Nikita Bernier wrote:

Nikita Bernier wrote:  Monday, September 24, 2012, 15:01 The target boat with TaC coating is being used again. The inside of the boat is covered with a 0.002 inches thick Ta foil with TaC coating, wrapped with a 0.002 inches thick Ta foil. Chamber was pumped down to 6e-6 Torr before the Heat Shield cooling water valve was opened. A small vacuum bump was detected (See attachment #1). It is not clear if it was caused by a water leak or not. After consulting with Peter, I will wait for the vacuum to be below e-07 Torr before turning the target heater on.        Monday, September 24, 2012, 18:02 The vacuum was stable until 1e-06 Torr. The target heater was turned on and tapped up to 60 A (0.8 V).  Evaporator #2 is now auto-ramping overnight at 0.2 A/min, up to 800-850 A, with the maximum voltage limited at 14 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum).     Tuesday, September 25, 2012, 15:11 Sintering process is going smoothly. See Attachment 1. The auto-ramping was increased to 1 A/min up to 800-850 A.     Tuesday, September 25, 2012, 16:11  And the voltage limit was increased to 18 V ! See Attachment 2.    Tuesday, September 25, 2012, 19:13 Around 806 A (readback), voltage increased more quickly than the current. It seems like resistance is building up. After reaching 836 A (readback), the current was tapped down to 800 A (readback)/ 816 A (setting) in an effort to save the Ta boat. See Attachment 3. The current will stay at 800 A for ~4 hours before ramping down.

 Wednesday, September 26, 2012, 14:31

The current was tapped down twice as resistance was building up. After 4 hours at ~800 A, the TGHT was ramped down at 2 A/min. See Attachment 1. The target boat was cooled down for 4 hours before the chiller was turned off.

Also I had trouble measuring the temperature. I was unable to get a clear picture with the pyrometer. Therefore the exact temperature remains unknown, but from previous experiments, 800 A was about 1400°C.

The TaC coated Ta foil is very brittle. There is a lot of crystallisation on the Ta boat. See attachment 2. It is unlikely that the boat would survive many more sintering. Therefore it will be used for BeO pellets tests. 

When John gets back, I suggest we use a new boat coated with TaC, without additional layers. (See message #15 when this target boat was sintered up to 900A (local 893A/16.88V), Measured temp @ 1500°C)

The purpose of this experiment is to improve the TaC coating mixed with other metals as additives.  The coating solution will be sprayed on Ta metal (0.015" thick, same thickness as the target container).

The samples will be sintered at ~ 1800C.  Once the process is completed, a graphite tube will be inserted into the tube, and then re-heated it up to 1800C. 

This test will show how good the protective layer to prevent the graphite to react with the Ta metal.

Wednesday, November 06, 2013, 17:11

Step #1

Two samples: 

1.  A short tube (same diameter as the usual container)

2.  A cross section of the tube.

Both samples are coated with the TaC matrix spray: 

0.05 moles TaC

0.005 moles of Mo2C, VC, Cr3C2, NbC 

A Rh foil is used as a protective under layer.

see links for pictures:  https://www.dropbox.com/sh/866zsp44nnjeg2z/LqCThu-G_0

The target boat is wrapped with 3 layers of heat shields. 

Samples will be heated up to 600A ~1800C

Chamber is currently being pumped down.

 Friday, November 08, 2013, 17:13

Chamber was pumped down to ~2e-6 Torr.  HS water valve is opened and no leaks were detected. 

TGHT will be ramped up to 580A at 1A/min. 

Monday, November 11, 2013, 08:10  

TGHT has reached to 580A; samples has been heated at that current for over the weekend. 

IGP2 currently at 3.5e-7 Torr.

Auto cooling initiated, ramping rate at -2.0A/min.

 Step 2:

The coated tube is sintered with TaC-matrix.

The graphite tube is inserted in the tube and will be heated back up; see link for details:

https://www.dropbox.com/sh/ji0rhlj0v1tfj1w/cRv1I3VJXE

Chamber is currently pumped down to 1.8e-6 Torr.

