Ben Hom wrote:

"Have freight cars made of aluminum ever had these problems?"

Yes. See Thompson/Church/Jones' Pacific Fruit Express on PFE's
experience with their early aluminum reefers.

Pages 171, 172: minor galvanic corrosion problems were observed, but both cars were considered by PFE to have performed satisfactorily. Both ended up being destroyed in wrecks, not scrapped due to any problems. No more were built because the cost was so great (Alcoa and Reynolds subsidized the material costs for the two experimental cars).
Alcoa prepared an interesting report summarizing experience with all the aluminum experimental cars built after World War II (including the Alton, GM&O, GN, etc. box cars). Conclusion was that there were minor improvements needed in separation of steel and aluminum, but that ALL CARS had performed well in service. The report does conclude with the observation that the weight saving must be of considerable economic importance to justify aluminum's cost relative to steel. In fact, it was decades later that the first aluminum coal cars were produced, for a combined reason of weight saving and corrosion resistance.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
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