GTA in helium shield, 100kfps(Under construction)

20120103He100A,150A & Ar 150A, 100kfps

nHe100A	nHe150A	nHe150A	aHe150A	aHe150A	nAr150A	aAr150A

High-speed video movies at 100kfps for arc ignition stage of Gas Tungsten Arc welding.
There are many debris on the used cathode. They are selectivley ionized in the first stage of igniton by high-frequency ignitor.
Active flux on the surface of stainless steel is also selected for target of atoms.

201202241315_08he_100kfps

201202241431_09he_100kfps

100kfps	1kfps	1k_dif	1k_max	20kfps	20kdif	20kmax
201202241451_10He200A, 100kfps

We need video rate more than 100kfps to watch precise cleaning action on cathode surface. The cathode surface is fully coverd by oxcides. And, there are a lot of debris about 10 mm apart from the cathode top. They are crystal of thoria, those were melted by heat during former arc welding process.
Video rate of 1kfps is too short to watch cleaning action of the cathode surface. "1k_dif" is a processed image of 100 frames to shorten the video rate. They shoe the subtracted number fro maximum value to minimum value for each pixcells.
"1k_max" is a processed image of 100 frames to pick-up the maximum values for each pixels.