Monday, May 14, 2012, 15:04

Due to the differences in the use of the graphite foils in past SiC targets (C-grv foil from Alpha Aesar) and the newly prepared SiC#27 (C-grv foil from Ceramaterial), the out-gassing period for SiC#27 took over 6 days compared to 3 days for the vacuum to come down (see https://elog.triumf.ca/TIS/Evaporator_1/47). 

A few pieces of the new graphite foil is loaded on the target boat to test the out gassing reaction. 

The Evap #1 chamber has been pumped down to low 10e-5. 

Set to same parameter, see attachment#1

Initiated auto heating...

 Tuesday, May 15, 2012, 14:46

The target heater was ramped up to 820A.  There was so much out gassing as the temperature was increased.  The voltage did not hold at that current and the target heater was tripped off after the midnight.  (see attachment #2)

After the chamber was vented, it was discovered that the target boat's legs were bent due to over heating.  Both end of the targets where they touched the base got vaporized.  The boat was also got squeezed.  (see attachment #3).  

However, the heated graphite foils (~1600C at 820A) looks pretty good.  As per the supplier, CeraMaterials, the graphite was treated to 2000C.  See attachment #4 for the certificate.