Laura Lambert wrote:

Friday, April 17, 2015, 16:01 Total number of foils: 520 discs Total mass of materials [incl graphite foils]: 60.2441g Total length packed: 17.0cm Container is wrapped with 3x Ta-heat shields. No endcaps inserted to allow outgasing. Currently being pumped down.  Monday, April 20, 2015, 11:08 Target container is coated with TaC and wrapped with 3-Ta heat shields, not incl center block. TGHT and TBHT will be ramped up to 820A and 230A, respectively. Chamber pumped down over the weekend. IGP1 = 2.1e-7 Torr. HS cooling water valves opened; no leaks detected. TGHT max voltage = 18V, TBHT max voltage = 5V .... attempted to start stepping up manually. power supply not responding to epics controls for TBHT only...looking into problems now...  Monday, April 20, 2015, 16:06 Epics is working. Power supply connections unplugged/plugged back in. Everything working again. Tapped up manually to 40A. Waited ~1hr30 for vacuum to stabilize. IGP1 = 1.8e-6 Torr. Good vac = 3e-5 Torr. Bad vac = 4e-5 Torr. TGHT and TBHT will be ramped up to 820A and 230A, respectively. Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively.  Wednesday, April 22, 2015, 15:23 TGHT = 200A, 2.26V; TBHT = 117A, 1.58V IGP1 = 9.8e-6 Torr. Increasing auto-ramp to 0.4A/min and 0.2A/min for the TGHT and TBHT respectively.

 Thursday, April 23, 2015, 10:15

Vac at 2.e-6 Torr.  Increased TGHT ramping rate to 1.0A/min.  Current temperature at 1443C, TGHT at 641A, TBHT at 230A.

 Thursday, April 23, 2015, 15:02

Evap#2 window for the temp reader is now coated, so temp reading is not available.  (see attachment). 

TGHT has been at 820A/13.45V for almost 2 hours, will continue to heat at this current for a few more hours.  Will initiate the cooling process from home…  

 Thursday, April 23, 2015, 22:31

Target has been heated at 820A for about 9.5hrs.  Current vacuum at 4.7e-7 Torr.

Initiating cooling process at -2A/min for TGHT and -1A/min for TBHT.

Friday, April 24, 2015, 10:13  

Target has been cooled at 0A for about 5 hours.  Chamber is currently being vented and the target will be taken out for inspection.

Friday, April 24, 2015, 12:37  

The target was inspected.  

Some yellow crystals were form around the ends but they were easily removed this time.  

With both ends open during the sintering process and shorten the target length with 1cm space of both side, the target is looking a lot better.  

 No visible damage on the target surface.  

Inside, the channel has a clear pathway, and the discs are nicely aligned.  

End caps and Rh foils are inserted - It's ready for assembly.

See link for pics after the sintering process.

https://www.dropbox.com/sh/w5k4l3fezfat2cm/AAAyX67zyUPUVvN_WzEHFXM2a?dl=0

Tuesday, June 23, 2015, 12:21

Target container is loaded with 485 discs of SiC with packed length of 17.4cm. 

Container is wrapped with 3 Ta-heat shields and previously coated/sintered with TaC.

Chamber is currently being pumped down

TGHT will be ramped up to 800A, ~1800C, and TBHT is limited to 230A max.

 Tuesday, June 23, 2015, 15:53

HS valves are open, no leaks detected.

TGHT stepped up to 70A, pressure is currently at 4.17e-5 torr and coming up. 

Initiated auto-ramping at 0.5A/min for both TGHT and TBHT: good vac at 3.0e-5, bad vac at 4.0e-5 Torr.

 Wednesday, June 24, 2015, 00:03

Stopped auto-ramping about 2 hours ago.  

Manual stepped up TGHT to 73A.  Vac is stabilizing at 5e-8 Torr.  Will keep it at that current over night.

 Wednesday, June 24, 2015, 07:41

Vac has come down to 3.6e-6 Torr.

Continue to step up TGHT...

 Wednesday, June 24, 2015, 23:52

It has been a super long day operating the evaporator and finally the target is up to 1800C.  Vac is coming down from 2.e-5 Torr. 

TGHT is at 790A/12.61V, DV at 6.60V, TBHT at 230A/3.57V.  Omega temp reader is at 1680C - that's due to the window being coated with SiC, as expected. 

Target will continue heated at that current for over night, and will start the cooling process next AM. 

Thursday, June 25, 2015, 06:18  

Target is holding pretty well over night.  Vac is coming down to 1.6e-6 Torr. 

