Laura Lambert wrote:

Tuesday, August 25, 2015, 11:50 Container coated with TaC using new method: Ends tapped off,  with liquid poured in and swirled around entire container, then poured back out - 'flushing technique' Container is wrapped with 3 x Ta heat shields, not incl center block. Loaded into EVAP2 and currently pumping down.  Tuesday, August 25, 2015, 13:52 IGP1 = 2.2e-6 Torr. HS water valves opened. No leaks detected. Tapped up manually to 35A. Vacuum stable. Initiated auto ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints for TGHT = 720A and TBHT = 230A, with final desired temp of 1800C  Wednesday, August 26, 2015, 09:56 IGP1 = 8.8e-7 Torr. TGHT = 260A, 3.0V TBHT = 145A, 1.8V Increasing ramping rate to 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.  Wednesday, August 26, 2015, 14:15 IGP1 = 3.5e-6 Torr. TGHT = 720A, 11.3V TBHT = 230A, 3.2V DV = 5.48V OMEGA RS [right side-old port] = 1745C OMEGA LS [left side-new port] = 1880C Tapping up manually to achieve 1800C on OMEGA RS  Wednesday, August 26, 2015, 14:44 IGP1 = 3.7e-6 Torr. TGHT = 748A, 11.9V DV = 5.78V OMEGA RS = 1803C OMEGA LS = 1935C Thursday, August 27, 2015, 07:31  Remained at max setpoints for ~17hrs. IGP1 = 1.3e-6 Torr. DV = 5.79V OMEGA RS = 1862 [this reading may not be correct due to the laser being moved at max setpoint - this temperature reading may be taken from a different location then the last reading] OMEGA LS = 1955 Initiating auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Thursday, August 27, 2015, 16:34

Target is removed from the evaporator and inspected.  

The "flushing technique" has a much better result.  The inner coated surface is sintered well.  

 Thursday, January 14, 2016, 11:47

Backing pump was making very loud high pitched noises during last couple processes in the evaporator.

Replaced with a new one this morning.

Thursday, February 25, 2016, 18:04 Wednesday, February 24, 2016, 17:29

Heat treatment of 2 bullet-shaped Nb samples in a LP-SIS container; it is just that we don't have a target boat. 

Container is wrapped with 12" in total length.  A strip of Nb foil is used as an underlayer for the samples to sit on top. 

Chamber has been pumped down and current vacuum at 1e-6 Torr. 

HS water check - good.

Target temperature 1400C

Ramping up to 250A; this should get to ~1300C.  Will let it heat for over night and step up to 1400C tomorrow. 

 Wednesday, February 24, 2016, 17:59

I'm stopping the heating process because the camera is not working.  I can't monitor the temperature.  Tried to fit the camera; don't now why it fails to connect to the server. 

Will look in to it tomorrow...

 Thursday, February 25, 2016, 08:17

Initiated auto ramping TGHT at 2A/min.

Thursday, February 25, 2016, 17:33  

Finally the camera is fixed.  

Current temperature is at 1126C, TGHT at 250A.  Will step up to reach 1400C. 

Thursday, February 25, 2016, 18:04  

TGHT stepped up to 335A to reach 1400C.  (see attachment) 

Will heat this for few hours and cool it at around 11pm tonight.

 Thursday, February 25, 2016, 22:19

Samples have been heated over 4.5 hours. 

Initiated cool down at 1A/min.

 Friday, February 26, 2016, 15:43

done! all good.

Friday, February 26, 2016, 15:44

5 samples were prepared at UBC MTRL using Sol-gel tetraethyl orthosilicate (TEOS) coated on electrospun polyacrylonitrate (PAN). 

Each sample is sandwiched in between graphite foils. 

Sample labeling:

Direct, 0.2358g

Mix, 0.3486g

3X, 0.2273g

5x, 0.2079g

7x, 0.1735g

All samples are loaded in the target boat, stacking on each other.  The Container is wrapped with 2X- Ta shields.

Chamber is pumping down. 

Step#1 Carbonization temperature: 1600C

 Saturday, February 27, 2016, 10:07

Vac at 2.5e-7 torr.

Ramping up TGHT to 300A at 1A/min. monitoring temp.

Saturday, February 27, 2016, 17:38

TGHT at 400A, temp at 1600C. Vac 1.34e-6 Torr.

 Monday, February 29, 2016, 13:04

Samples have been heated at 1635C for almost 2 days. 

Pressure at 2.1e-7 Torr.

Initiated cooling at 2A/min.

 Thursday, March 24, 2016, 11:26

Samples were analyzed for Si using EDX.  Unfortunately, no Si was found.  The vapour pressure of SiO was too high for it to react with PAN to carbonize in a vacuum environment.  

