Cold forged anodized niobium

I work with wire, and am interested in starting to work with anodized
niobium. The only problem is that I do not know if I can cold-forge
the niobium. I really don’t want to get the wire and then find out
that if I hammer it, it will lose the colors.

Does anyone know?
Elizabeth Schechter
Silverhorn Designs
6400 Baltimore National Pike
Suite #170-A, #445
Baltimore, MD 21228

Hi Elizabeth, my experience is that forging/hammering after
anodizing results in dulling the color of the reactive metals, as the
hammer marks can wear through the oxide layer and expose the raw metal
to various degrees. But I don’t have a problem forging niobium or
titanium and then anodizing. Marty R.

Reynard Designs
Contemporary Jewellery & Wearable Art
Victoria, B.C.

Elizabeth, I have cold forged Niobium and it works well but takes a
good deal more work than many other metals BUT if it was colored it
will certianlly lose color and you would have to reanodize to get the
corret coler after you have prepared the surface as you would like.
Its not as daunting a task as it sounds and you can get some great
results. The people at Refractive Metals can really help but I don’t
have their info right now…let me know and I will get it or someone
out there knows.
Ron Kreml

Hi Elizabeth; Sounds like you’re new to working with niobium. I can’t
give you a lot of info here, but you can go to

and get more from them. They are a supplier for niobium
and other metals, and the tools and chemicals used to work with them.
I don’t know if there are sources for pre-colored niobium, but if
there are, you can only use cold joining techniques with such a
material, and you’ll need to be carefull handling it with steel
tools. Reactive Metals sells most of it’s niobium in a non-colored
state, and you color it when you choose. You need the anodizer and
solutions used to color niobium, the process is called “anodizing”.
As for cold forging, no problem, it virtually doesn’t work harden,
but the colors are vulnerable, since they are only microns in
thickness. Hope this helps. Contact Reactive Metals at 520-634-3434
for further infomation.

David L. Huffman

The anodized surface of niobium is extremely thin- the colors are
actually caused because the surface interferes with light. Forging
would have the effect of exposing surface that was not anodized, as
well as scratching and moving the surface around. Reactive Metals
makes a power supply for anodizing niobium, and unlike titanium, no
surface chemical etching is necessary for this process to occur.
Niobium has a great affinity for oxygen- it is this oxide surface
that produces the color- it is dependent on voltage- and so if you are
careful, you can reproduce the colors over and over.

My suggestion is to forge the un-anodized wire and then anodize it.
By stopping off areas and anoditing, removing the resist and anodizing
again at a lower voltage, you can froduce a range of color patterns.
Holly Yashe and other companies have been doing this for years on a
commercial level of production. The voltage range is from 3-150 or so
DC and the color range is repeated several times. The colors on
niobium are more vivid than titanium- and niobium is much easier to
form, forge, drill, and finish. Anodizing requires no special
solutions- just a conductive liquid- like salt water- will work. You
may find anodizing more fun than forging. Rick Hamilton

Gold and Platinumsmithing
Jewelry Photography

Yes, the color will go right away.

The colors of niobium are caused by a uniform outer layer of niobium
oxide. Any change in the surface changes the color.

When you work niobium the very last thing you do to the piece is
anodize (color) it.

John Flynn

Hi Elizabeth, Yes, it will lose the colour. I tried a snippet and
found it kept the colour on the edge but the flattened part of the
wire changed to a pinky grey from the teal colour I started with. You
would have to use plain niobium and anodize it after the forging to
get a consistent colour. Even when using the wire in wirewrap, the
colour shifts a bit in the portions that are bent the most, and tool
marks can easily reveal a grey spot. Additionally the stuff from Rio
is quite hard and a challenge to work with if you are used to softer
wire! The colours however are gorgeous - except for the yellow which
has a brassy colour to it and doesn’t look as expensive as it should!

      I really don't want to get the wire and then find out that if
I hammer it, it will lose the colors. Does anyone know? 

Niobium is softer than steel, and hammers, etc. So is the oxide, at
least in terms of being able to withstand much tool marking. while
you MIGHT be able to do some limited, very gentle forging with highly
polished tools, and maintain acceptable color, it’s a bit dicey. The
oxide layer is not particularly workable. You can bend it, but the
stretching it will get from working the wire will tend to fracture
that layer. Now, small cracks in the color probably won’t be noticed.
But much more than that, or actual scratches, dings, nicks, etc, from
actually working it? Those will show. The key is the question of
how much degredation in the color are you willing to accept?

Please also consider that actually recoloring the wire is simple to
do, if you’ve got a power supply capable of generating the required
voltages. Now, you can spend big money buying such a supply. but a
power supply capable of anodizing niobium is easy to make if you can
locate a variable transformer (also called a powerstat, or variac).
These are the things that also are used to vary the voltage in normal
electroplating supplies, so if you have such a thing, you can modify
it without too much dificulty, to allow you to also anodize niobium.

There are, of course, safety concerns to be addressed. Anodizing
niobium (or titanium or other reactive metals) used voltages in the
100 to 170 volt range, often as not, and these voltages are high
enough to be dangerous if you don’t handle them with respect. But
this is mostly common sense and a respect for the electricity, and not
doing things that expose you to the danger of shock. This is not hard
to do. The modifications needed to tap off higher voltages from a
normal electroplating supply are just a couple cheap diodes you can
get at radio shack or any other electronics supply firm. Cost is just
a few dollars for the simplest setup, which will still work just fine.
You can get fancier with the addition of filters, or voltmeters for
repeatability, but it’s not essential. And the chemicals involved are
completely safe. Set this arrangement up once, then you can buy
unanodized wire, work it to your heats content, and then color it as
you wish after you’ve worked it. A lot more versatile than buying
precolored wire.

It’s getting too close to my bedtime tonight to go into more detail,
but if people are interested, and don’t already know how to build or
modify a power supply to anodize reactive metals, I’d be happy to
write it down for anyone who needs. Like I said, it’s simple.

Peter Rowe

Since I can’t work the niobium after it’s colored, I obviously have
to work it before I color it. So here’s my next question…

What do I do with stones? Can the wire be anodized with stones
already incorporated?

Also, if I work with unanodized wire, is there such a thing as an
anodizing service? I don’t have a shop, I work out of the spare
bedroom. ;}

Feeling absolutely clueless…

Elizabeth Schechter
Silverhorn Designs
6400 Baltimore National Pike
Suite #170-A, #445
Baltimore, MD 21228

–I work with a lot of titanium, and some niobium. Ti will definately
lose its color of formed, ni less so, and it is softer, easier to
form. The best thing, in my opinion, is to form first, then anodize
after. --Noel