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Alternatives to stainless steel wire or hot dip galvanising

Hi,

I am a sculptor from Singapore. I use only stainless steel wires in creating my art pieces. I have some pieces that are places in public spaces. As they are of 308 quality, they tarnish after some time. I am now given a project to place my work near a river. I am contemplating using stainless steel wire 316L or duplex. However, as the works are going to be permanent sculptures, the clients wanted to be really sure that they will be corrosion free. I am exploring into hot dip galvanising. But I also understand that in an urban or coastal area, they can only last 20 to 25 years. Also, the finishing effect will not be as good because my wires are intertwined / woven together to form into life sized human forms. the water-droplet effect at the points where the wires are intertwined are not so ideal.

I need to know what would be a good alternative to stainless steel wire or duplex in terms of being corrosion-free yet gives a good finishing.

Thank you,

Wendy Tan
- Singapore
2001

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Wendy,

Have you thought about powder coating? You can get any color you want as opposed to just a galvanized gray. The powder also applies in such a manner as to not result in the tear-dropping you describe. The coating life is similar to or in excess of that of galvanizing also.

Good luck,

Chris Comar
- Norfolk, VA, USA
2001

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2001

Hello Wendy!

You will notice an improvement if you use 316 or one of the duplex grades of stainless steel in preference to 308. The additional molybdenum in the 316 family aids in preventing pitting in seawater environments, and the duplex grades are well known for their resistance to chlorides. If 316 isn't good enough, then something like 20Cb-3, or even C-276 should work without the expense of say, titanium. Titanium would be magnificent overkill, and it would anodize beautifully, although you might want to coat an anodized piece with a clear lacquer.

I think you'll find the galvanized pieces, whether hot dipped as a sculpture or made from galvanized wire, to be very different. Remember that galvanizing works by having a zinc layer that corrodes preferentially to the steel underneath it, and it will turn to a dusty white layer as the zinc corrodes.

Finally, Carpenter Technology, a maker of stainless steels and nickel based alloys, offers a free but very nice 70 page collection of articles on "Corrosion Causes and Control". Check out their website at www.cartech.com and fill out the form if you want one.

Good luck!

Lee Gearhart
metallurgist - E. Aurora, New York

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If money is not an issue, how about titanium (or a Ti alloy) wire? Excellent corrosion resistance, high strength to weight ratio (about 2x that of 3XX stainless), can be polished.

Heck, it can be anodized to several vivid colors by any number of finishers here at finishing.com (search the list of worldlink listings on the site).

Dale Woika
Surface Conversion Sciences - Bellefonte, Pennsylvania, USA
2001