What experience has anyone had laser welding Ti?
Some. You’ll need filler wire too, in order to get a fully filled
seam, on most types of work (just as with other metals). Reactive
metals Inc can sell you the wire, or, if you’re a masochist, you can
draw your own. But it’s really cheap to buy, and not so easy to
draw down to 30 guage…
Do all welders have a cover gas?
All of the modern ones have the connections and nozzles needed. The
actual tank and regulator, etc, is usually an optional add on. It’s
not needed for all jewelery metals, but is useful for some,
especially white golds. So whether a given laser has it available
depends on whether it’s owner has bought a tank and regulator, and
keeps it filled. Argon isn’t cheap, and the laser can go through a
surprising amount of it if you use it regularely (or at too high a
pressure).
Can Ti be fused to sterling, gold or other metals?
Yes. Gold works a bit better than silver. Silver takes a lot more
power to weld than does gold, so getting a clean weld can be tricky,
since at power levels needed to get the silver to melt, you’re
tending to blow holes in the Titanium. And the welds in silver can
tend to be brittle, which can be a problem if you can’t then anneal
the weld. But with some practice, you can do it. Using filler
wire made of silver solder, rather than sterling, helps a LOT.
This, by the way, isn’t unique to titanium. The same problems exist
in welding silver to other metals. high karat yellow golds too, also
can take fairly high power levels, and can be tricky to weld to
easier welding metals. Also, if the laser you’re using happens to
offer pulse shaping, you can avoid or lessen some of the problems
with weld cracking or brittle welds that some metals and combinations
thereof, can give you. The later models of the Rofin lasers (6000
series and later) offer this.
Can the seam be etched and electrically colored?
Yes. As with any laser welds, the crystal structure of the weld is
going to be different than that of the parent metal, and if your
filler wire is a different alloy, that too might affect the anoziding
properites. So there might be some difference in appearance. But
often, you can get a seamless look, with a perfect match. note that
once you weld TI to someting else, anodizing gets a lot trickier,
since the something else tends to act as a current sink, preventing
anodizing, at least in the area of the other metal. So then you have
to get into masking the other metal. But it can be done.
Hope this helps.
Peter