Tuesday, May 07, 2024, 06:16

TP was swapped on previous day (May 6th)

protective screen installed.

Loaded 9 TaC coated end caps (groups of 4 and 5) and 2 TaC coated springs.

OMEGA Slope 0.99

Will heat to 1850-1900 C and hold for 4 hours

Good Vac = 5.0e-4 Torr

Bad Vac= 5.0 e-02 Torr

 Initial IGP1=6.7E-07 Torr

Monday, May 27, 2024, 07:09

Small graphite cartridge was loaded with SiC discs 240523-1 and 240523-2.  Discs produced without milling using PAA as a dispersant.

The coated container tube was wrapped in four Ta foil heatshields.

two Tac Coated springs at the ends in case plugs are pushed outwards.

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final TGHT current= ~400A (adjustable)

Heating autoramp 2A/min to 90 A

Then at 2A/min to 120A.

Good vacuum = 5.0 e-02 Torr

Bad vacuum = 5.0E-04 Torr

 IGP1 initial 4.8e-07 Torr

Monday, May 27, 2024, 09:13

Pressure started coming down.  Heat at 2A/min to 120A.

Monday, May 27, 2024, 10:21

Started ramp 2A/30s  to 400A will monitor temperature

stopped at 490A and will hold for 4  hours. 

Monday, May 27, 2024, 12:41

temperature started creeping up past 1870C so decreased current to 461A

Current temperature is 1842 C at 461A, 7.6V

Monday, May 27, 2024, 12:55

dropped current to 441 because temperature climbed to 1899 C

Monday, May 27, 2024, 15:08

final pressure IGP1 =9.9 e-07 Torr

OMEGA= 1830 C at 410 A (reduced as needed)

Start rampdown at -2A/min

Wednesday, May 29, 2024, 10:07

Final pressure is 2.7e-7 Torr

Wednesday, May 29, 2024, 14:42

Experiment failed.  Too hot probably.  Bad temperature readings.  Will repeat after redesigning experiment.

Wednesday, May 29, 2024, 22:52

Small graphite cartridge was loaded with SiC discs 240523-1 and 240523-2 and 220727-2 (baseline discs).  Test Discs produced without milling using PAA as a dispersant.

The coated container tube was wrapped in four Ta foil heatshields.

two Tac Coated springs at the ends in case plugs are pushed outwards.

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final TGHT current= ~400A (adjustable)

Heating autoramp 2A/min to 90 A

Then at 2A/min to 120A.

Good vacuum = 5.0 e-02 Torr

Bad vacuum = 5.0E-04 Torr

 IGP1 initial 4.8e-07 Torr

Wednesday, May 29, 2024, 22:54

Kept at 400 A for 4 hours. 

Starting autoramp down at -2A/min

Wednesday, June 05, 2024, 07:14

SiC discs loaded into tantalum tube.  New mixing (two types) and old mixing.

The coated container tube was wrapped in four Ta foil heatshields.

Tac Coated springs at the ends in case plugs are pushed outwards.

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:=* 0.980*

Target time at max temperature = 4 hours

Final TGHT current= ~400A (adjustable)

Heating autoramp 1A/min to 90 A

Then at 2A/min to 120A.

Good vacuum = 5.0 e-02 Torr

Bad vacuum = 5.0E-04 Torr

 IGP1 initia1.3e-06Torr

Wednesday, June 05, 2024, 11:04

Continuing to ramp at 2A/min to 350A

Wednesday, June 05, 2024, 12:22

Leaving at 369 A for 4 hours (until 4 pm).  Temperature readings do not appear good.

