Thursday, October 17, 2019, 12:00
Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)
Desired temperature= 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).
Evap 2 was pumped down on the previous night.
Good vacuum= 3.00 e-5 Torr
Bad vacuum = 5.00 e-5 Torr
Ramped TGHT and TBHT to 40A at 0.5A/min
Initial IGP1= 7.0 e-07 Torr
Thursday, October 17, 2019, 13:53
After pressure stabilization at 40A:
Autoramp TGHT and TBHT at 1A/min to 400A and 230A respectively.
Friday, October 18, 2019, 6:20
TGHT = 400A, 6.52V, TBHT= 233A, 4.1V
OMEGA = 1733C
Start autoramp to 430A on TGHT at 1A/min
Friday, October 18, 2019, 7:05
TGHT= 431A, 7.1V
TBHT= 233A, 4.1V
IGP1= 1.13e-06 Torr
OMEGA = 1828 C
Set autoramp to 465 at 1A/min
Friday, October 18, 2019, 11:13
TGHT = 465A, 7.8V, TBHT = 233A, 4.1V
OMEGA = 1865C
(Something is different with the heat dissipation on this target. Will leave at this current and start cooling at 1200 noon to avoid container strain)
Friday, October 18, 2019, 12:00
TGHT = 462.7A, 7.8V
TBHT= 233.4A, 4.1V
OMEGA = 1863C
IPG1= 1.02e-06 Torr
Commence cooling at -2A/min for TGHT and -1A/min for TBHT
Monday, October 21, 2019, 09:11
Pump down and dismount.
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