Laura Lambert wrote:

Tuesday, September 23, 2014, 15:00 A new target boat [new design with no end caps] was sprayed with TaC coating and let dry. The target boat is wrapped with 3-layers of Ta-heat shield. The boat was installed in EVAP2, chamber is currently being pumped down.

 Tuesday, September 23, 2014, 18:31

Chamber was pumped down to 2.5e-6 Torr. 

HS water valve open; no leaks detected.

Stepping up TGHT to 40A - pressure is increasing...

 Tuesday, September 23, 2014, 19:05

Auto-ramping TGHT to 580A at 0.5A/min.  Temperature will be measured and TGHt will be adjusted accordingly.

 Wednesday, September 24, 2014, 11:57

Pressure is stable at 2.2-6 Torr as TGHT is ramping up.  Increase ramping rate to 2.0A/min.  Currently TGHT at 540A.

 Wednesday, September 24, 2014, 15:36

TGHT at 580A for 2 hrs.  Inner tube temp (left side wall, viewing from the window port) ~1800C (measured with Mikron = 1550C +250C em. correction); Vac @ 1.67e-6 Torr.

Temperature measurement distance from the window to Mikron = 45cm.

Increase TGHT to reach 2000C (Mikron @ 1750C)

 Wednesday, September 24, 2014, 18:14

TGHT has gone up to 725A/13.2V.  Temp measured at 1740C (+250C = ~2000C).  Pressure gone up to 5.5e-6 Torr and it's coming down slowly.

Will continue heating at this temperature for a few hours; then cool down afterward.

 Wednesday, September 24, 2014, 18:56

Temperature is pretty stable at 1740C on Mikron, and pressure is still coming down, currently at 2.9e-6 Torr.

Slow ramping down TGHT at 1.0A/min.  The chamber should be ready for venting tomorrow. 

Target boat will be inspected.

 Thursday, September 25, 2014, 17:25.

The boat was inspected and it turned out great!  The coating was fully sintered and there is no sign of damage on the boat. 

See the link for photos.

https://www.dropbox.com/sh/m7ycqhkj4avfull/AABHVTweTsP4ajeWZ6uoY010a?dl=0

Thursday, September 25, 2014, 17:32

Target boat is filled with Ta-coated endcaps.  The caps are stacked together.  In between each cap, a piece of graphite foil is used for separation so the Ta caps would not fused. 

See link for photos:

https://www.dropbox.com/sh/rydtdho6ggh4l3l/AAAYmvqT0mVQ_pnz4iecS4ksa?dl=0

The boat is wrapped with 3-layers of heatshields.  The chamber is currently being pumped down.

TGHT will be ramped up to 580A and the temperature will be measured.

Monday, September 29, 2014, 11:12

TGHt was stepped up to 40A on last Friday and chamber continues to pump down over the weekend.

Vac @ 2.56e-6 Torr, mp @ 19mTorr.

Ramping up TGHT 580A at 1.0A/min.

 Monday, September 29, 2014, 11:50

TGHT tripped off at 53A.  Reduce ramping rate to 0.5A/min for now.

 Monday, September 29, 2014, 16:17

Vacuum is coming down to 9.5e-7 Torr.  Increased ramping rate to 1.0A/min.

 Tuesday, September 30, 2014, 11:59

TGHT reached to 580A/10.18V.  Target has been heated at that current for almost 12 hrs. Vac @ 4.9e-7 Torr.

Local temp measured with Mikron = (1500C + 250 C correction) = 1750C

Cooling down at 2A/min.

 Thursday, October 02, 2014, 11:13

The coating is fully sintered; no sign of any damage on the endcaps.  

Process is successful.  

 Thursday, October 02, 2014, 11:22

It was found that after the last process, Evap#2 has broken insulators - the cylinder insulator that supports the target centre legs and the block insulator that supports the terminals.  

Informed Anders/Rick.

Laura Lambert wrote:

Thursday, October 02, 2014, 11:51 Target container sprayed with TaC, currently drying in fume hood  Monday, October 06, 2014, 12:11 Target container & back block is wrapped with 3 layers of Ta-heat shield.  The chamber has been pumped down over the weekend.  Pressure currently at 2.23e-7 Torr.  HS water valves open; no leaks detected. TGHT will be ramped up to 580A at 0.2A/min TBHT will be ramped up to 230A at 0.2A/min.

