Angelina Chen wrote:

Thursday, July 25, 2024, 15:18 Target container consists of two np-Ta fibres disk samples. Both disks are made from heat stabilized np-Ta fibres (150 C for 17 hours) and were pressed at 8 tons / 300 MPa. Sample 1 was made from np-Ta fibres spun using Dope solution #1. The sample 1 disk has an average thickness of 0.727 mm and a diameter of 17.113 mm. The mass of the green sample 1 disk is 0.1957 g.  Sample 2 was made from np-Ta fibres spun using Dope solution #6. The sample 2 disk has an average thickness of 0.688 mm and a diameter of 17.123 mm. The mass of the heat stabilized fibres used to make the green sample 2 disk is 0.1860 g. The mass loss from pressing the heat stabilized fibres was virtually zero. Therefore, while the mass of the green sample 2 disk was not measured, it can be extrapolated to be 0.1860 g.  The target container was wrapped with Ta foil. Each sample disk was wrapped in graphite foil and placed inside the target container horizontally near the center.  The Omega slope was initially set to 0.980. After reviewing previous logbook on np-Ti The chamber is currently being pumped down. The current reading (as of 15:40) is 4.70e-05 Torr.  Two heating schedules will be tested. Heating schedule 1 entails heating both sample disks at ~1000 C until the pressure reaches below 1.00e-06 Torr. Once heating schedule 1 is completed, sample 1 will be removed. Heating schedule 2 entails heating sample 2 to ~1800 C until the pressure reaches below 1.00e-06 Torr. TGHT is estimated to be approximately 440A/7.6V to reach 1875 C (348A/5.8V to hold temperature at 1600 C). Refer to e-log ID#605.

 Friday, July 26, 2024, 09:52

Chamber has been pumped down overnight, pressure currently at 1e-6 Torr.

Initiate auto ramping 1A/min to reach 200 A. 

Good vac = 3 e-5 Torr

Bad vac = 5 e-5 Torr. 

Continue to monitor.

 Friday, July 26, 2024, 17:06

Gas evolution has seen observed to be completed as TGHT slowly ramping up.  Temp is currently reading at 1015 C, TGHT 164A/2.43V.  Pressure holding at 2.4e-6 Torr but slowly coming down, see attachment 1.  Will keep this setting and cool it down on Sunday.

 Sunday, July 28, 2024, 11:27

Temperature has been holding sturdy at ~1000C for over 36 hours, TGHT at 164A/2.59V (a slight increase in the voltage).  Pressure is currentlyat 4.5e-7 Torr (see attachment #2 for the archiver).

Ramping down TGHT at 1A/min. 

Will remove both samples on Monday to measure the mass loss.  Sample 1 will be analyzed.  Sample 2 will be loaded back to the Evap 2 for further heating to reach about 1800 C.

 Monday, July 29, 2024, 14:29

Both samples were removed from the chamber and measured for weight loss, and Sample 2 was put back for further heating; Thanks Darwin for helping up with this. 

Chamber is currently pump down, pressure at 6.0e-5 Torr. Will ramp up TGHT once the pressure has come down to 10e-6 Torr. 

 Monday, July 29, 2024, 16:52

Pressure at 6.5e-6 Torr.  Ramping up TGHT at 2A/min to reach 164A (previous setting at ~1000C).

 Tuesday, July 30, 2024, 09:02

Temperature has been holding at about 1000C. THGT at 160A(readback,, 164A setpoint)/2.56V.  Pressure 7e-7 Torr.

Stepping up 1A/min in 20A increment to reach 1800C. 

Continue to monitor.

 Tuesday, July 30, 2024, 10:07

Plotting out THGT (readback) vs Temp:

181 A/2.91V, 1070C

206A/3.34V, 1153C

225A/3.7V, 1213C

245A/4.1V, 1277C

Wednesday, July 31, 2024, 11:26

TGHT tripped off due to HS water flow NOT oK,  Attempted to clear it but did not work, see attachment #3. 

Will stop the process for now and investigate the problem. 

 Wednesday, July 31, 2024, 12:10

Darwin helped to check the surrounding of the lab for water leaks; everything was good and the chamber remained under vacuum. 

