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Looking for low cost, low performance anti-corrosion coating for steel

Our company currently manufactures metal stampings for the automotive industry. In one of our product lines, an expandable seal is heat bonded to the stamping before it is shipped to the customer. Currently we have to use galvanized steel in order to keep the part from rusting until it is placed in the vehicle. Once it is assembled into the car and goes through the e-coating process, rust is no longer an issue. Also, the process of heat bonding the seal to our stamping has always been a challenge to control in production and is in need of improvement. We feel that our stampings could be much more competitive if we could find a low cost rust preventative coating that could be applied to the steel right at our stamping presses that would also aid in the adhesion of the seal to our stamping. If you have any suggestions or can point me in the right direction, it would be greatly appreciated. Thank you.

Steve Porter
manufacturing - Almont, Michigan, USA
1998

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A coating that would be simple and mildly corrosion resistant and likely to be compatible with the e-coat process would be phosphatizing. You could do anything from a simple 3-stage iron phosphate (clean-phos, rinse, rinse) if your needs truly are minimal, through a more thorough 5-stage iron phosphatizing, or even 7-stage zinc phosphatizing followed by oiling.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

I would vote for a fine crystal zinc phosphate run on a smaller to medium barrel phosphate line. Would consider a chrome seal if compatible. A non chrome seal would simplify the waste treatment if it was compatible. Oil , IF any, would have to be done after the bonding and would have to be compatible with the expandable seal and the adhesive.

James Watts
- Navarre, Florida
1998

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We suggest you try our Rusteco Gel. Spray apply to the metal and washes off when not needed any more. Also acts as primer and provides excellent adhesion to any coating.

Michael H. Nahm
1998

Have you considered using copper coated steel?

Larry Martin
- Salt Lake City, Utah
2000