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.

 Friday, June 13, 2014, 14:53

Container is filled with 400 discs of Ta foils; target length = 5.2cm;

Total mass ( Ta foils + wire) = 45.92g

No Ta foil heat shield.

No caps inserted.

Chamber pumped down this morning.

HS cooling water valves opened, no leaks detected.

IG @ 5.8e-6 Torr.

TGHT max = 580A

TBHT max = 230A

Ramping rate 0.2A/min.

 Monday, June 16, 2014, 11:46

TGHT and TBHT reached their respective 580A and 230A over the weekend.

IGP1 currently at 3.2e-7 Torr.

Internal temp [measured using mikron, right side of EVAP2, pointed at discs inside] = 1375C

Laura Lambert wrote:

Friday, June 13, 2014, 14:53 Container is filled with 400 discs of Ta foils. No Ta foil heat shield. No caps inserted. Chamber pumped down this morning. HS cooling water valves opened, no leaks detected. IG @ 5.8e-6 Torr. TGHT max = 580A TBHT max = 230A Ramping rate 0.2A/min.  Monday, June 16, 2014, 11:46 TGHT and TBHT reached their respective 580A and 230A over the weekend. IGP1 currently at 3.2e-7 Torr. Internal temp [measured using mikron, right side of EVAP2, pointed at discs inside] = 1375C

 Monday, June 16, 2014, 17:21

Further stepping up TGHT to 650A.

Temperature measured on target discs = 1542C. Vac @ 3.28e-7 Torr.

Initiate cooling down process; 2A/min for TGHT; 1A/min for TBHT

John Wong wrote:

Laura Lambert wrote:  Friday, June 13, 2014, 14:53 Container is filled with 400 discs of Ta foils. No Ta foil heat shield. No caps inserted. Chamber pumped down this morning. HS cooling water valves opened, no leaks detected. IG @ 5.8e-6 Torr. TGHT max = 580A TBHT max = 230A Ramping rate 0.2A/min.  Monday, June 16, 2014, 11:46 TGHT and TBHT reached their respective 580A and 230A over the weekend. IGP1 currently at 3.2e-7 Torr. Internal temp [measured using mikron, right side of EVAP2, pointed at discs inside] = 1375C    Monday, June 16, 2014, 17:21 Further stepping up TGHT to 650A. Temperature measured on target discs = 1542C. Vac @ 3.28e-7 Torr. Initiate cooling down process; 2A/min for TGHT; 1A/min for TBHT

 Tuesday, June 17, 2014, 10:08

TGHT and TBHT reached 0A last night.

Turned off EVAP2

Venting chamber

Process Complete

Wednesday, August 21, 2013, 12:28

Container is filled with 400 discs of Ta foils, and wrapped with 3 layers of Ta heat shields.

No caps are inserted during the conditioning. 

Chamber is currently being pumped down. 

 Wednesday, August 21, 2013, 15:54

HS cooling water valves opened, no leaks were detected.

IG @ 2.9e-6 Torr.

Heating setting:

TGHT max = 820A,

TBHT max = 230A

ramping rate 2A/min.

 Thursday, August 22, 2013, 12:45

TGHT/TBHT reached to 820A/230A, respectively. 

So much out-gassing was observed at the max currents.  (see attachment#1).

TGHT/TBHT are ramping down at 4A/min. 

Chamber will be vented in air.

The target will will be inspected.

More info later...

 Thursday, August 22, 2013, 16:44

Target was removed from the evaporator and inspected.

The container and the Ta materials look OK. 

The outgassing could be from the Ta-heat shields; they look burnt and brittle.

Overall, the target is good.

Wednesday, August 06, 2014, 15:59

Target consists of 400 Ta discs. 

Total packed length 4.5cm

Total mass 47.490g.

Re foil inserted.

Wednesday, August 06, 2014, 16:07

Chamber is currently being pumped down.

No Ta heat-shield wrapped (Want to check the temperature without it) 

One end-cap inserted on left (wrt ionizer into the page).

TGHT and TBHT will be ramped up to 820A/230A at 2A/min.

