Laura Lambert wrote:

Laura Lambert wrote: Laura Lambert wrote: Laura Lambert wrote: John Wong wrote: John Wong wrote: Laura Lambert wrote: Laura Lambert wrote: Laura Lambert wrote: Laura Lambert wrote: Laura Lambert wrote:  Monday, January 20, 2014, 16:32 A new target boat was sprayed with TaC coating and let dry this morning. The target boat is NOT wrapped with Ta-heat shield. The boat was installed in Evap#2, chamber is currently being pumped down overnight.    Tuesday, January 21, 2014, 11:10 Chamber was pumped down to ~2e-7 Torr. HS cooling water valves were opened, no leaks detected. TGHT was stepped up to 35A, voltage max set at 13V. TBHT currently @ 0A. Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 2.0A/min and max setpoint to 700A. Good vacuum: 3.00e-5 Torr, Bad vacuum 4.00e-5 Torr.    Tuesday, January 21, 2014, 11:51 Vacuum was grumpy and was well on it's way to tripping off [reached 5e-5 Torr], auto ramping was stopped at ~95A and quickly stepped down to 90A to avoid tripping it off. Allowed vacuum to settle back down to 2.3e-6 Torr. Auto ramping changed to 0.2A/min and re-started.  close-call!    Wednesday, January 22, 2014, 09:46 TGHT has been slowly ramping up overnight at a rate of 0.2A/min. IGP1 = 2.9e-7 Torr, TGHT = 342A; stepping ramping rate up to 2.0A/min.    Wednesday, January 22, 2014, 13:43 TGHT is sitting at 693A, IGP1 = 1.3e-6 Torr. Stepping up TGHT voltage up to 14V from 13.05V to reach the max current of 700A.    Wednesday, January 22, 2014, 15:09 TGHT reached to 700A/12.83V.  Local temperature on the boat surface was measured at ~1500C. Target will be heated for a few hours and will be cooled down later tonight. The chamber will be vented tomorrow and the boat will be inspected.    Wednesday, January 22, 2014, 18:09 After the boat was heated for ~4hrs, TGHT tripped off on IEVAP2:TBHT2 (see attachment #1, #2).  Tried clearing the water interlock via EPICS - failed to clear.  Checked the local water valves - ALL VALVES are OPEN  Tried closing and re-opening the IEVAP2:TBHT2 valves, interlock cleared after a few minutes.  Maybe a fault in the water signal.  If it happens again, the water signal should be replaced. Turned back on the power supply - TGHT current/voltage are holding.  Target boat may be OK! Chamber is a bit warm now.  Will allow time to cool down. Will vent the chamber tomorrow and the boat will be inspected.     Thursday, January 23, 2014, 16:18 Chamber vented overnight and was opened up this morning. Target boat not fully sintered [see attached photos]. Chamber currently being pumped down again in order to continue with sintering TaC coating. HS cooling water valves were opened, no leaks detected. Will ramp up to 700A again over the weekend.  Friday, January 24, 2014, 14:21 Chamber was pumped down to 1.7e-7 Torr. TGHT was stepped up to 35A, voltage max set at 14V. TBHT currently sitting at 0A. Waited 20min, vacuum consistently stable. Auto-ramp initiated at 2.0 A/min and max setpoint to 700A.    Monday, January 27, 2014, 10:05 TGHT reached 700A over the weekend. Measured temp @ 2000C. TGHT auto-cool inititated at 2.0A/min.    Tuesday, January 28, 2014, 11:53 Chamber cooled down overnight, vented and opened up this morning. Target boat still has a strip of green, still not fully sintered! [see attached photos]. Chamber currently being pumped down again to attempt sintering - round 3.

 Tuesday, January 28, 2014, 13:06

Discussed with Peter. Instead of re-sintering the whole boat by itself, end caps will be inserted for sintering and will be placed further down the boat where the sintering process appears complete.

 Tuesday, January 28, 2014, 15:43

The target containers end-caps were coated with TaC spray and let dry.

Each cap is wrapped with a small piece of graphite foil and inserted in the target boat. [see attached photo]

The chamber is currently being pumped down overnight.

 Wednesday, January 29, 2014, 11:32

Chamber was pumped down to 1.6e-7 Torr overnight.

HS cooling water valve opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 11.05V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 580A.

Good vacuum: 3.00e-5 Torr, Bad vacuum 4.00e-5 Torr.

 Thursday, January 30, 2014, 09:06

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 2.4e-7 Torr, TGHT = 283A; stepping ramping rate up to 2.0A/min.

 Thursday, January 30, 2014, 15:53

TGHT reached 580A at 11:45. Measured temp @1650C.

Initiating TGHT auto-cooling now at 2.0A/min.

 Friday, January 31, 2014, 09:04

Chamber cooled down overnight, vented and opened this morning.

