Accession Number : AD0787027

Title :   Development of an Al-Mg-Li Alloy.

Descriptive Note : Final technical rept. 8 Feb 73-7 Feb 74,

Corporate Author : ALUMINUM CO OF AMERICA ALCOA CENTER PA PHYSICAL METALLURGY DIV

Personal Author(s) : Evancho,Joseph W.

Report Date : 24 JUN 1974

Pagination or Media Count : 186

Abstract : Four Al-Mg-Li alloys were investigated for potential use in high performance aircraft. Ingot casting was very difficult. Fabricating was also difficult; however, a limited amount of sheet and some upset forgings were fabricated. Solution heat treatment practices providing highest strength were determined and aging surveys for each alloy were conducted. Cold working between solution heat treatment and artificial aging significantly affected response to artificial aging. Elastic moduli were higher and densities were lower than those of other aluminum alloys. Elevated temperature strengths were comparable to those of 2020-T6. Resistance to exfoliation corrosion was comparable to 7075-T76 sheet, but the alloys were highly susceptible to stress-corrosion cracking. Toughness of these alloys was also very low. (Modified author abstract)

Descriptors :   *Aluminum alloys, *Magnesium alloys, *Lithium alloys, *Casting alloys, Forging, Corrosion, Density, Elastic properties, Heat treatment, Toughness, Fabrication, Aircraft

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE