Results of Some Marine-Atmosphere Corrosion Tests on Magnesium-Lithium 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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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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NOAA/CMDL trace halocarbon data in the marine atmosphere, surface, and subsurface waters measured in 1994-2004

Carbon Dioxide Information Analysis Center ◽

10.3334/cdiac/otg.noaa_cmdl_1994_2004 ◽

2004 ◽

Author(s):

J.W. ELKINS, ◽

J.H. BUTLER, ◽

B.D. HALL, ◽

S.A. MONTZKA,

Keyword(s):

Marine Atmosphere ◽

Subsurface Waters ◽

Surface And Subsurface Waters

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Mcc Corrosion Tests at Reference Testing Conditions for A27 Cast steel in Hanford Ground Water

MRS Proceedings ◽

10.1557/proc-84-215 ◽

1986 ◽

Vol 84 ◽

Author(s):

M.D. Merz ◽

F. Gerber ◽

R. Wang

Keyword(s):

Pacific Northwest ◽

Pressure Vessel ◽

Static Pressure ◽

Cast Steel ◽

Statistical Treatment ◽

Testing Conditions ◽

Corrosion Tests ◽

Corrosion Rates ◽

High Level Nuclear Waste ◽

High Level

AbstractThe Materials Characterization Center (MCC) at Pacific Northwest Lab- oratory is performing three kinds of corrosion tests for the Basalt Waste Isolation Project (BWIP) to establish the interlaboratory reproducibility and uncertainty of corrosion rates of container materials for high-level nuclear waste. The three types of corrosion tests were selected to address two distinct conditions that are expected in a repository constructed in basalt. An air/steam test is designed to address corrosion during the operational period and static pressure vessel and flowby tests are designed to address corrosion under conditions that bound the condi ring the post-closure period of the repository.The results of tests at reference testing conditions, which were defined to facilitate interlaboratory comparison of data, are presented. Data are reported for the BWIP/MCC-105.5 Air/Steam Test, BWIP/MCC-105.1 Static Pressure Vessel, and BWIP/MC-105.4 Flowby Test. In those cases where data are available from a second laboratory, a statistical analysis of interlaboratory results is reported and expected confidence intervals for mean corrosion rates are given. Other statistical treatment of data include analyses of the effects of vessel-to-vessel variations, test capsule variations for the flowby test, and oven-to-oven variations for air/steam tests.

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