ALUMINUM-LITHIUM ALLOYS, AND METHODS FOR PRODUCING THE SAME

摘要

New Al—Li alloy bodies and methods of producing the same are disclosed. The new Al—Li alloy bodies may be produced by preparing the aluminum alloy body for post-solutionizing cold work, cold working by at least 25%, and then thermally treating. The new Al—Li alloy bodies may realize improved strength and other properties.

主权项

1. A method comprising:
(a) preparing an aluminum alloy strip for post-solutionizing cold work,
(i) wherein the aluminum alloy strip includes 0.25-5.0 wt. % lithium,(ii) wherein the preparing step comprises continuously casting the aluminum alloy sheet, the continuously casting step comprising:
(A) delivering molten aluminum metal comprising the 0.25-5.0 wt. % lithium to a pair of spaced apart rotating casting rolls defining a nip therebetween;(B) advancing the metal between surfaces of the casting device rolls, wherein the advance comprises:
(I) first forming two solid outer regions adjacent surfaces of the casting device rolls;(II) second forming a semi-solid inner region containing dendrites of the metal;(III) wherein the inner region is located between the two outer concentration regions;(IV) wherein the first forming and second forming steps are completed concomitant to one another;(V) breaking the dendrites in the inner region at or before the nip; and(C) solidifying the semi-solid inner region to produce the aluminum alloy body comprised of the inner region and the outer regions;(iii) wherein the preparing step comprises solutionizing of the aluminum alloy strip; (b) after the preparing step (a), cold working the aluminum alloy sheet by at least 25%; and (c) after the cold working step (b), thermally treating the aluminum alloy sheet; wherein the cold working and the thermally treating steps are accomplished to achieve an increase in long-transverse tensile yield strength as compared to a reference-version of the aluminum alloy body in the as cold-worked condition.