Wednesday, June 05, 2024, 16:01

Start rampdown at -2A/min

IGP1=2.0 e-6 Torr

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

Darwin Ortiz Rosales wrote:

Wednesday, April 26, 2023, 09:32 LP FEBIAD loaded with 367 TiC discs and 4 TiC removable discs for analyses 50 packs of 5 and the rest are singles TaC coated (sintered) springs placed at both ends Initial total Weight = 521.83 g Initial heating @ 1A/min to 400 A on TGHT and 280A on TBHT OMEGA slope = 0.99 Vacuum limits up to 200A:  3.0e-05 Torr -- 5.0e-04 Torr Vacuum limit up after 200A: 3.0e-05 Torr -- 5.5e-05 Torr No Ta heat-shields used Initial IGP1 = 4.1e-07 Torr Wednesday, April 26, 2023, 09:49 Starting initial ramp up to 200A on both TGHT and TBHT @ 1A/min Wednesday, April 26, 2023, 12:50 Around 120A on TGHT, the pressure started to slowly drop.  First outgassing done. Wednesday, April 26, 2023, 14:03 IGP1 = 6.0 e-05 Torr TGHT = 200 A, 2.7V TBHT = 200 A, 2.6 v OMEGA = Below lower limit Waiting for pressure to fall below 5e0-5 Torr.  Will change bad vacuum to 5.0e-05 Torr and then continue ramping @1A/min to 400 A on TGHT and 280 A on TBHT. Wednesday, April 26, 2023, 14:13 IGPI= 4.2 e-05 Torr starting ramping to 400 A on TGHT and 280A on TBHT  Wednesday, April 26, 2023, 14:26 The IGP1 pressure just fell below 3.0e-05 Torr and ramping has resumed Wednesday, April 26, 2023, 14:42 pressure hovering around good vacuum so very slow progress. Wednesday, April 26, 2023, 15:12 TGHT= 223 A, 3.1 V TBHT = 226 A, 3.0 V Set ramp rate is 1A/min but real rate is slightly less than 0.5A/min due to pressure fluctuation.

 Vacuum spike at 300A.

Currently:

TGHT= 316A, 4.6V

TBHT=283A, 3.9V

Wednesday, April 26, 2023, 18:18 Ramping TBHT down from 280A to 270A

Darwin Ortiz Rosales wrote:

John Wong wrote: Carla Babcock wrote: Darwin Ortiz Rosales wrote: Wednesday, April 26, 2023, 09:32 LP FEBIAD loaded with 367 TiC discs and 4 TiC removable discs for analyses 50 packs of 5 and the rest are singles TaC coated (sintered) springs placed at both ends Initial total Weight = 521.83 g Initial heating @ 1A/min to 400 A on TGHT and 280A on TBHT OMEGA slope = 0.99 Vacuum limits up to 200A:  3.0e-05 Torr -- 5.0e-04 Torr Vacuum limit up after 200A: 3.0e-05 Torr -- 5.5e-05 Torr No Ta heat-shields used Initial IGP1 = 4.1e-07 Torr Wednesday, April 26, 2023, 09:49 Starting initial ramp up to 200A on both TGHT and TBHT @ 1A/min Wednesday, April 26, 2023, 12:50 Around 120A on TGHT, the pressure started to slowly drop.  First outgassing done. Wednesday, April 26, 2023, 14:03 IGP1 = 6.0 e-05 Torr TGHT = 200 A, 2.7V TBHT = 200 A, 2.6 v OMEGA = Below lower limit Waiting for pressure to fall below 5e0-5 Torr.  Will change bad vacuum to 5.0e-05 Torr and then continue ramping @1A/min to 400 A on TGHT and 280 A on TBHT. Wednesday, April 26, 2023, 14:13 IGPI= 4.2 e-05 Torr starting ramping to 400 A on TGHT and 280A on TBHT  Wednesday, April 26, 2023, 14:26 The IGP1 pressure just fell below 3.0e-05 Torr and ramping has resumed Wednesday, April 26, 2023, 14:42 pressure hovering around good vacuum so very slow progress. Wednesday, April 26, 2023, 15:12 TGHT= 223 A, 3.1 V TBHT = 226 A, 3.0 V Set ramp rate is 1A/min but real rate is slightly less than 0.5A/min due to pressure fluctuation.  Vacuum spike at 300A. Currently: TGHT= 316A, 4.6V TBHT=283A, 3.9V Wednesday, April 26, 2023, 18:18 Ramping TBHT down from 280A to 270A  Wednesday, April 26, 2023, 22:12 TGHT = 400A, 6.1V; TBHT = 274A/3.7V. Temp is holding sturdy ~1100 C and will leave it overnight. Pressure is coming down, currently at 8.8 e-6 Torr.  See attachment for the overview.  TGHT will continue to ramp up tomorrow morning; check the pressure to ensure it has come down below 5e-6 Torr before proceeding.  Refer to the instructions for details.         Thursday, April 27, 2023, 06:27 IGP1= 1.7e-06 Torr OMEGA= 1097 C TGHT= 400A, 6.2V TBHT= 273A, 3.7 V Starting ramp up of TGHT @0.2A/min set to 550A

