Monday, September 10, 2018, 15:09

Container is coated with TaC and wrapped with Ta heat-shield ( 3 layers)

Desired temp = 1900 C (expected TGHT ~445A/7.5V), TBHT will be set fixed at 230A (max).

Good vac at 3.00-5 Torr

Bad vac at 5.0e-5 Torr.

Chamber is currently being pumped down

 Tuesday, September 11, 2018, 09:27

Pressure at IGP1 8.61e-7 Torr. 

Auto ramping TGHT at 1A/min to reach 400A, and TBHT at 1A/min to reach 230A.

 Tuesday, September 11, 2018, 12:05

Pressure increased to 6.9e-e5 Torr and auto-ramp reduced the current:

TGHT from 94.6 A to 84.86 A

TBHT from 87.8 A to 78.87 A

(see figure EVAP2-_01)

EPICS automatically started ramping up TBHT and TGHT current when the pressure was between the good limit.

 Tuesday, September 11, 2018, 14:29

TBHT current reached ~230 A and EPICS stopped inputting current automatically. 

TBHT current reading on:

EPICS 232.8 A

Power supply: 235 A

 Tuesday, September 11, 2018, 16:53

TGHT reached 400 A, EPICS stopped auto-ramping automatically. (Fig. Heater-ramp and Plot_400A-230A)

Temperature read by OMEGA 1837 C (Fig. Tempeature-at-400A)

 Tuesday, September 11, 2018, 17:40

TGHT current was increased manually to 419 A (power supply current 422 A, EPICS plot 421.6 A) in steps of ~5A/2min

The temperature after ~30 min of being at 419 A is 1898 C.

The container will stay 5 hours at 1898 C 

Wednesday, September 12, 2018, 09:05 

EVAP2 remained at max setpoints for 5hrs

Auto-cool was set to 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

The automatic ramp decreased the TBHT current to 0A, but not so for TGHT, 

TGHT only reduced to 22 A, the TGHT was manually tapped to 0A

 Wednesday, September 12, 2018, 18:30

Process completed (fig. TaC-coating). 

Chamber was vented.