All the water paddle wheels were moving.  A slight touch of the HS paddle wheel somehow cleared the interlock. Maybe the connection was loose. 

We checked all the paddle wheels by shutting and opening the water valves.  All the interlocks responded correctly. 

Continue with the heating process...

Ramping up TGHT at 2A/min to reach 300A.

 Wednesday, July 31, 2024, 15:27

TGHT vs temp:

294A/5.1V 1477C

343A/6.0A, 1633C

402A/7.2V, 1818C

Will keep TGHT at 410A (setpoint) for night.(see attachment#4)

 Tuesday, August 06, 2024, 10:00

Venting Evap 2; the process is done.

The sample will be analyzed. 

Aaron Schmidt wrote:

Wednesday, August 07, 2024, 15:36: Roughing. Had initially been roughed & TP started w/ Marla CS, however it timed out. Restarting. Wednesday, August 07, 2024, 15:37: TP on. Wednesday, August 07, 2024, 15:46: Tripped at 4 KRPM. Restarted. Up to 5 KRPM. Failed to start. Thursday, August 08, 2024, 10:00: TP started.  Thursday, August 08, 2024, 10:12: TP Tripped but nearly spun up. Reset & Restarted. TP Green / on.

Thursday, August 08, 2024, 10:43

A cartridge was filled with graphite foils and loaded in an uncoated tantalum tube. The tube was wrapped with four Ta-sheets. A Ta-foil was placed in the tube's right end for measuring the temperature.

Good vacuum 3e-5 Torr

Bad vacuum 5e-5 Torr

Initial IGP1 = 5.06E-7 Torr

Starting ramp at 1A/min to 200 A

Friday, August 09, 2024, 09:40 Pressure started to rise, but temperature is not within pyrometer range yet. Current 42 A, Voltage 0.5 V

Friday, August 09, 2024, 10:46 Pressure started to reduce (peak 1.4e-5 Torr). Temperature is not within pyrometer range yet Current 100 A, Voltage 1.3 V

Friday, August 09, 2024, 11:28 Temperature started to be detected, but not stable enough. Current 135 A, Voltage 1.9 V

Friday, August 09, 2024, 12:54 Temperature 1129 °C, current 196 A, voltage 3 V.

Friday, August 09, 2024, 12:56

Next ramp 0.5A/min while taking temperature readings periodically until 250A

Friday, August 09, 2024, 14:45

IGP1 = 1.0e-6 Torr

Next ramp 1A/min to 480 A aiming at 2000 °C

Friday, August 09, 2024, 17:13

IGP1 = 1.9e-6 Torr, Current 327A, Voltage 5.3V

Ramp changed to 2A/min to 480 A aiming at 2000 °C

Coolded down after 4 hours at ~2000°C

at -2A/min

Friday, August 30, 2024, 11:31

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =3.1 e-07 Torr

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Heating autoramp starged at 1A/min on  TGHT  100A and TBHT

Then at 1A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

note: Left TBHT hole is off from center by a good margin

Sunday, September 01, 2024, 07:32

Starting initial ramp at 1A/min to 50A

Sunday, September 01, 2024, 15:20

have ramped ;up at 1A/min on both TGHT and TBHT but had two issues.

1) Set current and readback current have discrepancies but the TBHT discrepancy is significant (TBHT Set at 188 while RD is 231.9 A @ 1.9V)

   TGHT also has odd behavior with set point 405 giving 392A RD and 0.067V.  Will hold until 430pm before starting ramp down

Sunday, September 01, 2024, 16:30

Started rampdown at -2A/min TGHT and -1A/min TBHT

Note: OMEGA not able to give any reasonable readings

Tuesday, September 03, 2024, 13:51

After troubleshooting EVAP2 it was found that a copper line was touching the metal encasement grid most likely resulting in a short.  A short was seeing and it disappeared after moving the copper line away from the grid.  

Upon restarting on epics the PS went to maximum current and it was shut off after 30seconds to a minute.  The system was checked again by Arthur and TGHT was manually increased to 5A and then set to Zero again.  Arthur thinks that the PS probably requires this step after switching from local controls to remote.  Will start the sintering again as the container is coated but not sintered.

