Friday, March 13, 2020, 13:52
Total number of foils: 493
Total length packed 17.4 cm
container has 3 Ta heat shields.
No endcaps inserted to facilitate out-gassing
Two TaC coated Ta wire springs inserted at both ends.
Initially to ramp TGHT and TBHT to 50A at 1A/min
Then heat manually to OMEGA ~1400 C , ramping TGHT manually and automatically to reach 530A A (Omega slope set = 0.990)
Then temperature = 1800 (C using slope 1.08 at after 1700C manually and automatically ramp to 700A then TGHT will be tapped up accordingly to reach desired Temp).
TBHT will be set fixed at 230 A (max). TBHT heated manually and automatically to max.
Good vac at 3.00 e -5 Torr
Bad vac at 5.00 e-5 Torr
Evaluation discs not included because no space.
Total Green disc mass measured = 58.78 g
Friday, March 13, 2020, 14:22
Container loaded and pressuring down started without any pump issues.
Friday, March 13, 2020, 23:26
IGP1= 9.1e-07 Torr
Start auto tap at .25A/min to 50A on both TBHT and TGHT
Saturday, March 14, 2020, 07:09
IGP1=6.9e-6 Torr
TGHT = 49.1 A, 0.58V
TBHT = 49.2A, .49V
Continue ramp to 80 A on both heaters at .0.25A/min (good vacuum 3.0 e-04 Torr, bad vaccum 5.0 e-04 Torr
Saturday, March 14, 2020, 08:22
IGP1=6.8 e-05 Torr
Pressure spike TGHT =63.7 A, 0.77 V; TBHT = 60.0 A , 0.62 V
Aborted ramp alow to stabilize (Tapped TBHT to 63.8 A
Saturday, March 14, 2020, 12:16
IGP1= 8.1e-05 Torr
start autoramp at 0.25A/min
Saturday, March 14, 2020, 17:47
IGP1= 2.9e-05 Torr
TGHT= 78.4A, 1.0 V
TBHT = 79.4A, .88 V
manual and automatic tap up to 740A TGHT and 230A TBHT then tap manually to 1800 C (mostly at .075 A/min and increasing to 1A /min as pressure stabilizes)
Sunday, March 15, 2020, 22:40
OMEGA = 1711 C
TGHT = 784,6 A, 12.9V (readback)
TBHT = 232 A, 3.5 V
Tap TGHT to 800 A readback set to 815A
Sunday, March 15, 2020, 23:20
OMEGA =1801 C
TGHT = 799.2 A, 13.3 V, TBHT = 232.9, 3.6V
Start gradual tap-down as temperature rising (1810 C at end of this note)
Sunday, March 15, 2020, 23:49
OMEGAA = 1818 C
TGHT = 769.9A, 12.6 V; TBHT = 232.9 A, 3.6 V
Temperature dropping tapped back up to 799 A on TGHT read back (set to 815 A)
Monday, March 16, 2020, 04:10
OMEGA = 1395 C (not reliable)
TGHT = 799.2 A, 13.2 V
TBHT = 232.9 A, 3.6 V
IGP1 = 2.2 e-06 Torr
Initiate cooling at -1.5 A/min on TGHT to 600A (at 600 A increase cooling rate to 3 A/min ; at 300 A increase cooling to 4 A/min and start TBHT cooling at 1 A/min; at `200 A on TGHT increase cooling to 4 A/min and TBHT 2 A/min)
Monday, March 16, 2020, 09:43
TGHT = 0 A , 0.02V
TBHT = 53,2 A, .56 V (increase cooling to 4 A/min)
IGP1= 1.12e-07 Torr
Monday, March 16, 2020, 10:37
IGP1= 9.5 e -8 Torr
TGHT and TBHT = 0A, 0V
Will unload container
Monday, March 16, 2020, 12:40
Ten discs removed for evaluation (6 from left side and 4 from right side)
two graphite discs placed at each end as well as two TaC coated and sintered end-caps
total length after sintering = 17.8 cm
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