How to weld titanium shimstock 2

[EssieAutomation]

Looking for a little help on my application.

I need to create cylinders out of 0.003" thick titanium by wrapping the material around a form (solid cylinder with a groove cut out for weld tool) and then spot welding the overlapping ends.

The specs are: 0.003" thick titanium (MIL-T-9046, COMP CP-1, GRADE 4).

Currently, even our lowest setting on our smallest welder is easily burning holes through it. A little research has lead me to believe I need to use a small "dental welder" or "hobby welder" but would like the advice of the members here.

Anybody come across something like this? Anyone recomend a machine or process?

Steve

 

[EssieAutomation]

Also, in case someone wants to recommend a different joining process, I'll just add that the cylinders are being used in a high heat environment (exposed to flames).

 

[metengr]

Are you sure about your statement below?

I'll just add that the cylinders are being used in a high heat environment (exposed to flames)

Ti is normally not acceptable for use above 400 deg C because it will exhibit very poor oxidation resistance. Why was this material selected?

 

[unclesyd]

You need to look at the micro-tig and micro-plasma process for your application. Just remember that all other parameter needed for welding Ti still need to be followed. Depending on you particular application a glove box should be considered.

http://www.mpdwelding.com/microtig.htm

http://www.pro-fusiononline.com/products/microtig80.htm

 

[btrueblood]

metengr and syd posted what I was gonna say. Stars for both.

I did read something somewhere about spotwelding Niobium underwater, might be applicable to Ti as well...then again, might be a good way to electrocute somebody. Control of heat input via micro-tig and pulsed power supplies is going to help a bunch. In the end, getting the heat out of the Titanium is going to be the tricky part for such a thin gauge of material.

 

[EssieAutomation]

Thanks for the replies. As for material, there is a weight maximum and I couldn't source anything else that fit the bill. A dimensionally equivalent design in steel would not meet the requirements. Our prototypes, which are hemmed closed, look beat up but are still going strong.

Our welder has a micro-setup but it is slow and expensive. I was hoping for something a little easier/dirtier that we can pump out lots of these. I don't want to get tunnel vision, but I envisioned a mini spotwelder to perform the job, however I'm not a welding expert so the recommendations are appreciated.

 

[MiketheEngineer]

How about a rivet??

 

[unclesyd]

Check around with the micro-tig equipment as there are several approaches. We built a lot of very thin wall tubing equipment and used essentially a micro-tig orbital welding rig.

If you have good clean steady power from you welding power supply and an older welder. good eye sight, you might be able to use a resistance box to get the current down. this might not work for your material and thickness. I've seen such a rig work with 0.008" SS, much easier to weld than Ti.

I would also contact Weld Logic concerning your production problem. They should be able to give you some very specific advice and they may have some surplus equipment.

http://www.weldlogic.com/index.html

 

[EdStainless]

I have used micro-plasma down to 0.006" Ti. By hand.
We did it in a glove box to minimize oxygen pick up.

If you don't need full welds in these then you could make a series of 1/2" long stitch welds quickly.

You need to have no oxygen present. You might want to play with spot welding inside an argon purged glove box.

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