Tuesday, May 07, 2024, 06:16

TP was swapped on previous day (May 6th)

protective screen installed.

Loaded 9 TaC coated end caps (groups of 4 and 5) and 2 TaC coated springs.

OMEGA Slope 0.99

Will heat to 1850-1900 C and hold for 4 hours

Good Vac = 5.0e-4 Torr

Bad Vac= 5.0 e-02 Torr

 Initial IGP1=6.7E-07 Torr

Friday, October 04, 2013, 15:37

A LP target container is coated with TaC.  The container is wrapped with 3 layers to heat shield.  

This container will be used for the graphite tube test.  

Chamber is being pumped down.

 The HS cooling water valves are open and no leaks are detected. 

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

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

The temperature will be monitored and measured. 

 Sunday, October 06, 2013, 19:55

Tuesday, October 22, 2013, 16:49

The target was heated up to 580A and the temperature inside the tube was measured to be ~1800C and the outside surface was ~1400C.

The target was cooled down.  Then the graphite tube was inserted.

There are two thermcouples inserted inside the tube on both ends.

Chamber has been pumped down to 4.33 e-7 Torr.  No leaks were detected.

Target will be heated up again to TGHT @ 580A / TBHT @ 230A at 0.2A/min.

The temperatures will be monitored.

T1 = left (floating)

T2 = right (toughing C-grv tube)

(wtf ionizer pointing into the page).

 Thursday, October 24, 2013, 16:35

TGHT/TBHT reached to 580A/230A. 

T1 = 1642C

T2 = Error?? Reading goes on/off intermittently, showing 900 - 1900C

Thursday, October 24, 2013, 16:45 

Ramping up TGHT to 680A to see if T1 can reach 1700C.

IG1 currently at 5.2e-7 Torr.

 Friday, October 25, 2013, 12:30

TGHT was ramped up to 632A (stopped due to voltage limiting). 

T1 was measured at 1960C.  Vac went up as it was heated up.  (see attachment #2)

Target was cooled down at 5A/min, now at 0A.

The chamber will be vented and the target will be inspected.

This run is complete.

 Wednesday, February 28, 2018, 15:16

Container coated with TaC using 'flushing technique' and let dry.

Q-tip to plug ionizer became stuck in ionizer, removed manually with small drill bit.

Inspected ionizer with microscope, ionizer still good.

Cleaned ionizer tube with acetone.

Wrapped with 3 x Ta heat shields, incl center block

Currently pumping down in evap2

OMEGA slope = 0.98

Good vac at 3.0e-5, bad vac at 8.0e-5 Torr.

 Thursday, March 01, 2018, 10:06

HW water valves opened yesterday, no leaks detected.

IGP1 = 2.8e-7 Torr

Tapped up manually to 40A.

Waited ~3hrs

Vacuum stable.

IGP1 = 5.3e-7 Torr

IGP2 = 5.4e-7 Torr

Initiating auto ramp for TGHT @ 1.0A/min to a max setpoint of 350A

Initiating auto ramp for TBHT @ 0.5A/min to a max setpoint of 230A

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

 Thursday, March 01, 2018, 14:39

Vacuum started to climb very fast - auto-ramp was stopped.

Vacuum climbed up to IGP1 = 1.3e-4 Torr

Tapped TGHT back down to 80A from 90A, TBHT down to 50A from 60A.

Waited ~40min.

Vacuum stable, IGP1 = 2.6e-6 Torr

Restarting auto-ramp.

 Thursday, March 01, 2018, 14:54

IGP1 = 2.1e-5 Torr

Vacuum climbing quite rapidly again, stopped auto-ramp and vacuum started to drop right away.

TGHT = 100A

TBHT = 56A

Waited ~10min

IGP1 = 6.0e-6 Torr

IGP2 = 5.2e-6 Torr

Decreasing ramping rate to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively, and re-initiating auto-ramp.

 Friday, March 02, 2018, 10:18

TGHT = 350A, 5.61V

TBHT = 230A, 4.04V

IGP1 = 4.3e-7 Torr

IGP2 = 3.8e-7 Torr

OMEGA = 1624C

Vacuum stable.

Increasing max setpoint of TGHT to 400A

Re-initiating auto-ramp of TGHT.

 Friday, March 02, 2018, 11:04

TGHT = 372A, 6.05V

IGP1 = 5.0e-7 Torr

Increasing ramping rate for TGHT to 1.0A/min

 Friday, March 02, 2018, 11:44

TGHT = 400A, 6.60V

IGP1 = 6.9e-7 Torr

OMEGA = 1780C

Vacuum stable.

