Tuesday, June 23, 2015, 12:21

Target container is loaded with 485 discs of SiC with packed length of 17.4cm. 

Container is wrapped with 3 Ta-heat shields and previously coated/sintered with TaC.

Chamber is currently being pumped down

TGHT will be ramped up to 800A, ~1800C, and TBHT is limited to 230A max.

 Tuesday, June 23, 2015, 15:53

HS valves are open, no leaks detected.

TGHT stepped up to 70A, pressure is currently at 4.17e-5 torr and coming up. 

Initiated auto-ramping at 0.5A/min for both TGHT and TBHT: good vac at 3.0e-5, bad vac at 4.0e-5 Torr.

 Wednesday, June 24, 2015, 00:03

Stopped auto-ramping about 2 hours ago.  

Manual stepped up TGHT to 73A.  Vac is stabilizing at 5e-8 Torr.  Will keep it at that current over night.

 Wednesday, June 24, 2015, 07:41

Vac has come down to 3.6e-6 Torr.

Continue to step up TGHT...

 Wednesday, June 24, 2015, 23:52

It has been a super long day operating the evaporator and finally the target is up to 1800C.  Vac is coming down from 2.e-5 Torr. 

TGHT is at 790A/12.61V, DV at 6.60V, TBHT at 230A/3.57V.  Omega temp reader is at 1680C - that's due to the window being coated with SiC, as expected. 

Target will continue heated at that current for over night, and will start the cooling process next AM. 

Thursday, June 25, 2015, 06:18  

Target is holding pretty well over night.  Vac is coming down to 1.6e-6 Torr. 

Initiated cooling down at 2A/min. 

John Wong wrote:

Tuesday, June 23, 2015, 12:21 Target container is loaded with 485 discs of SiC with packed length of 17.4cm.  Container is wrapped with 3 Ta-heat shields and previously coated/sintered with TaC. Chamber is currently being pumped down TGHT will be ramped up to 800A, ~1800C, and TBHT is limited to 230A max.  Tuesday, June 23, 2015, 15:53 HS valves are open, no leaks detected. TGHT stepped up to 70A, pressure is currently at 4.17e-5 torr and coming up.  Initiated auto-ramping at 0.5A/min for both TGHT and TBHT: good vac at 3.0e-5, bad vac at 4.0e-5 Torr.  Wednesday, June 24, 2015, 00:03 Stopped auto-ramping about 2 hours ago.   Manual stepped up TGHT to 73A.  Vac is stabilizing at 5e-8 Torr.  Will keep it at that current over night.  Wednesday, June 24, 2015, 07:41 Vac has come down to 3.6e-6 Torr. Continue to step up TGHT...  Wednesday, June 24, 2015, 23:52 It has been a super long day operating the evaporator and finally the target is up to 1800C.  Vac is coming down from 2.e-5 Torr.  TGHT is at 790A/12.61V, DV at 6.60V, TBHT at 230A/3.57V.  Omega temp reader is at 1680C - that's due to the window being coated with SiC, as expected.  Target will continue heated at that current for over night, and will start the cooling process next AM.  Thursday, June 25, 2015, 06:18   Target is holding pretty well over night.  Vac is coming down to 1.6e-6 Torr.  Initiated cooling down at 2A/min.

 Thursday, June 25, 2015, 16:09

Vented in air and took out this afternoon.

Target looks good [see photos]

Window for OMEGA fully coated from outgassing of target materials

Tuesday, August 18, 2015, 15:53

Target consists of 505 discs.

Total packed length 3.4cm.

Total mass 75.2772g.

Re foil inserted.

3x Ta Heat shields.

No endcaps inserted.

Chamber currently pumping down.

TBHT will be ramped up to 230A at 1.0A/min.

TGHT will be ramped up to 1800C, auto ramp to 600A at 2.0A/min [estimated final value of 720A according to elog ID 184]

*Note: Turbo Pump is on low speed

 Wednesday, August 19, 2015, 10:15

IGP1 = 8.3e-7 Torr.

Tapped up manually to 35A.

Initiating auto-ramp.

Wednesday, August 19, 2015, 15:55  

IGP1 = 3.3e-6 Torr.

TBHT reached max setpoint of 230A

TGHT reached max setpoint of 600A

OMEGA = 1554C

Increasing final setpoint of TGHT to 700A and re-initiating auto-ramp.

