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Stress-corrosion behavior of aluminum-lithium alloys in aqueous salt environmentsThe stress corrosion susceptibility of two powder metallurgy (P/M) alloys, Al-Li-Cu and Al-Li-Cu-Mg; two mechanically attrited (M/A) alloys, Al-Li-Cu and Al-Li-Mg; and two wrought, ingot alloys, X-2020 and AA7475, are compared. Time-dependent fracture in an aqueous sodium chloride environment under alternate immersion condition was found to vary significantly between alloys. The stress corrosion behavior of the two powder metallurgy processed alloys was studied in detail under conditions of crack initiation, static crack growth, and fatigue crack growth. A variety of stress corrosion tests were performed including smooth surface, time-to-failure tests; potentiostatic tests on smooth surfaces exposed to constant applied strain rates; and fracture mechanics-type tests under static and cyclic loads. Both alloys show surface pitting and subsequent intergranular corrosion. Pitting is more severe in the magnesium-bearing alloy and is associated with stringer particles strung along the extrusion direction as a result of P/M processing.
Document ID
19850044981
Document Type
Conference Paper
Authors
Pizzo, P. P. (San Jose State University San Jose, CA, United States)
Galvin, R. P. (San Jose State Univ. CA, United States)
Nelson, H. G. (NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1984
Subject Category
METALLIC MATERIALS
Meeting Information
Aluminum-lithium alloys II(Monterey, CA)
Funding Number(s)
CONTRACT_GRANT: NCC2-155
Distribution Limits
Public
Copyright
Other