John Wong wrote:

Laura Lambert wrote: John Wong wrote: Laura Lambert wrote:  Thursday, September 15, 2016, 16:23 Target container contains 487 discs of SiC  Target packed length = 16cm.  Mass of SiC(green)  = 58.8795g Container is wrapped with 1x heatshield around each side of cooling fins; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C Chamber is currently being pumped down.   Friday, September 16, 2016, 10:50 Tapped up manually to 50A Waited ~1hr , vacuum stable. IGP1 = 1.24e-5 Torr Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. TGHT max = 500A.  TBHT max at 230A.  Slope on OMEGA = 1.15  Monday, September 19, 2016, 10:53 OMEGA = 1230C TGHT = 360A, 4.75V TBHT = 204A, 2.68V IGP1 = 5.3e-6 Torr Increasing ramping rate to 1.0A/min and 0.5A/min for the TGHT and TBHT respectively.  Monday, September 19, 2016, 11:57 OMEGA = ~1300C TBHT = 230A, 3.16V TGHT = 409A, 5.55V Lowering ramping rate to 0.2A/min while vaccum high IGP1 = 3.05e-5 Torr  Monday, September 19, 2016, 13:22 OMEGA = 1350C TGHT = 425A, 5.82V IGP1 = 1.97e-5 Torr Stepping ramping rate back up to 1.0A/min    Monday, September 19, 2016, 18:24 Measuring the temperature on the SiC is difficult due to the changing in emissivity as the temperature goes up.  So, I will use the MIKRON to measure the temperature on the Ta surface near the end of the tube and OMEGA for measuring the inside.   Using the analogue pyrometer, the temperature on the Ta surface at the end of the tube was measured at around ~1450C; this temperature match the temperature on the Mikron at slope 0.98 (as usual).  To match it with OMEGA, I changed the slope to 1.04 since this measurement is taking readings on the  inside of the tube and on the SiC material.    Note:  The measurements are NOT the absolute temperature.  These are relative temperature measurements  which give some guideline where the target current should be at for the sintering process.  Please plot the temp vs current as the TGHT is being ramped up.  At some point, the windows will get coated and the measurement is no longer reliable.   The plot will be used to give an estimation of the current for 1800C.        Tuesday, September 20, 2016, 15:18 there was a temperature fluctuation resulting in the MIKRON no longer matching the readout on the OMEGA this prompted another change in the slope on the OMEGA to 1.08 TGHT was then tapped up manually to 600A/ 1800C will remain at this max setpoint for a few days before ramping down see attachment for raw data  Wednesday, September 21, 2016, 11:34 temperatures dropped a small amount overnight. tapped up manually to 625A/ 1810C still no coating on window. see attachment for updated raw data    Thursday, September 22, 2016, 12:07 Temperature reader on OMEGA dropped slightly to 1785C overnight.  The temperature on the leg remained at 1800C (MIKRON).  No coating on windows.   Increased TGHT to 635A/10.12V (local 10.40V).  OMEGA reads 1800C, MIKRON ~1817C.   Continue to monitor… (see dropbox for captured photos)

 Monday, September 26, 2016, 13:24

Temperature decreased over weekend.

MIKRON dropped from ~1800C to ~1670C, OMEGA on right side remained ~1800C

Comparing screen shots of temperature readings and camera looking at target from left side, changes can be seen:

-darker area on top edge of target tube, above inside tube, grows larger when temperature drops - indicating 'cooler area' has grown

-initially darker area covers top above target materials on tube, when drops to ~1670C darker area extends down sides of target tube and reaches past target material area

See attached picture showing these details

Target has remained at this max setpoint for ~4-5 days

Windows remain un-coated.

Current and voltage readings remain un-changed.

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

 Wednesday, September 28, 2016, 17:05

Vented in air, target taken out today.

Target looks good!

A small amount of material was removed from the windows in evap2, very thin layer of coating.

Will update tomorrow with photos

Endcaps inserted.

 Tuesday, June 17, 2014, 13:11

Target container is coated with TaC.

Container is wrapped with 3x Ta-heat shields.

Currently being pumped down.

For sintering process:

TGHT and TBHT will be ramped up to 820A and 300A respectively at 0.1A/min

 Tuesday, June 17, 2014, 14:22

HS water cooling valves opened, no leaks detected.

IGP1 @1.8e-6 Torr

TGHT max = 820A/ 17V

TBHT max = 300A/ 5V

Stepped up manually to 40A, waited ~20min, vacuum stable.

Initiating auto-ramp @ 1.0A/min

 Wednesday, June 18, 2014, 11:24

TGHT and TBHT reached their respective 820A and 300A last night.