Will look into a different technique.

Thursday, March 24, 2016, 11:37  

SiC powder (<1um) [10%] was mixed with PAN solution [10%].  Solution was sonicated before e-spinning.  

Fiber mat was binded to graphite foil and heat treated to 250C in air for 1 hour.  

Samples were cut in pieces and rolled up and inserted in Ta target container (TaC coated).  Heat shield was added.

Heat Treatment #1:  

Temperature:  1600C (~350A)

Ramping up TGHT to 300A at 1A/min.  

 Tuesday, March 29, 2016, 11:11

TGHT was maintained at 410A for 1600C for 2 days (see attachment 1).  However at around 22:30 on March 28, there was a sudden increase in voltage.

Temperature raised up to 1750C.  Not sure there was a fault with the control system and it was caused by the Ta-heat shield. (see attachment #2).

 Target was cooled down around 2am on March 29. 

Samples will be removed from the chamber.

Thursday, April 07, 2016, 15:18

E-spun SiC/PAN fiber mats were produced at UBC.

12%PAN solution; 50% SiC to weight of PAN.

Materials used:

1.2g PAN, 8.8g DMF, 0.6g SiC, SDS ~0.1% to SiC

Fiber mats were heat treated at 250C in air.  Then cut into 18" discs and loaded into Ta target boat with heatshield wrapped. 

3 temperature treatments will carry out: 1200C, 1400C and 1600C

Chamber is being pumped down

 Friday, April 08, 2016, 10:02

TGHT at 285A, Temp at ~1200C.  Will remain at this temp for a few hours before cooling down. 

Some samples will be taken out for analysis. 

Next week, temperature treatment will continue at 1400C

 Friday, April 08, 2016, 14:26

Samples have been heated at 1200C for just over 4 hours.

Initiated auto-cooling at 2A/min

 Tuesday, April 12, 2016, 17:51

Heat treatment #2 - 1400C. 

Initial mass after 1200C = 0.0312g

 Monday, April 18, 2016, 12:55

Samples was heated at 1400C (TGHT maintained at ~370A) for 4 days (see attachment 1).

Chamber is vented; samples will be inspected.

 Tuesday, April 19, 2016, 17:49

Results

Sample mass after 1200C = 0.0312g

Sample mass after 1400C = 0.0294g

~5.78% mass  loss. 

Tuesday, April 19, 2016, 17:57

Heat Treatment#3: 1600C

sample mass before heating = 0.0238g (this sample is taken from the batch after it was heated at 1400C)

Chamber is being pumped.

 Thursday, April 21, 2016, 11:07

TGHT stepped up to 330A, temp measured at 1422C.

 Thursday, April 21, 2016, 12:05

TGHT at 415A/7.16V; temp at 1610C

 Thursday, April 21, 2016, 17:49

Temp dropped to 1590.  Increased TGHT to 425A; temp reads 1602A.

 Friday, April 22, 2016, 10:57

Voltage increased to 7.33V, TGHT stepped down to 418A, temp maintained at 1610A.

 Monday, April 25, 2016, 12:08

Sample was heat treated for almost 4 days.  Temperature dropped to 1578C, TGHT at 418/7.26V.  (see attachment #2)

Ramping down TGHT 2A/min.

 Monday, April 25, 2016, 16:00

Result:

Mass after 1600C = 0.0104g, 5.63% mass loss. 

Will do XRD/EDX

 Tuesday, May 03, 2016, 14:29

Turned vacuum pump on this morning, sounded awful: loud grinding bad noises.

Called vacuum group, will replace pump tomorrow morning.

Sounds like materials coming out from all the out-gassing during sintering processes has ruined the bearings.

Wednesday, May 11, 2016, 17:15

Nanofiber SiC (~50nm grain size)/PAN was prepared at UBC. 

SiC 0.50g, DMF 9.0g, PAN 1.0g, tiny bit of SDS.

The fiber mat was stabilized in air at 250C and then cut into discs, initial mass = 0.1072g

Discs were then bounded with PVA on 9 pieces of rounded graphite foil  (green mass gained to 0.6031g)

The stack of naofiber SiC/PAN was loaded on to Ta boated (coated) and wrapped with Ta heat shield. 

Chamber is currently being pumped down.

 Friday, May 13, 2016, 15:00

TGHT at 390A/6.966V.  Temp measured at 1615C. 

Will keep at that temperature for a few days.

 Monday, May 16, 2016, 15:44

Sample has been heated at ~1600C for 4 days.  TGHT at 400A/7.02V. 