 Wednesday, August 06, 2014, 18:07

Vacuum at 2.3e-6 Torr.  HS water valve opened.  No leaks.

Initiated auto-ramping.

 Thursday, August 07, 2014, 11:39

Target has been heated for 11hrs at TGHT/TBHT = 820A/230A.

Temperature measured with pyrometer:

Target leg = 1600C + (250 correction for e=0.25) = 1850C

Inside target material = dark, temp can't be measured.

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

John Wong wrote:

Wednesday, August 06, 2014, 15:59 Target consists of 400 Ta discs.  Total packed length 4.5cm Total mass 47.490g. Re foil inserted. Wednesday, August 06, 2014, 16:07 Chamber is currently being pumped down. No Ta heat-shield wrapped (Want to check the temperature without it)  One end-cap inserted on left (wrt ionizer into the page). TGHT and TBHT will be ramped up to 820A/230A at 2A/min.  Wednesday, August 06, 2014, 18:07 Vacuum at 2.3e-6 Torr.  HS water valve opened.  No leaks. Initiated auto-ramping.  Thursday, August 07, 2014, 11:39 Target has been heated for 11hrs at TGHT/TBHT = 820A/230A. Temperature measured with pyrometer: Target leg = 1600C + (250 correction for e=0.25) = 1850C Inside target material = dark, temp can't be measured. Cooling down at 2A/min for TGHT and 1A/min TBHT.

 Friday, August 08, 2014, 15:14

Vented in air and opened up up this morning.

Endcaps inserted and expanded.

Rh foil and salts added.

 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.

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.

 Friday, December 16, 2016, 14:08

Target consists of 470 discs.

Total packed length 3.4cm [exactly 7.8cm space on both sides]

Total mass 45.9091g [Incl foils + Ta wire on 6 packs]

Target consists of 350 single discs and 6x20 packs of Ta discs

Discs in target are arranged as follows: 1pack / 75singles / 1pack / 100singles / 2packs / 100singles / 1pack / 75singles / 1pack

3x Ta Heat shields.

LP-FEBIAD container with large center block.

No endcaps inserted, no Rh foil inserted.

Chamber currently pumping down.

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

TGHT will be ramped up to 350A at 2.0A/min.

Final desired temperature = 1900C

 Friday, December 16, 2016, 14:32

 Monday, December 19, 2016, 11:52

Tapped up manually to ~1900C [see attached excel for details on data collected - interesting temperature fluctuations]

 Will remain at max setpoints for min 4hrs then auto-cool

 Monday, December 19, 2016, 15:20

Target has remained at max setpoints for just over 4hrs

TGHT = 520A, 8.67V

OMEGA = 1820C

IGP1 = 5.2e-7 Torr

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

 Tuesday, December 20, 2016, 11:52

Vented in air and opened up this morning.

Looks like the windows was coated in evap2, unsure if this was missed and coated before conditioning target or if this is from materials coming out during conditioning process...

Target looks good.

Endcaps inserted but not expanded.

Laura Lambert wrote:

Monday, August 08, 2016, 15:19 Previously sintered over weekend [see elog i.d 311] Target container contains 471 discs of SiC [6 x 5 packs + 441 single discs] Target packed length = 16cm.  Mass of 533 discs SiC(green)  = 52.7172g 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 = 450A.  TBHT max = 230A.  Chamber is currently being pumped down.   Monday, August 08, 2016, 16:38 Target was not removed from evap2 after sintering, vented and cleaned windows only. IGP1 = 5.5e-6 Torr Stepped up manually to 80A, vacuum stable. IGP1 = 3.2e-6 Torr Initiating auto-ramp at 0.2A/min for the TGHT and 0.1A/min for the TBHT.  Thursday, August 11, 2016, 14:14 Tues the TGHT reached ~280A via auto-ramp Evap2 was then tapped up manually to 480A/ ~1800C Temperature readings on OMEGA have fluctuated up and down during conditioning process which was also observed for SiC#33 Also consistent with SiC#33, a lower current was required to reach 1800C during the conditioning process compared to the sintering process. See attached link for data.  Tuesday, August 16, 2016, 16:25 TGHT remained at 480A, 9.2V for ~7 days. IGP1 = 6.5e-6 Torr OMEGA = 1470C [with window coating, so temperature reading compromised] Initiating auto cool at 2.0A/min and 1.0A/min for the TGHT and TBHT respectively. Wednesday, August 17, 2016, 13:40 Vented in air and opened this morning. Target broke   Target clearly heated to high. See attached snapshot of striptool from conditioning process. Will update later with photos of broken container