TGHT will first be ramped up to 450A (1A/min) to see how the reaction behaves, then a caution ramp up to 600A will take place. 

 Friday, November 15, 2013, 11:04

TGHT reached to 450A.  Cooling down to 0A.  Chamber will be vented for inspection.

 Monday, November 18, 2013, 17:22

Continue Step#2:

The sample looks ok after heating at 450A.

Re-heating it to 500A. 

Chamber has been pumped down to 4.0e-6 Torr. 

Initiated auto-ramping...

 Thursday, October 25, 2018, 10:36

Container is coated with TaC and wrapped with Ta heat-shield (3 layers)

Desired temp = 1900 C (expected TGHT ~445A/7.5V), TBHT will be set fixed at 230A (max).

Chamber is currently being pumped down

 Friday, October 26, 2018, 08:40

Pressure at IGP1 1.06e-6 Torr. 

Tapped up TGHT and TBHT manually to 40 A

Waited 1 hr for vacuum to stabilize.

IGP1 = 8.9e-6 Torr

Good vac at 3.00-5 Torr

Bad vac at 5.0e-5 Torr.

Initiating auto ramp for TGHT @ 1 A/min to a max setpoint of 350 A

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

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

 Friday, October 26, 2018, 10:46

At 62 A, the vacuum overpassed the "Bad vacuum " limit and the current reduced to 54 A.

when the pressure returned to the "Good vac" limit the ramping started automatically.

Friday, October 26, 2018, 16:59

TGHT= 450 A, Temperature = 1878 C

Ramping rate increased to 1A/min for the TBHT.

Tapped manually to 454 A, Temperature 1880 C.

Saturday, October 27 2018, 10:00 

Ramping down to 0 A @ 2 A/min.

Monday, October 29, 2018, 12:39

 Venting EVAP2, TaC coat sintering completed.

 Wednesday, October 31, 2018, 19:35

Container is coated with TaC and wrapped with Ta heat-shield (3 layers)

Desired temp = 1900 C (expected TGHT ~445A/7.5V), TBHT will be set fixed at 230A (max).

Chamber is currently being pumped down

 Thursday, November 01, 2018, 10:31

Pressure at IGP1 9.44e-7 Torr. 

Tapped up TGHT and TBHT manually to 40 A

Thursday, November 01, 2018, 12:32

Waited ~1 hr for vacuum to stabilize.

IGP1 = 1.42e-6 Torr

Good vac at 3.00-5 Torr

Bad vac at 5.0e-5 Torr.

Initiating auto ramp for TGHT @ 1 A/min to a max setpoint of 350 A

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

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

 Tapped manually to 445 A, Temperature 1896 C.

Friday, November 02, 2018, 07:35

TGHT 7.86 V 445.6 A

TBHT 3.22 V 233.3 A

IGP1 1e-6 Torr

Ramping down TGHT and TBHT to 0 A @ 2 A/min.  

Friday, November 02, 2018, 17:28

Monday, October 29, 2018, 12:39

Venting EVAP2, TaC coat sintering completed. 

 Tuesday, January 15, 2018, 17:30

Tantalum tube was coated with TaC and wrapped with Ta heat-shield (3 layers)

Desired temp = 1900 C (expected TGHT ~445A/7.5V), TBHT will be set fixed at 230A (max).

EVAP2 currently pumping down.

 Pressure at IGP1 4.71 -7 Torr. 

Tapped up TGHT manually to 40 A

Waited ~1 hr for vacuum to stabilize.

IGP1 = 9.96-7 Torr

Good vac at 3.00e-5 Torr

Bad vac at 5.00e-5 Torr.

Initiating auto ramp for TGHT @ 1 A/min to a max set point of 350 A

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

 Thursday, January 17, 2019, 15:31

The tube remained at ~1900 C for 6 hours.

IGP1=5.8e-7 Torr

TGHT = 427 A, 7.23 V

Min Temperature = 1890 C

Thursday, January 17, 2019, 15:33

 Auto-ramp set to TGHT 0 A @ -2 A/min. 

