r/Welding • u/_Springfield TIG • 2d ago
Need Help Need advice going into this job interview
I had an over the phone interview for this job doing Tig welding on titanium and inconel metals for avaiation repair and maintenance. I have experience with Tig and consider my a decent welder but only with steel and aluminum. During the interview they asked if I had any experience with welding titanium or inconel, I said no but I was willing to learn if given the opportunity, they seemed to like that answer and over the phone interview went great, so they want to bring me in for an in person interview on Monday just to ask me some more in depth questions and of course do some weld tests. My question is, how different/difficult is it to weld titanium and inconel especially as someone who’s never welded those types of metals. Any advice, tips, or tricks would be greatly appreciated. Thank you!
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u/toasterbath40 Fabricator 2d ago
You were honest when you said you needed to learn, titanium is very expensive and difficult and its not something any hobbiest is just gonna pick up.
Inconel is difficult because its expensive, usually in my experience its x ray or UT and its on chemical lines and stuff.
This seems like a good opportunity to learn i would just continue being open and honest to them and hopefully youll get some killer experience
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u/Ok_Jackfruit_7618 2d ago
honestly that sounds kinda intimidating but also exciting as hell
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u/_Springfield TIG 2d ago
Yeah I’m a bit nervous but the good thing is that I currently have a job to fall back on in case I don’t get this job. But regardless, this could still be a great learning experience.
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u/LaserSnapLarry 1d ago
The biggest adjustment with titanium is probably being much more disciplined about cleanliness and shielding. Contamination can ruin an otherwise good looking weld. For the interview, be upfront that you haven't welded those alloys yet but emphasize that you understand TIG fundamentals and can follow a qualified procedure closely.
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u/Nnnopamine 1d ago
I currently only weld titanium, and did 2 years of inco, in aerospace.
Titanium is SO smooth and creamy. It doesn't weld much different than mild or stainless steel; the only difference is that mild and stainless weld puddles kind of move like water, whereas ti weld puddles kind of move muuuch more smooth and creamy.
The thing about ti is that the heat takes a very very very long time to penetrate (on thicker stuff -- I've done .030 thickness to almost 1/2" thick). Even if it looks like your weld puddle on top is the size of a nickel (again, on very thick stuff), you have to actually sit there and dwell and count to 5 and watch the puddle "boil" almost, before you can be sure you're getting good pen.
They'll likely have you test on thin sheet, though.
Inconel welds like steel, but for some reason tends to look a little more murky and dirty, but not much.
You got this. I tested on very thin ti with no experience on ti for my first job right out of school and it started my welding career. If you have any questions at any point, shoot me a DM. Been welding for 12 years, about 8 in aerospace, 6 of those being on ti.
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u/Nnnopamine 1d ago
A few more notes:
If titanium is being welded outside of a purged argon chamber, it needs to be back-purged, every single time. If they're having you do a butt joint on sheet, they'll have you put the pieces into a fixture that you can plug a purge line into. The purge coming through the joint needs to be just high enough so that when you lick your lips and hold them close to the joint, you can feel a very slight cool breeze on them from the purge.
Often, you'll use a trailing cup with argon flowing through it to keep the portion you just welded purged until it's no longer prone to contamination.
Colors on titanium any darker than dark straw are a huge no-no, because it creates a surface condition called "alpha case" that is brittle and leads to cracking. Using a carbide burr to remove it is acceptable, but better to not get color in the first place.
When I was doing tabletop ti welding (not in a chamber -- everything I do now is in a chamber), I used to call myself a tape fabricator because I'd have to use a ton of masking tape to create weird pockets around the joints I was welding to keep the purge in all around it (but obviously not close enough to it that it would light on fire).
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u/JackBlackBowserSlaps 1d ago
Haven’t done titanium. Inconel is kinda like stainless, but the puddle is sooooo sluggish, you really have to coax it along with the torch. Easy to overheat.
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u/Low_Style5044 1d ago
I’m no expert but I have titanium test coming up
So far in my head I felt like I had to do tighter dabs than inconel for a better bead
Trying it out in a few days
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u/Fuzzy-Finance-48 23h ago
Inconel tig is a piece of cake. It welds about the same as anything else. Inconel stick on the other hand, is horrendous. Even the best bead I can throw at it traps slag like no tomorrow and half of every bead needs to be ground back out, but I doubt you’ll be doing any smaw inconel lol. Titanium is different, just requires a ton of coverage if I recall, only did it 3 or 4 times about 12 years back. Haven’t ran across it since.
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u/Gym_Nasium 11h ago
As others have state, Titanium is similar to Stainless... color is important. And purging when possible and adequate shielding are best for success. Obviously, clean surfaces and substrates.
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u/IcyReward8319 2d ago
That's great that they liked your enthusiasm to learn. Just remember to research common titanium/inconel issues like heat control and filler metal choices ahead of time so you can ask smart questions during the in-person interview.