The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Wear Coatings for Aluminum Bearing Surface

2000

Hi!

I'm trying to solve a wear problem that involves a plastic substrate with small alumina particles embedded in it running over an aluminum surface. The substrate only touches the aluminum surface intermittently at the edges of the plastic, and this is where the wear occurs. I've tried anodizing the aluminum (~.001" thick), but that seems to wear fairly quickly. I'm considering trying a much harder coating, such as TiN or some sort of PVD diamond, but I am concerned that because these coatings are so much thinner than the anodize I won't gain much net life. Does anyone have an idea if, and if so how much, increase in wear life I might expect from one of these harder, thinner coatings? Or have any ideas on other coatings that I might try?

Thanks so much!

Jeannie Yoo
- Minneapolis, Minnesota

---

The standard substrate temperature for TiN and most other PVD coatings is 450 °C -- far too high to coat aluminum. While we are depositing Cr2N on aluminum at 120 C, and have deposited TiN at 150 C, I would suggest you look at either electroless nickel plating or thermal spray.

Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover
San Diego, California
2000