Deformation and fracture behavior of an Al-Li-Cu-Mg-Zr alloy 8090

Aluminum-lithium alloys have been recently got strong interests especially in the aircraft industry. Compared to conventional high strength aluminum alloys of the 2000 or 7000 series it is anticipated that these alloys offer a 10% increase in the stiffness and a 10% decrease in density, thus making them rather competitive to new up-coming non-metallic materials like carbon fiber reinforced composites.The object of the present paper is to evaluate the inluence of various microstructural features on the monotonic and cyclic deformation and fracture behaviors of Al-Li based alloy. The material used was 8090 alloy. After solution treated and waster quenched, the alloy was underaged (190°Clh), peak-aged (190°C24h) and overaged (150°C4h+230°C16h). The alloy in different aging condition was tensile and fatigue tested, the resultant fractures were observed in SEM. The deformation behavior was studied in TEM.

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Precipitation in Al-Li-Zr alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121338 ◽

1992 ◽

Vol 50 (1) ◽

pp. 186-187

Author(s):

D.M. Vanderwalker

Keyword(s):

Fracture Toughness ◽

Precipitation Hardening ◽

Weight Ratio ◽

High Strength ◽

Transmission Electron ◽

Water Quench ◽

Aluminum Lithium ◽

Aluminum Lithium Alloys ◽

Lithium Alloys ◽

Zr Alloys

Aluminum-lithium alloys have a low density and high strength to weight ratio. They are being developed for the aerospace industry.The high strength of Al-Li can be attributed to precipitation hardening. Unfortunately when aged, Al-Li aquires a low ductility and fracture toughness. The precipitate in Al-Li is part of a sequence SSSS → Al3Li → AlLi A description of the phases may be found in reference 1 . This paper is primarily concerned with the Al3Li phase. The addition of Zr to Al-Li is being explored to find the optimum in properties. Zirconium improves fracture toughness and inhibits recrystallization. This study is a comparision between two Al-Li-Zr alloys differing in Zr concentration.Al-2.99Li-0.17Zr(alloy A) and Al-2.99Li-0.67Zr (alloy B) were solutionized for one hour at 500oc followed by a water quench. The specimens were then aged at 150°C for 16 or 40 hours. The foils were punched into 3mm discs. The specimens were electropolished with a 1/3 nitric acid 2/3 methanol solution. The transmission electron microscopy was conducted on the JEM 200CX microscope.

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Peculiarities of high-strength aluminum-lithium alloys laser weldin

Proceedings of VIAM ◽

10.18577/2307-6046-2016-0-10-7-7 ◽

2016 ◽

pp. 7-7 ◽

Cited By ~ 3

Author(s):

V.I. Lukin ◽

◽

E.N. Ioda ◽

M.D. Panteleev ◽

A.A. Skupov ◽

...

Keyword(s):

High Strength ◽

Aluminum Lithium ◽

Aluminum Lithium Alloys ◽

Lithium Alloys

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Aluminum Lithium Alloys (Al-Li-Cu-X)-New Generation Material for Aerospace Applications

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.440.104 ◽

2013 ◽

Vol 440 ◽

pp. 104-111 ◽

Cited By ~ 6

Author(s):

Bilal Ahmed ◽

Su Jun Wu

Keyword(s):

Aluminum Alloys ◽

High Strength ◽

Cost Effective ◽

Weight Percent ◽

Atomic Weight ◽

Physical Metallurgy ◽

Potential Candidate ◽

Aluminum Lithium ◽

Aluminum Lithium Alloys ◽

Lithium Alloys

Significant advantages in weight reduction and increased strength have place advanced aluminum-lithium alloys at forefront of aerospace materials research. These alloys are being developed to fulfill the ever increasing need for high strength, high properties, light weight and cost effective for aerospace industry. Conventional aluminum alloys has long been in service for aerospace application. The addition of lithium to aluminum improves modulus and decrease density compared to conventional aluminum alloys. Atomic weight of lithium is 7 mass units compared to aluminum 23 mass units, hence there is density reduction of about 3% for each weight percent addition of lithium and about 6% increase in Youngs modulus. In principle weight saving for aerospace structural parts could reach up to 15 %. This paper examines effect of lithium addition on properties, physical metallurgy; various phases developed during processing of these alloys. The addition of Lithium to aluminum form coherent, low density Al3Li (δ׳) precipitates. However the binary alloys have poor mechanical properties which are attributed to strain localization and shearing of soft Al3Li (δ׳) precipitates. This problem has been solved by development of ternary and quaternary alloys containing copper and magnesium. In all aluminum-lithium alloys, small addition of zirconium or scandium is done to improve recrystallization. The new developed aluminum lithium alloys series Al-Li-Cu-X are potential candidate to replace existing conventional alloys in terms of enhanced properties with reduced density.

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Characterization of Rapidly Solidified Aluminum-Lithium Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117224 ◽

1985 ◽

Vol 43 ◽

pp. 26-29

Author(s):

Frank W. Gayle ◽

John B. VanderSande

Keyword(s):

Aluminum Matrix ◽

Spherical Shape ◽

High Strength ◽

Zone Formation ◽

Free Zone ◽

Aluminum Lithium ◽

Slip Planes ◽

Aluminum Lithium Alloys ◽

Rapidly Solidified ◽

Lithium Alloys

Aluminum-lithium alloys are presently the subject of much research due to the effectiveness of lithium in reducing density, raising elastic modulus and providing for high strength. The strengthening precipitate is the metastable, L12-ordered Al3Li (Cu3Au prototype), or δ'. In binary alloys, δ’ precipitates homogeneously with a spherical shape, coherent with the aluminum matrix. These lithium-containing alloys suffer from poor ductility and fracture toughness, however, which has been attributed to 1) the shear-able nature of the δ’ precipitate, resulting in work softening and slip localization on the relevant slip planes, and 2) precipitate free zone formation along high angle grain boundaries.In a previous paper we proposed that Zr could partially substitute for Li in δ', resulting in a ternary Al3(Li,Zr) phase, which we call δ”. It was anticipated that such a phase would be more resistant to dislocation shear than δ’ from observation of deformation behavior of Al-Zr alloys containing the coherent L12-ordered Al3Zr precipitate.

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Plasma welding of high-strength aluminum alloys

Science intensive technologies in mechanical engineering ◽

10.30987/2223-4608-2020-7-3-11 ◽

2020 ◽

Vol 2020 (7) ◽

pp. 3-11

Author(s):

Viktor Ovchinnikov ◽

Ruslan Rastopchin

Keyword(s):

High Strength ◽

Plasma Welding ◽

Tungsten Electrode ◽

Fine Grained ◽

Hollow Anode ◽

Aluminum Lithium ◽

Pulse Feed ◽

Fine Grained Structure ◽

Aluminum Lithium Alloys ◽

High Strength Aluminum Alloys

On the analysis basis of trends in the development of aluminum alloy plasma welding it is shown that in most cases for critical structures there is used welding with a non-consumable electrode on reversed polarity with adding wire material. A welding method with a hollow anode to increase non-consumable tungsten electrode durability is described. It is shown that to increase quality of welded joints in aluminum-lithium alloys the application of plasma-forming gas programmable pulse feed has promising outlooks. In this case side by side with the decrease of such defects as pores and oxide films the obtaining of more fine-grained structure in metal seams is marked.

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