Tuesday, July 26, 2016, 16:50

loaded into evap2

pumped down, HS water valves opened, no leaks detected.

tapped up manually to 35A

vacuum stable = 3.8e-6 Torr

Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively.

Final setpoints at 230A for the TBHT and 600A for the TGHT.

Final desired temperature = 1800C

 Wednesday, July 27, 2016, 09:20

IGP1 = 6.3e-7 Torr, vacuum stable.

TGHT = 232A, 2.7V

TBHT = 131A, 1.76V

Increasing ramping rate to 1.0A/min and 0.5A/min for the TGHT and TBHT respectively.

 Wednesday, July 27, 2016, 15:46

TGHT = 600A, 8.87V

TBHT = 230A, 3.7V

IGP1 = 1.37e-6 Torr

OMEGA = 1640C

Increased max TGHT voltage to 12V

Tapped up manually to OMEGA = 1810C

TGHT = 675A, 10.21V

IGP1 = 2.2e-6 Torr

Will remain at max setpoints for the rest of the week and cool down over weekend.

 Thursday, July 28, 2016, 08:34

TGHT = 675A, 10.41V

OMEGA = 1833C

Tapped down to 660A, 10.09V

OMEGA = 1805C

 Friday, July 29, 2016, 13:57

OMEGA = 1814C

TGHT = 660A, 10.16V

TBHT = 230A, 3.72V

IGP1 = 3.43e-7 Torr

evap2 has remained at max setpoints for ~42hrs

conditioning complete.

Initiating auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Tuesday, August 02, 2016, 13:39

vented in air and removed from evap2 this morning.

target looks good!

 Friday, July 15, 2016, 11:49

Container previously coated with TaC using 'flushing technique', cleaned ionizer tube with acetone, so no coating inside ionizer tube

Wrapped with 3 x Ta heat shields, incl center block - new method of each layer being one long single Ta foil covering entire container incl center block

Currently pumping down in evap2

 Friday, July 15, 2016, 14:35

Turbo pump broken 

Currently being replaced...

 Friday, July 15, 2016, 17:04

Turns out its not the turbo pump...TP controls and pump replaced, problem still happening.

Took out heat shield and used a closed loop to rule out leak in chamber, emptied all water lines - turbo pump now on.

Took v.long time to pump down. TP will remain on over wknd.

BP turns on, PV1 turns on, RV turns on - then takes very long time for vacuum to drop ~45min? before BV and TP can be turned on.

Possibly problem with threads on heat shield and not creating proper seal?

Will continue monday with evap2 mystery problem solving...

Monday, July 18, 2016, 16:14

Replaced heat shield and copper seals.

Container re-loaded.

Turbo pump on and good vacuum achieved! YAY!

Finished pumping down, opened HS water valves - no leaks detected.

Tapped up manually to 35A

Vacuum stable, IGP1 = 3e-6 Torr

Initiating auto ramp for TGHT @ 0.2A/min to a max setpoint of 400A

Initiating auto ramp for TBHT @ 0.1A/min to a max setpoint of 230A

Once max setpoints achieved, will tap up manually to final desired temperature of 1900C

 Tuesday, July 19, 2016, 09:21

TGHT = 242A, 2.76V

TBHT = 162A

IGP1 = 5.05e-6 Torr

Increasing ramping rate to 1.0A/min and 0.5A/min for the TGHT and TBHT respectively.

 Tuesday, July 19, 2016, 13:04

TGHT = 400A, 4.4V

TBHT = 230A, 2.6V

OMEGA = 1120C

Reached max setpoints ~1hr ago.

Tapping up manually to 1900C...

Tuesday, July 19, 2016, 16:32

MORE problems with evap2 

TGHT reads 460A, 5.1V, 1170C - a lot of power is being lost somewhere...

Comparison from elog i.d. 291 [the last IGLIS container sintering of TaC coating] the TGHT read 460A, 7.5V, 1900C

Another problem: the read out on the power supply and read out on epics of the TBHT reads 215A; however, the 'current set' says 177A - two very different numbers?!

Ramping down evap2 at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively to further inspect chamber and hopefully solve this...

 Wednesday, July 20, 2016, 13:34

Chamber was vented in air and opened up for inspecting.

Fixed!

One of the steel plates used to stop reflection onto the door of the chamber was inserted improperly, resting on top of the 2 negative copper lines to the target leg, this was causing a short.