Initiated cooling down at 2A/min. 

John Wong wrote:

Tuesday, June 23, 2015, 12:21 Target container is loaded with 485 discs of SiC with packed length of 17.4cm.  Container is wrapped with 3 Ta-heat shields and previously coated/sintered with TaC. Chamber is currently being pumped down TGHT will be ramped up to 800A, ~1800C, and TBHT is limited to 230A max.  Tuesday, June 23, 2015, 15:53 HS valves are open, no leaks detected. TGHT stepped up to 70A, pressure is currently at 4.17e-5 torr and coming up.  Initiated auto-ramping at 0.5A/min for both TGHT and TBHT: good vac at 3.0e-5, bad vac at 4.0e-5 Torr.  Wednesday, June 24, 2015, 00:03 Stopped auto-ramping about 2 hours ago.   Manual stepped up TGHT to 73A.  Vac is stabilizing at 5e-8 Torr.  Will keep it at that current over night.  Wednesday, June 24, 2015, 07:41 Vac has come down to 3.6e-6 Torr. Continue to step up TGHT...  Wednesday, June 24, 2015, 23:52 It has been a super long day operating the evaporator and finally the target is up to 1800C.  Vac is coming down from 2.e-5 Torr.  TGHT is at 790A/12.61V, DV at 6.60V, TBHT at 230A/3.57V.  Omega temp reader is at 1680C - that's due to the window being coated with SiC, as expected.  Target will continue heated at that current for over night, and will start the cooling process next AM.  Thursday, June 25, 2015, 06:18   Target is holding pretty well over night.  Vac is coming down to 1.6e-6 Torr.  Initiated cooling down at 2A/min.

 Thursday, June 25, 2015, 16:09

Vented in air and took out this afternoon.

Target looks good [see photos]

Window for OMEGA fully coated from outgassing of target materials

Tuesday, September 01, 2015, 17:16

Target container contains 533 discs of SiC with packed length of 17cm. 

Mass of 533 discs SiC(green)  = 57.8979g

Total mass SiC(green) + target container = 1455g

Container is wrapped with 3 heatshields; no end caps are inserted yet.

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

Chamber is currently being pumped down. 

John Wong wrote:

Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.

 Wednesday, September 02, 2015, 09:11

HS water valves opened, no leaks detected.

IGP1 = 1.15e-6 Torr

Tapped up manually to 40A.

Waited ~1hr40 for vacuum to stabilize.

IGP1 = 3.6e-6 Torr.

Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C

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

Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed]

Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up.

If LS port still clean, will continue to ramp up to final desired temperature of 1800C.

 Wednesday, September 02, 2015, 14:23

IGP1 = 4.0e-5 Torr.

Vacuum too high, stopped auto-ramp and tapped down manually.

Dropped TGHT down from 80A to 50A

Dropped TBHT down from 55A to 50A

Wednesday, September 02, 2015, 15:29

Vacuum down to IGP1 = 1.2e-5 Torr.

Re-initiating auto-ramp...

 Tuesday, September 08, 2015, 10:04

IGP1 = 4.5e-7 Torr.

TGHT = 630A, 9.6V

TBHT = 230A, 3.2V

DV = 0.22V

OMEGA RS = 1476C

OMEGA LS = 1450C

see attached photo for screenshot.

will tap up manually with a visual on both window ports...

Laura Lambert wrote:

John Wong wrote: Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.     Wednesday, September 02, 2015, 09:11 HS water valves opened, no leaks detected. IGP1 = 1.15e-6 Torr Tapped up manually to 40A. Waited ~1hr40 for vacuum to stabilize. IGP1 = 3.6e-6 Torr. Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C Initiating auto ramp at a rate of 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed] Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up. If LS port still clean, will continue to ramp up to final desired temperature of 1800C.  Wednesday, September 02, 2015, 14:23 IGP1 = 4.0e-5 Torr. Vacuum too high, stopped auto-ramp and tapped down manually. Dropped TGHT down from 80A to 50A Dropped TBHT down from 55A to 50A Wednesday, September 02, 2015, 15:29 Vacuum down to IGP1 = 1.2e-5 Torr. Re-initiating auto-ramp...  Tuesday, September 08, 2015, 10:04 IGP1 = 4.5e-7 Torr. TGHT = 630A, 9.6V TBHT = 230A, 3.2V DV = 0.22V OMEGA RS = 1476C OMEGA LS = 1450C see attached photo for screenshot. will tap up manually with a visual on both window ports...