 Wednesday, April 03, 2019, 16:57

Tantalum tube was coated with TaC and wrapped with Ta heat-shield (3 layers)

Desired temp = 1900 C (expected TGHT ~445A/7.5V).

EVAP2 currently pumping down.

 Thursday, April 04, 2019, 05:12

IGP1 = 4.5e-7 Torr

The current is tapped manually to 40 A

After1 hour IGP1 = 1.18e-6 Torr, the autoramp was set to 1 A/min to 400 A

Thursday, April 04, 2019, 18:58

After 4 hours at ~1900 C:

IGP1 = 6.13e-7 Torr 

TGHT = 6.74 V, 416.06 A

Thursday, October 03, 2019, 08:58

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Initial weight including heat-shields = 427 g

Desired temperature = 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 was pumped down previous night.

IGP1= 7.81e-07 Torr

Manually tapping up to ~40A on both TGHT and TBHT at ~1A/min

Good vacuum = 3.00 e-5 Torr

Bad vacuum = 5.00 e-5 Torr

Thursday, October 03, 2019, 09:21

Manually tapped to 50A on TGHT and TBHT

Will allow pressure to stabilize and begin autoramp TGHT and TBHT at 1A/min to 400A and 230A respectively.

autoramp increments might be increased to 2A/min depending on stability of system.

Thursday, October 03, 2019, 10:00

TGHT = 51.6A, 0.36V

TBHT = 49.5A, 0.62V

IGP1=9.6e-7 Torr

Starting autoramp at 1A/min to a max of 400A for TGHT and 230A for TBHT.  Will monitor and increase ramp increments to 2A/min if stable.

Thursday, October 03, 2019, 11:09

TGHT = 103A, TBHT=97A

IGP1=9.1e-06 Torr and dropping

Will increase autoramp increments to 2A/min

Thursday, October 03, 2019, 11:41

With TGHT = 148A, 1.9V and TBHT = 141A, 2.3V

IGP1= 7.9e-6 Torr

Autoramp was increased to 3A/min

Thursday, October 03, 2019, 13:45

TGHT=401A, 6.9V

TBHT=233A, 4.2V

IGP1= 1.14e-05Torr

OMEGA = 1874

begin manual ramp to 1900C

(Temperature dropping as pressure drops)

 Thursday, October 03, 2019, 14:11

 TGHT= 416A, 7.1V

TBHT=233A, 4.2V

OMEGA = 1900 C

IGP1= 6.9e-06 Torr and trending down

Thursday, October 03, 2019, 15:24

TGHT manually bumped to 421A,  7.2 V because temperature dropped slightly.

Thursday, October 03, 2019, 19:00

TGHT manually increased to 425A, 7.3V

Thursday, October 03, 2019, 19:12

TGHT = 424.9A, 7.3V

TBHT=233.2A, 4.1V

OMEGA= 1897 C

IGPA=1.45e-06 Torr

Starting ramp-down at -1A/min on TGHT and 0.5A/min on TBHT

Friday, October 04, 2019, 11:34

Container taken out.

Friday, October 04, 2019, 11:37

Each endcap is separated with a disc of graphite foil and rolled into packs of 5 within a foil envelope in a target boat.

There are also 3 coated springs, one in between endcaps and two on either end

The boat is wrapped with 2-layers of Ta heatshields.

Chamber pumping down

OMEGA slope = 0.99

Will Tap TGHT up manually to 40 A then autoramp to 400A at 1A/min.

Final desired temperature on OMEGA (tap)= 1800C

Monday, October 07, 2019, 09:08

Sunday night heating started at 1A/ min on TGHT to 54 A

heating paused for 1 hour to allow IGP1 to equillibrate.  Then restarted at 1A/min to 400A as planned. 

This morning IGP1 = 1.3e-06 Torr

TGHT = 401A, 4.2V

OMEGA = 1550 C

Monday, October 07, 2019, 09:36

manually tapping to 1800 C

Monday, October 07, 2019, 14:09

Temperature @ ~1800 for 3.5 hours

TGHT= 495.4, 9.2 V

IGP1= 1.1e-06 Torr Pressure Steady there begin cooling

Cooling @ -2A/min

Thursday, October 17, 2019, 12:00

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Desired temperature= 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 was pumped down on the previous night.

