Defects Affecting Extrusion - Corrosion

摘要

The 11th article in this extrusion defect series addresses corrosion aspects on mill finish extrusion. Inter-granular, stress corrosion, or exfoliation corrosion can be encountered in a number of aluminum alloys and can result from a wide variety of causes and conditions, most of which involve some degree of acidic environment (though not necessarily strongly acidic) and a marked "structure-sensitive" element. In dilute AlMgSi alloys of the AA6063 type, superficial forms of corrosion can have a detrimental effect on the cosmetic quality, especially after surface finishing.