John Wong wrote:

Laura Lambert wrote:  Thursday, June 04, 2015, 9:07 Container was sprayed with TaC and let dry. Container has 3x Ta heat shields including center block. Container was loaded into EVAP2 yesterday and pumped down overnight. HS water valves were opened up this morning, no leaks detected. IGP1 = 4.6e-7 Torr. Tapped up manually to 40A. Waited ~25min, Vacuum stable. IGP1 = 5.0e-7 Torr. Initiating auto-ramp. TGHT will be ramped to reach 2000C  Friday, June 05, 2015, 10:01 IGP1 = 4.5e-7 Torr. TGHT = 313A, 4.47V OMEGA = 1444C Increasing ramping rate to 1.0A/min  Friday, June 05, 2015, 11:31 IGP1 = 1.2e-6 Torr. Increasing ramping rate to 2.0A/min    Friday, June 05, 2015, 12:01 TGHT reached to 465A/7.56V, temp is stable at 2000C. Current vac at 1.2e-6 Torr and coming down Cooling down process can be initiated after 4 hours.

 Friday, June 05, 2015, 13:21

OMEGA = 1995C

Increasing TGHT to 470A to achieve desired max temperature of 2000C

Friday, June 05, 2015, 15:59

TGHT sat at max desired temperature of 2000C for ~4hrs.

TGHT = 470A, 7.7V

Initiating auto-cool at 1.0A/min.

 Monday, June 08, 2015, 11:31

Vented in air and opened up this morning.

Target container mostly sintered, two tiny patches near both ends not fully sintered.

Will re-install and re-sinter next week as another container with priority needs to be sintered first.

 Tuesday, June 09, 2015, 10:45

See attachements for 'not-fully-sintered' photos

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote:  Thursday, June 04, 2015, 9:07 Container was sprayed with TaC and let dry. Container has 3x Ta heat shields including center block. Container was loaded into EVAP2 yesterday and pumped down overnight. HS water valves were opened up this morning, no leaks detected. IGP1 = 4.6e-7 Torr. Tapped up manually to 40A. Waited ~25min, Vacuum stable. IGP1 = 5.0e-7 Torr. Initiating auto-ramp. TGHT will be ramped to reach 2000C  Friday, June 05, 2015, 10:01 IGP1 = 4.5e-7 Torr. TGHT = 313A, 4.47V OMEGA = 1444C Increasing ramping rate to 1.0A/min  Friday, June 05, 2015, 11:31 IGP1 = 1.2e-6 Torr. Increasing ramping rate to 2.0A/min    Friday, June 05, 2015, 12:01 TGHT reached to 465A/7.56V, temp is stable at 2000C. Current vac at 1.2e-6 Torr and coming down Cooling down process can be initiated after 4 hours.     Friday, June 05, 2015, 13:21 OMEGA = 1995C Increasing TGHT to 470A to achieve desired max temperature of 2000C Friday, June 05, 2015, 15:59 TGHT sat at max desired temperature of 2000C for ~4hrs. TGHT = 470A, 7.7V Initiating auto-cool at 1.0A/min.  Monday, June 08, 2015, 11:31 Vented in air and opened up this morning. Target container mostly sintered, two tiny patches near both ends not fully sintered. Will re-install and re-sinter next week as another container with priority needs to be sintered first.  Tuesday, June 09, 2015, 10:45 See attachements for 'not-fully-sintered' photos

 Wednesday, June 10, 2015, 12:06

After inspecting the target container,  the inner tube surface has "dark" patches, which may not be evenly coated or the coating layer was too think.  

See link for photos:  https://www.dropbox.com/sh/m94mjuuodwhz5jb/AADEBv_Kha_p_1An40eftWNHa?dl=0 

Attempt to re-spray the container and re-sinter.  