Internal temp measured from side of EVAP2 with mikron = 1830C

IGP1 = 7.6e-7 Torr

Initiating auto-cool down process at 2.0A/min and 1.0A/min for TGHT and TBHT respectively

vented and opened this morning.

smooth run

 Friday, June 20, 2014, 11:14

Made from batch's: oct 23/2013, oct 31/2013 and june 2012

Total number of foils: 515 discs

Total mass of materials [incl graphite foils]: 64.7224g

Total length packed: 17.8cm

Container is wrapped with 3x Ta-heat shields.

Currently being pumped down.

 Friday, June 20, 2014, 14:56

HS cooling water valves opened, no leaks detected.

IGP1 = 6.2e-6 Torr

TGHT max = 820A/ 17V

TBHT max = 300A/ 5V

Stepping up manually to 40A

 Friday, June 20, 2014, 16:04

IGP1 = 8e-6 Torr

Slowly stepped up to 35A manually.

Vacuum has stabilized.

Initiating auto-ramp at 0.1A/min

Laura Lambert wrote:

Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min

 Friday, June 20, 2014, 16:16

Changing the heating current... 

From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process. 

For this process,

TGHT will ramp up to 600A and TBHT to 230A over the weekend. 

Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C. 

John Wong wrote:

Laura Lambert wrote:  Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min    Friday, June 20, 2014, 16:16 Changing the heating current...  From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process.  For this process, TGHT will ramp up to 600A and TBHT to 230A over the weekend.  Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C.

 Monday, June 23, 2014, 09:45

IGP1 = 5e-6 Torr

TGHT and TBHT are at ~200A

Increasing ramping rate to 0.2A/min

 Monday, June 23, 2014, 11:19

IGP1 = 6.9e-6 Torr

Increasing ramping rate to 2.0A/min

Monday, June 23, 2014, 12:09

JW:  Pressure went up too fast... lower the TGHT ramping up rate to 1A/min.

 Tuesday, June 24, 2014, 16:06

Increasing current with respect to temperature: See attached table

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote:  Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min    Friday, June 20, 2014, 16:16 Changing the heating current...  From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process.  For this process, TGHT will ramp up to 600A and TBHT to 230A over the weekend.  Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C.     Monday, June 23, 2014, 09:45 IGP1 = 5e-6 Torr TGHT and TBHT are at ~200A Increasing ramping rate to 0.2A/min  Monday, June 23, 2014, 11:19 IGP1 = 6.9e-6 Torr Increasing ramping rate to 2.0A/min Monday, June 23, 2014, 12:09 JW:  Pressure went up too fast... lower the TGHT ramping up rate to 1A/min.  Tuesday, June 24, 2014, 16:06 Increasing current with respect to temperature: See attached table

 Tuesday, June 24, 2014, 23:44

Target has been heated at 600A.  Local temperature measured on the right leg = 1814C. 

RGA/ striptool/temperature data can be found on this link: 

https://www.dropbox.com/sh/69memvh6fthodoz/AABZiSKAR9njhbqO4sBATVbla

Something interesting was observed about the out gassing of this target - the right window was coated when the temperature rose above 1500C (on the right end, could be hotter inside?) - see attachment.

I suspect this is Si vapour deposited on the window when the target heater got closed to the sintering temperature for SiC (1800 - 2000C).  

Once the chamber is vented, the coated window will be inspected and analyzed.  More details later...  

Initiate auto-cooling (slow cool down)  TGHT 1A/min; TBHT 0.5/min.  Chamber should be able for venting tomorrow afternoon.  

 Thursday, October 23, 2014, 15:34

*See elog #142 for target description*

one endcap still in place, one removed for OMEGA-IR2C beam to reach material [see pic]

no heat shields

currently being pumped down

 Friday, October 24, 2014, 11:34

EVAP2 pumped down overnight.

IGP1 = 7e-7 Torr

HS water valves opened, no leaks detected.

TGHT will be ramped up to 1400C

TBHT will be ramped up to 230A

 Friday, October 24, 2014, 14:32

TBHT reached 230A, TGHT reached 1400C

Stepped TGHT up manually to 1600C; TGHT = 693A, 10.6V [see pic]

 Friday, October 24, 2014, 15:58

TGHT = 760A, 12.07V [local read back] = setpoint.

epics readback TGHT = 754.8A, 11.76V

OMEGA = 1700C

Friday, October 24, 2014, 16:26

OMEGA = 1800C

epics readback TGHT = 828.7A, 13.15V

Friday, October 24, 2014, 16:34

OMEGA = 1900C

epics readback TGHT = 899A, 14.53V

Friday, October 24, 2014, 16:46

OMEGA = 2000C

epics readback TGHT = 967A, 15.8V

MIKRON target spot on SiC = 1650C, e = 0.97

Laura Lambert wrote:

