Wednesday, August 23, 2017, 15:41
2 rounds of UO2/C were cast onto a graphite sheet in the fume hood and let dry.
For this round of samples, circles from cast 1 were used
Graphite powder used = 5.16g
A 14mm punch was used to punch out circles from a 16mm wide strip.
35 circles were packed into a graphite sample container.
graphite container [no endcap] = 3.37g
35 x UO2/C circles = 4.76g
graphite container+smpls = 8.13g
container+smpls+endcap = 10.08g
Graphite tube is placed inside a target boat.
Boat previously coated with TaC and sintered - 1st use of newly sintered boat.
Ta-target boat is wrapped with 3-layers of heat shield and installed in Evap1.
Chamber currently pumping down.
Friday, August 25, 2017, 09:59
IG1 = 3.45e-6 Torr.
Stepped up manually to 80A.
Vacuum stable.
IG1 = 3.0e-5 Torr.
Initiating auto-ramp.
Target boat will be ramped up to 520A at the rate of 0.1A/min.
Vacuum limit stop at 1.0e-4 Torr, backing off at 5.0e-4 Torr.
Monday, August 28, 2017, 08:09
IG1 = 6.3e-6 Torr
TGHT = 455A, 4.65V
Vacuum stable.
Increasing ramping rate to 0.2A/min.
Monday, August 28, 2017, 08:53
IG1 = 7.3e-6 Torr
TGHT = 465A, 4.75V
Vacuum stable.
Increasing ramping rate to 0.5A/min.
Monday, August 28, 2017, 13:17
IG1 = 1.32e-5 Torr
TGHT = 520A, 5.44V
Vacuum still fairly high and not dropping very fast indicating carbonization incomplete.
Increasing max setpoint to 530A and restarting auto-ramp.
Monday, August 28, 2017, 15:13
IG1 = 1.32e-5 Torr
TGHT = 530A, 5.58V
Vacuum still high, wavering up and down/ not dropping - carbonization remains incomplete.
Increasing max setpoint to 540A and restarting auto-ramp.
Tuesday, August 29, 2017, 09:28
IG1 = 3.72e-6 Torr
TGHT = 540A, 5.66V
Carbonization complete.
Initiating auto-cool at 2.0A/min
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