John Wong wrote:

Laura Lambert wrote: John Wong wrote: Laura Lambert wrote:  Thursday, June 04, 2015, 9:07 Container was sprayed with TaC and let dry. Container has 3x Ta heat shields including center block. Container was loaded into EVAP2 yesterday and pumped down overnight. HS water valves were opened up this morning, no leaks detected. IGP1 = 4.6e-7 Torr. Tapped up manually to 40A. Waited ~25min, Vacuum stable. IGP1 = 5.0e-7 Torr. Initiating auto-ramp. TGHT will be ramped to reach 2000C  Friday, June 05, 2015, 10:01 IGP1 = 4.5e-7 Torr. TGHT = 313A, 4.47V OMEGA = 1444C Increasing ramping rate to 1.0A/min  Friday, June 05, 2015, 11:31 IGP1 = 1.2e-6 Torr. Increasing ramping rate to 2.0A/min    Friday, June 05, 2015, 12:01 TGHT reached to 465A/7.56V, temp is stable at 2000C. Current vac at 1.2e-6 Torr and coming down Cooling down process can be initiated after 4 hours.     Friday, June 05, 2015, 13:21 OMEGA = 1995C Increasing TGHT to 470A to achieve desired max temperature of 2000C Friday, June 05, 2015, 15:59 TGHT sat at max desired temperature of 2000C for ~4hrs. TGHT = 470A, 7.7V Initiating auto-cool at 1.0A/min.  Monday, June 08, 2015, 11:31 Vented in air and opened up this morning. Target container mostly sintered, two tiny patches near both ends not fully sintered. Will re-install and re-sinter next week as another container with priority needs to be sintered first.  Tuesday, June 09, 2015, 10:45 See attachements for 'not-fully-sintered' photos    Wednesday, June 10, 2015, 12:06 After inspecting the target container,  the inner tube surface has "dark" patches, which may not be evenly coated or the coating layer was too think.   See link for photos:  https://www.dropbox.com/sh/m94mjuuodwhz5jb/AADEBv_Kha_p_1An40eftWNHa?dl=0  Attempt to re-spray the container and re-sinter.

 Friday, June 12, 2015, 14:58

re-sprayed with second layer of TaC spray this morning.

re-loaded into evap2.

HS water valves opened, no leaks detected.

will ramp-up over weekend.

 Tuesday, February 11, 2014, 13:43

Target container is coated with TaC and wrapped with 3-Ta heat shields.

TGHT and TBHT will be ramped up to 820A and 300A, respectively.

Ramping rate set to 0.2A/min.

Good vac = 3e-5 Torr, Bad vac = 4e-5 Torr.

Chamber currently being pumped down...

 Tuesday, February 11, 2014, 16:33

Chamber pumped down to 2e-6 Torr.

HS cooling water valves opened; no leaks detected.

Will step up in the a.m.

 Wednesday, February 12, 2014, 11:41

IGP1 = 1.5e-7 Torr

TGHT max voltage = 17.05V, TBHT max voltage = 5V

Stepped TGHT and TBHT up to 35A

Waited 1hr15 before vacuum stabilized/ started to drop.

Initiating auto-ramping.

 Thursday, February 13, 2014, 10:19

TBHT and TGHT have both reached 300A

IGP1 = 2.4e-7 Torr.

Increasing TGHT auto-ramp to 2.0A/min

 Friday, February 14, 2014, 08:58

TGHT reached 820A yesterday afternoon. Measured internal temp this morning at 1300C.

Initiated TGHT auto-cooling at 2.0A/min and TBHT at 1.0A/min.

IGP1 = 3.2e-7 Torr.

 Monday, February 17, 2014, 12:02

Cooled down friday. Vented this morning.

Container fully sintered, smooth run!

 Friday, January 31, 2014, 11:28

Target container is coated with TaC.

The container is wrapped with 3 x Ta heat-shield.

Chamber was pumped down to 1.9e-7 Torr.

HS water valves were opened, no leak detected.

TGHT and TBHT were stepped up to 35A. Waited ~20min, current stabilized and vacuum starting to drop.