There was also a short from the right target leg touching the copper heat shield, the heat shield has been shaved down and corrected. It is no longer touching.

There were also 2 brackets that had fallen behind evap2 inside the cage, one was touching the positive lines - it wasn't quite touching the ground, but may have grounded it, causing another possible short.

The chamber was pumped back down and the HS water valves re-opened. No leaks detected.

Evap2 was tapped up manually to 35A.

Vacuum stable = 1.0e-6 Torr.

Initiating auto-ramp at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

Final setpoints are TGHT = 400A and TBHT = 230A

 Wednesday, July 20, 2016, 16:25

TGHT = 315A, 4.5V

TBHT = 174A, 2.1V

IGP1 = 2e-6 Torr

OMEGA = 1518C

Lowering auto-ramp to 0.2A/min and 0.1A/min for the TGHT and TBHT overnight while unable to keep watch on the vacuum.

 Thursday, July 21, 2016, 09:09

Evap 2 reached max setpoints ~7.5hrs ago.

TGHT = 400A, 6.3V

TBHT = 230A, 2.9V

IGP1 = 5.1e-7 Torr.

OMEGA = 1882C

Tapping up manually to 1900C...

 Friday, July 22, 2016, 16:18

Container has remained at ~1900C for ~31hrs

TGHT reached 405A/1900C - then after ~23hrs dropped in temperature down to 1895C so was tapped up further to 410A/1910C for another ~8hrs.

TGHT = 410A, 6.57V

IGP1 = 3.1e-7 Torr

TBHT = 230A, 2.9V

Initiating auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

Will remove from evap2 after the weekend.

 Tuesday, July 26, 2016, 16:49

vented in air.

container looks good, fully sintered.

will update with photos tomorrow...

 Monday, June 27, 2016, 11:07

Container coated with TaC using 'flushing technique'.

Wrapped with 3 x Ta heat shields, incl center block - new method of each layer being one long single Ta foil covering entire container incl center block

Currently pumping down in evap2

 Monday, June 27, 2016, 13:23

HS water valves opened

Tapped up manually to 35A

Waited ~1hr, vacuum stable

IGP1 = 1.8e-6 Torr

Initiating auto ramp for TGHT @ 0.2A/min to a max setpoint of 400A

Initiating auto ramp for TBHT @ 0.1A/min to a max setpoint of 230A

Once max setpoints achieved, will tap up manually to final desired temperature of 1900C

 Wednesday, June 29, 2016, 11:33

IGP1 = 1.9e-7

TGHT = 400A, 6.0V

TBHT = 223A, 3.9V

OMEGA = 1885C

Remained at these settings for ~13hrs

Increased TBHT max voltage to 4.3V to achieve 230A

TBHT = 230A, 4.1V

OMEGA = 1890C

Tapped up to TGHT = 405A, 6.17V to achieve 1900C...OMEGA reached 1915C

Lowered TGHT to = 403A, 6.12V

OMEGA = 1905C

Measured ~1870C with the mikron, same window the OMEGA measurements are taken out of.

IGP1 = 2.1e-7

 Thursday, June 30, 2016, 08:44

TGHT = 403A, 6.07V

OMEGA = 1886C

Tapped back up to 1900C

TGHT = 410A, 6.22V

OMEGA = 1911C

Thursday, June 30, 2016, 16:01

OMEGA = 1911C

Container has remained at ~1900C for ~1.5 days

Initiating auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Monday, July 04, 2016, 09:59

Vented in air and opened up this morning.

Container looks good.

Confirmed coating fully sintered with J.Wong.

Photos attached.

 Thursday, June 16, 2016, 10:59

Previously sintered over weekend [see elog i.d 306]

Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs]

Target packed length = 16cm. 

Mass of 533 discs SiC(green)  = 53.8758g

Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place.

Conditioning temp = 1800C.

TGHT max = 710A according to sintering data.  TBHT max = 230A. 

Chamber is currently being pumped down. 

 Thursday, June 16, 2016, 15:43

Target was not removed from evap2 after sintering, vented and cleaned windows only.

HS water valves already open.

Stepped up manually to 70A, vacuum stable.

Initiated auto-ramp at 1.0A/min for the TGHT and 0.5A/min for the TBHT with max setpoints of 600A and 230A respectively.