Increasing max setpoint of TGHT to 430A

Re-initiating auto-ramp of TGHT.

 Friday, March 02, 2018, 12:17

TGHT = 430A, 7.22V

OMEGA = 1866C

IGP1 = 9.5e-7 Torr

Tapped up manually to OMEGA = 1910C

TGHT = 445A, 7.57V

TBHT = 230A, 4.07V

IGP1 = 1.1e-6 Torr

IGP2 = 9.9e-7 Torr

 Monday, March 05, 2018, 08:41

Remained at max setpoints over the weekend.

TGHT = 445A, 7.47V

TBHT = 230A, 4.06V

IGP1 = 1.87e-7 Torr

IGP2 = 1.47e-7 Torr

OMEGA = 1894C

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

 Tuesday, March 20, 2018, 14:53

Vented in air.

Container was transferred to glove box for loading ~1 week ago

Container looks good.

 Monday, June 05, 2017, 15:20

Container coated with TaC using 'flushing technique' and let dry over weekend.

Cleaned ionizer tube with acetone, no coating inside ionizer tube.

Wrapped with 3 x Ta heat shields, incl center block

Currently pumping down in evap2

OMEGA slope = 0.98

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

 Tuesday, June 06, 2017, 10:00

First time not turning water off and flushing lines after last use.

HS water valves have remained open since the last time evap2 was used [conditioning Ta#52]

No leak check done.

Tapped up manually to 35A.

Waited ~25min

Vacuum stable.

IGP1 = 2.9e-6 Torr

IGP2 = 4.8e-6 Torr

Initiating auto ramp for TGHT @ 0.2A/min to a max setpoint of 350A

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

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

 Wednesday, June 07, 2017, 09:26

TGHT = 304A, 4.46V

TBHT = 169A, 2.769V

IGP1 = 6.1e-7 Torr

IGP2 = 7.3e-7 Torr

Vacuum stable.

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

 Wednesday, June 07, 2017, 10:40

TGHT = 350A, 5.28V

TBHT = 203A, 3.39V

IGP1 = 1e-6 Torr

Increasing ramping rate for TBHT to 1.0A/min

Wednesday, June 07, 2017, 12:10 

TGHT = 350A, 5.26V

TBHT = 230A, 3.99V

IGP1 = 7.0e-7 Torr

IGP2 = 8.3e-7 Torr

OMEGA = 1600C

Vacuum stable.

Increasing max setpoint of TGHT to 400A

Re-initiating ramping rate of TGHT at 1.0A/min

 Wednesday, June 07, 2017, 15:42

Tapped up to reach final desired temperature.

TGHT = 450A, 7.28V

TBHT = 230A, 4.02V

IGP1 = 9.0e-7 Torr

IGP2 = 1.07e-6 Torr

OMEGA = 1910C

Will remain at max setpoints overnight.

 Thursday, June 08, 2017, 08:51

Remained at max setpoints for 17hrs.

TGHT = 450A, 7.28V

TBHT = 230A, 4.02V

IGP1 = 2.6e-7 Torr

IGP2 = 2.9e-7 Torr

OMEGA = 1899C

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

 Thursday, June 08, 2017, 16:28

 Vented in air and taken out this afternoon.

Container looks good!

Transferred into glove box.

 Friday, May 22, 2015, 11:43

A target boat was sprayed with TaC coating and let dry yesterday.

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

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

 Friday, May 22, 2015, 14:22

HS water valves opened, no leaks detected.

IGP1 = 2.4e-6 Torr.

Tapping up manually...

 Friday, May 22, 2015, 14:33

Tapped up to 20A.

Vacuum jumped up to 7e-6 Torr.

Backed off to 5A before vacuum started to drop again.

IGP1 = 5e-6 Torr.

Tapping up manually again...just more slowly...

 Friday, May 22, 2015, 15:31

Tapped up to 12A, unable to tap up very fast due to volatile content in coating.

IGP1 = 3.6e-6 Torr.

Initiating auto-ramp at 0.1A/min with a max current of 580A.

 Monday, May 25, 2015, 09:03

IGP1 = 3e-7 Torr.

TGHT = 397.5A, 6.43V

Increasing ramping rate to 1.0A/min.

