Hannah Toy wrote:

Tuesday, October 18, 2022, 13:52 38 pieces of samples made of TiO2/C/PVP loaded into a target boat wrapped with 2 layers of Ta-heat shield. Samples will be heated to 1700, 1800, 1900, and 2000 C Some of the pieces will be removed after each target temperature  Target chamber has been pumping down and the current pressure reading is 6.62e-6 T  Tuesday, October 18, 2022, 14:12 TGHT will be autoramped to 250 A Good vacuum: 3e-5 Torr Bad vacuum: 5e-5 Torr Omega slope: 0.99 Initiate autoramp: 1 A/min

 Wednesday, October 19, 2022, 09:42

TGHT has reached to 250A/3.95V, Temp at ~1100 C.  (The archiver is currently not working; already contacted Control to look into it.)

Pressure reached below 4.9 e-7 Torr. 

Auto-ramp to 300 A at 2A/min.  Continue to monitor.

 Wednesday, October 19, 2022, 10:24

TGHT reached to 300 A/4.89V.  Temp at 1206 C. 

Pressure went up slightly and came down after the TGHT setpoint was reached, see attachment#1.

Continue to auto-ramp to 350A at 2A/min.

 Wednesday, October 19, 2022, 11:35

TGHT reached to 350A/5.8V.  Temp at 1360C.

Pressure reached above 1e-6 Torr and came down after TGHT reached the setpoint. 

Continue to auto-ramp to 400 A at 2A/min

 Wednesday, October 19, 2022, 11:57

TGHT reached to 400 A/6.89V.  Temp at 1485C.

Pressure went up to 3.3e-6 Torr and came down after TGHT reached the setpoint,  see attachment#2.

A temp vs current plot has been generated (see shared folder \Hannah\) - est TGHT 480A to reach 1700 (T1).

Auto-ramp to 420 at 1A/min.  Continue to monitor closely...

 Wednesday, October 19, 2022, 13:01

TGHT reached 420A/7.23V, Temp at 1520 C.

Continue auto-ramping to 440A at 1A/min.

 Wednesday, October 19, 2022, 13:42

TGHT reached 440A/7.65V.  Temp at 1572 C

Continue auto-ramping to 460A at 1A/min.

Wednesday, October 19, 2022, 14:10

TGHT reached to 460A/8.10 V.  Temp at 1628 C.

Tapping up TGHT to reach 1700 C

 Wednesday, October 19, 2022, 15:33

TGHT was tapped up to 474A, Temp reached to 1700 C since 14:30.

Pressure is slowing coming down, currently at 1.4 e-6 Torr.

Will hold at this target current for a few hours.

 Wednesday, October 19, 2022, 16:58

Temp went up slightly to 1713 C as the pressure is coming down. 

Lower TGHT to 468A/8.45V to maintain the temp at 1700 C.

 Wednesday, October 19, 2022, 19:55

Temp went up again to 1716 C, but this time the pressure also went up, see attachment#3.  Not sure why the target got hotter... the voltage seems normal and consistent. 

Lower TGHT to 462A/8.44V to maintain at 1700 C. 

Continue monitoring...

 Wednesday, October 19, 2022, 22:56

Temp went up another 10 C, to 1710 C, TGHT is holding at 462 A/8.48V.  Notice the TGHT current readback is fluctuating between 458A - 463 A. 

Initiated cooling.. 2A/min

 Friday, October 21, 2022, 08:55

 All the samples were taken out from the Evap on Thursday Oct 20.  We decided to do so because there was not enough sample in each batch for XRD analysis.  All the sample will be analyzed as treated at 1700 C. 

See attachement #$ for the overall TGHT/Vac plot.