 Tuesday, August 30, 2016, 15:17

A better look at the p/s voltage over the course of the constant heating at 480A.  (see attachment).

The striptool shows the voltage was not giving a stable output.  There were multiple occasions that the voltage dropped and then recovered; the obvious was on Aug 16.  This indicates that  the target was breaking up.

Finally on Aug 17, the voltage dropped and never recovered again - that indicates the target was broken.

 Monday, August 08, 2016, 15:19

Previously sintered over weekend [see elog i.d 311]

Target container contains 471 discs of SiC [6 x 5 packs + 441 single discs]

Target packed length = 16cm. 

Mass of 533 discs SiC(green)  = 52.7172g

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 = 450A.  TBHT max = 230A. 

Chamber is currently being pumped down. 

 Monday, August 08, 2016, 16:38

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

IGP1 = 5.5e-6 Torr

Stepped up manually to 80A, vacuum stable.

IGP1 = 3.2e-6 Torr

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

 Thursday, August 11, 2016, 14:14

Tues the TGHT reached ~280A via auto-ramp

Evap2 was then tapped up manually to 480A/ ~1800C

Temperature readings on OMEGA have fluctuated up and down during conditioning process which was also observed for SiC#33

Also consistent with SiC#33, a lower current was required to reach 1800C during the conditioning process compared to the sintering process.

See attached link for data.

 Tuesday, August 16, 2016, 16:25

TGHT remained at 480A, 9.2V for ~7 days.

IGP1 = 6.5e-6 Torr

OMEGA = 1470C [with window coating, so temperature reading compromised]

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

Wednesday, August 17, 2016, 13:40

Vented in air and opened this morning.

Target broke  

Target clearly heated to high.

See attached snapshot of striptool from conditioning process.

Will update later with photos of broken container

 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...

 Friday, June 20, 2014, 11:14

Made from batch's: oct 23/2013, oct 31/2013 and june 2012

Total number of foils: 515 discs

Total mass of materials [incl graphite foils]: 64.7224g

Total length packed: 17.8cm

Container is wrapped with 3x Ta-heat shields.

Currently being pumped down.

 Friday, June 20, 2014, 14:56

HS cooling water valves opened, no leaks detected.

IGP1 = 6.2e-6 Torr

TGHT max = 820A/ 17V

TBHT max = 300A/ 5V

Stepping up manually to 40A

 Friday, June 20, 2014, 16:04

IGP1 = 8e-6 Torr

Slowly stepped up to 35A manually.

Vacuum has stabilized.

Initiating auto-ramp at 0.1A/min

Laura Lambert wrote:

Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min

 Friday, June 20, 2014, 16:16

Changing the heating current... 

From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process. 

For this process,

TGHT will ramp up to 600A and TBHT to 230A over the weekend. 

Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C. 

John Wong wrote:

Laura Lambert wrote:  Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min    Friday, June 20, 2014, 16:16 Changing the heating current...  From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process.  For this process, TGHT will ramp up to 600A and TBHT to 230A over the weekend.  Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C.

 Monday, June 23, 2014, 09:45

IGP1 = 5e-6 Torr

TGHT and TBHT are at ~200A

Increasing ramping rate to 0.2A/min

 Monday, June 23, 2014, 11:19

IGP1 = 6.9e-6 Torr

Increasing ramping rate to 2.0A/min

Monday, June 23, 2014, 12:09

JW:  Pressure went up too fast... lower the TGHT ramping up rate to 1A/min.