Good vacuum= 3.00 e-5 Torr

Bad vacuum = 5.00 e-5 Torr

Ramped TGHT and TBHT to 40A at 0.5A/min

Initial IGP1= 7.0 e-07 Torr

Thursday, October 17, 2019, 13:53

After pressure stabilization at 40A:

 Autoramp TGHT and TBHT at 1A/min to 400A and 230A respectively.

 Friday, October 18, 2019, 6:20

TGHT = 400A, 6.52V, TBHT= 233A, 4.1V

OMEGA = 1733C

Start autoramp to 430A on TGHT at 1A/min

Friday, October 18, 2019, 7:05

TGHT= 431A, 7.1V

TBHT= 233A, 4.1V

IGP1= 1.13e-06 Torr

OMEGA = 1828 C

Set autoramp to 465 at 1A/min

Friday, October 18, 2019, 11:13

TGHT = 465A, 7.8V, TBHT = 233A, 4.1V

OMEGA = 1865C

(Something is different with the heat dissipation on this target.  Will leave at this current and start cooling at 1200 noon to avoid container strain)

 Friday, October 18, 2019, 12:00

TGHT = 462.7A, 7.8V

TBHT= 233.4A, 4.1V

OMEGA = 1863C

IPG1= 1.02e-06 Torr

Commence cooling at -2A/min for TGHT and -1A/min for TBHT

 Monday, October 21, 2019, 09:11

Pump down and dismount.

 Friday, November 22, 2019, 18:18:

Friday, November 22, 2019, 18:18: Roughing

Friday, November 22, 2019, 18:23: Turbo on .

Friday, November 22, 2019, 18:32: Turbo at speed 

12.3

Saturday, November 23, 2019, 14:00

Container coated with TaC and wrapped with 3 Ta heat shields.

Desired temperature= 1900 C, Omega Slope set = 0.990, Auto TGHT at 0.2A/min to reach 400A, TGHT will be tapped up accordingly to reach desired Temp.

TBHT will be set fixed at 230 A (max). 

Good vac at 3.00e -5 Torr

Bad vac at 5.00e-5 Torr

Chamber pump down was started on Friday November 22; however.

No leaks were observed when turning water lines on.

IGP1= 4.6e-07 Torr

 Saturday, November 23, 2019, 15:30

autoramp at 0.5A /min up to 50A for both TGHT and TBHT and maintained for 1 hour.

Saturday, November 23, 2019, 16:15

IGP1= 1.1e-06 Torr

Auto Ramp to 450 A on THGT and 230A on TBHT at 0.5A/min

Saturday, November 23, 2019, 23:44

IGP1= 5.2e-06 Torr

TGHT = 248A, 2.9V  TBHT= 233A 2.9V

Increased ramp step to 1A/min to 620 A

Sunday, November 24, 2019, 00:14

IGP1=1.9e-06 Torr

TGHT = 274.3, 3.3V   TBHT= 233A, 2.9V

Sunday, November 24, 2019, 07:33

IGP1=3.2e-06 Torr

OMEGA= 1490C

TGHT = 619 A, 9.1V   TBHT=233A, 2.9V

Continue ramping THGT at 1A/min to 700 A

Sunday, November 24, 2019, 10:05

IGP1= 2.1 e-05 Torr

OMEGA= 1676 C

TGHT= 700A, 10.6V   TBHT= 233A, 2.0V

Start autoramp to 780A as per regression in attachment

Sunday, November 24, 2019, 13:22

Autoramp to 795A  for TGHT

Sunday, November 24, 2019, 21:16

OMEGA= 1854 C

TGHT= 789.6A, 12.27V  TBHT= 233.A, 2.9V

IGP1= 2.0e-05

Will allow pressure to stabilize lower.

Sunday, November 24, 2019, 22:16

TGHTT= 789.6A, 12.3V TBHT=233.3A, 2.9V

OMEGA=1855C

IGP1 = 6.9e-06Torr

Start cooling TGHT at 2A/min and TBHT at 1A/min

 Wednesday, March 18, 2020, 07:10

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Desired temperature= 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 was pumped down on the previous night.