 Monday, October 06, 2014, 12:16

Stepped up both TGHT/TBHT to 35A. 

Tuesday, October 07, 2014, 12:54

TBHT reached to 230A/3.7V and TGHT is still ramping up, currently at 303A/4.5V. Temp measured with Omega-IR2 = 1165C with e'=0.85

Pressure @ 5.2e-7 Torr. 

Increase ramping rate to 2A/min.

 Tuesday, October 07, 2014, 16:21

TGHT is now at 580A and TGHT at 230A.

Temperature is measured with OMEGA-IR2, MIKRON, and analog pyrometer - All the measurements are agreed at 1700C (without the tantalum emissivity correction of 250C)

The OMEGA-IR2 slope has changed to 0.97 for the correction - The real temperature reading from the display is showing 1935C.

Now... attempting to low TBHT to see any temperature change.

 Tuesday, October 07, 2014, 17:01

TGHT @ 580A.

TBHT = 180C, Temp = 1925C

TBHT = 130C, Temp = 1920C

Not much of change in the temperature on the target tube...

Tuesday, October 07, 2014, 17:07

Attempting to increase the temperature to 2000C

TGHT = 600A, Temp = 1955C

TGHT = 620A, Temp = 2000C

Target will continue heating at this temperature overnight... Will continue to monitor.

 Tuesday, October 07, 2014, 20:59

After almost 4 hours of heating at 620A on TGHT, the temperature has dropped to 1980C.  

Pressure is coming down to 1.17e-6 Torr.  

Increased TGHT to 630A to maintain temp @ 2000C

Thursday, October 09, 2014, 15:56

The target boat contains 5 samples of Nb discs.  Each disc is wrapped with Nb foil and labelled. 

Samples will be heated up to 1400C for 4 hours. 

chamber has been pumped down to 3.9e-6 Torr. HS valves open - no leaks detected.

Ramping up TGHT...

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote:  Thursday, October 02, 2014, 11:51 Target container sprayed with TaC, currently drying in fume hood  Monday, October 06, 2014, 12:11 Target container & back block is wrapped with 3 layers of Ta-heat shield.  The chamber has been pumped down over the weekend.  Pressure currently at 2.23e-7 Torr.  HS water valves open; no leaks detected. TGHT will be ramped up to 580A at 0.2A/min TBHT will be ramped up to 230A at 0.2A/min.    Monday, October 06, 2014, 12:16 Stepped up both TGHT/TBHT to 35A.  Tuesday, October 07, 2014, 12:54 TBHT reached to 230A/3.7V and TGHT is still ramping up, currently at 303A/4.5V. Temp measured with Omega-IR2 = 1165C with e'=0.85 Pressure @ 5.2e-7 Torr.  Increase ramping rate to 2A/min.  Tuesday, October 07, 2014, 16:21 TGHT is now at 580A and TGHT at 230A. Temperature is measured with OMEGA-IR2, MIKRON, and analog pyrometer - All the measurements are agreed at 1700C (without the tantalum emissivity correction of 250C) The OMEGA-IR2 slope has changed to 0.97 for the correction - The real temperature reading from the display is showing 1935C. Now... attempting to low TBHT to see any temperature change.  Tuesday, October 07, 2014, 17:01 TGHT @ 580A. TBHT = 180C, Temp = 1925C TBHT = 130C, Temp = 1920C Not much of change in the temperature on the target tube... Tuesday, October 07, 2014, 17:07 Attempting to increase the temperature to 2000C TGHT = 600A, Temp = 1955C TGHT = 620A, Temp = 2000C Target will continue heating at this temperature overnight... Will continue to monitor.  Tuesday, October 07, 2014, 20:59 After almost 4 hours of heating at 620A on TGHT, the temperature has dropped to 1980C.   Pressure is coming down to 1.17e-6 Torr.   Increased TGHT to 630A to maintain temp @ 2000C    Wednesday, October 08, 2014, 11:46 Temperature readout from omega-IR2C = 2054C TGHT = 11.14V, 628.0A TBHT = 2.01V, 129.8A IGP1 = 8.2e-7Torr Initiating auto-cool for TGHT @ 2A/min, TBHT @ 1A/min  Thursday, October 09, 2014, 16:00 vented in air and opened up this morning target container looks good!