 Tuesday, June 24, 2014, 16:06

Increasing current with respect to temperature: See attached table

Laura Lambert wrote:

John Wong wrote: Laura Lambert wrote:  Friday, June 20, 2014, 11:14 Total number of foils: 515 discs Total mass of materials [incl graphite foils]: 64.7224g Total length packed: 17.8cm Container is wrapped with 3x Ta-heat shields. Currently being pumped down.  Friday, June 20, 2014, 14:56 HS cooling water valves opened, no leaks detected. IGP1 = 6.2e-6 Torr TGHT max = 820A/ 17V TBHT max = 300A/ 5V Stepping up manually to 40A  Friday, June 20, 2014, 16:04 IGP1 = 8e-6 Torr Slowly stepped up to 35A manually. Vacuum has stabilized. Initiating auto-ramp at 0.1A/min    Friday, June 20, 2014, 16:16 Changing the heating current...  From the previous SiC targets, TGHT was ramped up to 800A and yellow crystals were found; the end caps and target legs were also found broken (see my iPad).  This might be too hot for the Ta-boat to handle the sintering process.  For this process, TGHT will ramp up to 600A and TBHT to 230A over the weekend.  Then, the temperature will be measured.  The sintering temperature of SiC is ~1800 - 2000C.     Monday, June 23, 2014, 09:45 IGP1 = 5e-6 Torr TGHT and TBHT are at ~200A Increasing ramping rate to 0.2A/min  Monday, June 23, 2014, 11:19 IGP1 = 6.9e-6 Torr Increasing ramping rate to 2.0A/min Monday, June 23, 2014, 12:09 JW:  Pressure went up too fast... lower the TGHT ramping up rate to 1A/min.  Tuesday, June 24, 2014, 16:06 Increasing current with respect to temperature: See attached table

 Tuesday, June 24, 2014, 23:44

Target has been heated at 600A.  Local temperature measured on the right leg = 1814C. 

RGA/ striptool/temperature data can be found on this link: 

https://www.dropbox.com/sh/69memvh6fthodoz/AABZiSKAR9njhbqO4sBATVbla

Something interesting was observed about the out gassing of this target - the right window was coated when the temperature rose above 1500C (on the right end, could be hotter inside?) - see attachment.

I suspect this is Si vapour deposited on the window when the target heater got closed to the sintering temperature for SiC (1800 - 2000C).  

Once the chamber is vented, the coated window will be inspected and analyzed.  More details later...  

Initiate auto-cooling (slow cool down)  TGHT 1A/min; TBHT 0.5/min.  Chamber should be able for venting tomorrow afternoon.  

Monday, January 11, 2016, 15:25

Small center block LP-SIS container previously sintered with TaC coating

3x Ta heat shields

Container is loaded with 260 discs of SiC with a total length of 8.5cm

Loaded into evap2 and pumped down this morning

HS water valves opened up, no leaks detected

Tapped up manually to 30A

Vacuum stable

IGP1 = 1e-6 Torr

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

Final setpoints: 400A for the TGHT and 230A for the TBHT

Final desired temperature: 1700C

 Tuesday, January 12, 2016, 12:55

TGHT = 138A, TBHT = 80A

IGP1 =  7.7e-6 Torr.

Vacuum stable and coming down.

Increasing ramping rate to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.

 Wednesday, January 13, 2016, 09:32

TGHT reached 400A ~11.5hrs ago

TBHT reached 230A ~8hrs ago

OMEGA = 1400C

IGP1 = 1.75e-7 Torr

Tapping up manually to 1700C...

 Wednesday, January 13, 2016, 10:14

Previous temperature measurement of OMEGA = 1400C is wrong due to window port being coated with SiC [see attached photos]

Will remain at TGHT = 420A for 4hrs then cool down this afternoon

Wednesday, January 13, 2016, 14:29

Remained at max setpoints for 4.5hrs.

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

 Thursday, January 14, 2016, 09:47

Vented in air and opened up this morning

Target looks good

Will insert and expand endcaps this afternoon