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OrionWelders.com
ch.7
removed via glass brush or clean rag.
Yellow gold physical properties and composition (one possible):
58-75% gold, 12-27% silver, 9-15% copper and some zinc
White Gold: White gold is also a relatively simple metal to work with. ere are two main types of
white golds – palladium-white gold and nickel-white gold.
Palladium – white gold composition (one possible):
58.5% gold, 10% palladium, 28.5% silver, 2.5% (copper, nickel, zinc)
Nickel – white gold composition 14k (one possible):
58.5% gold, 25.8 % copper, 15.3% nickel, 0.4% zinc
Gold color can be changed with the following alloying (show alloy chart by composition and color)
Note the zinc content of white gold. High zinc content can lead to weld defects like porosity, etc.
as the zinc boils out of the weld joint. Please see the previous discussion on overcoming porosity.
In short, welding over the location with porosity again will help remove the porosity. A fresh, sharp
electrode will help with this process. Sometimes adding pure laser wire will also help in removing
porosity.
In general, gold welds easily. Here are some tips when working with gold:
1. Typically a sharp electrode is preferred when welding gold.
2. Gold can easily accept small or large weld spots
3. It is often typical that gold will look black surrounding the weld location. is black layer is
easily removed with steam cleaning, clean rag, or a small glass brush.
4. Gold can easily be added to almost any other metal.
5. Very interesting welding combinations are possible.
Platinum (Pt)
Platinum (Pt) has a melting temperature that is similar to stainless steel, but a density that is 3
times higher. In addition, the specific heat of (Pt) is lower by a factor of 4 than stainless steel. is
means that it takes less energy to raise the temperature of (Pt) to its melting temperature. e
end result is that (Pt) is a little more difficult than stainless steel to weld but very similar in overall
behavior.
One important consideration when welding (Pt) is its high boiling temperature (3827 deg C)
relative to tungsten’s melting temperature (3410 deg C). What this means: if the tungsten
electrode is contaminated with (Pt) metal the (Pt) metal may superheat and start to boil right on
the electrode. is boiling of the (Pt) will in turn melt the tungsten electrode causing it to lose its
sharp shape.
Palladium (Pd)
Palladium (Pd) is a white lustrous metal that is typically a much lower cost than platinum.
Palladium is also much lighter, having a density ½ that of platinum. It would seem that (Pd) is the
perfect metal. Unfortunately, (Pd) is generally difficult to work with and is somewhat difficult to
weld in a jewelry setting. is is mainly due to palladium cracking during the welding process.
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