Thursday, May 28, 2015, 11:34

Endcaps were sintered [see elog#199]

A Ta foil is placed in the target boat with separate slots for each endcap [see image]

The target boat is wrapped with 3-layers of Ta-heat shield.

The boat is installed in EVAP2, chamber is currently being pumped down.

 Thursday, May 28, 2015, 14:01

HS water valves opened, no leaks detected.

IGP1 = 1.4e-6 Torr.

Initiating manual tap up.

 Thursday, May 28, 2015, 15:10

Manually tapped up TGHT  to 108A, 1.1V

Initiating auto-ramp at 2.0A/min with a max setpoint of 300A

 Thursday, May 28, 2015, 15:22

Hoping to speed up the process...

IGP1 = 1.0e-6 Torr.

Increasing ramping rate to 4.0A/min with a max setpoint of 500A

Final desired temperature = 1800C

Laura Lambert wrote:

Thursday, May 28, 2015, 11:34 Endcaps were sintered [see elog#199] A Ta foil is placed in the target boat with separate slots for each endcap [see image] The target boat is wrapped with 3-layers of Ta-heat shield. The boat is installed in EVAP2, chamber is currently being pumped down.  Thursday, May 28, 2015, 14:01 HS water valves opened, no leaks detected. IGP1 = 1.4e-6 Torr. Initiating manual tap up.  Thursday, May 28, 2015, 15:10 Manually tapped up TGHT  to 108A, 1.1V Initiating auto-ramp at 2.0A/min with a max setpoint of 300A  Thursday, May 28, 2015, 15:22 Hoping to speed up the process... IGP1 = 1.0e-6 Torr. Increasing ramping rate to 4.0A/min with a max setpoint of 500A Final desired temperature = 1800C

 Thursday, May 28, 2015, 17:42

TGHT at 500A. Temp at 1780C.

Increased TGHT to 580A (online operating current),  Temp 1945C, vac 2.9e-6 torr and coming down.  Will remain at that current for the sintering process.

Cooling it down later this evening.

Thursday, May 28, 2015, 21:27  

Temp stabilized at 1960C with TGHT at 580A for almost 4 hours.  Vacuum at 1.8e-7 Torr.

Cooling down initiated at 2A/min.

John Wong wrote:

Laura Lambert wrote:  Thursday, May 28, 2015, 11:34 Endcaps were sintered [see elog#199] A Ta foil is placed in the target boat with separate slots for each endcap [see image] The target boat is wrapped with 3-layers of Ta-heat shield. The boat is installed in EVAP2, chamber is currently being pumped down.  Thursday, May 28, 2015, 14:01 HS water valves opened, no leaks detected. IGP1 = 1.4e-6 Torr. Initiating manual tap up.  Thursday, May 28, 2015, 15:10 Manually tapped up TGHT  to 108A, 1.1V Initiating auto-ramp at 2.0A/min with a max setpoint of 300A  Thursday, May 28, 2015, 15:22 Hoping to speed up the process... IGP1 = 1.0e-6 Torr. Increasing ramping rate to 4.0A/min with a max setpoint of 500A Final desired temperature = 1800C    Thursday, May 28, 2015, 17:42 TGHT at 500A. Temp at 1780C. Increased TGHT to 580A (online operating current),  Temp 1945C, vac 2.9e-6 torr and coming down.  Will remain at that current for the sintering process. Cooling it down later this evening. Thursday, May 28, 2015, 21:27   Temp stabilized at 1960C with TGHT at 580A for almost 4 hours.  Vacuum at 1.8e-7 Torr. Cooling down initiated at 2A/min.

 Friday, May 29, 2015, 11:16

Vented in air and opened up this morning.

Endcaps look great!  

Sintering was spot on [see pictures]

 Monday, July 13, 2015, 11:53

A Ta foil is placed in the target boat with separate slots for each endcap [same as elog 200]

The target boat is wrapped with 3-layers of Ta-heat shield.

The boat is installed in EVAP2, chamber is currently being pumped down.

 Monday, July 13, 2015, 15:00

Opened HS water valves, no leaks detected.

IGP1 = 2.7e-6 Torr.

Tapping up manually.

 Monday, July 13, 2015, 15:41

Tapped up manually to 30A

TGHT = 30A, 0.05V

IGP1 = 7e-6 Torr.