 Thursday, October 09, 2014, 16:36

Photos for the OMEGA-IR2C temp measurement can be found on this link (see also the subfolder for the heating process):

https://www.dropbox.com/sh/n5sxcepg7e847xw/AACMubuKW1idd49D1Nz_0diNa?dl=0

Thursday, October 09, 2014, 17:36

Target boat consists of 5 Nb discs.  Each disc is wrapped with Nb foil, and to be heated to 1400C for 4 hours.

Chamber has been pumped down to 6.5e-7 Torr.  HS valves open - no leaks detected.

TGHT has ramped to 330A to maintain the 1400C temperature. 

At 21:30, the target will be cooled down.

Temperature can be monitored from this link:

https://www.dropbox.com/sh/kor6gnutnlimqxw/AAAee2yb-Hj3JEbBysrAW2oYa?dl=0

 Thursday, October 09, 2014, 22:48

Samples have been heated at 1420C for over 4 hours.  

Pressure at 6.6 e-7 Torr. 

Cooling process initiated, ramping down at 2A/min. 

 Friday, October 10, 2014, 13:50

Samples were successfully conditions; no signs of any damage.

Tuesday, November 04, 2014, 16:08

The purpose of this experiment is to improve the fabrication of SiC.  Previously, the SiC target was heated to 2000c and yellow crystals were observed.

In this experiment, 10g of SiC powder (7um size) was previously milled down (actual size to be determined under SEM).  The powder was mixed with 5% PVA and the slurry was pour onto a glass and let dry.  The semi-dry slurry was rolled up into balls. The SiC balls were let dry in over (115C) over night. Taken out 2.903g SiC + 5% PVA, it's rolled up with a small sheet of graphite foil.  Then the targer boat is filled with the sample and wrapped with 3-layers of Ta-heat shield.

The sample will be heated up to 2000C to see if the yellow crystals are reproducible.  It is suspected that there might be a phase transformation from 6H alpha-SiC to 3C beta-SiC. 

Chamber is currently being pumped down... 

Wednesday, November 05, 2014, 14:04

TGHT was ramped up over night, currently at 485A = 1800 C. 

Will do manual step up to get to 2000C. 

Laura Lambert wrote:

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

 Tuesday, November 04, 2014, 15:59

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

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

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

More study needs to be done... 

See elog # 168.

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

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

Monday, February 02, 2015, 16:28

Container is coated with TaC.  No Ta foil wrapped around. 

Chamber is being pumped down.

TGHT/TBHT will be ramped up to 580A/230A at 0.2A/min.

Laura Lambert wrote:

John Wong wrote: Monday, February 02, 2015, 16:28 Container is coated with TaC.  No Ta foil wrapped around.  Chamber is being pumped down. TGHT/TBHT will be ramped up to 580A/230A at 0.2A/min.      Tuesday, February 03, 2015, 10:28 HS water valves opened; no leaks detected. IGP1 = 5.9e-7 Torr  Wednesday, February 04, 2015, 11:10 attempted to initiate manual ramp up of TGHT and TBHT yesterday, but not responding to EPICS currently sitting under vacuum, waiting on fix...  Wednesday, February 04, 2015, 14:16 controls fixed. initiated auto-ramp.  Thursday, February 05, 2015, 08:56 IGP1 = 4.1e-7 Torr TGHT = 290A TBHT = 225A Increasing auto-ramp to 1.0A/min  Thursday, February 05, 2015, 13:49 IGP1 = 1.4e-6 Torr TGHT = 569A TBHT = 232A Increasing auto-ramp to 2.0A/min

 Thursday, February 05, 2015, 18:02

Auto-cooling TGHT to 400A at 1A/min.  Need to take voltage reading tomorrow. 

