Non-Chemical Am i doing more harm than good?

[jrmycooke]

Good day everyone. I was using a graphite crucible and wanted to see how conductive it was because I had just gotten off a job where I was doing a lot of carbon arcing ( copper coated graphite rod assisted with air for removing metal) . I put 22 grams of finger foils into the crucible and got the tig torch out. I adjusted the shield gas (100% argon) to 10 cfm so that I had enough coverage but not to much to disturb the foils. I ran the machine at 50 and and it melted the foils very nicely. The electrode on my torch is 2% thoriated tungsten and carries a temperature around 7,000 to 10,000 degrees. The arc itself is around 3 to 4,000 degrees. Is there a chance that I may be burning off values?........

 

[philddreamer]

I would recommend that you weigh the material before the melt, and then after the melt. this should give some clue.

Take care!

Phil

 

[publius]

I would say that gold's Boiling Point is 3129 K (2856°C or 5173°F) under standard temperature and pressure and your arc is approaching 10,000°F so you could be evaporating some of your gold.

Robert Jeffery, CWI

 

[jrmycooke]

The actual electrode is almost at the point of plasma, the final contact of the arc to the work is around three to four k.

 

[jrmycooke]

I didn't see the CWI, anything good out there lately? I'm on the b 31.1,3 side and the occasional d.1.1. I'm actually doing a little r and d to develop a weldment that has a ceramic matrix for corrosion apps. Don't have any real time data yet, but looking forward to seeing how it turns out.

 

[jrmycooke]

My message didn't post Phil, sometimes the simplest answer is the best answer. When I get back to the shop I will do as suggested.