Wednesday, September 26, 2012, 15:07
The samples were made of BeO powder with 30% PVB which was treated at 400 RPM for 26 minutes. A ratio of 10:1 of mineral oil was added before another high speed treatment for 10 minutes. The powder was then pressed into pellets.
Three pellets were loaded on the target boat coated with TaC, with an extra layer of TaC coated Ta foil. See Attachment 1. The target boat is wrapped with a Ta foil that is 0.002 inches thick.
Target chamber was pumped down. The cooling water was turned on and no leak were observed.
TGHT was stepped up to 55A before the auto ramping was initiated at 0.5 A/min. The vacuum limit parameter was set for good vac at <3.0 e-5 Torr and bad vac at >4.0 e0-5 Torr.
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