Hard anodizing of AA2099-T8 aluminum‑lithium‑copper alloy: Influence of electric cycle, electrolytic bath composition and temperature

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178008 ◽

1990 ◽

Vol 48 (4) ◽

pp. 974-975

Author(s):

D.M. Jiang ◽

B.D. Hong

Keyword(s):

High Strength ◽

Deformation And Fracture ◽

Fracture Behaviors ◽

Aluminum Lithium ◽

Carbon Fiber Reinforced Composites ◽

Peak Aged ◽

Aluminum Lithium Alloys ◽

High Strength Aluminum Alloys ◽

Lithium Alloys ◽

Zr Alloy

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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Determining whiskering properties of tin-copper alloy solder-dipped platings

Periodica Polytechnica Electrical Engineering ◽

10.3311/pp.ee.2010-3-4.04 ◽

2010 ◽

Vol 54 (3-4) ◽

pp. 107

Author(s):

Barbara Horváth ◽

Balázs Illés ◽

Tadashi Shinohara ◽

Gábor Harsányi

Keyword(s):

Copper Alloy ◽

Alloy Solder

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A Romanesque crucifix from Macewen's Castle, Loch Fyne, Mid Argyll

Glasgow Archaeological Journal ◽

10.3366/gas.1989.16.16.81 ◽

1989 ◽

Vol 16 (1) ◽

pp. 81-84

Author(s):

J. G. Scott

Keyword(s):

Copper Alloy ◽

12Th Century ◽

Made In

Summary This copper alloy crucifix was found during excavation at Macewen's Castle in Argyll in 1968 and closely resembles others known to date from the 12th century; it may have been made in Belgium. The arms could have been bent back to aid concealment in the 17th or 18th centuries.

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