Cooling down at 2A/min

 Tuesday, May 17, 2016, 11:18

Chamber vented.  Inspecting samples.

The purpose of this experiment is to determined the limiting operating temperature for Beta-SiC.  To do so, samples will be heated in sequence to observe any volatile Si coated on the window.  The coating is observed above 1400C for the conventional SiC (mixuture of alpha and beta) and this coating leads to HV shorting problem. 

Thursday, May 19, 2016, 14:26

Beta-SiC (size ~1um) slurry was prepared and casted on a graphite foil. 

Discs are cut into D-shape

Average thickness (including graphite foil) = 0.349mm

Graphite foil = 0.13mm

Actual SiC thickness = 0.219mm (close to normal SiC thickness)

Samples are loaded into a target boat.

Total discs = 120

Total mass = 14.3507g

Thursday, May 19, 2016, 14:32

Omega slope set to = 1.04

Heat-treatment #1: 1400C

 Thursday, May 19, 2016, 17:04

TGHT ramping up to 250A at 0.5A/min

John Wong wrote:

The purpose of this experiment is to determined the limiting operating temperature for Beta-SiC.  To do so, samples will be heated in sequence to observe any volatile Si coated on the window.  The coating is observed above 1400C for the conventional SiC (mixuture of alpha and beta) and this coating leads to HV shorting problem.  Thursday, May 19, 2016, 14:26 Beta-SiC (size ~1um) slurry was prepared and casted on a graphite foil.  Discs are cut into D-shape Average thickness (including graphite foil) = 0.349mm Graphite foil = 0.13mm Actual SiC thickness = 0.219mm (close to normal SiC thickness) Samples are loaded into a target boat. Total discs = 120 Total mass = 14.3507g Thursday, May 19, 2016, 14:32 Omega slope set to = 1.04 Heat-treatment #1: 1400C  Thursday, May 19, 2016, 17:04 TGHT ramping up to 250A at 0.5A/min

 Friday, May 20, 2016, 08:53

IGP1 = 9.2e-6 Torr.

Increasing ramping rate to 1.0A/min up to 250A

 Friday, May 20, 2016, 09:17

IGP1 = 2.1e-5 Torr

TGHT = 215A, 3.1V

OMEGA = 1035C

Stopping auto-ramp and tapping up manually...

 Friday, May 20, 2016, 12:26

OMEGA slope changed to 1.04

OMEGA reached ~1430C and kept there for ~1hr.

no change. no coating on window observed

tapped up manually to OMEGA =1500C

TGHT = 350A, 5.8V

 Friday, May 20, 2016, 14:17

Not much change to window.

Might be beginning of light dusting, hard to tell.

Will be better observed after longer period of time at 1500C

Will remain at 1500C over weekend.

Laura Lambert wrote:

John Wong wrote: The purpose of this experiment is to determined the limiting operating temperature for Beta-SiC.  To do so, samples will be heated in sequence to observe any volatile Si coated on the window.  The coating is observed above 1400C for the conventional SiC (mixuture of alpha and beta) and this coating leads to HV shorting problem.  Thursday, May 19, 2016, 14:26 Beta-SiC (size ~1um) slurry was prepared and casted on a graphite foil.  Discs are cut into D-shape Average thickness (including graphite foil) = 0.349mm Graphite foil = 0.13mm Actual SiC thickness = 0.219mm (close to normal SiC thickness) Samples are loaded into a target boat. Total discs = 120 Total mass = 14.3507g Thursday, May 19, 2016, 14:32 Omega slope set to = 1.04 Heat-treatment #1: 1400C  Thursday, May 19, 2016, 17:04 TGHT ramping up to 250A at 0.5A/min    Friday, May 20, 2016, 08:53 IGP1 = 9.2e-6 Torr. Increasing ramping rate to 1.0A/min up to 250A  Friday, May 20, 2016, 09:17 IGP1 = 2.1e-5 Torr TGHT = 215A, 3.1V OMEGA = 1035C Stopping auto-ramp and tapping up manually...  Friday, May 20, 2016, 12:26 OMEGA slope changed to 1.04 OMEGA reached ~1430C and kept there for ~1hr. no change. no coating on window observed tapped up manually to OMEGA =1500C TGHT = 350A, 5.8V  Friday, May 20, 2016, 14:17 Not much change to window. Might be beginning of light dusting, hard to tell. Will be better observed after longer period of time at 1500C Will remain at 1500C over weekend.

 Tuesday, May 24, 2016, 11:15

Sample has been heated over the long weekend.  Temp dropped to 1400C.  TGHT at 350A/5.78V.  Vac at 1.5e-7 Torr.

