| Aaron Schmidt wrote: |
|
Wednesday, August 07, 2024, 15:36: Roughing. Had initially been roughed & TP started w/ Marla CS, however it timed out. Restarting.
Wednesday, August 07, 2024, 15:37: TP on.
Wednesday, August 07, 2024, 15:46: Tripped at 4 KRPM. Restarted. Up to 5 KRPM.
Failed to start.
Thursday, August 08, 2024, 10:00: TP started.
Thursday, August 08, 2024, 10:12: TP Tripped but nearly spun up. Reset & Restarted. TP Green / on.
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Thursday, August 08, 2024, 10:43
A cartridge was filled with graphite foils and loaded in an uncoated tantalum tube. The tube was wrapped with four Ta-sheets. A Ta-foil was placed in the tube's right end for measuring the temperature.
Green graphite target characteristics
| Number of discs |
822 |
| Mass of discs |
11.74 g |
| Mass of loaded cartridge with normal cap and hole-cap |
31.1290 g |
| Mass of tube loaded, w/shields and tantalum cap |
250 g |
Note: A cartridge loaded with graphite foils has not been conditioned before. Thus, there is no reference on what current to use to reach 2000 °C.
The conditioning of a graphite composite target will be used as a reference, but note that the graphite foils are not expected to outgas as the composites since the foils do not contain binders and plasticizers.
Reference: Elog 636 Graphite inside insert Experiment 2 (regular formulation discs)
Initial ramps used in elog 636:
Currently waiting for vacuum to reduce to IGP1= 8.2e-07
Thursday, August 08, 2024, 11:23
Slope: 0.98 (same as slope used for tantalum targets since temperature is measured on Ta foil)
Friday, August 09, 2024, 08:50
Good vacuum 3e-5 Torr
Bad vacuum 5e-5 Torr
Initial IGP1 = 5.06E-7 Torr
Starting ramp at 1A/min to 200 A
Friday, August 09, 2024, 09:40 Pressure started to rise, but temperature is not within pyrometer range yet. Current 42 A, Voltage 0.5 V
Friday, August 09, 2024, 10:46 Pressure started to reduce (peak 1.4e-5 Torr). Temperature is not within pyrometer range yet Current 100 A, Voltage 1.3 V
Friday, August 09, 2024, 11:28 Temperature started to be detected, but not stable enough. Current 135 A, Voltage 1.9 V
Friday, August 09, 2024, 12:54 Temperature 1129 °C, current 196 A, voltage 3 V.
Friday, August 09, 2024, 12:56
Next ramp 0.5A/min while taking temperature readings periodically until 250A
Friday, August 09, 2024, 14:45
IGP1 = 1.0e-6 Torr
Next ramp 1A/min to 480 A aiming at 2000 °C
Friday, August 09, 2024, 17:13
IGP1 = 1.9e-6 Torr, Current 327A, Voltage 5.3V
Ramp changed to 2A/min to 480 A aiming at 2000 °C
Coolded down after 4 hours at ~2000°C
at -2A/min |