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Want to weld up some titanium tubing for an older motorcycle exhaust header. I would like the material to be titanium. I'm considering doing this myself in order to learn. I understand that getting to a baseline to weld titanium could become expensive.

I'm interested in understanding the following components.

  1. How much amperage would be required in order to support titanium welding?

  2. Are there general welder types that are more effective at accomplishing the task than others?

  3. Is welding titanium with some sort of inert gas recommended or can the surface be exposed to oxygen during the welding process?

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    I'm pretty sure you'd have to use a TIG welder with 100% argon and usually when you do work like that you want to have the shielding gas cover the top and bottom of the weld. – Ben Mar 1 '16 at 21:56
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  1. Amperage will depend on thickness of the material. I can't give you an exact number, but any small TIG machine should do unless you're welding turbo stuff with thick flanges (like 3/8 or 1/2 inch).
  2. You need a TIG welder for sure. With a TIG you can control exactly how much heat is going into the weld which is even more critical than typical steel welding.
  3. Welding titanium is no different in this respect. It still needs an inert gas to shield from oxygen. All titanium tubing I've welded also had gas flowing slowly through the inside of the tube via a separate tank so both sides of the weld are shielded.

I recommend you find someone or a school that is willing to show you the process before you begin on your own. There's nothing wrong with jumping head-first into learning something, but DANG titanium is expensive to play with. Start with mild steel if you've never welded before.

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  • stainless is fairly cheap as well and is much the same process. – Ben Mar 3 '16 at 1:34
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You can't make an adequate weld. Titanium is a poor choice for exhaust pipe. At exhaust temperatures it will oxidize and nitride and become brittle. It could be welded with a TIG machine , Ar gas , A trailing shield must be used on the torch, the inside of the pipe must be purged with Ar with no air contamination. If properly welded the color will be silver, traces of light gold color are acceptable - dark gold or any blue shows contamination and a brittle weld.

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  • If titanium is such a poor choice for exhaust pipes, then why is it used in high-end exhaust applications? One factor of course is that it is lighter compared to steel, but if it really becomes that brittle it would not be used at all. – MadMarky Jun 8 '18 at 8:48
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    It is used for tail pipes ( below about 800 F ), not header pipes ( up to 1400 F). ASME code does not list allowable stress for temperature above 700F because the strength gets very low. And it can stress corrosion crack at 600 F if contaminated with chloride like road salts. I am biased having done much failure analysis and seen so much failed titanium, Mostly it fails by hydriding in the petrochemical business. – blacksmith37 Jun 8 '18 at 13:29

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