Laura Lambert wrote:

Tuesday, August 18, 2015, 15:53 Target consists of 505 discs. Total packed length 3.4cm. Total mass 75.2772g. Re foil inserted. 3x Ta Heat shields. No endcaps inserted. Chamber currently pumping down. TBHT will be ramped up to 230A at 1.0A/min. TGHT will be ramped up to 1800C, auto ramp to 600A at 2.0A/min [estimated final value of 720A according to elog ID 184] *Note: Turbo Pump is on low speed  Wednesday, August 19, 2015, 10:15 IGP1 = 8.3e-7 Torr. Tapped up manually to 35A. Initiating auto-ramp. Wednesday, August 19, 2015, 15:55   IGP1 = 3.3e-6 Torr. TBHT reached max setpoint of 230A TGHT reached max setpoint of 600A OMEGA = 1554C Increasing final setpoint of TGHT to 700A and re-initiating auto-ramp.

 Wednesday, August 19, 2015, 17:13

TGHT reached to 700A/10.5V, direct voltage at 5.2V, and temp measured at both ends at 1755C.  Vac is coming down from 4.2e-6 Torr. 

Stepping up TGHT to reach 1800C

Wednesday, August 19, 2015, 17:22

Increased TGHT to 722A/11.3V (direct voltage at 5.48V) to reach 1800C (consistant with the heating curve as for the previous HPTa target, elog 184)

Will continue to condition the target at this temperature for overnight. 

Cooling down can be initiated tomorrow morning at 2A/min --- Please measure the target temperature from the new window port before cooling it down.

John Wong wrote:

Laura Lambert wrote: Tuesday, August 18, 2015, 15:53 Target consists of 505 discs. Total packed length 3.4cm. Total mass 75.2772g. Re foil inserted. 3x Ta Heat shields. No endcaps inserted. Chamber currently pumping down. TBHT will be ramped up to 230A at 1.0A/min. TGHT will be ramped up to 1800C, auto ramp to 600A at 2.0A/min [estimated final value of 720A according to elog ID 184] *Note: Turbo Pump is on low speed  Wednesday, August 19, 2015, 10:15 IGP1 = 8.3e-7 Torr. Tapped up manually to 35A. Initiating auto-ramp. Wednesday, August 19, 2015, 15:55   IGP1 = 3.3e-6 Torr. TBHT reached max setpoint of 230A TGHT reached max setpoint of 600A OMEGA = 1554C Increasing final setpoint of TGHT to 700A and re-initiating auto-ramp.    Wednesday, August 19, 2015, 17:13 TGHT reached to 700A/10.5V, direct voltage at 5.2V, and temp measured at both ends at 1755C.  Vac is coming down from 4.2e-6 Torr.  Stepping up TGHT to reach 1800C Wednesday, August 19, 2015, 17:22 Increased TGHT to 722A/11.3V (direct voltage at 5.48V) to reach 1800C (consistant with the heating curve as for the previous HPTa target, elog 184) Will continue to condition the target at this temperature for overnight.  Cooling down can be initiated tomorrow morning at 2A/min --- Please measure the target temperature from the new window port before cooling it down.

 Thursday, August 20, 2015, 08:27

OMEGA = 1830C

Internal temperature using Mikron taken from the second 'new' view port: Hottest point on target leg = 2250C; hottest point on target material discs inside container = 1830C.

IGP1 = 1.5e-6 Torr.

EVAP2 has been sitting at max setpoints for ~15hours.

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

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote: Tuesday, August 18, 2015, 15:53 Target consists of 505 discs. Total packed length 3.4cm. Total mass 75.2772g. Re foil inserted. 3x Ta Heat shields. No endcaps inserted. Chamber currently pumping down. TBHT will be ramped up to 230A at 1.0A/min. TGHT will be ramped up to 1800C, auto ramp to 600A at 2.0A/min [estimated final value of 720A according to elog ID 184] *Note: Turbo Pump is on low speed  Wednesday, August 19, 2015, 10:15 IGP1 = 8.3e-7 Torr. Tapped up manually to 35A. Initiating auto-ramp. Wednesday, August 19, 2015, 15:55   IGP1 = 3.3e-6 Torr. TBHT reached max setpoint of 230A TGHT reached max setpoint of 600A OMEGA = 1554C Increasing final setpoint of TGHT to 700A and re-initiating auto-ramp.    Wednesday, August 19, 2015, 17:13 TGHT reached to 700A/10.5V, direct voltage at 5.2V, and temp measured at both ends at 1755C.  Vac is coming down from 4.2e-6 Torr.  Stepping up TGHT to reach 1800C Wednesday, August 19, 2015, 17:22 Increased TGHT to 722A/11.3V (direct voltage at 5.48V) to reach 1800C (consistant with the heating curve as for the previous HPTa target, elog 184) Will continue to condition the target at this temperature for overnight.  Cooling down can be initiated tomorrow morning at 2A/min --- Please measure the target temperature from the new window port before cooling it down.    Thursday, August 20, 2015, 08:27 OMEGA = 1830C Internal temperature using Mikron taken from the second 'new' view port: Hottest point on target leg = 2250C; hottest point on target material discs inside container = 1830C. IGP1 = 1.5e-6 Torr. EVAP2 has been sitting at max setpoints for ~15hours. Initiated auto-cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively.