 Tuesday, September 08, 2015, 15:44

TGHT has stepped up to 820A.  Coating on both windows is becoming obvious and it's interfering the temp readers; however, the left window (see attachment, which is further away from the target) is lightly coated than the right.  See attachment for The Temp (and Power) vs current plots.

Target will remained heated at the current and will be cooled down later today. 

The target will be re-conditioned up to 820A and temp and mass will be re-measured.

Plans:

The chamber will be vented tomorrow and the target will be taken out to weigh for mass change. 

The chamber windows will need to be clean.

A piece of Ta foil will be cover in front of the ionizer to trap any loss material (if any).

 Tuesday, September 08, 2015, 17:37

TGHT was at 800A for 2 hours before ramping up 820A for another 2 hours heating.  More coating on the right window is observed and temp reading came down to 1340C.  The left window remains the same and temp reads at 1646C.  

Ramping TGHT/TBHT to 0A at 2A/min and 1A/min, respectively.  

 Wednesday, September 09, 2015, 12:27

Result after the sintering process:

No yellow crystal formed (compared to previously observed SiC targets that heated up above 1900C). 

Total green mass = 57.90g 

mass of graphite foil = 0.035g x 533 discs = 18.7g 

mass of green SiC = 39.30g 

Target container with SiC before sintered = 1455g 

Target container after sintered = 1450g 

mass loss ~ 5.0g ~ 13% organic mass, as expected!  

The target will undergo the re-condition stage, and the temperature will be measured from 600A to 820A. 

John Wong wrote:

Laura Lambert wrote: John Wong wrote: Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.     Wednesday, September 02, 2015, 09:11 HS water valves opened, no leaks detected. IGP1 = 1.15e-6 Torr Tapped up manually to 40A. Waited ~1hr40 for vacuum to stabilize. IGP1 = 3.6e-6 Torr. Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C Initiating auto ramp at a rate of 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed] Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up. If LS port still clean, will continue to ramp up to final desired temperature of 1800C.  Wednesday, September 02, 2015, 14:23 IGP1 = 4.0e-5 Torr. Vacuum too high, stopped auto-ramp and tapped down manually. Dropped TGHT down from 80A to 50A Dropped TBHT down from 55A to 50A Wednesday, September 02, 2015, 15:29 Vacuum down to IGP1 = 1.2e-5 Torr. Re-initiating auto-ramp...  Tuesday, September 08, 2015, 10:04 IGP1 = 4.5e-7 Torr. TGHT = 630A, 9.6V TBHT = 230A, 3.2V DV = 0.22V OMEGA RS = 1476C OMEGA LS = 1450C see attached photo for screenshot. will tap up manually with a visual on both window ports...    Tuesday, September 08, 2015, 15:44 TGHT has stepped up to 820A.  Coating on both windows is becoming obvious and it's interfering the temp readers; however, the left window (see attachment, which is further away from the target) is lightly coated than the right.  See attachment for The Temp (and Power) vs current plots. Target will remained heated at the current and will be cooled down later today.    The target will be re-conditioned up to 820A and temp and mass will be re-measured. Plans: The chamber will be vented tomorrow and the target will be taken out to weigh for mass change.  The chamber windows will need to be clean. A piece of Ta foil will be cover in front of the ionizer to trap any loss material (if any).  Tuesday, September 08, 2015, 17:37 TGHT was at 800A for 2 hours before ramping up 820A for another 2 hours heating.  More coating on the right window is observed and temp reading came down to 1340C.  The left window remains the same and temp reads at 1646C.   Ramping TGHT/TBHT to 0A at 2A/min and 1A/min, respectively.    Wednesday, September 09, 2015, 12:27 Result after the sintering process: No yellow crystal formed (compared to previously observed SiC targets that heated up above 1900C).  Total green mass = 57.90g  mass of graphite foil = 0.035g x 533 discs = 18.7g  mass of green SiC = 39.30g  Target container with SiC before sintered = 1455g  Target container after sintered = 1450g  mass loss ~ 5.0g ~ 13% organic mass, as expected!   The target will undergo the re-condition stage, and the temperature will be measured from 600A to 820A.

 Wednesday, September 09, 2015, 17:39

Both end-caps are inserted onto the targets.  The total mass (Target, Sintered SiC, end caps, 4x 19"round graphite foils) = 1453g.

Target is wrapped with 3 layers of heat shields.  

