Monday, September 24, 2012, 15:12, Nikita Bernier, TaC, , , Done, Sintering Ta foil with TaC coating
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Monday, September 24, 2012, 18:09, Nikita Bernier, TaC, , , Done, Sintering Ta foil with TaC coating
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Wednesday, September 26, 2012, 15:06, Nikita Bernier, TaC, , , Done, Sintering Ta foil with TaC coating
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Nikita Bernier wrote: |
Monday, September 24, 2012, 15:01
The target boat with TaC coating is being used again. The inside of the boat is covered with a 0.002 inches thick Ta foil with TaC coating, wrapped with a 0.002 inches thick Ta foil.
Chamber was pumped down to 6e-6 Torr before the Heat Shield cooling water valve was opened. A small vacuum bump was detected (See attachment #1). It is not clear if it was caused by a water leak or not.
After consulting with Peter, I will wait for the vacuum to be below e-07 Torr before turning the target heater on.
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Monday, September 24, 2012, 18:02
The vacuum was stable until 1e-06 Torr. The target heater was turned on and tapped up to 60 A (0.8 V).
Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 800-850 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).
Tuesday, September 25, 2012, 15:11
Sintering process is going smoothly. See Attachment 1. The auto-ramping was increased to 1 A/min up to 800-850 A.
Tuesday, September 25, 2012, 16:11
And the voltage limit was increased to 18 V ! See Attachment 2.
Tuesday, September 25, 2012, 19:13
Around 806 A (readback), voltage increased more quickly than the current. It seems like resistance is building up. After reaching 836 A (readback), the current was tapped down to 800 A (readback)/ 816 A (setting) in an effort to save the Ta boat. See Attachment 3. The current will stay at 800 A for ~4 hours before ramping down.
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