Good vacuum= 3.00 e-5 Torr

Bad vacuum = 5.00 e-5 Torr

Ramped TGHT and TBHT to 40A at 0.5A/min

Initial pressure IGP1 = 4.8e-7Torr

 Wednesday, March 18, 2020, 09:29

After an hour pressure reduced to 5.45e-6 Torr

TGHT; 0.518 V, 40.5 A

TBHT: 0.41 V, 38.6 A

Autoramp TGHT and TBHT at 1A/min to 400A and 230A respectively.

 Wednesday, March 18, 2020, 18:29

TGHT = 400A, 6.6V, TBHT= 232.9, 3.9V

OMEGA = 1240 C, this is 500 degC lower than previous LP-SIS at same conditions

https://elog.triumf.ca/TIS/Evaporator_2/464

Start autoramp to 460A on TGHT at 1A/min

Wednesday, March 18, 2020, 20:51

TGHT: 464 A, 7.75 V

Temperature 1328, I won't increase the temperature because there is a chance that the reading is 500 degC off and the target is sitting at 1828 degC instead of 1328 degC 

Wednesday, March 18, 2020, 23:17

After ~4 hours at 1317 degC according to the pyrometer:

TGHT = 7.7 V, 457.8 A,

TBHT = 3.9 V, 232.9 A,

IGP1 = 1.16e-6

Commence cooling at -2A/min for TGHT and -1A/min for TBHT

Thursday, March 19, 2020, 15:53

Venting and dismounting.

The coating does not have the quality to be used online, another LP-SIS will be coated and sinter

 Tuesday, August 18, 2020, 09:06

A short tantalum tube was coated with TaC and wrapped with 3 layers of Ta,

a Ta foil was attached to the end of the tube to be able to measure the temperature during heating

Desired temperature= 1900 C,

Omega Slope set = 0.990,

IGP1 = 3.75e-7 Torr

Autoramp set to TGHT at 0.2 A/min to reach 52 A

Tuesday, August 18, 2020, 13:47

IGP1=  6.8e-7 Torr

TGHT =0 .511 V, 51.3 A

IGP1 = 6.8e-7 Torr

Autoramp set to TGHT at 0.5 A/min to reach 100 A

IGP1 = 3.3e-7 Torr

Autoramp set to TGHT at 0.5 A/min to reach 430 A 

Wednesday, August 19, 2020, 06:57 

Autoramp stopped at 402 A

IGP1 = 1.12e-6 Torr

TGHT = 5.6 V, 403.65 A

Autoramp set to TGHT at 1 A/min to reach 500 A 

Wednesday, August 19, 2020, 08:59

IGp1 = 1.7e-6 Torr

 TGHT = 7.22 V, 500.34 A

After 30 min at 1900 °C, autoramp set to TGHT at -1 A/min to reach 450 A, the ramp will be stopped when the temperature reads 1850 °C

Autoramp stopped at 1845 °C

IGP1 = 1.17e-6 Torr

TGHT = 6.8 V, 472.95 A 

Thursday, August 19, 2020, 17:28

 A short tantalum tube was coated with TaC and wrapped with 3 layers of Ta,

a Ta foil was attached to the end of the tube to be able to measure the temperature during heating

Desired temperature= 1900 C,

Omega Slope set = 0.990,

Thursday, August 20, 2020, 17:29

IGP1 = 4.25 e-7 Torr

Autoramp set to 0.5A/min to 400 A 

 Thursday, August 20, 2020, 20:36

IGP1 = 6.78e-7 Torr

TGHT = 267.7 A, 3.28 V

Autoramp set to 0.4 A/min to 450 A

Friday, August 21, 2020, 10:28

 IGP1=7.23e-7 torr

TGHT = 6.3 v, 446.3 A

Omega = 1603 °C

Autoramp set to -5 A/min

Tuesday, March 02, 2021, 11:26 

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Initial weight including heat-shields = 433.8 g

Desired temperature = 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 will be pumped down over night.