Laura Lambert wrote:

Monday, March 09, 2015, 16:47 Target consists of 400 discs. Total packed length 3.4cm Total mass 45.8181g Re foil inserted. Chamber is currently being pumped down. No Ta-heat shield wrapped. One end-cap inserted on left (wrt ionizer into the page) TGHT and TBHT will be ramped up to 820A/230A respectively at 2.0A/min.  Tuesday, March 10, 2015, 10:28 HS water valves opened, no leaks detected. IGP1 = 4.5e-7 Torr. Power supply not responding to epics...AGAIN. grrrr  Tuesday, March 10, 2015, 13:17   IOC was rebooted - back up and running again! yay!  IGP1 = 4.0e-7 Torr. Tapped up manually to 35A, waited ~30min, vaccuum stable. Initiating auto-ramp. Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr.  Wednesday, March 11, 2015, 09:11 Target has been at max setpoints for ~14hrs. OMEGA = 1472C TGHT = 820A, 12.85V TBHT = 230A, 3.696V IGP1 = 5.5ee-7 Torr Manually tapping up to obtain hotter internal temperature...  Wednesday, March 11, 2015, 11:33 Current conditions: OMEGA = 1565C TGHT = 900A, 14.3V TBHT = 230A, 3.7V IGP1 = 6.3e-7 Torr Digital pyrometer readings: Hottest point on left leg, WRT ionizer tube into page = 2400C Internal temp of container = 1580C Sat at this temperature ~45min. Initiating auto-cool at TGHT 2.0A/min, TBHT 1.0A/min [See attached photo for collected data]  Thursday, March 12, 2015, 13:12 vented and opened up this morning. only reached a max internal temp of 1580C. therefore added 3xTa heat shield and will re-condition at a higher temp. currently pumping back down.  Thursday, March 12, 2015, 14:34 IGP1 = 7.0e-7 Torr stepped up to 35A, waited ~30min, vacuum stable. IGP1 = 6.1e-7 Torr Initating ramp-up...  Friday, March 13, 2015, 07:47 IGP1 = 2.9e-7 Torr reached max set points for TGHT = 600A, TBHT = 230A Initiating manual tap-up.  Friday, March 13, 2015, 10:31 Reached 720A, 1800C at 0850 Will continue to heat for ~3hrs [see attachment for collected data]  Friday, March 13, 2015, 12:00 Sat at max temperature, 1800C, for 3 hours. Initiating auto-cool at 2.0A/min for TGHT and 1.0A/min for TBHT.

 Monday, March 16, 2015, 17:30

Target was removed from Evap#2.  It was successfully conditioned. 

The other end cap was inserted and expended. 

Standard salts were added.   And Re foil is inserted. 

Target is ready for assembly.

Laura Lambert wrote:

Friday, April 17, 2015, 16:01 Total number of foils: 520 discs Total mass of materials [incl graphite foils]: 60.2441g Total length packed: 17.0cm Container is wrapped with 3x Ta-heat shields. No endcaps inserted to allow outgasing. Currently being pumped down.  Monday, April 20, 2015, 11:08 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 over the weekend. IGP1 = 2.1e-7 Torr. HS cooling water valves opened; no leaks detected. TGHT max voltage = 18V, TBHT max voltage = 5V .... attempted to start stepping up manually. power supply not responding to epics controls for TBHT only...looking into problems now...  Monday, April 20, 2015, 16:06 Epics is working. Power supply connections unplugged/plugged back in. Everything working again. Tapped up manually to 40A. Waited ~1hr30 for vacuum to stabilize. IGP1 = 1.8e-6 Torr. Good vac = 3e-5 Torr. Bad vac = 4e-5 Torr. TGHT and TBHT will be ramped up to 820A and 230A, respectively. Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively.  Wednesday, April 22, 2015, 15:23 TGHT = 200A, 2.26V; TBHT = 117A, 1.58V IGP1 = 9.8e-6 Torr. Increasing auto-ramp to 0.4A/min and 0.2A/min for the TGHT and TBHT respectively.

 Thursday, April 23, 2015, 10:15

Vac at 2.e-6 Torr.  Increased TGHT ramping rate to 1.0A/min.  Current temperature at 1443C, TGHT at 641A, TBHT at 230A.