Initiating auto-ramp at 0.2A/min up to 480A with a final desired temperature of 1800C

 Tuesday, July 14, 2015, 09:12

IGP1 = 7.8e-7 Torr

TGHT = 241A, 3.3V

OMEGA = 1010C

Increasing auto-ramp to 2.0A/min

 Tuesday, July 14, 2015, 11:12

Reached final setpoint of TGHT = 480A, 8.43V

OMEGA = 1667C

IGP1 = 3.3e-6 Torr.

Tapping up manually to reach final desired temperature of 1800C.

 Tuesday, July 14, 2015, 11:33

Reached TGHT = 500A, 8.8V by tapping up manually.

OMEGA = 1714V

IGP1= 3.5e-6 Torr.

Re-initiating auto-ramp at 2.0A/min with a final setpoint of 580A.

New final desired temperature min of 1900C

 Tuesday, July 14, 2015, 13:16

TGHT = 577A, 10.74V

OMEGA = 1938C

IGP1 = 3.2e-6 Torr

Endcaps have been at this temperature for just over an hour.

Spikes in vacuum started ~430A - this is due to the green TaC coating reacting with the Ta foil, the carbide is reacting directly with the Ta foil [see picture]

Stopping sintering early before endcaps break -> initiating auto-cool at 2.0A/min.

 Wednesday, July 15, 2015, 11:33

Vented in air and took out this morning.

Endcaps sintered on top side but not fully sintered on inner edge.

Inner edge is peeling off and unsintered green TaC.

The coating peeling off did not shrink, as seen with previous tests done, one would expect a shrinkage in the coating when heated.

The peeling is most likely due to the way to endcaps were placed  in the slots of the Ta foil.

This may have cause the foil to be hotter than the inside of the endcaps and subsequently the Ta foil and TaC coating on the inside reacted - with the Ta foil extracting the carbide from the coating.

This would cause the outer edges of the inside of the endcap to peel/curl inwards as it was heated [like a cast, as the cast dries the outer edges curl inwards].

See photos attached for clarification.

Endcaps will be re-coated and sintered again via a different procedure.

 Thursday, August 06, 2015, 15:36

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

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

There are two separate tubes in the target boat:

1) endcaps coated with TaC coating - never been sintered

2) previously sintered [but not fully] endcaps with a second coating done on the one side of each endcap

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

Chamber is currently being pumped down.

 Friday, August 07, 2015, 08:45

HS water valves opened, no leaks detected.

IGP1 = 3.6e-7 Torr.

Tapped up manually to 30A.

 Friday, August 07, 2015, 11:23

IGP1 = 2.2e-6 Torr.

Vacuum stable.

Initiating auto-ramp at 0.2A/min with a final setpoint of 480A.

Will ramp up over the weekend, confirm temperature readings on monday and tap up to final desired temperature of 1800C manually.

 Friday, August 07, 2015, 13:04

Vacuum climbed quite fast.

IGP1 = 6.3e-6 Torr.

Stopped auto-ramp to allow vacuum to settle.

Waited ~1hr.

IGP1 = 4.3e-6 Torr.

Re-initiating auto-ramp.

 Monday, August 10, 2015, 09:22

TGHT reached 480A, 8.2V on the weekend.

OMEGA = 1708C

IGP1 = 3.8e-7 Torr.

Tapped up manually to 1803C, 520A, 9.0V

IGP1 = 5.9e-7 Torr.

 Monday, August 10, 2015, 14:50

EVAP2 remained at 1800C for 4.5hours.

Internal temperature taken at new window port read 1800C using the mikron.

Initiating auto-cool at 2.0A/min.

 Tuesday, August 11, 2015, 09:23

Vented in air and opened up this morning.

The following observations were noted:

1) single round sintered endcaps:

-Batch of green endcaps, single round of sintering look good. fully sintered.

-however when applying a scratch test, excess TaC scrapes off.

[see single round sintering photos]

-A few endcaps almost heated too long and started to appear brittle/ further crystallization on inside of endcap - the side that did not have a second coating applied.

-Outside of endcap looks good/ fully sintered - the side that had a second round of TaC coating

-further tests confirm this batch should still be okay to use

[see round2 batch photos]

 Friday, February 03, 2017, 14:17

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

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

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

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

Chamber is currently being pumped down.

