Metallurgical Failure Analysis
3568 Caminito El Rincon, #93
San Diego, California, 92130
209 367-1398 - Email: firstname.lastname@example.org
Mark Douglas Bell, PE
Consulting Metallurgical Engineer
|Brasses are the most famous alloys for de-alloying. This corrosion happens when one phase or alloying element is preferentially lost from the matrix. In some instances there is no warning of the loss and the failure is sudden. Aluminum may be lost from aluminum bronze, carbon (in form of graphite) can be lost from cast iron and zinc can be lost from high zinc alloys of brass.
In World War I the British Fleet had more battleships out of service due to desertification in their boiler tubes than were lost due to action with the German Fleet. Good material selection, alloy additions, minimizing other phases and heat treating are used to control de-alloying.
Click here for a report on dealloying (turnbuckle failure) (pdf).