Thursday, April 15, 2021, 18:24

Tantalum samples were loaded in a tantalum testing tube and installed in the EVAP2 to heat under vacuum for 3 days at 2000 degC (~500A, 4kW).

The temperature is measured with the Omega pyrometer (slope 0.98)

Some of the samples are in contact with graphite and enclosed with Ta caps, the other samples are not in contact with carbon.

The testing tube is wrapped with 3 Ta heat shields and is not TaC coated.

Thursday, April 15, 2021, 18:31

IGP1 = 4.5e-7 Torr

Good vacuum = 3e-2 Torr

Bad vacuum = 5e-2Torr

The TGHT will be ramped to 500A at 5A/min

Thursday, April 15, 2021, 20:00

Finished ramping

TGHT = 502 A, 8.22 V, Omega 2012 degC

Sunday, April 18, 2021, 20:38

After 3 days at ~2000 degC, TGHT was ramped at -2A/min to 0A