Good vacuum = 3.00 e-5 Torr

Bad vacuum = 5.00 e-5 Torr

Wednesday, March 03, 2021, 13:28

IGP1 = 4.0 e-7 Torr

Start ramping @ 1A/min to 20A on both TGHT and TBHT

Wednesday, March 03, 2021, 15:03

Start ramping @1/min to 60A on Both TGHT and TBHT

Wednesday, March 03, 2021, 22:42

TGHT = 60A, TBHT = 60A

IGP1= 4.2 e-7 stable

Start ramping to 400A @ .5A/min for TGHT and @0.5A/min for TBHT to 230A

Thursday, March 04, 2021, 11:56

TGHT = 400 A, TBHT =230A

IGP1= 1.9e-6 Torr

OMEGA = 1695 C

Continue ramp up @0.5A/min to 430A on TGHT

Thursday, March 04, 2021, 14:02

IGP1 = 1.87e-6 Torr

TGHT = 434 A , 7.2 V

OMEGA = 1787 C

Will tap up manually 450A @ on TGHT and leave at that current for ~4 hours

Thursday, March 04, 2021, 19:35

After ~ 5 hours at 1829 C max OMEGA reading

OMEGA = 815 C 

Start ramp down at 1A/min on TGHT and 0.8A/min for TBHT

IGP1= 1.2e-6 Torr

 Friday, March 05, 2021, 10:47

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Initial weight including heat-shields = 431.0 g

Desired temperature = 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 will be pumped down over night.

Good vacuum = 3.00 e-5 Torr

Bad vacuum = 5.00 e-5 Torr

 Saturday, March 06, 2021, 10:29

IGP1= 2.7 e-07 Torr and stable

AutoRamp at 1A/min to 40 A on TGHT and TBHT

Saturday, March 06, 2021, 22:36

IGP1= 2.2e-07 Torr

TGHT = 40.3 A, .46V

TBHT = 38.48 A, .48 V  (set to 40 A)

Start Autoramp at 0.5A/min to 400 A on TGHT and 230A on TBHT

Sunday, March 07, 2021, 07:48

IGP1=8.5e-7 Torr

TGHT = 287 A, 4.6V

TBHT = 232 A, 4.0 V

OMEGA = 1493C

 Increase ramp speed on TGHT to 2A/min to 400A

Sunday, March 07, 2021, 08:36 

 IGP1=1.7 e-06 Torr

TGHT = 373.7 A, 6.3V

TBHT = 232.9 A, 4.1 V

OMEGA = 1752 C

Sunday, March 07, 2021, 08:53

 IGP1= 1.7e-06 Torr

TGHT = 400 A, 6.8 V

TBHT = 232.8 A, 4.1 V

OMEGA= 1842

Ramp TGHT @ 2A/min to 420 A as per attached current approximation

Sunday, March 07, 2021, 09:25

OMEGA=1915 C

TGHT = 420A, 7.2V

TBHT= 232.8 A, 4.1V

IGP1= 1.6 e-06 Torr

Tap down manually to approx 1900 C

TGHT = 412.9 A, 7.0 V and OMEGA=1900 C

Will leave for about 4 hours at this temperature

Sunday, March 07, 2021, 13:05

IGP1= 1.1 e-06 Torr

TGHT = 415 A, 7.2 V

TBHT = 232.8 A, 4.1 V

OMEGA = 1880C

Start cool down at -2A/min on TGHT and -1A/min TBHT

Tuesday, March 09, 2021, 11:54 

 Container coated with TaC and wrapped with 3 Ta heat shields.

Desired temperature= 1900 C, Omega Slope set = 0.990, Auto TGHT at 0.2A/min to reach 400A, TGHT will be increased  accordingly to reach desired Temp.

TBHT will be set fixed at 230 A max).

