Friday, March 07, 2014, 11:41
The target container end-caps were sintered previously, but did not fully complete the sintering process [See elog entry # 119 EVAP2]
The caps are inserted in the target boat wrapped in graphite foils with 3 x Ta-heat shields.
The chamber was pumped down overnight.
IGP1 = 2e-7 Torr
HS cooling water valves were opened; no leaks detected.
TGHT was stepped up to 35A, voltage max set at 9.05V. TBHT currently at 0A.
Friday, March 07, 2014, 11:52
Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.5A/min and max setpoint to 500A.
Will ramp to 500A due to last failed round of end caps breaking with 3-ta heat shields at 580A.
Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.
Friday, March 07, 2014, 13:21
IGP1 = 8e-7 Torr.
TGHT = 72A
Vacuum stable; therefore, increasing ramping rate up to 1.0A/min
Friday, March 07, 2014, 14:20
IGP1 = 9.8e-7 Torr
TGHT = 130A
Vacuum stable; therefore, increasing ramping rate up to 2.0A/min
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