Anodizing Test Results
Anodizing Test Illustrates Protection Levels
To provide specifiers with a practical anodizing performance expectation SAF conducted an Anodizing Test with Salt Spray on three aluminum samples for 1,000 hours. Resistance to salt spray is a true test of any finish for architectural metals. The SAF Salt Spray Test performed over time on different Anodizing Process Finishes documents the relative durability for each Anodizing Class.
The below two pictures show how anodized aluminum responds to a salt spray test on anodized samples, administered for 1,000 hrs in accordance with ASTM B117. The anodized aluminum panels show increasing levels of anodic coating. The thinnest anodized finish clearly shows the most pitting. The anodized coating thicknesses are 0.250, 0.50 and 0.8 mils. 0.50 is a AA Class II coating and 0.8 is a AA Class I coating. The Class I Anodizing shows little or no damage from the salt spray.