Smooth run!

 Friday, January 31, 2014, 11:21

Opened up the end caps, turns out it wasn't such a smooth run...they're not fully sintered 

See attached photo comparison between fully sintered end cap [silver] and end cap from this run [green].

Will re-install and re-sinter next week.

 Wednesday, February 05, 2014, 11:34

End-caps re-installed into EVAP2

Target boat is wrapped with 3 x Ta heat-shield.

Chamber is currently being pumped down.

 Wednesday, February 05, 2014, 14:31

Chamber was pumped down to 5e-7 Torr this morning.

HS cooling water valve opened, no leaks detected.

TGHT was stepped up to 35A, voltage max set at 11.05V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 580A.

Good Vacuum: 3.00e-5 Torr, Bad vacuum 4.00e-5 Torr.

 Thursday, February 06, 2014, 09:06

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 1.1e-7 Torr, TGHT = 259A; stepping ramping rate up to 2.0A/min.

 Friday, February 07, 2014, 10:10

TGHT reached 580A yesterday. Measured internal temp @ 1500C.

Initiated TGHT auto-cooling this morning at 2.0A/min

 Tuesday, February 11, 2014, 13:30

Vented and opened chamber this morning.

Endcaps are toast  [see pictures attached]

Some of the endcaps broke/fried, others deformed-none useable.

Possibly due to new target boat resulting in more current?

Too much heat with Ta heat shields?

Bad News Bears 

 Friday, January 31, 2014, 11:28

Target container is coated with TaC.

The container is wrapped with 3 x Ta heat-shield.

Chamber was pumped down to 1.9e-7 Torr.

HS water valves were opened, no leak detected.

TGHT and TBHT were stepped up to 35A. Waited ~20min, current stabilized and vacuum starting to drop.

TGHT will be ramped up to 580A at 0.2A/min, max voltage = 11.05V.

TBHT will be ramped up to 230A at 0.2A/min, max volatge = 5V.

Initiating auto-ramping: Good Vac = 3.0e-5 Torr, Bad Vac = 4.0e-5 Torr.

 Monday, February 03, 2014, 10:21

TGHT reached 580A pver the weekend.

TBHT sitting at 1.4A, checked archive: never went over 1.6A. Aborted auto-ramp, re-starting auto ramp process for TBHT.

IGP1 = 1.6e-7 Torr.

 Monday, February 03, 2014, 15:23

TBHT running smoothly, must have been and electrical problem.

TBHT currently at 85A, vacuum has not changed, increasing TBHT auto-ramp to 2.0A/min

 Tuesday, February 04, 2014, 10:10

TBHT reached 230A yesterday pm. Measured temp this morning at 1800C.

Initiated TGHT/TBHT auto-cooling at 2.0A/min.

 Wednesday, February 05, 2014, 11:33

Chamber cooled down overnight, vented and opened up this morning.

Smooth run! Container fully sintered.

 Tuesday, February 11, 2014, 13:43

Target container is coated with TaC and wrapped with 3-Ta heat shields.

TGHT and TBHT will be ramped up to 820A and 300A, respectively.

Ramping rate set to 0.2A/min.

Good vac = 3e-5 Torr, Bad vac = 4e-5 Torr.

Chamber currently being pumped down...

 Tuesday, February 11, 2014, 16:33

Chamber pumped down to 2e-6 Torr.

HS cooling water valves opened; no leaks detected.

Will step up in the a.m.

 Wednesday, February 12, 2014, 11:41

IGP1 = 1.5e-7 Torr

TGHT max voltage = 17.05V, TBHT max voltage = 5V

Stepped TGHT and TBHT up to 35A

Waited 1hr15 before vacuum stabilized/ started to drop.

Initiating auto-ramping.

 Thursday, February 13, 2014, 10:19

TBHT and TGHT have both reached 300A

IGP1 = 2.4e-7 Torr.

Increasing TGHT auto-ramp to 2.0A/min

 Friday, February 14, 2014, 08:58

TGHT reached 820A yesterday afternoon. Measured internal temp this morning at 1300C.

Initiated TGHT auto-cooling at 2.0A/min and TBHT at 1.0A/min.

IGP1 = 3.2e-7 Torr.

 Monday, February 17, 2014, 12:02

Cooled down friday. Vented this morning.

Container fully sintered, smooth run!

 Tuesday, February 18, 2014, 12:12

A new target boat was sprayed with TaC coating and let dry.
The target boat is NOT wrapped with Ta-heat shield.

Thermocouples have been attached to the target boat in order to monitor the internal temperature of the new target boat design. 

The boat was installed in Evap#2, chamber is currently being pumped down.

 Tuesday, February 18, 2014, 14:20

Chamber was pumped down this morning to 2.9e-6 Torr. HS cooling water valves were opened, no leaks detected.