Laura Lambert wrote:

Friday, May 22, 2015, 11:43 A target boat was sprayed with TaC coating and let dry yesterday. The target boat is wrapped with 3-layers of Ta-heat shield. The boat was installed in EVAP2, chamber is currently being pumped down.  Friday, May 22, 2015, 14:22 HS water valves opened, no leaks detected. IGP1 = 2.4e-6 Torr. Tapping up manually...  Friday, May 22, 2015, 14:33 Tapped up to 20A. Vacuum jumped up to 7e-6 Torr. Backed off to 5A before vacuum started to drop again. IGP1 = 5e-6 Torr. Tapping up manually again...just more slowly...  Friday, May 22, 2015, 15:31 Tapped up to 12A, unable to tap up very fast due to volatile content in coating. IGP1 = 3.6e-6 Torr. Initiating auto-ramp at 0.1A/min with a max current of 580A.  Monday, May 25, 2015, 09:03 IGP1 = 3e-7 Torr. TGHT = 397.5A, 6.43V Increasing ramping rate to 1.0A/min.

 Monday, May 25, 2015, 17:06

TGHT at been at 580A for over 4 hours.  Cooling down in process at 1A/min. 

John Wong wrote:

Laura Lambert wrote:  Friday, May 22, 2015, 11:43 A target boat was sprayed with TaC coating and let dry yesterday. The target boat is wrapped with 3-layers of Ta-heat shield. The boat was installed in EVAP2, chamber is currently being pumped down.  Friday, May 22, 2015, 14:22 HS water valves opened, no leaks detected. IGP1 = 2.4e-6 Torr. Tapping up manually...  Friday, May 22, 2015, 14:33 Tapped up to 20A. Vacuum jumped up to 7e-6 Torr. Backed off to 5A before vacuum started to drop again. IGP1 = 5e-6 Torr. Tapping up manually again...just more slowly...  Friday, May 22, 2015, 15:31 Tapped up to 12A, unable to tap up very fast due to volatile content in coating. IGP1 = 3.6e-6 Torr. Initiating auto-ramp at 0.1A/min with a max current of 580A.  Monday, May 25, 2015, 09:03 IGP1 = 3e-7 Torr. TGHT = 397.5A, 6.43V Increasing ramping rate to 1.0A/min.    Monday, May 25, 2015, 17:06 TGHT at been at 580A for over 4 hours.  Cooling down in process at 1A/min.

 Vented in air and opened up this morning.

Target boat looks good! fully sintered! 

 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, 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]

John Wong wrote:

Laura Lambert wrote:  Tuesday, May 26, 2015, 13:06 Endcaps were sprayed with TaC coating and let dry. Each endcap is wrapped separately with a sheet of graphite foil and stacked in the target boat [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.  Wednesday, May 27, 2015, 08:50 HS water valves opened, no leaks detected. Stepped up manually to 35A. Initiated auto-ramp at 0.2A/min yesterday afternoon. TGHT = 254A, 3.56V. IGP1 = 5.9e-7 Torr. Increasing ramping rate to 1.0A/min with a max setpoint of 400A.    Wednesday, May 27, 2015, 17:51 TGHT has been at 400A for almost 6 hours.  Temp at 1500C. Cooling down to 0A at 1A/min. Chamber will be vented to inspect the caps.  May have to remove the graphite foil wrapped on the caps and re-sintered the caps to 1800C.

 Thursday, May 28, 2015, 08:13

Vented in air and opened up this morning.

Not fully sintered [see pictures]

 Tuesday, May 26, 2015, 13:06

Endcaps were sprayed with TaC coating and let dry.

Each endcap is wrapped separately with a sheet of graphite foil and stacked in the target boat [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.

 Wednesday, May 27, 2015, 08:50

HS water valves opened, no leaks detected.

Stepped up manually to 35A.

Initiated auto-ramp at 0.2A/min yesterday afternoon.

TGHT = 254A, 3.56V.

IGP1 = 5.9e-7 Torr.

Increasing ramping rate to 1.0A/min with a max setpoint of 400A.

Laura Lambert wrote:

Tuesday, May 26, 2015, 13:06 Endcaps were sprayed with TaC coating and let dry. Each endcap is wrapped separately with a sheet of graphite foil and stacked in the target boat [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.  Wednesday, May 27, 2015, 08:50 HS water valves opened, no leaks detected. Stepped up manually to 35A. Initiated auto-ramp at 0.2A/min yesterday afternoon. TGHT = 254A, 3.56V. IGP1 = 5.9e-7 Torr. Increasing ramping rate to 1.0A/min with a max setpoint of 400A.