TGHT will be ramped up to 580A at 0.2A/min, max voltage = 11.05V.

TBHT will be ramped up to 230A at 0.2A/min, max volatge = 5V.

Initiating auto-ramping: Good Vac = 3.0e-5 Torr, Bad Vac = 4.0e-5 Torr.

 Monday, February 03, 2014, 10:21

TGHT reached 580A pver the weekend.

TBHT sitting at 1.4A, checked archive: never went over 1.6A. Aborted auto-ramp, re-starting auto ramp process for TBHT.

IGP1 = 1.6e-7 Torr.

 Monday, February 03, 2014, 15:23

TBHT running smoothly, must have been and electrical problem.

TBHT currently at 85A, vacuum has not changed, increasing TBHT auto-ramp to 2.0A/min

 Tuesday, February 04, 2014, 10:10

TBHT reached 230A yesterday pm. Measured temp this morning at 1800C.

Initiated TGHT/TBHT auto-cooling at 2.0A/min.

 Wednesday, February 05, 2014, 11:33

Chamber cooled down overnight, vented and opened up this morning.

Smooth run! Container fully sintered.

 Thursday, April 09, 2015, 09:33

Target container is coated with TaC and wrapped with 3-Ta heat shields, not incl center block.

TGHT and TBHT will be ramped up to 820A and 230A, respectively.

Chamber pumped down overnight.

IGP1 = 5.2e-7 Torr.

HS cooling water valves opened; no leaks detected.

TGHT max voltage = 18V, TBHT max voltage = 5V

Stepping TGHT and TBHT up to 35A...

 Thursday, April 09, 2015, 10:07

Waited ~20min, vacuum stable.

IGP1 = 5.3e-7 Torr.

Good vac = 3e-5 Torr. Bad vac = 4e-5 Torr.

Auto-ramp initiated at 0.2A/min.

 Monday, April 13, 2015, 09:06

Reached max setpoints sunday morning [see attached photo for striptool].

Internal temperature measured with OMEGA  = 1965C

IGP1 = 4.4e-7 Torr,

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

 Tuesday, April 14, 2015, 14:12

Vented in air and opened up this morning.

Fully sintered.

 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

 Wednesday, September 07, 2016, 14:45

Container was previously coated with TaC solution and wrapped with 1-full length layer of Ta- heat shield around the fins.  

Chamber is being pumped down.  Vac at 5.6e-7 Torr before HS water valves were open; no leaks were detected. 

Sintering Temperature 1900C (Omega slope @ 0.98); expected TGHT ~765A/11.90V, TGHT max at 230A.

 Thursday, September 08, 2016, 18:14

At about 1600C, it was observed that the coating inside the tube seems to chip off (see attachment 1).

TGHT was ramped up to 745A/11.85V and TBHT to 230A/3.25V.  Temperature measured on OMEGA/Mikron = 1914C/1881C; both instruments slopes set at 0.98.

Will remain at this TGHT current over night

Vac at 3.0e-6 Torr and coming down.

Friday, September 09, 2016, 11:01 

Target has been heated at the stable temperature at 1914C (for OMEGA) and 1881C (for Mikron) with current at 745A/11.94V (see attachment 2) for almost 19 hours. 

No fluctuation in p/s current or temperature was observed.  The ramping up process is captured and can be view from the link below:

https://www.dropbox.com/sh/9lgtin54o17ds6j/AABn1-XjvK44mm74TjqTAmvta?dl=0

Pressure at 1.07e-6 Torr. 

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

Continue to capture the cooling down process. 

 Friday, September 09, 2016, 15:17

 While the target container was cooling down, the chip-like particle began obvious (see attachment 3).  

Will inspect the container.. TGHT currently at 260A.

 Tuesday, August 25, 2015, 11:50

Container coated with TaC using new method: Ends tapped off,  with liquid poured in and swirled around entire container, then poured back out - 'flushing technique'

Container is wrapped with 3 x Ta heat shields, not incl center block.

Loaded into EVAP2 and currently pumping down.