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

OMEGA slope = 0.98

 Monday, February 06, 2017, 09:29

Power outage this weekend and evap2 tripped off.

Re-pumping down now...

 Tuesday, February 07, 2017, 08:54

HS water valves opened, no leaks detected.

IGP1 = 1.9e-7 Torr

Tapped up manually to 35A

Vacuum stable.

IGP1 = 2.0e-7 Torr

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

Final desired temperature = 1800C

 Wednesday, February 08, 2017, 09:52

IGP1 = 2.98e-7 Torr

TGHT = 325A, 3.5V

Vacuum stable.

Increasing ramping rate to 1.0A/min

 Wednesday, February 08, 2017, 11:46

IGP1 = 6.3e-7 Torr

TGHT = 433A, 4.89V

Increasing max setpoint to TGHT = 500A

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

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

 Wednesday, February 08, 2017, 16:03

IGP1 = 4e-7 Torr

TGHT = 500A, 5.75V

OMEGA still not reading

Initiating auto-cool at -2A/min

Will update elog with more details tomorrow

 Thursday, February 09, 2017, 10:52

Evap2 was cooled down and opened up this morning.

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

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

A lot of power was being lost into the heatshield.

See photos attached of target boat sitting at 500A.

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

Laura Lambert wrote:

Friday, February 03, 2017, 14:17 The endcaps are stacked together with a punched out disc of graphite foil placed in between each endcap for separation so endcaps won't fuse together. The end caps are further wrapped in a larger piece of graphite foil to hold together as a tube [same method used in elogID # 158 and 235] There are also 4 coated springs, 2 on each side of the endcaps tube, with the endcaps tube residing in the middle of the boat. The boat is wrapped with 3-layers of Ta heatshields. Chamber is currently being pumped down. Good vac at 3.0e-5, bad vac at 4.0e-5 Torr. OMEGA slope = 0.98  Monday, February 06, 2017, 09:29 Power outage this weekend and evap2 tripped off. Re-pumping down now...  Tuesday, February 07, 2017, 08:54 HS water valves opened, no leaks detected. IGP1 = 1.9e-7 Torr Tapped up manually to 35A Vacuum stable. IGP1 = 2.0e-7 Torr Initiating auto-ramp at 0.2A/min with a final setpoint of 450A. Final desired temperature = 1800C  Wednesday, February 08, 2017, 09:52 IGP1 = 2.98e-7 Torr TGHT = 325A, 3.5V Vacuum stable. Increasing ramping rate to 1.0A/min  Wednesday, February 08, 2017, 11:46 IGP1 = 6.3e-7 Torr TGHT = 433A, 4.89V Increasing max setpoint to TGHT = 500A OMEGA has still yet to show a temperature...should be reading points at this high in current Will go down to the lab and follow up on OMEGA settings to confirm everything is set up ok before proceeding to a higher current...  Wednesday, February 08, 2017, 16:03 IGP1 = 4e-7 Torr TGHT = 500A, 5.75V OMEGA still not reading Initiating auto-cool at -2A/min Will update elog with more details tomorrow  Thursday, February 09, 2017, 10:52 Evap2 was cooled down and opened up this morning. Turns out both legs on the target boat were touching the new heatshield and therefore had been loosing power. Normally a boat at 500A would read ~1800C, in this scenario at 500A the boat read ~1000C. A lot of power was being lost into the heatshield. See photos attached of target boat sitting at 500A. The heatshield is currently being ground down in those two spots to accommodate the target boat.

 Tuesday, February 14, 2017, 15:43

Heatshield was ground back and target boat now fits nicely into heatshield without contact.

Laura Lambert wrote:

