Standard coating thickness for Electroplated Zinc

[gearman1234]

I wish to specify "Electroplated Zinc coating plus Yellow Dichromate" specification on the drawing. I was looking for a standard thickness spec for such a coating.

I researched the web and machinery's Handbook for this and it looks like ASTM B633 is the standard being followed.

IS there any standard industry specified thickness which is being followed by industry in North America in general?

The parts are shafts and brackets and hubs for a recerational vehcile and need to exhibit corrosion resiatance in a standard environment and give a good apperance at the same time

 

[Goahead]

There are some general recommendations based on the prevalent atmosphere in service, wether rural, marine or industrial, and depending on the number of years of service.
Such a table can be found in the ASM Metals Handbook, 8th edition, Vol.2, pg 423 Table 8.
It appears that an acceptable thickness of plating could be between 1.0 and 1.5 mils for an acceptable life in a moderate environment.
It is suggested to check if for the application it would not be better to select cadmium plating instead, as it has less tendency to tarnish. For close fitting moving parts cadmium is generally preferred to zinc.
Regards,

http://www.welding-advisers.com/

 

[CoryPad]

Just about any thickness between 1 and 15 [µ]m is used in industry. A very common thickness is 8 [µ]m.


Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[swall]

One of my former employers used to spec electrodeposited zinc this way:
.0005" min. for severe environments, .0003" for moderate environments and .0002" for mild environments. The salt spray requirements were 96hrs, 48hrs and 32hrs, respectively.

 

[gearman1234]

Thanks for the information provided by all.