 Tuesday, August 25, 2015, 13:52

IGP1 = 2.2e-6 Torr.

HS water valves opened.

No leaks detected.

Tapped up manually to 35A.

Vacuum stable.

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

Final setpoints for TGHT = 720A and TBHT = 230A, with final desired temp of 1800C

 Wednesday, August 26, 2015, 09:56

IGP1 = 8.8e-7 Torr.

TGHT = 260A, 3.0V

TBHT = 145A, 1.8V

Increasing ramping rate to 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Wednesday, August 26, 2015, 14:15

IGP1 = 3.5e-6 Torr.

TGHT = 720A, 11.3V

TBHT = 230A, 3.2V

DV = 5.48V

OMEGA RS [right side-old port] = 1745C

OMEGA LS [left side-new port] = 1880C

Tapping up manually to achieve 1800C on OMEGA RS

 Wednesday, August 26, 2015, 14:44

IGP1 = 3.7e-6 Torr.

TGHT = 748A, 11.9V

DV = 5.78V

OMEGA RS = 1803C

OMEGA LS = 1935C

Thursday, August 27, 2015, 07:31

 Remained at max setpoints for ~17hrs.

IGP1 = 1.3e-6 Torr.

DV = 5.79V

OMEGA RS = 1862 [this reading may not be correct due to the laser being moved at max setpoint - this temperature reading may be taken from a different location then the last reading]

OMEGA LS = 1955

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

Laura Lambert wrote:

Tuesday, August 25, 2015, 11:50 Container coated with TaC using new method: Ends tapped off,  with liquid poured in and swirled around entire container, then poured back out - 'flushing technique' Container is wrapped with 3 x Ta heat shields, not incl center block. Loaded into EVAP2 and currently pumping down.  Tuesday, August 25, 2015, 13:52 IGP1 = 2.2e-6 Torr. HS water valves opened. No leaks detected. Tapped up manually to 35A. Vacuum stable. Initiated auto ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints for TGHT = 720A and TBHT = 230A, with final desired temp of 1800C  Wednesday, August 26, 2015, 09:56 IGP1 = 8.8e-7 Torr. TGHT = 260A, 3.0V TBHT = 145A, 1.8V Increasing ramping rate to 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.  Wednesday, August 26, 2015, 14:15 IGP1 = 3.5e-6 Torr. TGHT = 720A, 11.3V TBHT = 230A, 3.2V DV = 5.48V OMEGA RS [right side-old port] = 1745C OMEGA LS [left side-new port] = 1880C Tapping up manually to achieve 1800C on OMEGA RS  Wednesday, August 26, 2015, 14:44 IGP1 = 3.7e-6 Torr. TGHT = 748A, 11.9V DV = 5.78V OMEGA RS = 1803C OMEGA LS = 1935C Thursday, August 27, 2015, 07:31  Remained at max setpoints for ~17hrs. IGP1 = 1.3e-6 Torr. DV = 5.79V OMEGA RS = 1862 [this reading may not be correct due to the laser being moved at max setpoint - this temperature reading may be taken from a different location then the last reading] OMEGA LS = 1955 Initiating auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Thursday, August 27, 2015, 16:34

Target is removed from the evaporator and inspected.  

The "flushing technique" has a much better result.  The inner coated surface is sintered well.  

John Wong wrote:

Wednesday, January 15, 2014, 17:30 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min.  TBHT will be ramped up to 230A at 0.2A/min.    Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)

 Thursday, January 16, 2014, 11:35

Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed.

TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop.

Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.

Laura Lambert wrote:

John Wong wrote:  Wednesday, January 15, 2014, 17:30 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min.  TBHT will be ramped up to 230A at 0.2A/min.    Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)     Thursday, January 16, 2014, 11:35 Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed. TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop. Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.

 Friday, January 17, 2014, 09:28

TGHT/TBHT @ 300/200A.  TBHT voltage is limited at 3A.  

