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Molybdenum Phosphate plating/coating on steel sheetmetal

I am the Mechanical engineering Supervisor for R & D new product development. Presently we plate our steel units with Zinc Chromate finish and would be interested in alternate plating/coating materials.

In reference to an article in Sep 1999 Assembly magazine, entitled "The Signal for Success", I learned of a company that has replaced Zinc chromate with Molybdenum Phosphate plating. The article notes cost savings, environmental issues, and superior shielding benefits, via the Molybdenum Phosphate plating. I am looking for information & specifications for the Molybdenum Phosphate plating. Also, I would be open to talking with sales/technical reps for obtaining samples and or plating our steel sheet metal product for evaluation. Thanks, Alan Wardlow

Alan Wardlow
- Petaluma, California
1999

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If there is a molybdenum phosphate plating, it is extremely new. Moly can be plated , with difficulty, as an alloy with things like nickel, cobalt, etc., but there was no known commercially available way to plate moly a few years ago.

Manganese phosphate is a phosphate coating and not a plating that has been around for years, primarily for a break in compound on friction surfaces. It is normally a coarse rough dark black finish that has good wear properties and decent rust prevention capabilities. It is much higher priced than iron or zinc phosphate.

James Watts
- Navarre, Florida
1999

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Alan Emailed me the web site of the company. They are touting a molybdenum infused iron phosphate. I have no idea of what THEY mean by infused and they certainly do not give any details. I am suspect of new products that are full of boasts and are very light on technical data or operating conditions. Molybdenum disulfide has been around for years as a dry film lubricant that is a second operation after phosphating and works well.

It is possible that they did actually develop a means of having some co-deposit with the phosphate, but I would approach it with extreme caution, and run several sets of test parts.

James Watts
- Navarre, Florida
1999