Thursday, October 23, 2014, 15:34 *See elog #142 for target description* one endcap still in place, one removed for OMEGA-IR2C beam to reach material [see pic] no heat shields currently being pumped down  Friday, October 24, 2014, 11:34 EVAP2 pumped down overnight. IGP1 = 7e-7 Torr HS water valves opened, no leaks detected. TGHT will be ramped up to 1400C TBHT will be ramped up to 230A  Friday, October 24, 2014, 14:32 TBHT reached 230A, TGHT reached 1400C Stepped TGHT up manually to 1600C; TGHT = 693A, 10.6V [see pic]  Friday, October 24, 2014, 15:58 TGHT = 760A, 12.07V [local read back] = setpoint. epics readback TGHT = 754.8A, 11.76V OMEGA = 1700C Friday, October 24, 2014, 16:26 OMEGA = 1800C epics readback TGHT = 828.7A, 13.15V Friday, October 24, 2014, 16:34 OMEGA = 1900C epics readback TGHT = 899A, 14.53V Friday, October 24, 2014, 16:46 OMEGA = 2000C epics readback TGHT = 967A, 15.8V MIKRON target spot on SiC = 1650C, e = 0.97

 Tuesday, November 04, 2014, 15:59

Target was heated up to 2000C and last for about 1.5 days before the right leg (ionizer points into the page) broke off. 

Interesting discovery...  The "yellowish" crystals are forming on the discs. 

Suspecting a phase transformation of 6H (hexagonal/- alpha SiC (hexagonal) polytype to 3C(cubic) - beta SiC

More study needs to be done... 

See elog # 168.

The leg of this target was repaired in the Machine shop. 

THIS TARGET WILL NOT BE USED ONLINE -  IT WILL BE USED FOR OFFLINE R&D PURPOSES.

Thursday, August 08, 2013, 15:19

NiO target materials loaded into the container yesterday.

Total discs = 530, (5 discs/pack)

length [after loaded] = 9.0cm

Target container is wrapped with Ta-heat shields, and will be removed after sintering process.

No end caps were inserted.

The chamber has been pumped down and currently IG1 = 3.8x10-06 Torr.

The HS cooling water was turned on and no leaks were detected.

TGHT and TBHT have been stepped up to 50A.

Auto-ramping setting:

0.2A/min for TGHT max = 250A, TBHT max = 230A.

Good vacuum = 3.00e-05 Torr

Bad vacuum = 4.00e-05 Torr

**See attachment #1 for pictures of target pre-sintering

Laura Lambert wrote:

Thursday, August 08, 2013, 15:19 NiO target materials loaded into the container yesterday. Total discs = 530, (5 discs/pack) length [after loaded] = 9.0cm Target container is wrapped with Ta-heat shields, and will be removed after sintering process. No end caps were inserted. The chamber has been pumped down and currently IG1 = 3.8x10-06 Torr. The HS cooling water was turned on and no leaks were detected. TGHT and TBHT have been stepped up to 50A. Auto-ramping setting: 0.2A/min for TGHT max = 250A, TBHT max = 230A. Good vacuum = 3.00e-05 Torr Bad vacuum = 4.00e-05 Torr **See attachment #1 for pictures of target pre-sintering

 Thursday, August 08, 2013, 17:26

Pressure is stabilizing at ~2.2e-5 Torr.  TGHT/TBHT at 50A.

Initiated auto-ramping... 

Sunday, August 11, 2013, 21:30  

TGHT/TBHT have reached to 250A/230A.  Target have been heated over the weekend.  

Cooling down initiated; 2A/min.  

The chamber wil be vented in air tomorrow. 

 Monday, August 12, 2013, 18:01

The sinterring process is complete. 

The target is ready to be removed from the evaporator, and the endcaps will be inserted.

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. 

 Friday, December 16, 2016, 14:08

Target consists of 470 discs.

Total packed length 3.4cm [exactly 7.8cm space on both sides]

Total mass 45.9091g [Incl foils + Ta wire on 6 packs]

Target consists of 350 single discs and 6x20 packs of Ta discs

Discs in target are arranged as follows: 1pack / 75singles / 1pack / 100singles / 2packs / 100singles / 1pack / 75singles / 1pack

3x Ta Heat shields.

LP-FEBIAD container with large center block.

No endcaps inserted, no Rh foil inserted.

Chamber currently pumping down.

TBHT will be ramped up to 230A at 1.0A/min.

TGHT will be ramped up to 350A at 2.0A/min.

Final desired temperature = 1900C

 Friday, December 16, 2016, 14:32

 Monday, December 19, 2016, 11:52

Tapped up manually to ~1900C [see attached excel for details on data collected - interesting temperature fluctuations]

 Will remain at max setpoints for min 4hrs then auto-cool

 Monday, December 19, 2016, 15:20

Target has remained at max setpoints for just over 4hrs

TGHT = 520A, 8.67V

OMEGA = 1820C

IGP1 = 5.2e-7 Torr

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

 Tuesday, December 20, 2016, 11:52

Vented in air and opened up this morning.