TGHT ramping rate increased to 2A/min.  Pressure @ 4.5e-7 Torr.  

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote: John Wong wrote:  Wednesday, January 15, 2014, 17:30 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min.  TBHT will be ramped up to 230A at 0.2A/min.    Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)     Thursday, January 16, 2014, 11:35 Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed. TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop. Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.    Friday, January 17, 2014, 09:28 TGHT/TBHT @ 300/200A.  TBHT voltage is limited at 3A.   TGHT ramping rate increased to 2A/min.  Pressure @ 4.5e-7 Torr.      Friday, January 17, 2014, 10:14 TBHT stopped at 200A with voltage limit sitting at 3V. Aborted auto-ramp, changed the voltage limit to 5V and increased ramping rate to 2A/min. Re-started auto-ramp. IGP1 @ 5.0e-7 Torr

 Friday, January 17, 2014, 12:45

TGHT voltage limiting at 9.9V, and  current stayed at 560A.  Increased the TGHT voltage to 10.5V and continued ramping the heater up.

TGHT/TBHT stabilized at 580A (~10V) and 230A(3.6V). 

Pressure at 1.03e-6 Torr and coming down... 

Target will be heated until 5pm (4hrs) before cooling down at the ramping rate of 2A/min. 

Chamber will be vented in air, next week.

 Friday, January 17, 2014, 16:51

Auto-cooling initiated at 2A/min.

Vac @ 5.3e-7 Torr.

John Wong wrote:

Laura Lambert wrote: John Wong wrote: Laura Lambert wrote: John Wong wrote:  Wednesday, January 15, 2014, 17:30 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min.  TBHT will be ramped up to 230A at 0.2A/min.    Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)     Thursday, January 16, 2014, 11:35 Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed. TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop. Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.    Friday, January 17, 2014, 09:28 TGHT/TBHT @ 300/200A.  TBHT voltage is limited at 3A.   TGHT ramping rate increased to 2A/min.  Pressure @ 4.5e-7 Torr.      Friday, January 17, 2014, 10:14 TBHT stopped at 200A with voltage limit sitting at 3V. Aborted auto-ramp, changed the voltage limit to 5V and increased ramping rate to 2A/min. Re-started auto-ramp. IGP1 @ 5.0e-7 Torr  Friday, January 17, 2014, 12:45 TGHT voltage limiting at 9.9V, and  current stayed at 560A.  Increased the TGHT voltage to 10.5V and continued ramping the heater up. TGHT/TBHT stabilized at 850A (~10V) and 230A(3.6V).  Pressure at 1.03e-6 Torr and coming down...  Target will be heated until 5pm (4hrs) before cooling down at the ramping rate of 2A/min.  Chamber will be vented in air, next week.  Friday, January 17, 2014, 16:51 Auto-cooling initiated at 2A/min. Vac @ 5.3e-7 Torr.

 Wednesday, January 15, 2014, 17:30

Target container is coated with TaC.  No Ta-heat shields are used.

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

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

 Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.  

Notes: 

If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.  

Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory) 

John Wong wrote:

Laura Lambert wrote: John Wong wrote:  Wednesday, January 15, 2014, 17:30 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min.  TBHT will be ramped up to 230A at 0.2A/min.    Chamber is currently being pumped.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)     Thursday, January 16, 2014, 11:35 Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed. TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop. Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.    Friday, January 17, 2014, 09:28 TGHT/TBHT @ 300/200A.  TBHT voltage is limited at 3A.   TGHT ramping rate increased to 2A/min.  Pressure @ 4.5e-7 Torr.

 Friday, January 17, 2014, 10:14

TBHT stopped at 200A with voltage limit sitting at 3V.

Aborted auto-ramp, changed the voltage limit to 5V and increased ramping rate to 2A/min. Re-started auto-ramp.

IGP1 @ 5.0e-7 Torr

 Monday, June 29, 2015, 16:17

Target container is coated with TaC. No Ta-heat shields are used.

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

TBHT will be ramped up to 230A at 01A/min.