 Thursday, August 20, 2015, 17:14

Target was removed the the evaporator and inspected.  It looks good! 

Ta-heat shields are removed. 

End caps are inserted but need to be expended.

Ready for assembly.

 Wednesday, December 16, 2015, 10:09

Target consists of 505 discs.

Total packed length 3.4cm.

*same parameters at Ta#46*

Total mass of target materials 53.9381g [4 packs of 20 with Ta wire + 425 single discs].

3 x Ta Heat shields.

No Re foil inserted.

No endcaps inserted.

Chamber pumped down overnight.

IGP1 = 5.1e-7 Torr.

Tapped up manually to 35A.

IGP1 = 5.2e-7 Torr.

Vacuum stable, initiating auto-ramp.

TBHT will be ramped up to 230A at 1.0A/min.

TGHT will be ramped up to 1800C, auto ramp to 600A at 2.0A/min [estimated final value of 720A according to elog ID 239]

 Wednesday, December 16, 2015, 15:08

TBHT reached max setpoint of 230A, 3.3V

TGHT = 600A, 8.9V

IGP1 = 1.1e-6 Torr.

OMEGA = 1543C

Increasing final setpoint of TGHT to 700A and re-initiating auto-ramp.

 Wednesday, December 16, 2015, 16:02

TGHT = 700A, 10.6V

IGP1 = 2.1e-6 Torr.

OMEGA = 1740C

Tapping up manually to 1800C.

 Wednesday, December 16, 2015, 16:28

TGHT = 730A, 11.2V

Vacuum is coming down from IGP1 = 2.6e-6 Torr.

OMEGA = 1800C

Will condition the target at 1800C overnight and ramp down in the morning.

 Thursday, December 17, 2015, 09:31

OMEGA = 1802C on right side

Temp on leg of left side = 2150C, the hottest point - measured with the Mikron pyrometer.

 Friday, December 18, 2015, 08:53

Evap2 remained at 1800C for ~26.5hrs

Auto-ramped down to TGHT = 300A and TBHT = 90A at a rate of 2.0A/min and 1.0A/min respectively.

Conditioning complete.

TGHT will be ramped up later today for emissivity measurements.

 Monday, January 04, 2016, 11:21

the following was performed by aurelia.

emissivity measurements were taken late december.

evap2 was cooled down and left under vacuum over the xmas break.

currently ramping back up for more emissivity measurements.

 Friday, January 08, 2016, 10:47

Aurelia done measurements.

vented and opened this morning.

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.

Aurelia Laxdal wrote:

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

 Friday, January 08, 2016, 10:49

Rh foil added.

endcaps inserted and expanded.

total length of target with end caps = 3.45cm

spot weld one thermocouple onto center block and one thermocouple onto target leg [left side wrt ionizer tube into page].

 see elog id# 268 for more info regarding measurements taken and state of TBHT power supply...

 Wednesday, May 25, 2016, 11:37

Container coated with TaC using 'flushing technique' [cleaned ionizer tube with acetone, so no coating inside ionizer tube]

Wrapped with 2 x Ta heat shields - one full height of Ta foil wrapped around cooling fins twice

Currently pumping down in evap2

 Thursday, May 26, 2016, 09:28

Tapped up manually to 40A

IGP1 = 6.6e-7 Torr

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

Final setpoints for TGHT = 650A and TBHT = 230A

Once max setpoints reached will continue to tap up manually while monitoring temperature to 1900C

Laura Lambert wrote:

Wednesday, May 25, 2016, 11:37 Container coated with TaC using 'flushing technique' [cleaned ionizer tube with acetone, so no coating inside ionizer tube] Wrapped with 2 x Ta heat shields - one full height of Ta foil wrapped around cooling fins twice Currently pumping down in evap2  Thursday, May 26, 2016, 09:28 Tapped up manually to 40A IGP1 = 6.6e-7 Torr Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints for TGHT = 650A and TBHT = 230A Once max setpoints reached will continue to tap up manually while monitoring temperature to 1900C

 Tuesday, May 31, 2016, 11:09

TGHT at 615A/9.08V, temp = 1610C.  Vacuum at 1.8e-7 Torr. 