It is hard to tell if there is any coating on the window.  Will increase temperature to 1800C

 Tuesday, May 24, 2016, 11:43

Temp at 1620C. TGHT at 440A/7.7V. 

At this temperature, the coating would have been seen for the conventional SiC target material.  But, no much of change on the window since the TGHT was tapped up from 1400C.

Continue to increase TGHT to reach 1800C

 Tuesday, May 24, 2016, 11:58

Temp at 1680C/TGHT 470A/8.4C - a very light film on the window was observed.  Not sure if this film was left from previous processes; it is just that the target container is getting very bright and hard to see.

 Tuesday, May 24, 2016, 12:15

TGHT at 510A/9.16V - Observed coating on window.  Omega got interfered, therefore temp is unknown.  But it was read at ~1720C before the window was getting coated and temp started to dropped.

Will leave at this stage for now...

 Tuesday, May 24, 2016, 16:57

Window is fully coated.  Based on the heating curve, at 500A, the temp should be at ~1900C (wrapped with a layer of heat shield).  Temperature reader dropped to1340C due to the coating interference. 

Cooling down TGHT at 2A/min. And will exam the materials tomorrow... 

Wednesday, August 03, 2016, 16:16

Tues July 26th had some problems with the transfer chamber

Transfer chamber was not going below -20in pressure, when usually it will drop all the way to -30in

To by pass and put the uranium target into the glove box, the transfer chamber was flushed 10x - when opened, no change in H2O and O2 in glove box; therefore, 'bypass' worked.

Pump removed and tested by vacuum group - showed no reading on gauge when being tested, how was it even pumping?

New pump installed July 27th.

New pump = bigger/ faster/ quieter 

 Dan made a set of new cooling lines for the Source Tray Heat Shield cooling yesterday. No joints on the lines. Use same VCR fitting 3/8 -> 1/4" as for the Heat Shield. The old lines had worn threads on the male VCR nut.

Monday, October 24, 2016, 17:43

Two samples were prepared and loaded into the target boat with 1 layer of heat-shied as shown in the attachment#1.

Ingredients used: np-SiC and very small about of 5% PVA to hold the powder together. 

Samples were dried in the oven at 110C before loaded in Evap#2. 

After dried:

Sample #1 (larger graphite boat, mass =0.3779) = 0.4259g (PVA mass unknown due to solution leaking out from the boat)

Sample #2 = 0.2306g (with 5% PVA of 0.4111g)

Test temperature at 1600C, expect TGHT to be around 400A. 

Monday, October 24, 2016, 17:50

Ramping up TGHT to 300A at 0.5A/min. Vac at 2.3e-6 Torr. 

 Tuesday, October 25, 2016, 12:59

TGHT reached to 300A and stabilized for 10 hours.  OMEGA temp reader at 1150C

Continue to ramp up TGHT

 Wednesday, October 26, 2016, 15:49

TGHT was ramped up to 450A/7.91V; the temp readers on MIKON and OMEGA were 1489 and 1535, respectively (see attachment).

The temperature was much lower than the previous two tests (see elog #296 and #335).  Not sure why... 

Will do composition analysis on the sample... 

Cooling down at 2A/min.

Tuesday, November 15, 2016, 16:48

Three samples were prepared  (see my logbook#1 page 3, preparing for carbonization).

One layer of Ta foil was used to wrap around the target boat. 

Chamber is currently being pumped down

 Wednesday, November 16, 2016, 11:04

Ramping up TGHT at 2A/min, set at 350A.

Desired temperature, ~1530C (similar heating condition as raw npSiC heat treatment, elog ID335)

 Thursday, November 17, 2016, 10:09

TGHT reached to 350A/5.80V, stayed for over 20 hours.  Temp measured at 1276 C (Mikon) and 1270 (Omega), vac at 6.07e-7 Torr. 

Stepping up TGHT to reach the desired temp.

John Wong wrote:

Tuesday, November 15, 2016, 16:48 Three samples were prepared  (see my logbook#1 page 3, preparing for carbonization). One layer of Ta foil was used to wrap around the target boat.  Chamber is currently being pumped down  Wednesday, November 16, 2016, 11:04 Ramping up TGHT at 2A/min, set at 350A. Desired temperature, ~1530C (similar heating condition as raw npSiC heat treatment, elog ID335)  Thursday, November 17, 2016, 10:09 TGHT reached to 350A/5.80V, stayed for over 20 hours.  Temp measured at 1276 C (Mikon) and 1270 (Omega), vac at 6.07e-7 Torr.  Stepping up TGHT to reach the desired temp.