Tuesday, September 03, 2024, 14:03

ramping at 1A/min on both TGHT and TBHT to 90A. 

Tuesday, September 03, 2024, 22:25  

Started rampdown at -2A/min TGHT and -1A/min TBHT.  HIgh temperature from OMEGA was 1825 C at 430A readback on TGHT. 

Saturday, September 07, 2024, 09:54

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =8.1 e-07 Torr

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Heating ramp manually to 50A on TGHT and TBHT

Then at 1A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Saturday, September 07, 2024, 17:38

At 400 A set point on TGHT, read back is 392A and OMEGA reads 1840C.   TBHT set to 230A reads 233A.

It will be kept at this current for four hours before rampdown.

Monday, September 09, 2024, 19:06

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =2.6 e-06 Torr

Target temperature on OMEGA= 1800-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Heating autoramp starged at 1A/min on  TGHT   and TBHT until outgassin peak passed

Then at 1A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Monday, September 09, 2024, 19:08

Peak passed around 70A will continue ramp up at 1A/min to 400A on TGHT and 230A TBHT

Tuesday, September 10, 2024, 13:13

Was ramped down at -2 A/min TGHT and -1 A/min TBHT

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

Vacuum IGP1 initial =6.1 e-06 Torr

Target temperature on OMEGA= 1800-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final TGHT current= ~400A (adjustable)

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

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

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Tuesday, September 10, 2024, 22:22

1810C OMEGA at 439A TGHT readback

Wednesday, October 02, 2024, 19:21

Ta endcup at front end of container

End-caps on the graphite cartridge have holes for outgassing. 

initial heating @ 2A/min to 85 A then 2A/min to 120A TGHT.  Allow pressure to drop and then ramp to 400 A at 2A/min, leave 4 hours and start ramp down.

OMEGA slope = 0.99

Vacuum limits up to 400A: 5.0e-04 Torr -- 1.0e-02 Torr

Max current~400A (1900 C)

Wednesday, October 02, 2024, 19:25

Starting IGP1 = 6.65e-06 Torr

Thursday, October 03, 2024, 05:09

Starting rampdown.  Pressure stable at 4.5 e-06 Torr

Top temperature 1850 C on OMEGA

ramping down at -2A/min

Saturday, November 23, 2024, 11:08

 No milling ZrC material sintering inside graphite cartridge

baseline standard discs included for comparison. 

4 Ta foils wrapped around  container

one spring at the back end to retain the graphite cartridge

One Ta cap with perforations at the front for T readings

initial heating at 2A/min to 50A, followed by heating at 1A/min to 90 A

Initial IGP1= 1.0e-6 Torr

OMEGA slope =0.990

Good and bad vacuum =5.0e-5 Torr and 5e-4 torr

Saturday, November 23, 2024, 11:20

autoramp start at 2A/min to 50A on tght

Saturday, November 23, 2024, 20:11

allowed pressure to drop to 3.3e-6 Torr after degassing. 

Started ramp to 90A at 1A/min

Saturday, November 23, 2024, 23:46

started ramping at 1.5A/120s or 0.75A/min to 400A

Sunday, November 24, 2024, 07:55

Reached 1900 C at 410 A setpoint and 402 A on RD

Pressure did not increase after bumping up to 410 setpoint so will keep at this current until 11 am (four hours near 1900 C in total)

Sunday, November 24, 2024, 10:58

Final IGP1 at start of rampdown = 2.9e-6 Torr

Ramping down at -2A/min

Thursday, January 30, 2025, 09:17

Left to pump down on previous night

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =8.1 e-06 Torr

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~500A (adjustable)

Heating autoramp starged at 0.5A/min(1A/120s) to 60A on both TGHT and TBHT

Then at 0.5A/min  to 90 A, both TGHT and 230A TBHT

When pressure stable will ramp at 2A/min to ~500A on TGHT and 230A on TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Thursday, January 30, 2025, 09:20

currently ramping to 90A

Thursday, January 30, 2025, 12:30

Ramping to 120A @ 0.5 A/min

Thursday, January 30, 2025, 13:59

Ramping to 140 A at 1A/min (to check pressure change.  So far with slower heating, pressure has not spiked very high).

