Thursday, August 22, 2013, 17:31
1st attempt:
UO2/C green was prepared on Aug 14, 2013 (wed). The slurry was cast on a piece of glass coated with WD40.
The cast was let dry until Aug 26 (Mon) - couldn't peel off from the glass.
2nd attempt:
So, scrapped off cast, mixed with 30ml H20 in the WC jar, re-milled for 3 hrs, and cast/let dry over night - SAME SHIT! couldn't peel off! Don't understand why?!
3rd attempt:
scrapped off, added the additional compositions:
1g PEG400,1g Glycerol, 10g 7% PVA, 2ml n-butanol, 2ml methonal, 20ml DI H2O.
Re-milled for 3 hours, cast and let dry! Wahlaa... it works! (See attachment#1: pretty uranium pancake!)
However... During this process, some lost of uranium was resulted. The slurry was more viscous than normal. Some material was stuck to the WC jar wall and the balls.
Initial UO2 powder used = 50.14g (Inventory R-00835A UO2 + bottle = 795.56 before use)
Graphite powder used = 10g.
1st attempt dried UO2/C + organic mass = 55.75g
2nd attempt = didn't measure
3rd attempt + additional org mass = 44.5g (expecting to loss more uranium from the scraping/sticking to jar/balls)
The green was rolled up and wrapped in a piece of graphite sheet.
The Ta-target boat was wrapped with 3-Ta layers of heat shield and installed in Evap1 on Aug 22, 2013.
Chamber is currently being pumped down. IG1 @ 2.4e-4 Torr.
Target will be ramped up to 520A at the rate of 0.1A/min
Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr
Monday, August 26, 2013, 11:28
Chamber has been pumped down over the weekend. IG currently @ 5.2e-6 Torr, BP @ 38mTorr.
Stepped up TGHT to 30A/0.151V.
Monday, August 26, 2013, 12:28
TGHT has been at 30A for almost 50 min. Pressure has gone up but stabled at ~ 3.7e-5 Torr.
Initiated auto-ramping...
Monday, September 09, 2013, 15:35
The carbonization process has come to an end.
TGHT is at 520A for almost a day; IG currently at 1.3e-5 Torr (coming down), see attachment #2.
Auto cooling initiated at 2A/min.
The chamber will be vented with Ar.
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