Laura Lambert wrote:  Friday, February 03, 2017, 14:17 The endcaps are stacked together with a punched out disc of graphite foil placed in between each endcap for separation so endcaps won't fuse together. The end caps are further wrapped in a larger piece of graphite foil to hold together as a tube [same method used in elogID # 158 and 235] There are also 4 coated springs, 2 on each side of the endcaps tube, with the endcaps tube residing in the middle of the boat. The boat is wrapped with 3-layers of Ta heatshields. Chamber is currently being pumped down. Good vac at 3.0e-5, bad vac at 4.0e-5 Torr. OMEGA slope = 0.98  Monday, February 06, 2017, 09:29 Power outage this weekend and evap2 tripped off. Re-pumping down now...  Tuesday, February 07, 2017, 08:54 HS water valves opened, no leaks detected. IGP1 = 1.9e-7 Torr Tapped up manually to 35A Vacuum stable. IGP1 = 2.0e-7 Torr Initiating auto-ramp at 0.2A/min with a final setpoint of 450A. Final desired temperature = 1800C  Wednesday, February 08, 2017, 09:52 IGP1 = 2.98e-7 Torr TGHT = 325A, 3.5V Vacuum stable. Increasing ramping rate to 1.0A/min  Wednesday, February 08, 2017, 11:46 IGP1 = 6.3e-7 Torr TGHT = 433A, 4.89V Increasing max setpoint to TGHT = 500A OMEGA has still yet to show a temperature...should be reading points at this high in current Will go down to the lab and follow up on OMEGA settings to confirm everything is set up ok before proceeding to a higher current...  Wednesday, February 08, 2017, 16:03 IGP1 = 4e-7 Torr TGHT = 500A, 5.75V OMEGA still not reading Initiating auto-cool at -2A/min Will update elog with more details tomorrow  Thursday, February 09, 2017, 10:52 Evap2 was cooled down and opened up this morning. Turns out both legs on the target boat were touching the new heatshield and therefore had been loosing power. Normally a boat at 500A would read ~1800C, in this scenario at 500A the boat read ~1000C. A lot of power was being lost into the heatshield. See photos attached of target boat sitting at 500A. The heatshield is currently being ground down in those two spots to accommodate the target boat.    Tuesday, February 14, 2017, 15:43 Heatshield was ground back and target boat now fits nicely into heatshield without contact.

 Tuesday, February 14, 2017, 15:44

Boat with endcaps and springs reloaded today and pumped back down this afternoon.

HS water valves opened, no leaks detected.

Tapped up manually to 35A

Vacuum stable.

IGP1 = 3.5e-6 Torr

Initiating auto-ramp at 0.2A/min with a final setpoint of 400A.

Final desired temperature = 1800C

 Wednesday, February 15, 2017, 10:24

IGP1 = 7.2e-7 Torr

TGHT = 260A, 3.95V

OMEGA = 1158C

Vacuum stable.

Increasing ramping rate to 1.0A/min.

 Wednesday, February 15, 2017, 13:02

IGP1 = 2.0e-6 Torr

TGHT = 400A, 6.67V

OMEGA = 1530C

Increasing final setpoint to 450A

 Wednesday, February 15, 2017, 13:55

IGP1 = 2.5e-6 Torr

TGHT =450A, 7.7V

OMEGA = 1640C

Increasing final setpoint to 500A

 Wednesday, February 15, 2017, 15:13

IGP1 = 1.8e-6 Torr

TGHT = 500A, 8.59V

OMEGA = 1770C

MIKRON = 1740C

Tapping up manually to ~1800C...

 Thursday, February 16, 2017, 09:09

IGP1 = 5.28e-7 Torr

TGHT = 520A, 9.1V

OMEGA = 1821C

Target boat has remained at max setpoints for 17.5hrs.

Initiating auto-cool at 1A/min

 Thursday, February 16, 2017, 13:49

Increasing auto-cool to 2.0A/min

 Friday, February 17, 2017, 16:00

Vented in air and opened up today.

Endcaps looks good  see photos attached

 Thursday, December 07, 2017, 09:57

Each endcap is wrapped in a separate piece of graphite foil and placed in a target boat.

There are also 4 coated springs, 2 on each side of the stack of endcaps.

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

Chamber pumped down overnight.

OMEGA slope = 0.98

HS water valves opened, no leaks detected.

IGP1 = 5.9e-7 Torr

IGP2 = 4.0e-7 Torr

Tapping up manually.

Final desired temperature = 1800C

Laura Lambert wrote:

Thursday, December 07, 2017, 09:57 Each endcap is wrapped in a separate piece of graphite foil and placed in a target boat. There are also 4 coated springs, 2 on each side of the stack of endcaps. The boat is wrapped with 3-layers of Ta heatshields. Chamber pumped down overnight. OMEGA slope = 0.98 HS water valves opened, no leaks detected. IGP1 = 5.9e-7 Torr IGP2 = 4.0e-7 Torr Tapping up manually. Final desired temperature = 1800C

 Thursday, December 07, 2017, 11:51

TGHT tripped off.

