What is the impact of Lithium as impurity in Aluminium wrought alloys?

Dear ram13-ga:

Thank you for bringing your question to us. Please take a look at
these search results:

"Aluminum Alloys – Effects of Alloying Elements"
http://www.key-to-metals.com/ViewArticle.asp?ID=55

"The impurity level of lithium is of the order of a few ppm, but at a
level of less than 5 ppm it can promote the discoloration (blue
corrosion) of aluminum foil under humid conditions. Traces of lithium
greatly increase the oxidation rate of molten aluminum and alter the
surface characteristics of wrought products."

Generally, lithium impurities in aluminum alloy have a most noticiable
affect on the metal's surface appearance and tends to have a greater
impact on the product with each successive alloyed generation.

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future.

Regards;
tutuzdad-ga