Tungsten degradation on Al, pic with in

[fun4now]

I'd hardly think that to say that it is not meant to be used on AC is correct
just going by the diamond ground tungsten guide book. not my words theirs.
i'll dig up the book and give ya word for word if you would like.

[fun4now]

2) CERIATED - CERIATED TUNGSTEN WAS INTRODUCED AS THE FIRST NON-RADIOACTIVE ALTERNATIVE TO THORIATED TUNGSTEN. 2% CERIATED TUNGSTEN IS HOW IT IS MOST COMMONLY OFFERED AND IT IS READILY AVAILABLE. IT IS KNOWN TO BE ESPECIALLY GOOD FOR DC WELDING WITH LOW AMPERAGE BECAUSE IT STARTS VERY EASILY AT LOW AMPS AND USUALLY REQUIRES ABOUT 10% LESS AMPS THAN THORIATED MATERIAL TO OPERATE. THUS IT IS MOST POPULAR MATERIAL USED FOR ORBITAL TUBE AND PIPE WELDING AND IS ALSO COMMONLY USED FOR WELDING VERY SMALL PARTS. CERIUM ALSO HAS THE HIGHEST MIGRATION RATE SO IT HAS THE BEST DELIVERY OF OXIDES TO THE TIP AT THE BEGINNING OF USE. THIS GIVES IT GOOD WELDING PROPERTIES AT THE BEGINNING BUT LATER YOU HAVE FEWER OXIDES TO SURROUND THE GRAINS SO YOU GET GRAIN GROWTH (I.E. GRAINS COMBINING) AND A SIGNIFICANTLY REDUCED MIGRATION RATE. HOWEVER, AT LOWER AMPERAGES IT SHOULD LAST LONGER THAN THORIATED TUNGSTEN. BECAUSE OF ITS PROPERTIES, IT WOULD GENERALLY BE GOOD FOR SHORT WELDING CYCLES AND ALSO WHERE A SPECIFIC NUMBER OF WELDS ARE CALLED FOR AND THEN THE ELECTRODE IS TO BE REPLACED. HIGHER AMPERAGE APPLICATIONS ARE BEST LEFT TO THORIATED OR LANTHANATED MATERIAL. THIS TUNGSTEN IS USED PRIMARILY FOR DC WELDING AND MAY SPLIT IF USED FOR AC WELDING.


i suppose its still considered a dule current option, just best suited for DC due to the possible problems with AC.
hope that covers my statement. not trying to start any thing, just explaining why i would post as i did.

[FusionKing]

Thanks for pointing that out Fun, I never read that. I've used 1/8" ceriated on ac aluminum at max on a 250 sync quite a bit tho and never saw splitting like that tho, just a nice ball. I always sharpened it and it just slowly burned back to size. Went from small ball on end of a point to larger the size of the tungsten.

[fun4now]

i suspect the inverter users would have more problems due to higher frequency's.
like i said many use it for AC, some have problems some don't. several here have reported splitting problems, wile some (like you ) have no problems. i just mentioned it as it could be a cause of his trouble. i am not trying to tell any one not to use it, just passing on the info i have on it.
i have tried it and think its a nice option, i just like 2% lanthanated better so thats what i use. to each his/her own.

[LAN]

Ceriated tungsten does not like to ball up cleanly, like pure tungsten, nor do you really want it to if you are using an inverter based welding machine. Using ceriated tungsten works great on AC, but one of the things that you will notice are nodules forming on the tungsten like you see in this picture after extended use.
This typically will happen after the tungsten begins to split a little bit at the end. After the tungsten splits a couple of times the tip of your tungsten now turns into 3-4 tips instead of the one that you prepared, and each of those tips begin to ball up due to the high amount of heat being put on such a small surface area. This is why these nodules form and it is typically seen after a lot of welding on the same tungsten without prep.

Some things that you may want to try

-A slightly higher balance. Setting your balance higher will minimize the amount of heat going into your tungsten, and reduce theses nodules from forming as readily. 65% EN on the balance if a bit lower than I like to have my machine set. I typically will weld with it around 70%-75% while using pure argon. This balance setting still provides plenty of cleaning on most materials. About the only time that I turn my balance lower than that is when I am welding something with an extremely thick oxide layer and need more cleaning.


-Prepare your tungsten with a small land on the end, like above, turn your balance down and form a small crown on the end of your tungsten (NOT A BALL, slightly round off the sharp corners on the tungsten). After you form this crown (NOT A BALL), turn your balance back to your operable range (70%-75% EN) and weld away. Typically it takes quite a bit of heat or consistent dipping of your tungsten to mess up that tip once it is prepped like this. It will not have the tendency to split and form these nodules that you are seeing once you prep the tungsten like this.

Good luck! Hopefully this helps out.

Brad H

[FusionKing]

Lan ...that was a most perfect explanation. I guess I MEANT crown in my explanation.
I will say tho ceriated has worked fine for me on AC for days on end at high amps on 10 hr shifts. It would be hard for me to see the original poster's choice of tungsten being his problem with the low amps he said he was running.

[boostinjdm]

I wonder about his electrode prep also. I like to just lay it on the edge of a sharp workbench, smack it with my wire pliers cuz they're always handy, and then regrind. I always make sure there isn't any cracks before I grind. this way has worked well for me.

[LAN]

... I like to just lay it on the edge of a sharp workbench, smack it with my wire pliers cuz they're always handy, and then regrind. I always make sure there isn't any cracks before I grind....

When preparing a tungsten, and you have a choice, NEVER, EVER, break it off. Who is to say that you are seeing the cracks that you are causing that run up the tungsten? Sure if you are in a pinch snap that baby off and prep it for welding (I've done that myself when I had no other way), but it is not the proper way of prepping a tungsten for quality fabricating applications.

Cracks can occur on a much smaller scale than you can see with your naked eye. When prepping a tungsten it is always better to cut the tungsten with a diamond wheel, then sharpen your angles on the tungsten that you will be using.

[Louis]

Lan, thank you very much. I will try all of that, and it makes sense too. I have not had any aluminum come across my bench yet since I made this post. I

I start with a fresh piece of tungsten, and if I do have to shorten it, it gets cut. I never knew why I cut it, just how I was taught.

I really do not want it to ball up, as that reduces how precise I can weld. I often weld 30-40 thou material, and that is SO thin its more difficult to weld with a balled tip as opposed to a nice sharp tip. Weld size is another matter. Engineers give you tolerances that look great on the computer screen, but when you try to lay a bead, real world, next to a machined hole thats 1/8" away, its tough with a ball.

Thanks again to everyone

[Louis]

Oh, and Lan, appleton is near Road America. You need to come to the ALMS race in August and say hi

[LAN]

Oh, and Lan, appleton is near Road America. You need to come to the ALMS race in August and say hi

I would love to see AMLS. I have been out to the track for track-days on my bike and to see the superbikes but never cars. That might be pretty interesting. Let me know where you're going to be and I'll come check it out.