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. 

John Wong wrote:

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.

 Monday, July 06, 2015, 16:28

Container has been re-coated with TaC.

Target container is wrapped with a single 15.5cm x 8.5cm Ta foil heat shield on each side of the center block, spaced with Ta wire coil.

Chamber is currently being pumped down.

 Tuesday, July 07, 2015, 09:36

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

IGP1 = 6e-7 Torr.

Tapped up manually to 30A.

Waited ~1hr.

Vacuum stable, IGP1 = 1.9e-6 Torr.

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

 Target container reached max setpoints of 520A/230A and 1950C ~6hrs ago.

IGP1 = 7.6e-7 Torr.

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

 Friday, July 10, 2015, 11:16

Vented in air and removed from evap2.

Again, edges not fully sintered [see photos]

Inside of container looks better, fully coated.

Wednesday, July 23, 2014, 15:07

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 down

 Wednesday, July 23, 2014, 17:40

Vacuum came down to mid 10-6 Torr.

Stepped up TGHT and TBHT to 30A - IG1 @ 1.4e-5 Torr.

Initiated auto-ramping.

 Thursday, July 24, 2014, 17:19

TGHT and TBHT have reached to 100A, and vacuum is coming down to 1.4e-6 Torr.

Increase ramping rate, TGHT to 1A/min, TBHT 0.5A/min.

 Friday, July 25, 2014, 11:26

Target container temperature reaches ~1550C at 580A on TGHT and 230A TBHT, and it has been heated for ~10 hrs.

Auto-cooling initiated at 2A/min.

John Wong wrote:

Wednesday, July 23, 2014, 15:07 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 down  Wednesday, July 23, 2014, 17:40 Vacuum came down to mid 10-6 Torr. Stepped up TGHT and TBHT to 30A - IG1 @ 1.4e-5 Torr. Initiated auto-ramping.  Thursday, July 24, 2014, 17:19 TGHT and TBHT have reached to 100A, and vacuum is coming down to 1.4e-6 Torr. Increase ramping rate, TGHT to 1A/min, TBHT 0.5A/min.  Friday, July 25, 2014, 11:26 Target container temperature reaches ~1550C at 580A on TGHT and 230A TBHT, and it has been heated for ~10 hrs. Auto-cooling initiated at 2A/min.

 Monday, July 28, 2014, 10:50

vented in air and opened this morning. successful run

Tuesday, July 17, 2012, 15:45

Target boat is filled with TaC coated regular- and D-endcaps. 

The boat is wrapped with a Ta heat-shield. 

Chamber is being pumped down, currently at 5e-6 Torr.

Tuesday, July 17, 2012, 15:58

Heat-shield cooling water valve opened; no leaks detected.

Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.

 Wednesday, July 18, 2012, 10:44

Yesterday evening, the target heater tripped off a few times due to high vacuum excursion.  The TGHT ramping rate was low to 0.2A/min.  The current was ramped up sturdily to 500A this morning.  

Wednesday, July 18, 2012, 10:46

Increased ramping rate to 2A/min.  Vacuum currently at 2.2e-6 Torr.

 Wednesday, July 18, 2012, 16:18

TGHt has reached to 580A and stayed for about 5 hrs. 

Cooling down in process...  2A/min for TGHT --> 0A.

 Thursday, July 19, 2012, 10:31

TGHT reached to 0A. 

Evaporator is off. 

Venting chamber... 

Tuesday, August 27, 2013, 16:48

Target boat is filled with TaC coated endcaps (brown) and some partial sinterred ones (gray) from before.  (see attachment#1).

The container is wrapped with Ta heat-shield.

Chamber has been pumped down; IG currently @ 7.3e-7 Torr. 

Heat-shield cooling water valves are open; no leaks are detected.

Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.

 Wednesday, August 28, 2013, 16:09

TGHT has reached to 580A and been heated for over 4 hours.

IG is coming down, currently at 1.9 e-6 Torr.

Initiated auto-cooling.  2A/min. 

John Wong wrote:

Tuesday, August 27, 2013, 16:48 Target boat is filled with TaC coated endcaps (brown) and some partial sinterred ones (gray) from before.  (see attachment#1). The container is wrapped with Ta heat-shield. Chamber has been pumped down; IG currently @ 7.3e-7 Torr.  Heat-shield cooling water valves are open; no leaks are detected. Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.  Wednesday, August 28, 2013, 16:09 TGHT has reached to 580A and been heated for over 4 hours. IG is coming down, currently at 1.9 e-6 Torr. Initiated auto-cooling.  2A/min.

 Thursday, August 29, 2013, 11:50

TGHT at 0 A

IG at 3.5e-7 Torr

Turning off EVAP2 and venting chamber

Process complete

Tuesday, May 28, 2013, 17:36

The target containers endcaps were coated with TaC solution and let dry. 