Good vac at 3.00e -5 Torr

Bad vac at 5.00e-5 Torr

Chamber pump down

Wednesday, March 10, 2021, 08:32

IGP1 = 2.6 e -07 Torr

Start autoramp @ 1A/min to 40 A on both TGHT and TBHT

***Autoramp aborted due to work on EF12 affecting EVAP2***

Will have to resume Thursday or Friday

Saturday, March 13, 2021, 7:54

  IGP1= 3.8e-07 Torr

Initiate heating @ 0.5A/min TBHT and TGHT to 60 A

Saturday, March 13, 2021, 23:01

IGP1 = 2.7e-07Torr

TGHT = 60.5A, 0.7V

TBHT= 60.0A, 0.7V

Initiate ramp @ 1 a/min to 400 A on TGHT and 230A on TBHT

Sunday, March 14, 2021, 08:45

IGP1= 8.2e-07 Torr

TGHT = 400A, 5.6V

TBHT = 232.9A, 3.0V 

OMEGA = 1142 C

Continue ramping to 460 A on TGHT at 1a/min

 Sunday, March 14, 2021, 10:11

IGP1 = 1.0 e-06 Torr

TGHT= 460.4 A, 6.5 V

TBHT = 232.9 A, 3.0 V

OMEGA = 1239 C

Will ramp up to 500 A at 1a/min on TGHT

Sunday, March 14, 2021, 10:53

 IGP1 = 1.3 e-06 Torr

TGHT= 495 A, 7.2 V

TBHT = 232.9 A, 3.0 V

OMEGA = 1316 C

Will ramp up to 600 A at 1a/min on TGHT

Sunday, March 14, 2021, 12:45

IGP1 = 3.0 e-06 Torr

TGHT= 604 A, 9.1 V

TBHT = 232.9 A, 3.1 V

OMEGA = 1610 C

Will ramp up to 660 A at 1a/min on TGHT 

Sunday, March 14, 2021, 17:01

IGP1= 2.4e-06 Torr

TGHT =  664 A, 10V

TBHT = 232.9 A, 3.1V

OMEGA = 1733 C

tapping TGHT to 740 A

OMEGA = 1883 C

 Sunday, March 14, 2021, 21:45

IGP1= 3.1e-06 Torr

TGHT =  744A, 11.5V

TBHT = 232.9 A, 3.2V

OMEGA = 1875 C

Start cooling TGHT @-3A/min and TBHT @-1A/min

 Tuesday, March 16, 2021, 08:28 

Each endcap is separated with a disc of graphite foil and rolled into packs of 5 within a foil envelope in a target boat.

There are also 4 coated springs, one in between endcaps and three on the ends

The boat is wrapped with 3-layers of Ta heatshields.

Chamber pumping down

OMEGA slope = 0.99

Will ramp TGHT up to 40 A then autoramp to 400A at 1A/min.

Final desired temperature on OMEGA (tap)= 1800C

Tuesday, March 16, 2021, 11:22

 IGP1= 3.5e-06 Torr

TGHT = 40A, 0.4V

Will ramp up at 1A/min to 400 A

Wednesday, March 17, 2021, 08:06

IGP1=  2.98 e-07 Torr

TGHT = 400 A, 4.3V

OMEGA shows no temperature reading.  Will ramp up to 450A at 1A/min

Wednesday, March 17, 2021, 08:58

OMEGA still shows no reading

IGP1= 4.2e-07 Torr

ramping to 470A @ 1A/min 

Wednesday, March 17, 2021, 09:21

OMEGA no reading

IGP1 = 4.4 e-07 Torr

TGHT = 470 A, 5V

ramp up to 490 A at 1A/min

Wednesday, March 17, 2021, 11:05 

TGHT at 490 A, 5.2 V since 10 am.  Will start cooling at 2 pm.  

Wednesday, March 17, 2021, 13:47

TGHT = 493A, 5.3V

IGP1= 3.2e-07 Torr and stable

Start ramp down at -2A/min

Thursday, March 18, 2021, 11:20 

The boat was dismounted but the materials had not sintered properly.  The boat looked very twisted.  Everything was transferred to a new boat with uncoated Ta caps at either end.  

It was left overnight to establish vacuum.