Tapping up TGHT to reach 1900C

 Tuesday, May 31, 2016, 12:04

TGHT at 765A/11.90V.  Temp at 1900C.  Pressure is coming down from 8.7e-7Torr. 

Will keep at this temperature for a day.

 Wednesday, June 01, 2016, 15:22

Temperature has been stable at 1900C.  Pressure is coming down from 3.4e-7 Torr. 

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

 Friday, June 03, 2016, 12:10

TGHT/TBHT at 0A.  Target can be remained under vacuum until Monday.

 Monday, June 06, 2016, 16:54

Target container was inspected; it looks good

 Thursday, June 09, 2016, 15:39

First target using beta-SiC material!

Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs]

Target packed length = 16cm. 

Mass of 533 discs SiC(green)  = 53.8758g

Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place.

Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A. 

Chamber is currently being pumped down. 

Friday, June 10, 2016, 13:24

HS water valves opened, no leaks detected.

Tapping up manually to 70A...

Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A

Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.

 Friday, June 10, 2016, 16:27

TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V. 

Pressure stabilized at 5.5e-5 Torr.

Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.

John Wong wrote:

Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.

 Monday, June 13, 2016, 09:51

TGHT = 425A, 5.65V

TBHT = 225A, 3.7V

IGP1 = 8.7e-6 Torr.

Increasing ramping rate to 1.0A/min...

 Monday, June 13, 2016, 15:56

Tapped up manually from 520A to 1800C

Extrapolated data on graph to determine correct current required to reach desired max temperature.

Will remain at 1800C for ~48hrs

See attachements for excel sheet and screenshot of striptool.

Laura Lambert wrote:

John Wong wrote:   Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.    Monday, June 13, 2016, 09:51 TGHT = 425A, 5.65V TBHT = 225A, 3.7V IGP1 = 8.7e-6 Torr. Increasing ramping rate to 1.0A/min...  Monday, June 13, 2016, 15:56 Tapped up manually from 520A to 1800C Extrapolated data on graph to determine correct current required to reach desired max temperature. Will remain at 1800C for ~48hrs See attachements for excel sheet and screenshot of striptool.

 Wednesday, June 15, 2016, 17:54

TGHT at 710A, 11.35V.  TBHT at 230A/3.86V. 

Omega reading droppd to 1130C due to coating on windows. 

Ionizer tube was measured (center) at around 1900C

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

Samples will be collected prior to cleaning the windows.

NEXT:  Conditioning.

John Wong wrote:

Laura Lambert wrote: John Wong wrote:   Laura Lambert wrote:  Thursday, June 09, 2016, 15:39 First target using beta-SiC material! Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 53.8758g Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place. Sintering temp = 1800C, TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.  Friday, June 10, 2016, 13:24 HS water valves opened, no leaks detected. Tapping up manually to 70A... Auto ramp will be set for TGHT = 0.2A/min to a final setpoint of 520A Auto-ramp for TBHT = 0.1A/min to a final setpoint of 230A.      Friday, June 10, 2016, 16:27 TGHT stepped up to 70A/0.55V.  TGHT at 50A/0.62V.  Pressure stabilized at 5.5e-5 Torr. Initiated auto ramping.  TGHT at 0.2A/min --> 520A.  TBHT at 0.1A/min --> 230A.    Monday, June 13, 2016, 09:51 TGHT = 425A, 5.65V TBHT = 225A, 3.7V IGP1 = 8.7e-6 Torr. Increasing ramping rate to 1.0A/min...  Monday, June 13, 2016, 15:56 Tapped up manually from 520A to 1800C Extrapolated data on graph to determine correct current required to reach desired max temperature. Will remain at 1800C for ~48hrs See attachements for excel sheet and screenshot of striptool.    Wednesday, June 15, 2016, 17:54 TGHT at 710A, 11.35V.  TBHT at 230A/3.86V.  Omega reading droppd to 1130C due to coating on windows.  Ionizer tube was measured (center) at around 1900C Cooling down at 2A/min for TGHT, 1A/min for TBHT.  Samples will be collected prior to cleaning the windows. NEXT:  Conditioning.