Each cap is wrapped with a small piece of graphite foil and inserted in the target boat.

The chamber is currently being pumped down. 

The HS cooling water valve will be opened tomorrow; any leak will be inspected.

When the vacuum is good,  TGHT will be ramped up to 580A. 

 Wednesday, May 29, 2013, 17:06

HS water valve was opened early this morning; no leaks were detected.

TGHT has stepped up to 50A.  IG is currently at 2.0e-6Torr. 

Initiated auto-ramping at 1.0A/min.

 Thursday, May 30, 2013, 11:12

TGHT reached to 580.  The end caps have been heated at that current for more than 7 hrs.

IG is coming down, currently at 8e-7 Torr.

Auto-cooling initiated, ramping down at 2A/min .

 Tuesday, January 28, 2014, 15:43

The target containers end-caps were coated with TaC spray and let dry.

Each cap is wrapped with a small piece of graphite foil and inserted in the target boat. [see attached photo]

The chamber is currently being pumped down overnight.

 Wednesday, January 29, 2014, 11:32

Chamber was pumped down to 1.6e-7 Torr overnight.

HS cooling water valve opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 11.05V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 580A.

Good vacuum: 3.00e-5 Torr, Bad vacuum 4.00e-5 Torr.

 Thursday, January 30, 2014, 09:06

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 2.4e-7 Torr, TGHT = 283A; stepping ramping rate up to 2.0A/min.

 Thursday, January 30, 2014, 15:53

TGHT reached 580A at 11:45. Measured temp @1650C.

Initiating TGHT auto-cooling now at 2.0A/min.

 Friday, January 31, 2014, 09:04

Chamber cooled down overnight, vented and opened this morning.

Smooth run!

 Friday, January 31, 2014, 11:21

Opened up the end caps, turns out it wasn't such a smooth run...they're not fully sintered 

See attached photo comparison between fully sintered end cap [silver] and end cap from this run [green].

Will re-install and re-sinter next week.

 Wednesday, February 05, 2014, 11:34

End-caps re-installed into EVAP2

Target boat is wrapped with 3 x Ta heat-shield.

Chamber is currently being pumped down.

 Wednesday, February 05, 2014, 14:31

Chamber was pumped down to 5e-7 Torr this morning.

HS cooling water valve opened, no leaks detected.

TGHT was stepped up to 35A, voltage max set at 11.05V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 580A.

Good Vacuum: 3.00e-5 Torr, Bad vacuum 4.00e-5 Torr.

 Thursday, February 06, 2014, 09:06

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 1.1e-7 Torr, TGHT = 259A; stepping ramping rate up to 2.0A/min.

 Friday, February 07, 2014, 10:10

TGHT reached 580A yesterday. Measured internal temp @ 1500C.

Initiated TGHT auto-cooling this morning at 2.0A/min

 Tuesday, February 11, 2014, 13:30

Vented and opened chamber this morning.

Endcaps are toast  [see pictures attached]

Some of the endcaps broke/fried, others deformed-none useable.

Possibly due to new target boat resulting in more current?

Too much heat with Ta heat shields?

Bad News Bears 

 Tuesday, February 25, 2014, 16:08

The target containers end-caps were coated with TaC spray and let dry.

The caps are inserted in the target boat vertically with no heat shield and no graphite foil. [see attached photo]

The chamber is currently being pumped down overnight.

 Wednesday, February 26, 2014, 09:54

Chamber was pumped down overnight to 4.2e-7 Torr.

HS cooling water valves opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 14V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 700A.

Will ramp up to 700A rather than the usual 580A due to last round of endcaps not fully sintering at 580A with new target boat design.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Thursday, February 27, 2014, 09:38

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 2.8e-7 Torr; TGHT = 311A, 4.3V

Stepping ramping rate up to 2.0A/min.

 Friday, February 28, 2014, 08:53

TGHT reached max setpoint of 700A yesterday evening.

Internal temp measured with Mikron = 1700C

IGP1 = 3e-7 Torr 

Power = 12.95V

Initiating auto-cooling at 2.0A/min.

 Monday, March 03, 2014, 11:46

Vented and opened chamber this morning.

End caps not fully sintered! 

See attached photo comparison of fully sintered [grey], partially sintered from this round [light green] and pre-sinter [dark green].

Will not bother re-sintering, as partial sinter is enough.

 Friday, March 07, 2014, 11:41

The target container end-caps were sintered previously, but did not fully complete the sintering process [See elog entry # 119 EVAP2]

The caps are inserted in the target boat wrapped in graphite foils with 3 x Ta-heat shields.

The chamber was pumped down overnight.

IGP1 = 2e-7 Torr

HS cooling water valves were opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 9.05V. TBHT currently at 0A.

