Tuesday, January 19, 2016, 14:19

SiC nanofiber was prepared at UBC Material Engineering Sci.  

4 samples are loaded in a Ta target contained (sintered with TaC coating): 

Sample 1: 

size:  21.70 x 21.54 mm, mass: 0.0762g, thick: 0.224mm

Sample 2: 

size: 20.89mm x 23.95mm, mass: 0.0954g, thick: 0.232mm 

--> Sample 1 and 2 with graphite backing foil 

Sample 3: 

size: 22.55 x 25.56mm, mass: 0.0082g, thick: 0.110mm

Sample 4: 16.93 x 23.82mm, mass: 0.0048g, thick: 0.086mm

--> Sample 3 and 4 with no graphite backing foil. 

(see attachment) 

Test#1:  Heating temperature at 1600C for 24hrs. 

TGHT will be adjusted accordingly.  There are 2 Ta-heat shields wrapped around the container. 

Chamber is currently being pumped down.

 Tuesday, January 19, 2016, 16:19

Vacuum at 2.0e-6 Torr.

For 1600C, expected current is around 350A.

Stepping up TGHT gradually...

 Wednesday, January 20, 2016, 14:34

TGHT was ramped up to 390A/6.63V to reach 1600C.  Samples have been heated at that temp since 11pm last night.

Visual check on the fibers seem ok (see attachment).

Will continue to heat this for a total time of 24hours.

 Wednesday, January 20, 2016, 22:57

Samples have been heated at 1600C for 24hours. 

Initiated cooling at 1A/min.

 Wednesday, January 27, 2016, 12:34

First attempt - heating 1600C.  XRD result showed board "bumps" that could be SiO2? It is inconclusive. 

Second attempt - re-heating the same samples, namely

Sample 1 - only the fiber

Sample 2 - with graphite backing.  This sample is loaded with the fiber facing down to see how well it holds on the graphite foil.  (see attachment)

TGHT will be ramped up to reach 1800C

Chamber is currently being pumped down.

 Wednesday, January 27, 2016, 14:04

Water valves open; no leaks detected.

Ramping up TGHT to 400A at 2A/min

 Wednesday, January 27, 2016, 18:08

TGHT is at 481A to obtain 1800C.

Visual check on Sample 2 - fiber has fallen off graphite backing foil.

Will remain heated at this temperature for over night.

 Friday, February 12, 2016, 11:11

Heat treatment test#1 is complete.  XRD results are inconclusive.  Need to do EDX to determine Si/SiO2.  

(See my dropbox for more details)