Turns out the vacuum limits have not been fully updated when they should have been and the old ones still apply.

IGP1 reached 8e-5 Torr which tripped off the system.

TGHT = 80A, 1.05V when the system tripped.

Laura Lambert wrote:

Laura Lambert wrote:  Thursday, December 07, 2017, 09:57 Each endcap is wrapped in a separate piece of graphite foil and placed in a target boat. There are also 4 coated springs, 2 on each side of the stack of endcaps. The boat is wrapped with 3-layers of Ta heatshields. Chamber pumped down overnight. OMEGA slope = 0.98 HS water valves opened, no leaks detected. IGP1 = 5.9e-7 Torr IGP2 = 4.0e-7 Torr Tapping up manually. Final desired temperature = 1800C    Thursday, December 07, 2017, 11:51 TGHT tripped off. Turns out the vacuum limits have not been fully updated when they should have been and the old ones still apply. IGP1 reached 8e-5 Torr which tripped off the system. TGHT = 80A, 1.05V when the system tripped.

 Friday, December 08, 2017, 15:29

Interlocks have been updated.

TGHT should now run up to 500mTorr before tripping off.

Laura Lambert wrote:

Laura Lambert wrote: Laura Lambert wrote:  Thursday, December 07, 2017, 09:57 Each endcap is wrapped in a separate piece of graphite foil and placed in a target boat. There are also 4 coated springs, 2 on each side of the stack of endcaps. The boat is wrapped with 3-layers of Ta heatshields. Chamber pumped down overnight. OMEGA slope = 0.98 HS water valves opened, no leaks detected. IGP1 = 5.9e-7 Torr IGP2 = 4.0e-7 Torr Tapping up manually. Final desired temperature = 1800C    Thursday, December 07, 2017, 11:51 TGHT tripped off. Turns out the vacuum limits have not been fully updated when they should have been and the old ones still apply. IGP1 reached 8e-5 Torr which tripped off the system. TGHT = 80A, 1.05V when the system tripped.    Friday, December 08, 2017, 15:29 Interlocks have been updated. TGHT should now run up to 500mTorr before tripping off.

Friday, December 08, 2017, 15:41

IGP1 = 2.8e-7 Torr

IGP2 = 1.9e-7 Torr

Tapped up manually to 50A

Initiated auto-ramp at a rate of 0.2A/min up to 300A.

Vacuum limit stop at 3.0e-5 Torr, backing off at 4.0e-5 Torr.

 Monday, December 11, 2017, 09:37

IGP1 = 2.4e-7

TGHT = 300A, 4.80V

OMEGA = 1175C

Tapping up manually...

 Monday, December 11, 2017, 14:19

Tapped up manually to 1800C

IGP1 = 2.1e-6 Torr

IGP2 = 2.1e-6 Torr

TGHT = 545A, 9.90V

OMEGA = 1810C

Will remain at max setpoints overnight and cool down in the a.m.

 Tuesday, December 12, 2017, 09:01

TGHT = 545A, 9.96V

OMEGA = 1833C

Remained at max setpoints for ~18hrs

IGP1 = 4.2e-7 Torr

IGP2 = 3.9e-7 Torr

Initiating auto-cool at 2.0A/min

 Wednesday, December 13, 2017, 11:05

Vented in air and removed from evap2 this morning.

Tuesday, June 04, 2019, 08:36

Each endcap is separated with a disc of graphite foil and rolled into packs of 5 within a foil envelope in a target boat.

There are also 4 coated springs, 2 on each side of the stack of endcaps.

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

Chamber pumped down overnight.

OMEGA slope = 0.99

IGP1 = 3.5e-7 Torr

Will Tap TGHT up manually to 40 A then autoramp to 400A at 1A/min.