Thursday, June 16, 2016, 09:29

vented in air and opened up this morning.

took some samples to be tested.

 Thursday, June 16, 2016, 10:59

Previously sintered over weekend [see elog i.d 306]

Target container contains 450 discs of SiC [4 x 5 packs + 430 single discs]

Target packed length = 16cm. 

Mass of 533 discs SiC(green)  = 53.8758g

Container is wrapped with 3 heatshields; no end caps are inserted yet - coated spring inserted both sides to hold discs in place.

Conditioning temp = 1800C.

TGHT max = 710A according to sintering data.  TBHT max = 230A. 

Chamber is currently being pumped down. 

 Thursday, June 16, 2016, 15:43

Target was not removed from evap2 after sintering, vented and cleaned windows only.

HS water valves already open.

Stepped up manually to 70A, vacuum stable.

Initiated auto-ramp at 1.0A/min for the TGHT and 0.5A/min for the TBHT with max setpoints of 600A and 230A respectively.

TGHT = 118A, 0.9V

TBHT = 90A, 1.1V

IGP1 = 7.3e-7 Torr

 Friday, June 17, 2016, 12:14

TGHT has been tapped up manually to reach max desired temperature of 1800C

TGHT = 690A, 10.85V

TBHT = 230A, 3.88V

IGP1 = 4.9e-7 Torr

This is a lower current than the current required to reach 1800C during the sintering process.

For sintering, the max current was determined via extrapolation of trendline from raw data due to interference of coating on window and unable to take reliable readings from OMEGA.

For this conditioning process ~1800C is reached on the OMEGA since the window is still ~un-coated.

Will remain at 690A, ~1800C for several days to maximize conditioning process.

See attachment for raw data.

 Monday, June 20, 2016, 09:01

At the end of the day on friday 17th, OMEGA read ~1750C - no change in the current or voltage, vacuum was stable, this was the max setpoints used to reach 1800C.

This morning OMEGA = 2040C

TGHT = 690A, 10.95V

vacuum stable at IGP1 = 1.8e-7 Torr.

Slightly more noticeable coating on window port, looks like a thin ink layer, still relatively thin coating [ see attached image]

Also attached is archive from over wknd to show vacuum stable, current unchanged and voltage negligibly changed [only gone up by ~0.1V]

 Friday, June 24, 2016, 13:52

Container has remained at max setpoints for 7 days.

Initiating auto-cool for TGHT @ 2.0A/min and for TBHT @ 1.0A/min.

Will vent chamber and remove from evap2 to pass off for assembly monday morning.

See attachment for updated excel on temperature readings for the conditioning process.

 Monday, June 27, 2016, 08:28

vented in air and removed this morning.

target looks good!

all discs remained nicely alligned.

discs expanded outwards ~1cm, pushed back in to keep target length at 16cm

no visible yellow crystals like previous SiC targets 

endcaps inserted and expanded.

Rh foil inserted.

Ta heat shield foils removed, fins look good.

see photos attached for pictures of target - post conditioning.

coating on window very hard to remove. looked like a light sharpy pen coating on window. ended up scratching off with acetone and screw driver. couldn't remove all of it...

 Tuesday, July 26, 2016, 16:50

loaded into evap2

pumped down, HS water valves opened, no leaks detected.

tapped up manually to 35A

vacuum stable = 3.8e-6 Torr

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

Final setpoints at 230A for the TBHT and 600A for the TGHT.

Final desired temperature = 1800C

 Wednesday, July 27, 2016, 09:20

IGP1 = 6.3e-7 Torr, vacuum stable.

TGHT = 232A, 2.7V

TBHT = 131A, 1.76V

Increasing ramping rate to 1.0A/min and 0.5A/min for the TGHT and TBHT respectively.

 Wednesday, July 27, 2016, 15:46

TGHT = 600A, 8.87V

TBHT = 230A, 3.7V

IGP1 = 1.37e-6 Torr

OMEGA = 1640C

Increased max TGHT voltage to 12V

Tapped up manually to OMEGA = 1810C

TGHT = 675A, 10.21V

IGP1 = 2.2e-6 Torr

Will remain at max setpoints for the rest of the week and cool down over weekend.