 Thursday, November 17, 2016, 11:13

TGHT = 400A, 6.73V

IGP1 = 8.2e-7 Torr

OMEGA = 1385C

MIKRON = 1389C

Tapping up manually to 1500C or a max setpoint of 450A

Thursday, November 17, 2016, 11:56

TGHT = 450A, 7.85V

IGP1 = 1.7e-6 Torr

OMEGA = 1502C

MIKRON = 1510C

 Friday, November 18, 2016, 10:08

IGP1 = 5.3e-7 Torr

TGHT = 450A, 7.9V

OMEGA = 1510C

MIKRON = 1515C

Evap2 has remained at max setpoints for 23hrs.

Initiating auto-cool at 2.0A/min

Laura Lambert wrote:

John Wong wrote: Tuesday, November 15, 2016, 16:48 Three samples were prepared  (see my logbook#1 page 3, preparing for carbonization). One layer of Ta foil was used to wrap around the target boat.  Chamber is currently being pumped down  Wednesday, November 16, 2016, 11:04 Ramping up TGHT at 2A/min, set at 350A. Desired temperature, ~1530C (similar heating condition as raw npSiC heat treatment, elog ID335)  Thursday, November 17, 2016, 10:09 TGHT reached to 350A/5.80V, stayed for over 20 hours.  Temp measured at 1276 C (Mikon) and 1270 (Omega), vac at 6.07e-7 Torr.  Stepping up TGHT to reach the desired temp.    Thursday, November 17, 2016, 11:13 TGHT = 400A, 6.73V IGP1 = 8.2e-7 Torr OMEGA = 1385C MIKRON = 1389C Tapping up manually to 1500C or a max setpoint of 450A Thursday, November 17, 2016, 11:56 TGHT = 450A, 7.85V IGP1 = 1.7e-6 Torr OMEGA = 1502C MIKRON = 1510C  Friday, November 18, 2016, 10:08 IGP1 = 5.3e-7 Torr TGHT = 450A, 7.9V OMEGA = 1510C MIKRON = 1515C Evap2 has remained at max setpoints for 23hrs. Initiating auto-cool at 2.0A/min

 Friday, November 18, 2016, 17:27

The heat treatment of the fiber mats is done. 

Analyzing steps...

Tuesday, December 20, 2016, 15:05

confirmed ~full tank of Ar for glove box --> ~1600psi 

 Friday, February 03, 2017, 14:17

The endcaps are stacked together with a punched out disc of graphite foil placed in between each endcap for separation so endcaps won't fuse together.

The end caps are further wrapped in a larger piece of graphite foil to hold together as a tube [same method used in elogID # 158 and 235]

There are also 4 coated springs, 2 on each side of the endcaps tube, with the endcaps tube residing in the middle of the boat.

The boat is wrapped with 3-layers of Ta heatshields.

Chamber is currently being pumped down.

Good vac at 3.0e-5, bad vac at 4.0e-5 Torr.

OMEGA slope = 0.98

 Monday, February 06, 2017, 09:29

Power outage this weekend and evap2 tripped off.

Re-pumping down now...

 Tuesday, February 07, 2017, 08:54

HS water valves opened, no leaks detected.

IGP1 = 1.9e-7 Torr

Tapped up manually to 35A

Vacuum stable.

IGP1 = 2.0e-7 Torr

Initiating auto-ramp at 0.2A/min with a final setpoint of 450A.

Final desired temperature = 1800C

 Wednesday, February 08, 2017, 09:52

IGP1 = 2.98e-7 Torr

TGHT = 325A, 3.5V

Vacuum stable.

Increasing ramping rate to 1.0A/min

 Wednesday, February 08, 2017, 11:46

IGP1 = 6.3e-7 Torr

TGHT = 433A, 4.89V

Increasing max setpoint to TGHT = 500A

OMEGA has still yet to show a temperature...should be reading points at this high in current

Will go down to the lab and follow up on OMEGA settings to confirm everything is set up ok before proceeding to a higher current...

 Wednesday, February 08, 2017, 16:03

IGP1 = 4e-7 Torr

TGHT = 500A, 5.75V

OMEGA still not reading

Initiating auto-cool at -2A/min

Will update elog with more details tomorrow

 Thursday, February 09, 2017, 10:52

Evap2 was cooled down and opened up this morning.

Turns out both legs on the target boat were touching the new heatshield and therefore had been loosing power.

Normally a boat at 500A would read ~1800C, in this scenario at 500A the boat read ~1000C.

A lot of power was being lost into the heatshield.

See photos attached of target boat sitting at 500A.

The heatshield is currently being ground down in those two spots to accommodate the target boat.

 Dave Morris did a remote restart of the IOC after the outage. Turbo pump started.