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Comm. Equipment Mfgr. Asks How Good is NH-35?

I have been researching the NH-35 chemical Conversion Finish for magnesium...I have been receiving conflicting information as to its suitability for corrosive environments (salt fog)...I have received information stating it is an excellent corrosion resistant coating...and others ranging from "Good in Mild Environments and for Splash Resistance" to "Improper or Wrong Coating for Harsh Environments..."

Could you provide some insight as to NH-35s actual nature for harsh environments and general corrosion protection capability?

Kim G. Farral
OEM Communications Equipment - Ft. Wayne, Indiana, USA
2003

Treating Mg with NH35 only is not sufficient for preventing corrosion in salt fog environments. NH35 is meant to be a pre-treatment for organic coatings (powder, electrocoat, etc.) that will subsequently be exposed to aggressive environments such as salt fog. Mg with NH35 and a 25 micron E-coat or a > 50 micron coating of powder can withstand 480 hours of salt fog with no corrosion to intact surfaces, and little or no creep-back from scribed surfaces. Contact Hydro Magnesium in Livonia, MI (Norsk Hydro is the NH in NH35) for more information.

Toby Padfield
Automotive module supplier - Michigan
2003