 Thursday, July 28, 2016, 08:34

TGHT = 675A, 10.41V

OMEGA = 1833C

Tapped down to 660A, 10.09V

OMEGA = 1805C

 Friday, July 29, 2016, 13:57

OMEGA = 1814C

TGHT = 660A, 10.16V

TBHT = 230A, 3.72V

IGP1 = 3.43e-7 Torr

evap2 has remained at max setpoints for ~42hrs

conditioning complete.

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

 Tuesday, August 02, 2016, 13:39

vented in air and removed from evap2 this morning.

target looks good!

 Wednesday, September 07, 2016, 14:45

Container was previously coated with TaC solution and wrapped with 1-full length layer of Ta- heat shield around the fins.  

Chamber is being pumped down.  Vac at 5.6e-7 Torr before HS water valves were open; no leaks were detected. 

Sintering Temperature 1900C (Omega slope @ 0.98); expected TGHT ~765A/11.90V, TGHT max at 230A.

 Thursday, September 08, 2016, 18:14

At about 1600C, it was observed that the coating inside the tube seems to chip off (see attachment 1).

TGHT was ramped up to 745A/11.85V and TBHT to 230A/3.25V.  Temperature measured on OMEGA/Mikron = 1914C/1881C; both instruments slopes set at 0.98.

Will remain at this TGHT current over night

Vac at 3.0e-6 Torr and coming down.

Friday, September 09, 2016, 11:01 

Target has been heated at the stable temperature at 1914C (for OMEGA) and 1881C (for Mikron) with current at 745A/11.94V (see attachment 2) for almost 19 hours. 

No fluctuation in p/s current or temperature was observed.  The ramping up process is captured and can be view from the link below:

https://www.dropbox.com/sh/9lgtin54o17ds6j/AABn1-XjvK44mm74TjqTAmvta?dl=0

Pressure at 1.07e-6 Torr. 

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

Continue to capture the cooling down process. 

 Friday, September 09, 2016, 15:17

 While the target container was cooling down, the chip-like particle began obvious (see attachment 3).  

Will inspect the container.. TGHT currently at 260A.

John Wong wrote:

Wednesday, September 07, 2016, 14:45 Container was previously coated with TaC solution and wrapped with 1-full length layer of Ta- heat shield around the fins.   Chamber is being pumped down.  Vac at 5.6e-7 Torr before HS water valves were open; no leaks were detected.  Sintering Temperature 1900C (Omega slope @ 0.98); expected TGHT ~765A/11.90V, TGHT max at 230A.  Thursday, September 08, 2016, 18:14 At about 1600C, it was observed that the coating inside the tube seems to chip off (see attachment 1). TGHT was ramped up to 745A/11.85V and TBHT to 230A/3.25V.  Temperature measured on OMEGA/Mikron = 1914C/1881C; both instruments slopes set at 0.98. Will remain at this TGHT current over night Vac at 3.0e-6 Torr and coming down. Friday, September 09, 2016, 11:01  Target has been heated at the stable temperature at 1914C (for OMEGA) and 1881C (for Mikron) with current at 745A/11.94V (see attachment 2) for almost 19 hours.  No fluctuation in p/s current or temperature was observed.  The ramping up process is captured and can be view from the link below: https://www.dropbox.com/sh/9lgtin54o17ds6j/AABn1-XjvK44mm74TjqTAmvta?dl=0 Pressure at 1.07e-6 Torr.  Cooling down TGHT at 2A/min and TBHT at 1A/min.  Continue to capture the cooling down process.   Friday, September 09, 2016, 15:17  While the target container was cooling down, the chip-like particle began obvious (see attachment 3).   Will inspect the container.. TGHT currently at 260A.

 Monday, September 12, 2016, 16:54

The TaC coating chipped off from the surface and didn't get sintered with the container.  (See attachment1). 

There are a few possible reasons why this happened:

1.  The coating was too think.  This may cause the TaC  layer to curl up while the heater was ramped up. 

2.  The coated material got brittle.  The container was flushed with TaC (probably a few weeks ago?) before it went through the sintering process.  Prolong exposure to air/light usually degrade the polymers viscoelasticity.

3.  TaC solution has got bad.  The particles can agglomerate over time and this can cause uneven surface.

4.  Combination of all... ???

Anyway, the chipped off TaC layer was gently scraped off with a stainless steel rod.  Then using kimwipes, i was able to remove most of the chipped off coating; it was not easy - especially trying to remove it from the inner tube.

Instead of "flushing" the tube with TaC, I decided to spray it with thin layer.  And using the air supply, I could quickly dry the coating and installed it back to the evaporator for 2nd Round sintering as we are approaching the deadline!

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