Durable Coating for a SST430 fastners exposed to gravel 1

[ToddRS]

I am looking for a durable coating that will bond well to SST430 and survive the SAE J400 Gravelometer testing. This would strictly be an aesthetic application as I'm not worried about corrosion resistance because of the inherent SST properties in this case. Basically looking for a black coating dull and/or shiny. This coating would be applied to screws and clips no larger than 1” to 2” in size. Any ideas for a durable type of coating would be greatly appreciated, non-oil and must be dry.

 

[TVP]

Potential options:

1. Order wire with MoS₂ lubricant/coating such as Knightcote from Cartech and leave the coating on the formed fasteners. It is a dark greyish black color, but may not perform well in a gravelometer.

2. Black oxide coating. Chipping resistance isn't very good for this either.

http://www.swdinc.com/BlackOxideBasics.html

3. Black PTFE coatings such as DuPont Teflon, one of the Xylan coatings from Whitford, etc. Good bonding is key to chipping resistance.

4. Any other black organic coating.