TGHT = 118A, 0.9V

TBHT = 90A, 1.1V

IGP1 = 7.3e-7 Torr

 Friday, June 17, 2016, 12:14

TGHT has been tapped up manually to reach max desired temperature of 1800C

TGHT = 690A, 10.85V

TBHT = 230A, 3.88V

IGP1 = 4.9e-7 Torr

This is a lower current than the current required to reach 1800C during the sintering process.

For sintering, the max current was determined via extrapolation of trendline from raw data due to interference of coating on window and unable to take reliable readings from OMEGA.

For this conditioning process ~1800C is reached on the OMEGA since the window is still ~un-coated.

Will remain at 690A, ~1800C for several days to maximize conditioning process.

See attachment for raw data.

 Monday, June 20, 2016, 09:01

At the end of the day on friday 17th, OMEGA read ~1750C - no change in the current or voltage, vacuum was stable, this was the max setpoints used to reach 1800C.

This morning OMEGA = 2040C

TGHT = 690A, 10.95V

vacuum stable at IGP1 = 1.8e-7 Torr.

Slightly more noticeable coating on window port, looks like a thin ink layer, still relatively thin coating [ see attached image]

Also attached is archive from over wknd to show vacuum stable, current unchanged and voltage negligibly changed [only gone up by ~0.1V]

 Friday, June 24, 2016, 13:52

Container has remained at max setpoints for 7 days.

Initiating auto-cool for TGHT @ 2.0A/min and for TBHT @ 1.0A/min.

Will vent chamber and remove from evap2 to pass off for assembly monday morning.

See attachment for updated excel on temperature readings for the conditioning process.

 Monday, June 27, 2016, 08:28

vented in air and removed this morning.

target looks good!

all discs remained nicely alligned.

discs expanded outwards ~1cm, pushed back in to keep target length at 16cm

no visible yellow crystals like previous SiC targets 

endcaps inserted and expanded.

Rh foil inserted.

Ta heat shield foils removed, fins look good.

see photos attached for pictures of target - post conditioning.

coating on window very hard to remove. looked like a light sharpy pen coating on window. ended up scratching off with acetone and screw driver. couldn't remove all of it...

John Wong wrote:

Laura Lambert wrote: John Wong wrote:   Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.    Monday, June 13, 2016, 09:51 TGHT = 425A, 5.65V TBHT = 225A, 3.7V IGP1 = 8.7e-6 Torr. Increasing ramping rate to 1.0A/min...  Monday, June 13, 2016, 15:56 Tapped up manually from 520A to 1800C Extrapolated data on graph to determine correct current required to reach desired max temperature. Will remain at 1800C for ~48hrs See attachements for excel sheet and screenshot of striptool.    Wednesday, June 15, 2016, 17:54 TGHT at 710A, 11.35V.  TBHT at 230A/3.86V.  Omega reading droppd to 1130C due to coating on windows.  Ionizer tube was measured (center) at around 1900C Cooling down at 2A/min for TGHT, 1A/min for TBHT.  Samples will be collected prior to cleaning the windows. NEXT:  Conditioning.

Thursday, June 16, 2016, 09:29

vented in air and opened up this morning.

took some samples to be tested.

Laura Lambert wrote:

John Wong wrote:   Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.    Monday, June 13, 2016, 09:51 TGHT = 425A, 5.65V TBHT = 225A, 3.7V IGP1 = 8.7e-6 Torr. Increasing ramping rate to 1.0A/min...  Monday, June 13, 2016, 15:56 Tapped up manually from 520A to 1800C Extrapolated data on graph to determine correct current required to reach desired max temperature. Will remain at 1800C for ~48hrs See attachements for excel sheet and screenshot of striptool.

 Wednesday, June 15, 2016, 17:54

TGHT at 710A, 11.35V.  TBHT at 230A/3.86V. 

Omega reading droppd to 1130C due to coating on windows. 

Ionizer tube was measured (center) at around 1900C

Cooling down at 2A/min for TGHT, 1A/min for TBHT. 

Samples will be collected prior to cleaning the windows.

NEXT:  Conditioning.

John Wong wrote:

Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.

 Monday, June 13, 2016, 09:51

TGHT = 425A, 5.65V

TBHT = 225A, 3.7V

IGP1 = 8.7e-6 Torr.

Increasing ramping rate to 1.0A/min...

 Monday, June 13, 2016, 15:56

Tapped up manually from 520A to 1800C

Extrapolated data on graph to determine correct current required to reach desired max temperature.

Will remain at 1800C for ~48hrs

See attachements for excel sheet and screenshot of striptool.

