zinc phosphate post-treatment

[JTreglio]

We are working on a process to increase the corrosion resistance of hard coatings on steel. Our patented process involves three steps. Step one is to deposit by PVD a hard coating on the steel, TiN or the like. While these coatings are themselves very corrosion resistant, there are always holes in the coating where the base steel is exposed. In the second step, we phosphate the samples, in effect phosphating the exposed steel in the holes. In the third step, we apply an oil which is absorbed by the phosphate. The oil on the hard coating is then wiped away. In practice, the hard coating protects the phosphated, oiled surface in the holes, while the overall surface remains corrosion free.

We are not experts in phosphating or post-phosphate treatment, so would like to know if someone has a product that is particularly good to use on phosphated surfaces.

Jim Treglio
Molecular Metallurgy, Inc.

 

[unclesyd]

Normally you would apply a sealer over the phosphate to enhance it's durability. There are numerous maker of sealers for phosphate coatings.

You case is a little different and not knowing the end use it's a little hard to recommend a phosphate sealer or coating. If you need a lubricant look at EM Coatings or Tiodize.

http://www.em-coatings.com/

http://www.tiodize.com

If you can stand silicone I would look at Molykote Metal Protector by Dow.

http://www.dowcorning.com/content/molykote/

Another source of corrosion resistant coatings is
Cortec who's coatings I've used with phosphated surfaces.

http://www.cortecvci.com/index2.php