Study of Localized Corrosion in Aluminum Alloys by the Scanning Reference Electrode Technique

NASA/TP-3562, Danford, M.D., Study of Localized Corrosion in Aluminum Alloys by the Scanning Reference Electrode Technique, Materials and Processes Laboratory, Science and Engineering Directorate NASA Marshall Space Flight Center, AL 35812, May 1995, pp. 12, Format(s): PDF 867k

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Localized corrosion in 2219-T87 aluminum (Al) alloy, 2195 aluminum-lithium (Al-Li) alloy, and welded 2195 Al-Li alloy (4043 filler) have been investigated using the relatively new scanning reference electrode technique (SRET). Anodic sites are more frequent and of greater strength in the 2195 Al-Li alloy than in the 2219-T87 Al alloy, indicating a greater tendency toward pitting for the latter. However, the overall corrosion rates are about the same for these two alloys, as determined using the polarization resistance technique. In the welded 2195 Al-Li alloy, the weld bean is entirely cathodic, with rather strongly anodic heat affected zones (HAZ) bordering both sides, indicating a high probability of corrosion in the HAZ parallel to the weld bead.

Keywords:	slow strain rate technique, 2219-t87 al alloy, 2195 al-li alloy, 2195 al-li alloy welds
CASI Document ID Number:	96N13077
Subjects:	Chemistry and Materials: Metals and Metallic Materials: Aluminum
ID Code:	277
Deposited On:	26 June 2002