 Thursday, April 23, 2015, 15:02

Evap#2 window for the temp reader is now coated, so temp reading is not available.  (see attachment). 

TGHT has been at 820A/13.45V for almost 2 hours, will continue to heat at this current for a few more hours.  Will initiate the cooling process from home…  

 Thursday, April 23, 2015, 22:31

Target has been heated at 820A for about 9.5hrs.  Current vacuum at 4.7e-7 Torr.

Initiating cooling process at -2A/min for TGHT and -1A/min for TBHT.

Friday, April 24, 2015, 10:13  

Target has been cooled at 0A for about 5 hours.  Chamber is currently being vented and the target will be taken out for inspection.

Friday, April 24, 2015, 12:37  

The target was inspected.  

Some yellow crystals were form around the ends but they were easily removed this time.  

With both ends open during the sintering process and shorten the target length with 1cm space of both side, the target is looking a lot better.  

 No visible damage on the target surface.  

Inside, the channel has a clear pathway, and the discs are nicely aligned.  

End caps and Rh foils are inserted - It's ready for assembly.

See link for pics after the sintering process.

https://www.dropbox.com/sh/w5k4l3fezfat2cm/AAAyX67zyUPUVvN_WzEHFXM2a?dl=0

Laura Lambert wrote:

Friday, May 01, 2015, 10:27 Four different samples of ZrC are loaded into a target boat. Sample A: ZrC + NO graphite / hand cut Sample B: ZrC + NO graphite / laser cut Sample C: ZrC + graphite / hand cut Sample D: ZrC + graphite / laser cut A picture showing the different samples is attached [one face-up/ one face-down sample of each side-by-side] Each sample consists of ~20-25 discs, stacked together and wrapped in graphite sheet [see attachment for photo] The target boat is wrapped with 3 x Ta heat shield. EVAP1 pumped down overnight. HS water valves were opened this morning, no leaks detected. IGP1 = 5.5e-7 Torr. Tapping up TGHT manually to 30A...  Friday, May 01, 2015, 10:54 Tapped up manually to 30A. Over the course of 20min the vacuum climbed to IGP1 = 1.0 e-5 Torr. Backed off TGHT to 20A to allow vacuum to stabilize. Waited ~10min. Vacuum dropped to IGP1 = 6.5e-6 Torr. Tapped back-up manually to 30A. Waited ~45min. Vacuum stable, IGP1 = 1.2e-5 Torr. Initiating auto-ramp at 0.1A/min for the TGHT with a max setpoint of 300A / 5.00V. Good Vacuum = 3.00e-5 Torr. Bad vacuum = 4.00e-5 Torr.  Monday, May 04, 2015, 11:17 IGP1 = 2e-7 Torr. TGHT = 274A, 4.75V Ramp-up limited to 275A due to max voltage being set at 5.0V Increased max voltage to 10V Tapping up manually to 1800C and recording data.

 Monday, May 04, 2015, 17:24

Samples have been heated at 1800C for >2 hours. 

Vaccum at 4.3e-7 Torr, TGHT 475A/9.1V. (Direct Vol = 5.3V).

Initiated cooling down process.  Chamber will be vented tomorrow.

 Tuesday, May 05, 2015, 10:22

TGHT reached to 0A. Chamber has already vented. 

Samples will be taken out for examination.

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. 

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.

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.

Laura Lambert wrote:

Friday, May 29, 2015, 11:21 Total number of foils: 425 discs Total mass of materials [incl graphite foils]: 44.41g Total length packed: 12.3cm Container has no heat shields. No endcaps inserted to allow outgassing. Currently being pumped down.  Friday, May 29, 2015, 14:13 HS water valves opened, no leaks detected. IGP1 = 5.4e-6 Torr. Tapping up manually. Friday, May 29, 2015, 16:48 Tapped up manually to 20A. IGP1 = 5.9e-6 Torr. Initiating auto-ramp at 0.2A/min for the TGHT and 0.1A/min for the TBHT. Max setpoints set to 580A and 230A for the TGHT and TBHT respectively. Good Vacuum = 3.0e-5 Torr. Bad Vacuum = 4.0e-5 Torr.  Monday, June 01, 2015, 09:17 IGP1 = 3.8e-6 Torr. TGHT = 478A. TBHT reached max setpoint of 230A. Increasing ramping rate to 0.5A/min.  Monday, June 01, 2015, 13:15 Checked window for temperature readings, good visibility, no coating on window.  IGP1 = 9.1e-6 Torr. TGHT reached max setpoint of 580A 30min ago. Stepping up manually to a target temperature of 2000C...  Monday, June 01, 2015, 16:25 IGP1 = 6.5e-6 Torr. TGHT = 870A, 17.90V OMEGA = 1948C

