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Zirconium nitride coating reaction with industrial alcohol

December 19, 2009

I am a engineer in a vacuum plating company. We can do zirconium nitride (ZrN), titanium nitride (TiN), titanium carbide (TiC), and TiCN, and our coating are pretty good. But recently, a problem started to perplex us concerning the reactions of coatings with industrial alcohol.

ZrN coating immersion in Industrial alcohol (IC) resulted in the spallation and removal of coatings in 2 hr, and ..
For short,
ZrN + IC = spalling in 2 hr
TiN + IC = OK in 10 hr
TiC + IC = OK in 10 hr
TiCN + IC = spalling in 2 hr

My speculation is: Pure Zr and Ti are incorporated in the ZrN and TiN coatings, and Zr is more active than Ti. So both of them can react with the some other species in industrial alcohol, leading to spalling.
If the speculation works, but how to explain TiCN is not good?
I really appreciate your comments.

Junwei Wu
engineer - Shenzhen, China

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Perhaps it has something to do with the substrate and the interface between the coating and the substrate. IC could be seeping through the pores in the coating and interacting with the interfacial layer ( which could be an impurity ) resulting in the delamination of the coating.

H.R. Prabhakara - Consultant
Bangalore Plasmatek - Bangalore Karnataka India
December 22, 2009

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First of two simultaneous responses --

We've never seen any effect of alcohol on PVD coatings, especially ZrN, but we've never tried soaking them in alcohol. It could be an important discovery if the alcohol removes ZrN, as the coating is pretty impervious to hydrogen peroxide used to strip TiN.

Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover
San Diego, California
January 1, 2010

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Second of two simultaneous responses -- January 4, 2010

Thanks.
Unfortunately, all coating can't reach 100% density, which is our goal:)
What I am worrying about is some caustic impurities incorporated into the industrial alcohol.

Junwei Wu
- Shenzhen, China