The extraction electrode is wrapped with Ta-foil (see attachment).  This is to trap any lose particle, if any.  

Chamber is currently being pumped down, currently at 1.2e-5 Torr.  

John Wong wrote:

John Wong wrote: Laura Lambert wrote: John Wong wrote: Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.     Wednesday, September 02, 2015, 09:11 HS water valves opened, no leaks detected. IGP1 = 1.15e-6 Torr Tapped up manually to 40A. Waited ~1hr40 for vacuum to stabilize. IGP1 = 3.6e-6 Torr. Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C Initiating auto ramp at a rate of 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed] Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up. If LS port still clean, will continue to ramp up to final desired temperature of 1800C.  Wednesday, September 02, 2015, 14:23 IGP1 = 4.0e-5 Torr. Vacuum too high, stopped auto-ramp and tapped down manually. Dropped TGHT down from 80A to 50A Dropped TBHT down from 55A to 50A Wednesday, September 02, 2015, 15:29 Vacuum down to IGP1 = 1.2e-5 Torr. Re-initiating auto-ramp...  Tuesday, September 08, 2015, 10:04 IGP1 = 4.5e-7 Torr. TGHT = 630A, 9.6V TBHT = 230A, 3.2V DV = 0.22V OMEGA RS = 1476C OMEGA LS = 1450C see attached photo for screenshot. will tap up manually with a visual on both window ports...    Tuesday, September 08, 2015, 15:44 TGHT has stepped up to 820A.  Coating on both windows is becoming obvious and it's interfering the temp readers; however, the left window (see attachment, which is further away from the target) is lightly coated than the right.  See attachment for The Temp (and Power) vs current plots. Target will remained heated at the current and will be cooled down later today.    The target will be re-conditioned up to 820A and temp and mass will be re-measured. Plans: The chamber will be vented tomorrow and the target will be taken out to weigh for mass change.  The chamber windows will need to be clean. A piece of Ta foil will be cover in front of the ionizer to trap any loss material (if any).  Tuesday, September 08, 2015, 17:37 TGHT was at 800A for 2 hours before ramping up 820A for another 2 hours heating.  More coating on the right window is observed and temp reading came down to 1340C.  The left window remains the same and temp reads at 1646C.   Ramping TGHT/TBHT to 0A at 2A/min and 1A/min, respectively.    Wednesday, September 09, 2015, 12:27 Result after the sintering process: No yellow crystal formed (compared to previously observed SiC targets that heated up above 1900C).  Total green mass = 57.90g  mass of graphite foil = 0.035g x 533 discs = 18.7g  mass of green SiC = 39.30g  Target container with SiC before sintered = 1455g  Target container after sintered = 1450g  mass loss ~ 5.0g ~ 13% organic mass, as expected!   The target will undergo the re-condition stage, and the temperature will be measured from 600A to 820A.     Wednesday, September 09, 2015, 17:39 Both end-caps are inserted onto the targets.  The total mass (Target, Sintered SiC, end caps, 4x 19"round graphite foils) = 1453g. Target is wrapped with 3 layers of heat shields.   The extraction electrode is wrapped with Ta-foil (see attachment).  This is to trap any lose particle, if any.   Chamber is currently being pumped down, currently at 1.2e-5 Torr.

 Thursday, September 10, 2015, 09:55

HS water valves opened this morning, no leaks detected.

TGHT and TBHT tapped up manually to 35A.

IGP1 = 4.4e-7 Torr, vacuum stable.

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

Laura Lambert wrote:

