° C., hot reducing said slab to within the range of about 50 to 90%, said slab exiting the hot mill in a temperature range between 230° to 290° C. then subjected to an optional intermediate batch anneal with a soak temperature of about 325° to 510° C. to effect a recrystallization, cold reducing said slab from the hot band thickness from about 25 to 90% making a sheet product, heat treating said sheet solution from about 525° to 580° C. sufficiently long to dissolve a portion or more of soluble second phase particles and subsequently quenching to retain a supersaturated solid solution wherein said sheet consists essentially of 0.2 to 1.5 wt % silicon, about 0.3 to 1.5 wt % magnesium, optionally about 0.05 to 0.9 wt % manganese, about 0.05 to 1.2 wt % copper, less than 0.30 wt % iron with the balance being aluminum and incidental elements and impurities wherein said sheet has a minimum bend radius after a 10% pre-stretch is 0.45 longitudinal and 0.79 transverse.
A method comprising casting an aluminum alloy as a continuous cast slab to a thickness of 17 to 23 mm, hot rolling said slab in a temperature range from 370° to 510° C., reducing said slab to within the range of 50 to 90% of its original thickness to sheet thickness, said sheet exiting the hot roll within a temperature range of about 200° to 400° C., said sheet optionally provided an intermediate anneal within the temperature range of 325° to 510° C. cold reducing said sheet from about 25 to 90%, recrystallizing said sheet optionally self-stabilizing said sheet by heating and soaking said sheet for about 2 hours at 95° to 200° C. wherein said sheet consists essentially of 3.0 to 5.0 wt % magnesium, about 0.05 to 0.6 wt % manganese, about 0.05 to 0.5 wt % copper, less than 0.40 wt % iron less than 0.30 wt % Si the balance being aluminum and incidental elements and impurities wherein said sheet has a stabilized yield strength of 341 MPa, a 45° earing of no more than 5.9%, and a bend rating of 5.5.
Dependencies are inferred from the claim text.