Thursday, September 11, 2014, 13:14
The target container end caps were coated with TaC spray and let dry.
The caps are inserted in the target boat wrapped in graphite foil with 3 x Ta-heat shields.
The chamber is currently pumping down.
Friday, September 12, 2014, 14:17
Chamber was pumped down overnight.
HS cooling water valves opened, no leaks detected.
IGP1 = 7.2e-7 Torr.
TGHT stepped up to 35A, TBHT at 0A.
Waited ~30min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min.
Will ramp TGHT to 580A with a max 10V.
Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.
Monday, September 15, 2014, 11:31
TGHT stopped at 500A due to not high enough voltage max.
Increased max voltage to 12V
Monday, September 15, 2014, 14:17
IGP1 = 6.3e-7 Torr
Increasing ramping rate to 1.0A/min
Tuesday, September 16, 2014, 09:04
TGHT reached 577A and finished auto-ramping, then proceeded to drop down to 560A overnight.
Increased max voltage to 13.05A and TGHT to 580A.
Tuesday, September 16, 2014, 13:52
TGHT reached 580A and sat there for ~5hrs.
IGP1 = 6.1e-7 Torr.
Initiating auto-cool at 2.0A/min.
Wednesday, September 17, 2014, 13:03
Vented in air.
Opened up....looked 'deceivingly' ok.
then i took a layer of Ta off....grrrr
the 1st layer of Ta was holding the boat together. as soon as that layer was taken off the target boat broke.
see attached photos.
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