Bonding Tungsten and/or Iridium?

This forum is for specialized infomation important to the construction and safe operation of the high voltage electrical supplies and related circuitry needed for fusor operation.

Re: Bonding Tungsten and/or Iridium?

Postby Jerry Biehler » Wed Aug 30, 2017 8:59 am

Based off of what? When you pull the wire off does the wire break and leave material behind? Is it slightly embedded in the base material?
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Re: Bonding Tungsten and/or Iridium?

Postby ian_krase » Wed Aug 30, 2017 10:33 am

Yes and yes.
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Re: Bonding Tungsten and/or Iridium?

Postby Bruce Meagher » Wed Aug 30, 2017 8:44 pm


As Jerry and others have mentioned, ideally you want a transformer whose secondary has one or two turns to make proper spot welds. You’re after gobs of current for a very short interval (with pressure). Check out the attached two documents for a great primer on the subject. Of course you can weld two pieces together by pumping power in like you are doing, but a proper spot weld requires lots of current for a short duration to create an ideal nugget. Dissimilar metals and different thickness material require special attention to the electrode design to make the nugget form properly.

Last year I was struggling with spot welding a tungsten filament to an NPS support for a vacuum tube. George clued me in to the proper surface preparation requirements for the material being welded so don't forgot about that aspect too.


Resistance welding.pdf
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Fundamentals of Resistance Welding.pdf
(1.38 MiB) Downloaded 20 times
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