Tuesday, May 08, 2018, 15:02
22 np-SiC fibrous discs loaded in the tube container (coated and sintered with TaC)
Heat treatment is similar to previous process, see elog #408.
TGHT should be set at 330A/5.2V to reach temp 1575C (+/- 25).
Omega slope set at 1.05 (for carbide)
Chamber is currently being pumped down
Tuesday, May 08, 2018, 22:46
Pressure at 2.2e-6 Torr.
Initiated autoramping at 0.2A/min to reach 330A
Friday, May 11, 2018, 11:11
TGHT reached to 330A/5.1V but temp was measured at 1400A; It was held at that current for about 10 hours.
Increased TGHT to 335A/5.2V - temp is holding at 1420C (Will check the window if there is any coating that might have caused the discrepancy)
Sunday, May 13, 2018, 00:25
In fact, the window is slightly coated. The temperature should already be at optimum, 1600C. Will keep heating for another day.
Sunday, May 13, 2018, 14:10
Temp holding up well.. Pressure at 1.8e-7 torr.
cooling down at 2A/min.
Monday, May 14, 2018, 09:33
Target has been cooled for over 18 hours. Pressure at 1.1e-7 Torr.
Venting chamber.
mass loss = (8.65 - 4.32)g = 4.33 g (50%) [slightly higher than expected, likely due to increase of 5A on TGHT]
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