Zirconiated Tungsten Questions

Date 08-05-2004 03:00

Hi.

I have always used pure tungsten for aluminium, but have been told that zirconiated tungsten provides better welds in that it handles more current and provides a cleaner weld. I tried it, but found that the electrode when it gets hot never really balls up, but forms a little finger that walks around at the tip of the electrode and offers poor control of the electrode. I am usings high freq start and running high frequency for the duration of the weld. I am using it in A.C. at about 150 amps for a 3/32 electrode. 15cfh argon shielding gas.

Any imput would be greatly appreciated.

Thanks.

By swnorris (****)

Date 08-05-2004 12:52

Hi fst951,

The AWS states, "This electrode performs well when used with alternating current as it retains a balled end during welding and has a high resistance to contamination." For AC welding use a blunt tip because the arc tends to wander around a pointed tip.

Maybe this link to an article from The Fabricator about choosing the tungsten electrode type will be of some assistance:

http://www2.thefabricator.com/Articles/Welding_Article.cfm?ID=527

Another link to an article in The Fabricator that may be of interest to you:

http://www2.thefabricator.com/Articles/Welding_Article.cfm?ID=56

By fst951

Date 08-05-2004 14:26

Hi.

Thanks for the info. If you look at my post in this same forum below this, I am recommended to use a tapered tip. What gives, does a different process work for different people? When you say a blunt tip, you recommend that I just flatten out a piece of zirconiated tungsten smooth with no taper?

Thanks.

By swnorris (****)

Date 08-05-2004 15:46

Hi fst951,

Blunt meaning obtuse or less pointed at the end of the electrode. A pointed electrode is generally used with DC current, and a rounded electrode is generally used with AC. With conventional AC current, better arc action is obtained when the electrode has a hemispherical shaped tip. For your application, the taper length should be about two times the electrode diameter, and the tip should be shaped to about .75 times the electrode diameter. Grinding the electrode to a point helps starting the arc when making short duration welds. A flat spot or tip diameter at the end of electrode works best and reduces erosion at the thin part of a point and reduces the concern that the tip may fall into the weld.

By fst951

Date 08-05-2004 16:46

Thanks for the article. I will grind a few different electrodes and see what happens.

Thanks

By fst951

Date 08-11-2004 04:23

Hi guy!

I was working again today with Zirconiated tunsten. I could get a 1/16" to ball up on billet material, but I could not for the life of me get 3/32" to ball up. It kept on wanting to split or blunt. We are talking about 150 amps A.C. setting 6 for more penetration and less cleaning.

Thanks for any advice.