Filiform Corrosion Resistance of Painted Automotive Body Sheet

Accelerated and outdoor exposure studies were conducted on three automotive body sheet alloys-2036, 2008, and 6009-in order to compare their filiform corrosion resistance after painting. The effect of variations in pretreatment and sanding prior to painting were studied and the amount of filiform corrosion was quantified. Both spray and immersion pretreatments were evaluated. A field survey of automobiles with 2036 alloy aluminum hoods in service for up to 10 years was conducted.