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Life calculation of various plating on steel, brass & copper at indoor condition

Hello,

Can somebody help me, I require a calculated (life at indoor condition) comparison chart of the various platings done on steel, copper & brass.

My requirement is like this:

For Example- The life of 10 micron zinc plated steel is equal to 12 micron Nickel plated steel in indoor condition.

Thanks in advance.

Bahadur singh
- Udaipur,raj. India
2000

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Hi Bahadur. I understand what you want and why it is important. But sorry, you are going to be out of luck on that. You simply can't compare a sacrificial coating like zinc plating to a barrier layer coating like nickel. The first one gradually dissolves away but offers protection until it is essentially gone, so it may have some projected life. The second coating does not dissolve away but only offers protection until it is scratched or nicked; then it accelerates the corrosion of the substrate because the substrate is sacrificial to it. Barrier layer plating is usually significantly thicker than sacrificial plating because porosity is not a serious issue for sacrificial coatings but renders barrier layer coatings worse than useless. 10 microns of zinc is a lot; 12 microns of nickel may be too little.

The NASF (www.nasf.org) offers an inexpensive set of "Quality Metal Finishing Guides" to the various types of plating which you may find helpful. Best of luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2000