 Friday, June 10, 2016, 16:27

TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V. 

Pressure stabilized at 5.5e-5 Torr.

Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.

 Thursday, June 09, 2016, 15:39

First target using beta-SiC material!

Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs]

Target packed length = 16cm. 

Mass of 533 discs SiC(green)  = 53.8758g

Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place.

Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A. 

Chamber is currently being pumped down. 

Friday, June 10, 2016, 13:24

HS water valves opened, no leaks detected.

Tapping up manually to 70A...

Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A

Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.

Laura Lambert wrote:

Wednesday, May 25, 2016, 11:37 Container coated with TaC using 'flushing technique' [cleaned ionizer tube with acetone, so no coating inside ionizer tube] Wrapped with 2 x Ta heat shields - one full height of Ta foil wrapped around cooling fins twice Currently pumping down in evap2  Thursday, May 26, 2016, 09:28 Tapped up manually to 40A IGP1 = 6.6e-7 Torr Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints for TGHT = 650A and TBHT = 230A Once max setpoints reached will continue to tap up manually while monitoring temperature to 1900C

 Tuesday, May 31, 2016, 11:09

TGHT at 615A/9.08V, temp = 1610C.  Vacuum at 1.8e-7 Torr. 

Tapping up TGHT to reach 1900C

 Tuesday, May 31, 2016, 12:04

TGHT at 765A/11.90V.  Temp at 1900C.  Pressure is coming down from 8.7e-7Torr. 

Will keep at this temperature for a day.

 Wednesday, June 01, 2016, 15:22

Temperature has been stable at 1900C.  Pressure is coming down from 3.4e-7 Torr. 

Cooling down TGHT and TBHT at 2A/min and 1A/min, respectively.

 Friday, June 03, 2016, 12:10

TGHT/TBHT at 0A.  Target can be remained under vacuum until Monday.

 Monday, June 06, 2016, 16:54

Target container was inspected; it looks good

 Wednesday, May 25, 2016, 11:37

Container coated with TaC using 'flushing technique' [cleaned ionizer tube with acetone, so no coating inside ionizer tube]

Wrapped with 2 x Ta heat shields - one full height of Ta foil wrapped around cooling fins twice

Currently pumping down in evap2

 Thursday, May 26, 2016, 09:28

Tapped up manually to 40A

IGP1 = 6.6e-7 Torr

Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively.

Final setpoints for TGHT = 650A and TBHT = 230A

Once max setpoints reached will continue to tap up manually while monitoring temperature to 1900C

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... 

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.

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

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.

John Wong wrote:

Laura Lambert wrote:  Wednesday, May 04, 2016, 13:28 Target boat has a layer of niobium foil on the bottom of the boat. A niobium foil has been made with slots to hold samples [similar to when sintering endcaps] *See attached photos Larger niobium samples are placed in the slots, holding in place, to avoid warping; smaller niobium sample sitting inside the boat by itself. Smaller sample closest to OMEGA IR reading [right side] Boat is wrapped with 1 large layer of Ta foil, wrapped around the boat 3x, careful to avoid touching samples. Loaded into evap2 yesterday. Vacuum pump bearings gone - pump replaced this morning by vacuum group. Pumping down now...  Friday, May 06, 2016, 13:36 HS water valves opened, no leaks detected. Tapped up manually to 35A. IGP1 = 2.4e-7 Torr Setting auto-ramp rate at 0.2A/min to 250A over the weekend. Will tap up manually monday to final desired temperature of 1400C.  Monday, May 09, 2016, 09:38 OMEGA = 1128C IGP1 = 1.3e-7 Torr TGHT = 250A, 3.7V Tapping up manually to 1400C...  Monday, May 09, 2016, 14:05 Evap2 has reached ~1405C TGHT = 341A, 5.34V IGP1 = 1.9e-7 Torr Will remain at max setpoints for min 4hrs then initiate cool down.    Monday, May 09, 2016, 18:18 TGHT at 341A/5.34V for over 4 hours.  Vac stables at 1.78e-7 Torr. Cooling down at 2A/min

 Tuesday, May 10, 2016, 08:45

Vented in air and opened up this morning.

Samples look good!