 Wednesday, May 27, 2015, 17:51

TGHT has been at 400A for almost 6 hours.  Temp at 1500C.

Cooling down to 0A at 1A/min.

Chamber will be vented to inspect the caps. 

May have to remove the graphite foil wrapped on the caps and re-sintered the caps to 1800C.

 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]

Laura Lambert wrote:

Thursday, November 05, 2015, 16:19 Springs coated with TaC and loaded into container for sintering. 3x Ta heat shield. EVAP2 currently pumping down.  Friday, November 06, 2015, 08:39 Opened HS water valves, no leaks detected. Tapped up manually to 35A. IGP1 = 5.5e-7 Torr.  Friday, November 06, 2015, 10:08 IGP1 = 5.8e-7 Torr. Vacuum stable. Initiating auto-ramp at 0.2A/min and 0.1A/min with final setpoints of 450A and 230A for the TGHT and TBHT respectively. See photos attached to view how springs were coated and loaded into container.  Monday, November 09, 2015, 09:07 TGHT reached 450A, 7.2V ~8pm sat, nov 7th. OMEGA = 1775C IGP1 = 3.2e-7 Torr. Tapping up manually to 1900C.

 Monday, November 09, 2015, 12:30

Checked the temp on the inner surface (not at the spring) of the container was around 2050C at 500A. 

The TaC coated spring is reading at 1900C; that's what the OMEGA is reading with the setting for 2-colors and slope at 0.98.

Lower TGHT to 450A/ 7.12V.

By comparing the data from the previous temp curve (OMEGA slope at 0.98) with no material inside the container,  the voltage and current plot is aligned with the curve.

Changed OMEGA setting slope to 1.04.  Current temp is reading at 1917C at 450A.

For 2-Color setting, the emissivity should be negligible.  That makes me believe that different materials has different slope setting for the temp reading.  

One thing to note is that, the sintering temp of TaC is around 1900-2000C.  It was clear that the container was fully sintered with TGHT at 450A.

Will need to gather more data with different material to understand the slope setting better. 

Try: 

SiC at 1700C, slope at 1.04

ZrC at 1900C, slope at 104

Ta at 1900C, slope at 0.98.

Compare the data...

John Wong wrote:

Laura Lambert wrote:  Thursday, November 05, 2015, 16:19 Springs coated with TaC and loaded into container for sintering. 3x Ta heat shield. EVAP2 currently pumping down.  Friday, November 06, 2015, 08:39 Opened HS water valves, no leaks detected. Tapped up manually to 35A. IGP1 = 5.5e-7 Torr.  Friday, November 06, 2015, 10:08 IGP1 = 5.8e-7 Torr. Vacuum stable. Initiating auto-ramp at 0.2A/min and 0.1A/min with final setpoints of 450A and 230A for the TGHT and TBHT respectively. See photos attached to view how springs were coated and loaded into container.  Monday, November 09, 2015, 09:07 TGHT reached 450A, 7.2V ~8pm sat, nov 7th. OMEGA = 1775C IGP1 = 3.2e-7 Torr. Tapping up manually to 1900C.    Monday, November 09, 2015, 12:30 Checked the temp on the inner surface (not at the spring) of the container was around 2050C at 500A.  The TaC coated spring is reading at 1900C; that's what the OMEGA is reading with the setting for 2-colors and slope at 0.98. Lower TGHT to 450A/ 7.12V. By comparing the data from the previous temp curve (OMEGA slope at 0.98) with no material inside the container,  the voltage and current plot is aligned with the curve. Changed OMEGA setting slope to 1.04.  Current temp is reading at 1917C at 450A. For 2-Color setting, the emissivity should be negligible.  That makes me believe that different materials has different slope setting for the temp reading.   One thing to note is that, the sintering temp of TaC is around 1900-2000C.  It was clear that the container was fully sintered with TGHT at 450A. Will need to gather more data with different material to understand the slope setting better.  Try:  SiC at 1700C, slope at 1.04 ZrC at 1900C, slope at 104 Ta at 1900C, slope at 0.98. Compare the data...

 Monday, November 09, 2015, 14:20

IGP1 = 3.3e-7 Torr.

TGHT = 450A, 7.12V

OMEGA = 1915C

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

 Tuesday, November 10, 2015, 13:23

Vented and opened this morning.

springs look [mostly] sintered.

see photo attached.