Looks like the windows was coated in evap2, unsure if this was missed and coated before conditioning target or if this is from materials coming out during conditioning process...

Target looks good.

Endcaps inserted but not expanded.

 Wednesday, November 29, 2017, 16:17

LP-FEBIAD loaded into evap2 today and currently pumping down.

Temperature measurements of the ionizer will be done by Fernando for ARIEL development.

Ta foil covering side holes on heat shield so no temp measurements can be done using OMEGA on side ports of evaporator as per request of Fernando

No Ta heat shields on container.

Final desired temperature of ionizer = 2000C

 Thursday, November 30, 2017, 09:51

HS water valves opened, no leaks detected.

IGP1 = 2.1e-7 Torr

IGP2 = 1.7e-7 Torr

Tapped up to TGHT = 350A, 5.83V; TBHT = 230A, 3.31V

IGP1 = 6.3e-7 Torr

IGP2 = 3.7e-7 Torr

Will check temp measurements in lab after lunch before proceeding...

 Friday, December 01, 2017, 11:04

Temperature measurements done.

Initiated auto-cool this morning.

TGHT cooling at 2.0A/min and TBHT at 1.0A/min.

Monday, December 04, 2017, 11:04

Removed from evap2 this morning.

 Wednesday, December 13, 2017, 10:36

LP-FEBIAD loaded into evap2 this morning and pumped down.

Temperature measurements of the ionizer will be done by Fernando for ARIEL development.

Ta foil covering side holes on heat shield so no temp measurements can be done using OMEGA on side ports of evaporator as per request of Fernando

No Ta heat shields on container.

HS water valves opened, no leaks detected.

IGP1 = 2.3e-6 Torr

IGP2 = 1.7e-6 Torr

Tapped up to TGHT = 50A, 0.30V; TBHT = 50A, 0.59V

IGP1 = 1.8e-6 Torr

IGP2 = 1.4e-6 Torr

Initiating auto ramp for TGHT at 2.0A/min up to 350A and TBHT at 1.0A/min up to 210A

 Wednesday, December 13, 2017, 14:53

IGP1 = 7.6e-7 Torr

IGP2 = 6.4e-7 Torr

TGHT = 350A, 5.85V

TBHT = 210A, 3.02V

TGHT and TBHT will be adjusted accordingly for temperature measurements...

Thursday, December 14, 2017, 09:16 

IGP1 = 2.1e-7 Torr

IGP2 = 1.7e-7 Torr

TGHT = 385A, 6.80V

TBHT = 210A, 3.01V

Tapped up to TGHT = 400A, 7.11V

Stopped for temperature measurements.

Tapped up to TGHT = 450A, 8.20V

 Friday, December 15, 2017, 09:50

IGP1 = 1.2e-7 Torr

IGP2 = 9.6e-8 Torr

TGHT = 350A, 5.82V

TBHT = 210A, 2.94V

Initiating auto-ramp to TGHT = 650A

Monday, December 18, 2017, 10:43

Temperature measurements done.

Initiated auto-cool.

TGHT cooling at 2.0A/min and TBHT at 1.0A/min.

 Tuesday, December 19, 2017, 11:40

Vented in air and removed from evap2 today.

Monday, February 19, 2018, 13:39

LP-FEBIAD loaded into evap2 this morning and pumped down.

Temperature measurements of the ionizer will be done by Fernando for ARIEL development.

Ta foil covering side holes on heat shield so no temp measurements can be done using OMEGA on side ports of evaporator as per request of Fernando

No Ta heat shields on container.

HS water valves opened, no leaks detected.

IGP1 = 2.75e-6 Torr

IGP2 = 1.42e-6 Torr

Tapped up to TGHT = 50A, 0.53V; TBHT = 50A, 0.56V

IGP1 = 2.64e-6 Torr

IGP2 = 1.35e-6 Torr

Initiating auto ramp for TGHT at 2.0A/min up to 350A and TBHT at 1.0A/min up to 210A

 Tuesday, February 20, 2018, 09:15

IGP1 = 6.9e-7 Torr

IGP2 = 3.8e-7 Torr

TGHT = 350A, 5.98V

TBHT = 210A, 3.02V

TGHT and TBHT will be adjusted accordingly for temperature measurements...

 Tuesday, February 27, 2018, 14:55

Temperature measurements done.

Initiated auto-cool.

TGHT cooling at 2.0A/min and TBHT at 1.0A/min.

 Wednesday, February 28, 2018, 10:39

Tuesday, December 19, 2017, 11:40

Vented in air and removed from evap2 today.