Corrosion Resistance

No other coating can provide the level of corrosion resistance offered by Tagnite and is the only magnesium coating with significant inherent corrosion resistance. Shown below are photos of magnesium test plates after exposure to salt spray (ASTM B117). The plates are made from alloy ZE41A and, to ensure consistency, came from the same melt number. The salt spray testing was performed by a third party. The Dow 17 and HAE coatings were applied by an approved source.

Prior to salt spray testing, a layer of tape was applied to the top of the plates in an effort to preserve the plate number stamped in the upper left hand corner. The tape worked well on the plates exposed for 168 hours. However, on the Dow 17 and HAE coated plates exposed for 336 hours, corrosion migrated under the tape.

Plates coated with thin (Type I) coatings were exposed to salt spray for 168 hours. Plates coated with thick (Type II) coatings were exposed to salt spray for 336 hours. Notice that Tagnite coated plates have substantially fewer corrosion sites or pits. Also note the depth of pits on the HAE and Dow 17 plates are significantly deeper than pits on the Tagnite coated plates.

Click on the following images to see larger and more detailed image.

AGNITE-8200Type I		HAE Type I		Dow 17 Type I
Coating Thickness: 0.39mil		Coating Thickness: 0.39mil		Coating Thickness: 0.39mil
Alloy: ZE41A		Alloy: ZE41A		Alloy: ZE41A
168 Hours ASTM B117		168 Hours ASTM B117		168 Hours ASTM B117

 

TAGNITE-8200 Type II		HAE Type II		Dow 17 Type II
Coating Thickness: 0.83mil		Coating Thickness: 0.83mil		Coating Thickness: 0.83mil
Alloy: ZE41A		Alloy: ZE41A		Alloy: ZE41A
336 Hours ASTM B117		336 Hours ASTM B117		336 Hours ASTM B117