 Reached 550A on TGHT (paused there until I realized it was stopped) then resumed ramping to 580A at 0.2A/min. Saw both vacuum spikes before 550A. Attaching screenshot from John.

Purpose: Sinter one sample of each of TiC, VC, Cr3C2, ZrC, NbC, Mo2C, TaC, and WC on 5x10 mm tantalum foil to see if the samples are usable for SEM.

Samples were prepared using a solution of PEG (2.56 g), PVB (2.45 g), paraffin oil (1.12 g), MEK (15 mL), and EtOH (23 mL). Slurries made using 0.0013 mol of each carbide with ~230 uL of the solution. Applied via paintbrush onto 5x10 mm tantalum foil. 

The samples were placed directly on the target boat, no graphite layer between. We will check to see if the tantalum foil fuses to the boat or not.

Currently (May 29th), the chamber is still pumping down. John and I will continue the procedure tomorrow.

 Pressure down to 7.1e-7 Torr. Water valve to heat shield was opened; pressure remained stable. 

Current turned up to 40 A for now.  Will increase at 2 A/min up to 500 A over the weekend, then on Monday we will turn it up to 600 A and check the temperature. 

Auto-ramp started. Max current = 500 A, voltage = 11.05 V. Current is being increased at 2 A/min. In the first 20 minutes, the pressure went up to about 10E-6 T, but has slowly decreased since then. Everything looks ok. The system will be left until Monday morning (June 9th). 

Manually changed current from 500 to 615 A, monitoring the temperature. Temperature went from 1657 C up to 1838 C. Pressure increased up to 7.2e-7 T. Samples should be left for about 4 hours (615 A started just before 13:00), then the goal is to ramp current back to zero.

 Target boat is now being cooled at 1 A/min from the starting point (616 A) down to 0 A. 

Temperature measurements in progress this week for Ta HP-SIS.

See attachment for the current settings and rampings of the TGHT/TBHT  for the temperature measurements taken on  Jan. 9-10, 2016 .

Note: TBHT PS tripped off on Jan. 9, 2016 (see first page of the attached file) and couldn't turn it ON again over the week-end.

Started Ta#47 heating at Evap2 using the autoramp program. The TGHT current is setup to go to 300A (for now) and the TBHT to 230A (final value).

Anders Mjos wrote:

Laura Lambert wrote: Aurelia Laxdal wrote: Started Ta#47 heating at Evap2 using the autoramp program. The TGHT current is setup to go to 300A (for now) and the TBHT to 230A (final value).  Monday, March 14, 2016, 09:20 One thermocouple was not welded on correctly and is not working.  Cooling evap2 back down, to remove target and re-weld thermocouple. Once thermocouple replaced, will ramp back up and continue with tests/ conditioning of target.    Monday, March 14, 2016, 13:12: Stopped turbo pump

 After EVAP2 was vented the thermocouple problem was fixed: it was the wire at on connector inside the box not making proper contact. The lid of the heat shield was also replaced since the one initially mounted had no holes, so one couldn't see the center block. Restarted pumping down at 4:30pm. Just started again the autoramp program: TGHT set to 300A (for the time being) and TBHT to 230A. Temperature measurements will resume tomorrow morning.