A Problem about Zinc Coating
04-10-2008, 09:02 AM,
A Problem about Zinc Coating
Dear Mr. Gordon,

I have prepared a zinc coating on a steel substrate for corrosion resistance with arc wire spray process, and it has been put in the air for 3 months.
I want to know how much the coating was corrupted. So I dipped it in NaOH solution in order to solve something like basic zinc carbonate or zinc oxide. But after a day I found that the coating was bubbly. I consider that the probable reason is a part of zinc oxide, which had been produced during spraying process, was solved.

I wonder if there are some good methods to gain my ends.
Looking forward to your help.


04-14-2008, 03:20 PM,
RE: A Problem about Zinc Coating
Hi Joylinkwu

Sign0016 to the Surface Engineering Forum.

In the typical environments these coatings are employed, I would expect to see very little degradation of the coating in a 3 month period and measuring the effect I think will be very difficult. Chemical analysis of the coating will always be clouded by the background of oxidation from the spraying process. Measuring mass difference may be a better approach, but this is complicated by the fact that corrosion products retained in or on the coating may show increasing mass initially. Electro-chemical methods are used for shorter term testing /monitoring, but I think for really meaningful results you will need something like this (link dead) Happy0193 to do this yourself may take the rest of your working life Happy0193
05-21-2008, 03:15 PM,
RE: A Problem about Zinc Coating

I was just thinking what would happen if we use a protective gas instead of air?

Well it would not be cost effective for sure, but i assume it would work if you are so keen on decreasing the amount of oxide in the sprayed metal formed during spraying...

Another question is, is not the amount of oxides of TS metal formed during the operation negligable as there is no sufficient time for the kinetics of oxide formation?

All the best...
05-30-2008, 04:05 PM, (This post was last modified: 05-30-2008, 04:07 PM by ThermalMan.)
RE: A Problem about Zinc Coating
You could try nitrogen or argon instead of air for arc spraying, this would reduce oxidation, but not eliminate it unless you spray in an inert chamber. I don't really see the point, unless its purely an academic study as it bears no relation to the real world.

3 months testing in air, that possible equates to less than 1% of the potential coating life. I think to be useful the testing period needs to be extended greatly.

A fair amount of oxides are produced during arc spraying, though with zinc most comes of as zinc oxide fume, but I'm sure some is included in the coating.

Possibly Related Threads…
Thread Author Replies Views Last Post
  Craking problem in Al2O3+ TiO2 plasma coating Hector Monjardin 4 2,896 09-22-2016, 01:33 PM
Last Post: Hector Monjardin
  Zinc arc spray vs Zinc-rich silicate or epoxy paint KeDuan 1 2,197 04-23-2016, 06:05 AM
Last Post: Stephen Booth
  Fused coating problem sprayloud 8 5,036 01-22-2016, 10:30 PM
Last Post: KevinS
  Coating delamination problem texnicar 13 7,719 07-07-2015, 10:37 PM
Last Post: Johnny_Blaze
  Metco 450 coating surface problem Yaakov 2 4,557 05-06-2015, 01:54 PM
Last Post: loriolo
  The coating problem of screw in exhaust plastic extrusion granulator 657666143 2 3,259 11-19-2013, 07:42 AM
Last Post: 657666143
  coating on zinc bath pot walls shantanu 2 2,707 07-03-2013, 10:47 AM
Last Post: plzc126330
  Blistering problem in Chromium Carbide Coating -- Reg sreenuvundela 4 5,461 04-28-2013, 07:14 PM
Last Post: shantanu
  brass coating over zinc part reg., prabu 2 3,473 11-08-2011, 09:40 AM
Last Post: xeviarjekel
  about corrosion against zinc molten denghans 3 4,251 05-31-2011, 12:30 PM
Last Post: denghans
  W121 coating - Parameter Problem ir_minja 1 4,349 02-21-2011, 07:25 PM
Last Post: Gordon
  zinc Metco 10E sebastiangt 5 5,470 07-15-2010, 09:23 PM
Last Post: sebastiangt
  Tungsten carbide coating problem ycwbycwb 8 13,292 05-20-2008, 01:42 PM
Last Post: ycwbycwb
  WC-Co16 coating problem enquiry howied 8 11,656 07-18-2007, 08:57 PM
Last Post: Gordon

Users browsing this thread: 1 Guest(s)

Surface Engineering Forum Sponsor - Alphatek Hyperformance Coatings Ltd