 Monday, June 01, 2015, 17:59

After almost an hour at 870A, the temperature went up from 1948C to 1980C; however temperature around the target container/legs are >2000C.  The voltage on the power supply also went up slightly. 

There is a film coated on the window port and that could affect the temp reading.

To be safe, I lowered the TGHT to 830A/17.38V, temp at 1930C. 

Will keep at 830A for 4 hours and cool down this evening. 

Recommend: Using Ta-heat shields for sintering next time.

 Monday, June 01, 2015, 22:55

TGHT at 830A for almost 5 hours.  

TEMP has gone up to 1994C.  Voltage has also gone up to 19V.  

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

John Wong wrote:

Laura Lambert wrote:  Friday, May 29, 2015, 11:21 Total number of foils: 425 discs Total mass of materials [incl graphite foils]: 44.41g Total length packed: 12.3cm Container has no heat shields. No endcaps inserted to allow outgassing. Currently being pumped down.  Friday, May 29, 2015, 14:13 HS water valves opened, no leaks detected. IGP1 = 5.4e-6 Torr. Tapping up manually. Friday, May 29, 2015, 16:48 Tapped up manually to 20A. IGP1 = 5.9e-6 Torr. Initiating auto-ramp at 0.2A/min for the TGHT and 0.1A/min for the TBHT. Max setpoints set to 580A and 230A for the TGHT and TBHT respectively. Good Vacuum = 3.0e-5 Torr. Bad Vacuum = 4.0e-5 Torr.  Monday, June 01, 2015, 09:17 IGP1 = 3.8e-6 Torr. TGHT = 478A. TBHT reached max setpoint of 230A. Increasing ramping rate to 0.5A/min.  Monday, June 01, 2015, 13:15 Checked window for temperature readings, good visibility, no coating on window.  IGP1 = 9.1e-6 Torr. TGHT reached max setpoint of 580A 30min ago. Stepping up manually to a target temperature of 2000C...  Monday, June 01, 2015, 16:25 IGP1 = 6.5e-6 Torr. TGHT = 870A, 17.90V OMEGA = 1948C    Monday, June 01, 2015, 17:59 After almost an hour at 870A, the temperature went up from 1948C to 1980C; however temperature around the target container/legs are >2000C.  The voltage on the power supply also went up slightly.  There is a film coated on the window port and that could affect the temp reading. To be safe, I lowered the TGHT to 830A/17.38V, temp at 1930C.  Will keep at 830A for 4 hours and cool down this evening.  Recommend: Using Ta-heat shields for sintering next time.  Monday, June 01, 2015, 22:55 TGHT at 830A for almost 5 hours.   TEMP has gone up to 1994C.  Voltage has also gone up to 19V.   Cooling down at 2A/min for TGHT and 1A/min for TBHT.

 Tuesday, June 02, 2015, 12:37

Chamber was vented and the target was inspected. 

Some stressed marks on the target container can be observed.

The container is also slightly curved but otherwise it's fine. 

The materials packed length has expended outward so 3 discs were removed in order to insert the end caps. 

The packed length is now 16cm.

Two extra graphite foils were inserted on both ends, and previously coated/sintered TaC-end caps are inserted and expended. 

Rn foil is inserted & Std solutions are added. 

Ready for test-stand.

Link to photos for more details:

https://www.dropbox.com/sh/0cra7viqs9ro8q3/AADEGk8goGI4c-uzRQSGwWmxa?dl=0

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.