 Friday, March 07, 2014, 11:52

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.5A/min and max setpoint to 500A.

Will ramp to 500A due to last failed round of end caps breaking with 3-ta heat shields at 580A.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Friday, March 07, 2014, 13:21

IGP1 = 8e-7 Torr.

TGHT = 72A

Vacuum stable; therefore, increasing ramping rate up to 1.0A/min

 Friday, March 07, 2014, 14:20

IGP1 = 9.8e-7 Torr

TGHT = 130A

Vacuum stable; therefore, increasing ramping rate up to 2.0A/min

Laura Lambert wrote:

Friday, March 07, 2014, 11:41 The target container end-caps were sintered previously, but did not fully complete the sintering process [See elog entry # 119 EVAP2] The caps are inserted in the target boat wrapped in graphite foils with 3 x Ta-heat shields. The chamber was pumped down overnight. IGP1 = 2e-7 Torr HS cooling water valves were opened; no leaks detected. TGHT was stepped up to 35A, voltage max set at 9.05V. TBHT currently at 0A.  Friday, March 07, 2014, 11:52 Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.5A/min and max setpoint to 500A. Will ramp to 500A due to last failed round of end caps breaking with 3-ta heat shields at 580A. Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.  Friday, March 07, 2014, 13:21 IGP1 = 8e-7 Torr. TGHT = 72A Vacuum stable; therefore, increasing ramping rate up to 1.0A/min  Friday, March 07, 2014, 14:20 IGP1 = 9.8e-7 Torr TGHT = 130A Vacuum stable; therefore, increasing ramping rate up to 2.0A/min

Friday, March 07, 2014, 22:22  

Target current was at 500A before it tripped off on the chiller.   Tried to reset the chiller but to no avail.  Don't know what is going on yet. 

The TGHT/TBHT cooling water is still on, and this should OK while the HOT target boat is cooling down at the moment. 

Will leave it for now and further investigate on Monday

 Tuesday, August 05, 2014, 12:02

The target container end caps were coated with TaC spray and let dry.

The caps are inserted in the target boat vertically, wrapped in graphite foil with 3 x Ta-heat shield. [see attached photo]

The chamber is currently being pumped down.

Laura Lambert wrote:

Tuesday, August 05, 2014, 12:02 The target container end caps were coated with TaC spray and let dry. The caps are inserted in the target boat vertically, wrapped in graphite foil with 3 x Ta-heat shield. [see attached photo] The chamber is currently being pumped down.

 Tuesday, August 05, 2014, 17:19

HS water valve opened; no leaks detected. 

Pressure @ 2.5e-6 Torr.

Ramping up TGHT to 580A @ 1A/min.

John Wong wrote:

Laura Lambert wrote:  Tuesday, August 05, 2014, 12:02 The target container end caps were coated with TaC spray and let dry. The caps are inserted in the target boat vertically, wrapped in graphite foil with 3 x Ta-heat shield. [see attached photo] The chamber is currently being pumped down.    Tuesday, August 05, 2014, 17:19 HS water valve opened; no leaks detected.  Pressure @ 2.5e-6 Torr. Ramping up TGHT to 580A @ 1A/min.

 Thursday, August 07, 2014, 08:11

Yesterday the target boat was taken out.

The boat broke as it turns out it was used for a Niobium target and therefore wasn't coated with TaC.

The end caps were fully sintered.

 Thursday, September 11, 2014, 13:14

The target container end caps were coated with TaC spray and let dry.

The caps are inserted in the target boat wrapped in graphite foil with 3 x Ta-heat shields.

The chamber is currently pumping down.

 Friday, September 12, 2014, 14:17

Chamber was pumped down overnight.

HS cooling water valves opened, no leaks detected.

IGP1 = 7.2e-7 Torr.

TGHT stepped up to 35A, TBHT at 0A.

Waited ~30min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min.

Will ramp TGHT to 580A with a max 10V.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Monday, September 15, 2014, 11:31

TGHT stopped at 500A due to not high enough voltage max.

Increased max voltage to 12V

 Monday, September 15, 2014, 14:17

IGP1 = 6.3e-7 Torr

Increasing ramping rate to 1.0A/min

 Tuesday, September 16, 2014, 09:04

TGHT reached 577A and finished auto-ramping, then proceeded to drop down to 560A overnight.

Increased max voltage to 13.05A and TGHT to 580A.

 Tuesday, September 16, 2014, 13:52

TGHT reached 580A and sat there for ~5hrs.

IGP1 = 6.1e-7 Torr.

Initiating auto-cool at 2.0A/min.

 Wednesday, September 17, 2014, 13:03

Vented in air.

Opened up....looked 'deceivingly' ok.

then i took a layer of Ta off....grrrr  

the 1st layer of Ta was holding the boat together. as soon as that layer was taken off the target boat broke.

see attached photos.