Final desired temperature on OMEGA (tap)= 1800C

Tuesday, June 04, 2019, 11:54

IGP1= 6.1e-06 Torr

TGHT= 40 A

Begin autoramp to 400A at 1A/min

Out-gassing cycles observed.  Reduced autoramp to 0.5A/min

Currently TGHT=65A, 0.60 V

Wednesday, June 05, 2019, 08:27

TGHT = 321A, 4.9V @1149C

IGP1= 8.49 e-6 Torr

Set autoramp to 1A/min to530 A

Wednesday, June 05, 2019, 13:26

TGHT 530A, 9.2V

IGP1= 3.01e-05 Torr

OMEGA Temperature = 1689 Celsius

Set autoramp to 570A at 1A/min

 Wednesday, June 05, 2019, 15:51

Tapped manually to 1800 Celsius

TGHT 579A, 10.1V

IGP1= 2.06e-05 Torr

TGHT tapped down to 575A when OMEGA T ~1810 C

Thursday, June 06, 2019, 08:13

TGHT = 575A, 9.95V

OMEGA = 1809 C

IGP1 = 4.1e-7 Torr

Initiating auto-cool at -2.0A/min

Thursday, June 06, 2019, 16:00

After 1 hour  of TGHT at 0A and 0V, unloaded the Target boat.

Monday, November 04, 2019, 14:19 

Each endcap is separated with a disc of graphite foil and rolled into packs one pack of 4 and one pack of 8 within a foil envelope in a target boat.

There are also 3 coated springs interspersed.

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

Chamber pumped down overnight.

OMEGA slope = 0.99

Will Tap TGHT up to 40 A then autoramp to 400A at 1A/min.

Final desired temperature on OMEGA (tap)= 1800C

 Tuesday, November 05, 2019, 11:30

IGP1 = 9.6e-7 Torr

Autoramp TGHT to 40A at 1A/min

Tuesday, November 05, 2019, 11:44

IGP1= 2.6e-06 Torr

TGHT = 40.8 A, 0.37V

Will leave at 40 A for 1 hour

 Tuesday, November 05, 2019, 12:39

 IGP1=2.5e-6 Torr

TGHT =40.0A, .33V

Start ramping TGHT to 400A at 0.1A/min

Wednesday, November 06, 2019, 09:32

IGP1=7.8e-7 Torr

TGHT = 168.4A, 2.38V

increase ramp speed to 1A/min

 Wednesday, November 06, 2019, 14:07

IGP1= 2.34e-6 Torr

TGHT=400.0 A, 6.98V

set TGHT autoramp to 460A @ 1A/min aiming for 1850C (see attached plot)

Wednesday, November 06, 2019, 15:18

OMEGA = 1776 C

TGHT = 460.0A, 8.52V

IGP1= 4.7e-6 Torr

Starting manual tap up to 1810C

Wednesday, November 06, 2019, 15:36

OMEGA=1810 C

TGHT = 468.8A, 8.74V

IGP1=4.14e-6

Wednesday, November 06, 2019, 19:04

OMEGA=1822 C (has been between 1817-1824 C over 3.5 hours )

TGHT=468.8A, 8.67V

IGP1=1.9498e-06 Torr

Start TGHT ramp down at -2A/min

Thursday, November 07, 2019, 09:55

THGT = 0A, 0V overnight

IGP1= 3.2 e-07 Torr

Proceeding with unloading.

End caps looked good for online use.

Monday, November 08, 2021, 09:35

Two groups of 4 caps wrapped in graphite with graphite discs in between. 

Two TaC coated springs at either end of the boat.

Target temperature = 1800 C

Expected around 430 TGHT

Good Vacuum 3e-03 Torr

Bad Vacuum 5e-02 Torr

Evap two was left pressuring down over weekend.

Monday, November 08, 2021, 09:35

Starting autoramp to 40 A at 1A/min

TGHT = 2.5e-07 Torr

Monday, November 08, 2021, 10:57

IGP1 = 8.5e -06 Torr and dropping

set autoramp to 50A at 1A/min

IGP1 1.0e-05 Torr and dropping

Set TGHT to autoramp to 90 A @ 1A/min and leave until pressure below 9e-06 Torr

Monday, November 08, 2021, 15:09

IGP1= 9.6e-06 Torr

Start autoramp to 400A at 2A/min 

Monday, November 08, 2021, 17:37

TGHT = 377 A, 6.1V

OMEGA= 1234 C

Monday, November 08, 2021, 17:58

OMEGA = 1292 (cannot trust )

400A, 6.3 V

1.4 e-05 Torr

 Autoramp @ 1A/min to 425A

Will heat to 425A and keep there for four hours

Monday, November 08, 2021, 22:02

TGHT=420A, 6.7V

IGP1= 7.0e-06 Torr

Start ramp down at -2A/min 

Thursday, March 09, 2023, 06:53

2 TaC coated springs and  12 Tac coated caps loaded into a target boat (in packs of 4 wrapped in graphite foil).

Target boat wrapped in 4 Ta heatshields

Target boat type was with endcaps at both ends.