Laura Lambert wrote:

Wednesday, May 04, 2016, 13:28 Target boat has a layer of niobium foil on the bottom of the boat. A niobium foil has been made with slots to hold samples [similar to when sintering endcaps] *See attached photos Larger niobium samples are placed in the slots, holding in place, to avoid warping; smaller niobium sample sitting inside the boat by itself. Smaller sample closest to OMEGA IR reading [right side] Boat is wrapped with 1 large layer of Ta foil, wrapped around the boat 3x, careful to avoid touching samples. Loaded into evap2 yesterday. Vacuum pump bearings gone - pump replaced this morning by vacuum group. Pumping down now...  Friday, May 06, 2016, 13:36 HS water valves opened, no leaks detected. Tapped up manually to 35A. IGP1 = 2.4e-7 Torr Setting auto-ramp rate at 0.2A/min to 250A over the weekend. Will tap up manually monday to final desired temperature of 1400C.  Monday, May 09, 2016, 09:38 OMEGA = 1128C IGP1 = 1.3e-7 Torr TGHT = 250A, 3.7V Tapping up manually to 1400C...  Monday, May 09, 2016, 14:05 Evap2 has reached ~1405C TGHT = 341A, 5.34V IGP1 = 1.9e-7 Torr Will remain at max setpoints for min 4hrs then initiate cool down.

 Monday, May 09, 2016, 18:18

TGHT at 341A/5.34V for over 4 hours.  Vac stables at 1.78e-7 Torr.

Cooling down at 2A/min

 Wednesday, May 04, 2016, 13:28

Target boat has a layer of niobium foil on the bottom of the boat.

A niobium foil has been made with slots to hold samples [similar to when sintering endcaps] *See attached photos

Larger niobium samples are placed in the slots, holding in place, to avoid warping; smaller niobium sample sitting inside the boat by itself.

Smaller sample closest to OMEGA IR reading [right side]

Boat is wrapped with 1 large layer of Ta foil, wrapped around the boat 3x, careful to avoid touching samples.

Loaded into evap2 yesterday.

Vacuum pump bearings gone - pump replaced this morning by vacuum group.

Pumping down now...

 Friday, May 06, 2016, 13:36

HS water valves opened, no leaks detected.

Tapped up manually to 35A.

IGP1 = 2.4e-7 Torr

Setting auto-ramp rate at 0.2A/min to 250A over the weekend.

Will tap up manually monday to final desired temperature of 1400C.

 Monday, May 09, 2016, 09:38

OMEGA = 1128C

IGP1 = 1.3e-7 Torr

TGHT = 250A, 3.7V

Tapping up manually to 1400C...

 Monday, May 09, 2016, 14:05

Evap2 has reached ~1405C

TGHT = 341A, 5.34V

IGP1 = 1.9e-7 Torr

Will remain at max setpoints for min 4hrs then initiate cool down.

 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.

Tuesday, April 26, 2016, 13:32

Container coated with TaC using 'flushing technique'.

Wrapped with 3 x Ta heat shields, incl center block - new method of each layer being one long single Ta foil covering entire container incl center block

Currently pumping down in evap2

 Wednesday, April 27, 2016, 10:25

IGP1 = 2.6e-7 Torr.

HS water valves opened, no leaks detected.

Tapped up manually to 35A.

Waited ~35min

Vacuum stable, IGP1 = 6.7e-7 Torr

Initiated auto-ramp at 0.2A/min for the TGHT with a final setpoint of 400A

Final desired temperature = 1900C

 Thursday, April 28, 2016, 14:41

Previously TBHT not on when sintering IGLIS container [since no ionizer tube] - John decided will turn on for this round

Tapped up TBHT manually to 140A, 1.69V

IGP1 = 4.5e-7 Torr

OMEGA = 1635C

TGHT = 382A, 5.8V

Initiating auto-ramp of TBHT at 0.1A/min with a final setpoint of 230A.

Friday, April 29, 2016, 08:40

IGP1 = 2.22-7 Torr

TGHT = 400A, 6.1V

TBHT = 233A, 2.9V

OMEGA = 1719C

Tapping up manually to OMEGA = 1900C

Friday, April 29, 2016, 15:22

IGP1 = 3.0e-7 Torr

TGHT = 460A, 7.52V

TBHT =230A, 2.93V

OMEGA = 1904C

Target container has remained at max temperature setpoint of 1900C for 4.5hrs.

Initiating auto cool for TGHT and TBHT at 2.0A/min and 1.0A/min respectively.

 Monday, May 02, 2016, 08:35

Vented in air and opened up this morning.

Container looks good.

See attached photos.