Chamber is currently being pumped down.

Laura Lambert wrote:

Monday, June 29, 2015, 16:17 Target container is coated with TaC. No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min. TBHT will be ramped up to 230A at 01A/min. Chamber is currently being pumped down.

 Monday, June 29, 2015, 23:37

Opened the HS valves around 5pm.  Small leaks or just a vibration in the pipe line caused a rise in vacuum.  Leak rate is small, so allow the chamber to continue to pump down over night.

Sintering process can begin tomorrow if vacuum is allowed.

John Wong wrote:

Laura Lambert wrote:  Monday, June 29, 2015, 16:17 Target container is coated with TaC. No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min. TBHT will be ramped up to 230A at 01A/min. Chamber is currently being pumped down.    Monday, June 29, 2015, 23:37 Opened the HS valves around 5pm.  Small leaks or just a vibration in the pipe line caused a rise in vacuum.  Leak rate is small, so allow the chamber to continue to pump down over night. Sintering process can begin tomorrow if vacuum is allowed.

 Tuesday, June 30, 2015, 08:22

IGP1 = 3.6e-7 Torr.

Tapped up manually to 40A.

Vacuum looks good.

IGP1 = 6.9e-7 Torr.

Inititating auto-ramp...

 Thursday, July 02, 2015, 09:56

IGP1 = 8.9e-7 Torr.

OMEGA = 1728C

TGHT and TBHT = 580A and 230A respectively.

Tapping up manually to 1800C.

 Thursday, July 02, 2015, 11:02

TGHT = 615A, 10.9V

OMEGA = 1800C

IGP1 = 1.1e-6 Torr.

Will continue to heat for 4hrs.

 Thursday, July 02, 2015, 15:43

Target container remained at 1800C for 4hrs50min.

Initiating auto-cool for TGHT = 2A/min and TBHT = 1A/min.

 Friday, July 03, 2015, 08:24

Vented in air and opened up this morning.

Edge of container on both ends not fully sintered [see photos]

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote:  Monday, June 29, 2015, 16:17 Target container is coated with TaC. No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min. TBHT will be ramped up to 230A at 01A/min. Chamber is currently being pumped down.    Monday, June 29, 2015, 23:37 Opened the HS valves around 5pm.  Small leaks or just a vibration in the pipe line caused a rise in vacuum.  Leak rate is small, so allow the chamber to continue to pump down over night. Sintering process can begin tomorrow if vacuum is allowed.    Tuesday, June 30, 2015, 08:22 IGP1 = 3.6e-7 Torr. Tapped up manually to 40A. Vacuum looks good. IGP1 = 6.9e-7 Torr. Inititating auto-ramp...  Thursday, July 02, 2015, 09:56 IGP1 = 8.9e-7 Torr. OMEGA = 1728C TGHT and TBHT = 580A and 230A respectively. Tapping up manually to 1800C.  Thursday, July 02, 2015, 11:02 TGHT = 615A, 10.9V OMEGA = 1800C IGP1 = 1.1e-6 Torr. Will continue to heat for 4hrs.  Thursday, July 02, 2015, 15:43 Target container remained at 1800C for 4hrs50min. Initiating auto-cool for TGHT = 2A/min and TBHT = 1A/min.  Friday, July 03, 2015, 08:24 Vented in air and opened up this morning. Edge of container on both ends not fully sintered [see photos]

 Monday, July 06, 2015, 11:54

Inner tube surface isn't homogeneously sintered with TaC (see attachment).  

A second coating may help.  

For the re-sintering process, the target container will be wrapped with 6.2cm Ta (width) foil as a layer for heat shield on each side of the tube,  excluding the centre block - just like the same process was done last time, see e-log ID#217.  

The Ta-foil and the target tube will be spaced with Ta wire coiled around it.  

TGHT can be ramped up about 520A/9.1V to achieve 1900C.  Heating time for 3-4 hours until vacuum comes down to low 10-6 Torr.