Left in Evap2 over previous night to depressurize.

Target temperature= 1850-1900C for 4 hours

Good vacuum = 5e-04 Torr

Bad vacuum = 5e-02 Torr

Start autoramp at 2A/min to 50A on  TGHT

 Thursday, March 09, 2023, 07:22

at 44A switched ramping rate to 1A/min to 120 A

Thursday, March 09, 2023, 09:53

ramping at 4A/min (2A/30s) to 400A

IGP1= 9.9e-07 Torr

Thursday, March 09, 2023, 11:26

1130 am  reaching 425A on TGHT 

1850 C OMEGA

Thursday, March 09, 2023, 15:37

TGHT 425 A, 7.1V

OMEGA = 1850 C

Starting rampdown @ -2A/min

endcaps and spring looked really good.

A boat lined up with graphite and wrapped in 3 Ta heatshileds

Vacuum IGP1 initial =6.1 e-06 Torr

Target temperature on OMEGA= 1800-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final TGHT current= ~400A (adjustable)

Heating autoramp started semi-manually on  TGHT  to 65A and then at continue to 100A

After peak heat at 1A/min  to =400 A TGHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Tuesday, September 10, 2024, 22:22

1810C OMEGA at 439A TGHT readback

 Tuesday, February 28, 2012, 10:36

Two thermocouples were inserted through the left side of the copper heat shield, see attachment #1.  One thermocouple is attached to the target tube with a Ta-wire, and the other is attached to the back block.

Data gathering: 

1.  Target heater (IEVAP2:TGHT) setpoint current/voltage  

2.  Target heater (IEVAP2:TGHT) readback current/voltage

4.  Tube heater (IEVAP2:TBHT) setpoint current/voltage

3.  Thermocouples voltages & controls' readback (IEVAP2:TCM) 

Tuesday, April 03, 2012, 08:54

Yesterday, a new target boat was sprayed with TaC coating and let dried.

The boat was then installed in the Evap#2 chamber and pumped down to 10-6 Torr before the target heater was turned on.  NOTE: Target boat is not wrapped with Ta-heat shield. 

TGHT auto ramping was initiated at 2.0A/min and max setpoint to 700A.  The voltage was set at 3V; therefore, the current only ramped up to 250A over night.

--> Increased the TGHT voltage to 15A, and continue ramping the TGHT to 700A.  Currently vac at low 2.3e-7 Torr. 

 Tuesday, April 03, 2012, 09:12

The vac is at low 10e-7 as the TGHT is ramping up.  Changing ramping rate from 2A/min to 5A/min. 

Tuesday, April 03, 2012, 12:00  

TGHT reached to 700A. Measured temp @ 1280C. 

Tapped up TGHT to:

800A.  Measured temp @ 1400C. 

850A (local 843A/15.60V). Measured temp @ 1450C.  

900A (local 893A/16.88V).  Measured temp @ 1500C

 Tuesday, April 03, 2012, 14:35:

Try autoramping TGHT to 1000A but voltage has gone up close to the max limit (20V).  TGHT could only go up to ~970A (see attachment 1: TGHT_maxcurrent.jpg).  The heater remained at that current for ~1hr but auto cooling was initiated - at 10A/min.

Thursday, July 19, 2012, 16:58

The target container was coated with TaC. 

It's wrapped with 3 layers of Ta as the heat-shield, including the backblock.

TGHT will be ramped up to 580A at 0.2A/min.

TBHT will be ramped up to 230A at 0.2A/min.

Currently, IGP1 = 1.5e-6 Torr.  BP = 15mTorr

 Friday, July 20, 2012, 13:56

TGHT and TBHT reached to 580A & 230A, respectively, and stayed for ~ 2hrs. 

Measured temperature at the ionizer tube to be 1630C.

Cooling down in process at 2A/min...

 Sunday, July 22, 2012, 20:53

The chamber was vented earlier around 14:00hr.  

The target container looks good!