Wednesday, March 28, 2018, 11:35
D-shaped discs were cut from cast 2, the same as the last sample of 1stepUCx [see elog i.d. 197]
A 13mm punch was used to punch out discs from pre-cut strips using the old method.
The target consists of 195 discs with 8.1cm in length - all single discs, no packs.
195 x UO2/C discs = 19.79g
Graphite insert is placed inside a target boat with both endcaps on.
Boat previously coated with TaC and sintered.
Ta-target boat is wrapped with 3-layers of heat shield and installed in evap1 yesterday afternoon.
Chamber pumped down overnight.
Wednesday, March 28, 2018, 13:33
IGP1 = 4.03e-7 Torr
Tapped up TGHT manually to 80A, 0.83V - waited 50min, vacuum started to drop/stabilize.
Continued to tap up manually to 430A, 4.22V
Started out slow with a rate of ~10A/5min, and slowly increased to a rate of ~10A/min as vacuum stabilized, slowing down again when reaching carbonization outgassing.
Auto ramp at 0.2A/min from 430A-520A.
Thursday, March 29, 2018, 10:04
Reached 520A around 2am.
TGHT = 520A, 5.13V
IGP1 = 1.74e-6 Torr
Initiated auto-cool this morning at a rate of 1.0A/min.
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