12.3

Saturday, November 23, 2019, 14:00

Container coated with TaC and wrapped with 3 Ta heat shields.

Desired temperature= 1900 C, Omega Slope set = 0.990, Auto TGHT at 0.2A/min to reach 400A, TGHT will be tapped up accordingly to reach desired Temp.

TBHT will be set fixed at 230 A (max). 

Good vac at 3.00e -5 Torr

Bad vac at 5.00e-5 Torr

Chamber pump down was started on Friday November 22; however.

No leaks were observed when turning water lines on.

IGP1= 4.6e-07 Torr

 Saturday, November 23, 2019, 15:30

autoramp at 0.5A /min up to 50A for both TGHT and TBHT and maintained for 1 hour.

Saturday, November 23, 2019, 16:15

IGP1= 1.1e-06 Torr

Auto Ramp to 450 A on THGT and 230A on TBHT at 0.5A/min

Saturday, November 23, 2019, 23:44

IGP1= 5.2e-06 Torr

TGHT = 248A, 2.9V  TBHT= 233A 2.9V

Increased ramp step to 1A/min to 620 A

Sunday, November 24, 2019, 00:14

IGP1=1.9e-06 Torr

TGHT = 274.3, 3.3V   TBHT= 233A, 2.9V

Sunday, November 24, 2019, 07:33

IGP1=3.2e-06 Torr

OMEGA= 1490C

TGHT = 619 A, 9.1V   TBHT=233A, 2.9V

Continue ramping THGT at 1A/min to 700 A

Sunday, November 24, 2019, 10:05

IGP1= 2.1 e-05 Torr

OMEGA= 1676 C

TGHT= 700A, 10.6V   TBHT= 233A, 2.0V

Start autoramp to 780A as per regression in attachment

Sunday, November 24, 2019, 13:22

Autoramp to 795A  for TGHT

Sunday, November 24, 2019, 21:16

OMEGA= 1854 C

TGHT= 789.6A, 12.27V  TBHT= 233.A, 2.9V

IGP1= 2.0e-05

Will allow pressure to stabilize lower.

Sunday, November 24, 2019, 22:16

TGHTT= 789.6A, 12.3V TBHT=233.3A, 2.9V

OMEGA=1855C

IGP1 = 6.9e-06Torr

Start cooling TGHT at 2A/min and TBHT at 1A/min