John Wong wrote: John Wong wrote: Laura Lambert wrote: John Wong wrote: Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.     Wednesday, September 02, 2015, 09:11 HS water valves opened, no leaks detected. IGP1 = 1.15e-6 Torr Tapped up manually to 40A. Waited ~1hr40 for vacuum to stabilize. IGP1 = 3.6e-6 Torr. Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C Initiating auto ramp at a rate of 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed] Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up. If LS port still clean, will continue to ramp up to final desired temperature of 1800C.  Wednesday, September 02, 2015, 14:23 IGP1 = 4.0e-5 Torr. Vacuum too high, stopped auto-ramp and tapped down manually. Dropped TGHT down from 80A to 50A Dropped TBHT down from 55A to 50A Wednesday, September 02, 2015, 15:29 Vacuum down to IGP1 = 1.2e-5 Torr. Re-initiating auto-ramp...  Tuesday, September 08, 2015, 10:04 IGP1 = 4.5e-7 Torr. TGHT = 630A, 9.6V TBHT = 230A, 3.2V DV = 0.22V OMEGA RS = 1476C OMEGA LS = 1450C see attached photo for screenshot. will tap up manually with a visual on both window ports...    Tuesday, September 08, 2015, 15:44 TGHT has stepped up to 820A.  Coating on both windows is becoming obvious and it's interfering the temp readers; however, the left window (see attachment, which is further away from the target) is lightly coated than the right.  See attachment for The Temp (and Power) vs current plots. Target will remained heated at the current and will be cooled down later today.    The target will be re-conditioned up to 820A and temp and mass will be re-measured. Plans: The chamber will be vented tomorrow and the target will be taken out to weigh for mass change.  The chamber windows will need to be clean. A piece of Ta foil will be cover in front of the ionizer to trap any loss material (if any).  Tuesday, September 08, 2015, 17:37 TGHT was at 800A for 2 hours before ramping up 820A for another 2 hours heating.  More coating on the right window is observed and temp reading came down to 1340C.  The left window remains the same and temp reads at 1646C.   Ramping TGHT/TBHT to 0A at 2A/min and 1A/min, respectively.    Wednesday, September 09, 2015, 12:27 Result after the sintering process: No yellow crystal formed (compared to previously observed SiC targets that heated up above 1900C).  Total green mass = 57.90g  mass of graphite foil = 0.035g x 533 discs = 18.7g  mass of green SiC = 39.30g  Target container with SiC before sintered = 1455g  Target container after sintered = 1450g  mass loss ~ 5.0g ~ 13% organic mass, as expected!   The target will undergo the re-condition stage, and the temperature will be measured from 600A to 820A.     Wednesday, September 09, 2015, 17:39 Both end-caps are inserted onto the targets.  The total mass (Target, Sintered SiC, end caps, 4x 19"round graphite foils) = 1453g. Target is wrapped with 3 layers of heat shields.   The extraction electrode is wrapped with Ta-foil (see attachment).  This is to trap any lose particle, if any.   Chamber is currently being pumped down, currently at 1.2e-5 Torr.      Thursday, September 10, 2015, 09:55 HS water valves opened this morning, no leaks detected. TGHT and TBHT tapped up manually to 35A. IGP1 = 4.4e-7 Torr, vacuum stable. Initiating auto-ramp at 1.0A/min and 0.5A/min for the TGHT and TBHT respectively with final setpoints of 600A and 230A.

Thursday, September 10, 2015, 12:05  

Changed TGHT to 2A/min and TGHT remains at 1A/min.  Vacuum is table at 1.0e-6 Torr. 

Friday, September 11, 2015, 11:34  

TGHT was at 600A for almost 20 hours.  Vac at 5.2 e-7 Torr.   L-temp at 1490C, R-temp at 1685 (odd?).   Using pyrometer to measure - Right end does seem brighter than the L end.  

Continue to ramp up TGHT.  Date is collected, will be posted later.  

 Friday, September 11, 2015, 11:53

L/R-temp measurements just don't seem normal.  

Ramped up to 220A- temp reads L = 1522C, R = 1722C.  

Ramping down TBHT doesn't change the temp.  

Will cool TGHT/TBHT to 0A at 2A/min & 1A/min, respectively.  

Will vent the chamber on Monday and inspect for any wrong.

 Monday, September 14, 2015, 12:13

The target has taken out for inspection.  No visible damage/problem was observed.  The Ta-foil for loss particle capture only showed some heat marking but no material was trapped. 

Target was weighted, no mass loss was observed.

Try expending the end caps to get a good thermal conductivity and will re-conditiong again.  

 Tuesday, September 15, 2015, 12:31

The end caps have been expended. 

New Ta foils are used for the heat shields.  The foils are cut in 3 1/4" x 12" and wrapped around the target.  (see attachment).  This is to see if the heat is evenly distributed.  

Both omega optical lens are aligned properly.  

Target is installed but the chamber is NOT yet being pumped down.  Awaiting for the fume hood work in B2 level to be complete before the evaporator can be started. 

 Wednesday, September 16, 2015, 17:57

The work in the B2 level is done; the nuclear ventilation for the evaporators is now operational. 

Chamber is currently being pumped down.

 Thursday, September 17, 2015, 12:19

Chamber has been pump down overnight and pressure is currently at 5.8e-7 Torr.

HS valves are opened and no leaks are detected.

Ramping up TGHT/TBHT to 600A at 2A/min and 230A at 1A/min, respectively.

