ZnCoat, ZnCoat Yellow, ZnCoat Black
Taking anti-corrosion surface treatment to the next level of performance and quality

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Bimetallic Corrosion Resistance Test Results

Bimetalic Corrosion occurs when two metals with different potentials are in contact with each other.  This can result in premature failure, also known as Galvanic corrosion.  Galvanic potential differences between Zinc and Aluminum cause bimetallic corrosion to occur when these materials are mated together. The result is pitting corrosion of the Aluminum surface. ZnCoat® is an advanced coating containing both Zinc and Aluminum. The combination of Zinc and Aluminum in ZnCoat® greatly reduces the bimetallic cell, allowing ZnCoat® fasteners to be mated to Aluminum surfaces without compromising quality.


ZnCoat® Yellow

Zinc Plating / Trivalent

240 h SST

240 h SST

No pitting of the Aluminum substrate 

Medium to dense pitting of the Aluminum substrate 

Magnification of Aluminum substrate

Magnification of Aluminum substrate

Tested in SST for 240 hours per ASTMB117.  Washers were rinsed, dried & sandblasted.


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