I'm working with Pt 95 at the moment and seem to be getting a
heap of air pockets forming each time I try welding or melting the
If the alloy you are using is a cobalt platinum, then this is just
the nature of the beast. It tends to more porosity in torch welding.
Be sure your torch flame is close to neutral, not strongly
oxidizing. You don’t want a reducing flame either, but close to
neutral. That may help. And take care not to overheat too much.
One solution to joins, is instead of welding, use the plumb platinum
solders. They’re a perfect color match, work well with cobalt
platinums, and solve the problem of porosity in seams. If you’ve
got a laser welder, use argon shielding.