 Thursday, September 17, 2015, 17:58

TGHT has reached to 600A/9.14V.  Both the L and R temperatures are measured at 1710C and 1760C, respectively.  At 600A, the temperature now is about 300C higher compared to that during the sintering process. 

The difference in the temperature could be from Ta surface vs SiC surface.  (But the 2-color IR temp reader shouldn't matter what color it's measuring?!! I don't know!)

Note: 

Both temperature readings are fairly close.  Could this be improved from the new Ta-foils?  Possible!

It is still unclear what is the absolute temperature.  A more systematic student needs to be done. 

Using a thermocouple couple to measurement the endcaps at 600A and compared with the Omage reader may help to understand more. 

After discussing with Friedhelm, it is decided to stay the target at 600A for the conditioning process. 

 Friday, September 18, 2015, 09:10

Target has been heated at 600A at stable temperature at 1716C (LS) and 1769C (RS), see attachment. 

 Friday, September 18, 2015, 11:45

Initiated cooling down at 2A/min for TGHT, and 1A/min TBHT. 

Currently vac at 5.48e-7 Torr.

 Thursday, September 24, 2015, 11:31

Target was inspected after the 2nd conditioning, up to 1700C at 600A for overnight. 

No solid particle was observed that might have extracted from the ionizer tube.  

The heat shields have been removed and the target is ready for assembly. 

 Tuesday, November 10, 2015, 14:20

Container previously sintered with TaC coating and temperature measurements taken [see elog ID# 256, 257, 258]

3x Ta heat shields

2 packs of 5 SiC discs ~2inches from the end of the right side wrt ionizer tube into page.

Loaded into evap2 and currently pumping down.

see photos attached.

 Monday, November 16, 2015, 11:24

HS water valves opened up this morning, no leaks detected.

Tapped up manually to 35A.

Vacuum stable.

IGP1 = 3.4e-7 Torr.

Initiating auto-ramp at 1.0A/min and 0.5A/min for the TGHT and TBHT respectively.

Final setpoints: 250A for the TGHT and 230A for the TBHT

Monday, November 16, 2015, 13:29

Vacuum too high.

IGP1 = 2.9e-5 Torr.

Decreasing ramping rate down to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.

 Tuesday, November 17, 2015, 09:12

IGP1 = 1.45e-7 Torr.

TGHT = 250A, 3.28V

TBHT = 230A, 3.33V

OMEGA = 1194C

Tapping up manually to 1900C

 Tuesday, November 17, 2015, 11:22

Tapped up manually to 1800C, realized SiC should only be tapped up to 1700C, backed off immediately down to 415A from 460A/ 1800C.

See attachment for photo of striptool/ time spent above 1700C [~20min].

 Tuesday, November 17, 2015, 15:46

TGHT remained at 1700C for ~4hrs.

TGHT = 420A, 6.44V.

IGP1 = 2.3e-7 Torr.

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

See attachment for raw data of temperature measurements.

 Wednesday, November 18, 2015, 13:32

Vented in air and took out this morning.

Looks good, no visual changes with the container.

Monday, January 11, 2016, 15:25

Small center block LP-SIS container previously sintered with TaC coating

3x Ta heat shields

Container is loaded with 260 discs of SiC with a total length of 8.5cm

Loaded into evap2 and pumped down this morning

HS water valves opened up, no leaks detected

Tapped up manually to 30A

Vacuum stable

IGP1 = 1e-6 Torr

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

Final setpoints: 400A for the TGHT and 230A for the TBHT

Final desired temperature: 1700C

 Tuesday, January 12, 2016, 12:55

TGHT = 138A, TBHT = 80A

IGP1 =  7.7e-6 Torr.

Vacuum stable and coming down.

Increasing ramping rate to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.

 Wednesday, January 13, 2016, 09:32

TGHT reached 400A ~11.5hrs ago

TBHT reached 230A ~8hrs ago

OMEGA = 1400C

IGP1 = 1.75e-7 Torr

Tapping up manually to 1700C...

 Wednesday, January 13, 2016, 10:14

Previous temperature measurement of OMEGA = 1400C is wrong due to window port being coated with SiC [see attached photos]

Will remain at TGHT = 420A for 4hrs then cool down this afternoon

Wednesday, January 13, 2016, 14:29

Remained at max setpoints for 4.5hrs.

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

 Thursday, January 14, 2016, 09:47

Vented in air and opened up this morning

Target looks good

Will insert and expand endcaps this afternoon

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

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... 

 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.

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.

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.