Thursday, January 30, 2025, 15:59

Started ramping @ 2A/30s to 500 A on TGHT

TBHT is at 230A

Thursday, January 30, 2025, 21:25

Target was sintered when OMEGA reading 1700-1750 C

At 640-660A on TGHT RD

Check target coating and repeat these setting if good.

Thursday, January 30, 2025, 21:43

Cooling started at -2A/min on TGHT and -1A/min TBHT

Saturday, February 01, 2025, 09:23

The coated container was wrapped in 4 Ta foil heatshield and left in evap2 over night to attain vacuum.

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~650A (adjustable)

Heating autoramp starged at 1A/min on  TGHT  and TBHT to 120A

Then at 2 A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Initial IGP1=5.6e-07Torr

Saturday, February 01, 2025, 11:05

@ 194A, 2.5V on TGHT, the pressure is dropping (has been dropping since 150A).  starting ramp at 4a/min

Thursday, February 13, 2025, 11:40

Log entries lost as computer rebooted.  Max temperature on OMEGA was 1850 C and held for 4 hours.  Cooled @ -2A/min TGHT and -1A/min TBHT.

Monday, March 03, 2025, 17:56

LP FEBIAD WO# 45447-21 initial wt=471.0 g (without T bar)

wrapped in 4 Ta heatshields.

Will heat at 2A/min to 95A on TGHT and TBHT

Then will heat at 2A/min to 1800 C ~400A on TGHT and 230A on TBHT

 Monday, March 03, 2025, 18:01

IGP1=3.3e-06 Torr

started initial ramp to 95A

Monday, March 03, 2025, 21:52

Start 4 hour count at 940 pm 

OMEGA reading 1750 C

TGHT= 435 A set and RD = 426 A, 7.0V

TGHT = 230A

Tuesday, March 04, 2025, 01:42

Start rampdown

Monday, March 10, 2025, 09:50

The coated container was wrapped in 4 Ta foil heatshield and left in evap2  over weekend to decrease pressure.

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~650A (adjustable)

Heating autoramp starged at 2A/min on  TGHT  and TBHT to 120A

Then at 2 A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Initial IGP1=

 Monday, March 10, 2025, 10:36

Initial IGP1= 8.5 e-06 torr

Starting ramp to 120A for both TGHT and TBHT

Monday, March 10, 2025, 16:57

RD TGHT =686A set to 700A, 10.8V

TBHT = 230A, 3.1V

OMEGA= 1710

Will leave for 4 hours

 Monday, March 10, 2025, 20:42

IGP1=7.9e-06 Torr

OMEGA= 1750 C

TGHT = 686 A, 10.8V

TBHT= 230A, 3.1 V

starting rampdown at -2A/min TGHT and -1A/min TBHT

Tuesday, March 11, 2025, 15:44

The coated container was wrapped in 3 Ta foil heatshields.

16 caps and 4 springs

Target temperature on OMEGA= 1750-1800C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= N/A

Final TGHT current= ~400A (adjustable)

Wednesday, March 12, 2025, 07:07

Heating autoramp started at 1A/min on  TGHT 90A

Then at 4A/min  to 400 A.

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

 IGP1 initial =4.8e-07 Torr

Wednesday, March 12, 2025, 09:52

starting ramp at 2A/min to 400A 

Wednesday, March 12, 2025, 10:21

increasing ramp to 4A/min (2A/30s)

Wednesday, March 12, 2025, 11:57

TGHT=441A, 7.2V

Will keep for 4 hours

1750C

Wednesday, March 12, 2025, 15:57

starting rampdown at -2A/min

Tuesday, March 18, 2025, 06:48

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =9.1 e-07 Torr

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Heating autoramp starged a 2A/min on  TGHT   and TBHT

 to =300 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Tuesday, March 18, 2025, 13:47

OMEGA read 1850C at 380A on TGHT.  The temperature dropped and current was raised to 390A, 6.5V on TGHT.