Friday, March 19, 2021, 08:23

IGP1= 2.2 e-07 Torr

initiate heating at 1A/min on TGHT to 60 A

Friday, March 19, 2021, 10:04

IGP1= 3.6 e-07 Torr

TGHT = 60 A, .73 V

Ramp up to 450 A @ 2A/min

Friday, March 19, 2021, 14:26

OMEGA 1895 at 455A, 8.4 V

manually ramp down to 1800C

OMEGA 1800C at 416A, 7.6V

will leave like that for 3 hours more

Friday, March 19, 2021, 17:12

OMEGA 1795 C

 TGHT = 415A, 7.6V

IGP1= 6.8e-07 Torr

Start ramp down at -2A/min

Monday, March 22, 2021, 23:07 

Marla removed from Evap 2.  Sintering vwas very good.  The container with Ta caps is better for sintering these pieces.

 Thursday, September 02, 2021, 06:36

Ta tube was coated with TaC and wrapped with Ta heat-shields (3 layers)

Desired temperature = 1900 C (expected TGHT ~430 A), TBHT will be set fixed at 230A (max).

Evap 2 was pumped down over previous night

Good vacuum = 3.00 e-5 Torr

Bad vacuum = 5.00 e-4 Torr

IGP1=7.7e-07 Torr

Initiate autoramp to 50 A @ 1A/min

Thursday, September 02, 2021, 06:54 

Stopped autoramp after reading email about EF-12 trip and compressed air issue.  Reset to 0 A both TGHT and TBHT

Thursday, September 02, 2021, 12:01

Ispite of site compressed air issues, EVAP 2 has not tripped.  Will manually increase current to40A for both TGHT and TBHT.

IGP1= 1.06 E-06 Torr. 

Friday, September 03, 2021, 08:06

 IGP1= 7.2e-07 Torr

TGHT= 43A, 0.5 V

TBHT= 41A, 0.48 V

Start autoramp at 1A/min to 90A on both TGHT and TBHT

Friday, September 03, 2021, 10:22

IGP1= 1.55 e-06 Torr

TGHT = 90.1 A, 1.1 V

TBHT= 90.0 A, 1.2 V

Continue ramp up at 1A/min to 400 A for TGHT and 230A for TBHT 

Friday, September 03, 2021, 16:05

430A on TGHT will keep for four hours.  OMEGA = 1856 C but according to regression should be 1900.  will keep at this temp. 

Friday, September 03, 2021, 21:11

OMEGA has been at 1875C for 4 hours.  Will start ramp down @ -2A per minute for TGHT and -1A min for TBHT

TGHT = 430 A, 7.3 V   (current actually fluctuates between 428 and 433 A since new power supply

TBHT = 233A, 4.0V  (set to 230 but displays 233) 

Thursday, October 21, 2021, 10:02

10 TaC coated Ta caps, wrapped in graphite foil.

2 TaC coated Ta springs .

All mounted inside a target boat with enclosed ends.

Good vacuum = 3.0 e-3 Torr

Bad vacuum = 5.0 e-2 Torr

Will heat up to 1800-1900 C and keep at Temp for four hours

OMEGA slope = 0.990

*Note that the turbo pump has been replaced and this is the first EVAP2 operation after replacement*

Thursday, October 21, 2021, 10:03

IGP1= 1.6 e-06 Torr

starting ramp up at  2 amp/min to 30 A on TGHT

Thursday, October 21, 2021, 10:46

Ramping to 40 A at 2A/min and will keep there for 20 minutes. 

Thursday, October 21, 2021, 11:19

 IGP1= 1.2e-05 Torr and dropping

Start ramp up to 400 A at 0.5A/min

Thursday, October 21, 2021, 18:58

Started ramping at 3A/min to 468A on TGHT

Thursday, October 21, 2021, 20:15

Current at 468.  Will keep there until pressure low enough.

Friday, October 22, 2021, 05:50

IGP1= 8.9 e-06 Torr

Start ramp down at -2A/min

 Monday, October 25, 2021, 11:47

Upon examination the caps and springs did not appeared coated.  The camera was not online so the current used was based on previous elogs.  It may have evaporated TaC due to over temperature.

The materials will be cleaned, recoated and resintered.