TBHT was kept at 230A, 3.2V

Temperature dropped to 1756 after 4 hours of sintering.  Will start rampdown at -2A/min for TGHT and -1A/min TBHT. 

Wednesday, March 19, 2025, 13:08

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =

Target temperature on OMEGA= 1800-1850 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Thursday, March 20, 2025, 06:10 

IGP1 initial = 6.1e-7 Torr

 start ramp at 2A/min

Thursday, March 20, 2025, 07:04

paused ramp to prevent pressure spike

Thursday, March 20, 2025, 10:16

OMEGA 1800 C @ TGHT = 402A, 6.8V

Will leave for 4 hours.

Thursday, March 20, 2025, 13:53

Starting rampdown at 2A/min TGHT and 1A/min TBHT

Tuesday, March 25, 2025, 15:25

The coated container as wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =e-07 Torr

Target temperature on OMEGA= 1800-1850 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Will be left overnight to pump down

Wednesday, March 26, 2025, 09:07

starting ramp up at 2A/min to 230A for both TGHT and TBHT

Wednesday, March 26, 2025, 12:48

1800 C at 400A TGHT, 6.9V TGHT

Leaving for 4 hours

Friday, March 28, 2025, 06:49

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =8.0e-07 Torr

Target temperature on OMEGA= 1800-1850 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

Starting ramp at 2A/min

Friday, March 28, 2025, 09:41

At 412A readback on TGHT OMEGA reads 1702 C.  Maybe re-use of Ta heatshields resulted in loss of efficiency.  Will ramp to 420 A and leave for 4 hours.

Friday, March 28, 2025, 14:25

Started rampdown at -2A/min TGHT and -1A/min TBHT

Friday, April 04, 2025, 06:41

Total number of foils:328

Total length packed 15.2 cm

container has 4 Ta heat shields (one inner only around fins)

No endcaps inserted to facilitate out-gassing

Ta coated spring at back, coated cap at front with perforations

ramp to 500A @ 1A/min TGHT and to 230A on TBHT

max approx 700A on TGHT and 230A on TBHT (Omega slope set = 0.990)

Then temperature = 1800C

TBHT will be set fixed at 230 A (max).  TBHT heated manually and automatically to max.

Good vac at 5.00 e -4 Torr

Bad vac at 5.00 e-2 Torr

 IGP1= 1e-06 Torr at start of initial ramp.

initiating ramp up

 Friday, April 04, 2025, 10:54

Paused ramp at 128.5A TGHT and 130.2 A TBHT.  Will hold and let pressure drop.

IGP1 = 5.43e-04 Torr currently

Friday, April 04, 2025, 14:04

restarting ramp

IGP1=2.6e-05 Torr

Friday, April 04, 2025, 16:35

increasing ramp to 3A/min

@18:15 ramp was slowed down to 2A/min and left to reach 730~A

Friday, April 04, 2025, 22:54

Current was stopped at 733A on readback and left for 3.5 hours, then manually ramped to 738A for 0.5 hours. 

This is in accordance with the initial oven (Elog 619)

Friday, April 04, 2025, 23:45

starting ramp down at -1A/min TBHT and -2A/min TGHT

Friday, April 11, 2025, 06:18

 initial IPG1=2.3 e=06 Torr

Ta container tube, wrapped in 4 Ta foil heat-shields, and loaded with _________ D shaped discs in a 12mm graphite cartridge with usable 11mm

conditioning tube WO = 41882-4

End-caps on the graphite cartridge have holes for outgassing.  One spring each end in the Ta container

initial heating @ 2A/min to 85 A then 2A/min to 120A TGHT

OMEGA slope = 0.99

Vacuum limits up to 400A: 5.0e-04 Torr -- 1.0e-02 Torr

Friday, April 11, 2025, 14:45

reached 1800 C on OMEGA at 398A readback

Will take to ~410 A and leave for 4 hours

Friday, April 11, 2025, 18:55

at 415A OMEGA was 1879 C

was left for 4 hours at this setting

starting rampdown at -2A/min

Evaporator #2 is still under construction.  For further information please contact Jens Lassen.