TGHT was stepped up to 35A, voltage max set at 14V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 700A.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

Temperature reading on left: thermocouple touching edge of target boat; temperature reading on right: thermocouple floating in center of target boat.

 Wednesday, February 19, 2014, 09:11

TGHT has been slowly ramping up overnight at a rate of 0.2A/min

IGP1 = 3.9e-7 Torr, TGHT = 260A; stepping ramping rate up to 2.0A/min

 Wednesday, February 19, 2014, 15:25

IGP1 = 9.4e-7 Torr

Thermocouple T2 = 1267.8C

Internal temp measured with Mikron = 1600C

Increasing max setpoint to 720A due to previous not fully sintered new design of target boat.

 Thursday, February 20, 2014, 09:17

Thermocouple T2 = 1254.5C

Internal temp measured with Mikron = 1811C

IGP1 = 2.6e-7 Torr

Reached max setpoint yesterday evening.

Initiating auto-cooling at 2.0A/min.

 Friday, February 21, 2014, 10:47

Vented and opened chamber this morning.

Target boat not fully sintered. [see attached photos]

Close to a full sinter, and will re-sinter next week with endcaps, so will not re-sinter by itself.

 Tuesday, February 25, 2014, 16:08

The target containers end-caps were coated with TaC spray and let dry.

The caps are inserted in the target boat vertically with no heat shield and no graphite foil. [see attached photo]

The chamber is currently being pumped down overnight.

 Wednesday, February 26, 2014, 09:54

Chamber was pumped down overnight to 4.2e-7 Torr.

HS cooling water valves opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 14V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 700A.

Will ramp up to 700A rather than the usual 580A due to last round of endcaps not fully sintering at 580A with new target boat design.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Thursday, February 27, 2014, 09:38

TGHT has been slowly ramping up overnight at a rate of 0.2A/min.

IGP1 = 2.8e-7 Torr; TGHT = 311A, 4.3V

Stepping ramping rate up to 2.0A/min.

 Friday, February 28, 2014, 08:53

TGHT reached max setpoint of 700A yesterday evening.

Internal temp measured with Mikron = 1700C

IGP1 = 3e-7 Torr 

Power = 12.95V

Initiating auto-cooling at 2.0A/min.

 Monday, March 03, 2014, 11:46

Vented and opened chamber this morning.

End caps not fully sintered! 

See attached photo comparison of fully sintered [grey], partially sintered from this round [light green] and pre-sinter [dark green].

Will not bother re-sintering, as partial sinter is enough.

 Friday, March 07, 2014, 11:41

The target container end-caps were sintered previously, but did not fully complete the sintering process [See elog entry # 119 EVAP2]

The caps are inserted in the target boat wrapped in graphite foils with 3 x Ta-heat shields.

The chamber was pumped down overnight.

IGP1 = 2e-7 Torr

HS cooling water valves were opened; no leaks detected.

TGHT was stepped up to 35A, voltage max set at 9.05V. TBHT currently at 0A.

 Friday, March 07, 2014, 11:52

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.5A/min and max setpoint to 500A.

Will ramp to 500A due to last failed round of end caps breaking with 3-ta heat shields at 580A.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Friday, March 07, 2014, 13:21

IGP1 = 8e-7 Torr.

TGHT = 72A

Vacuum stable; therefore, increasing ramping rate up to 1.0A/min

 Friday, March 07, 2014, 14:20

IGP1 = 9.8e-7 Torr

TGHT = 130A

Vacuum stable; therefore, increasing ramping rate up to 2.0A/min

John Wong wrote:

Friday, March 21, 2014, 16:09 Target container is loaded with 360 Discs of TiC.   Target length = 11.7cm.   Total green mass = 40.945g  Container is wrapped with 3 Ta-heat shields, and have been pumped down in the chamber.  For the sintering process:  TGHT ramp up to 820A, and TGHT to 300A at 0.1A/min.  Friday, March 21, 2014, 16:15 TGHT/TBHT were manually stepped up to 40A.   Vac stabilizes at 1.7e-6 Torr.   Initiate auto-ramping...

 Wednesday, March 26, 2014, 11:05

TBHT reached max desired current of 300A

IGP1 = 1.4e-6 Torr

TGHT = 543A

Increasing TGHT auto-ramp to 2.0A/min

 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

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

 Tuesday, June 17, 2014, 13:11

Target container is coated with TaC.

Container is wrapped with 3x Ta-heat shields.

Currently being pumped down.

For sintering process:

TGHT and TBHT will be ramped up to 820A and 300A respectively at 0.1A/min

 Tuesday, June 17, 2014, 14:22

HS water cooling valves opened, no leaks detected.

IGP1 @1.8e-6 Torr

TGHT max = 820A/ 17V

TBHT max = 300A/ 5V

Stepped up manually to 40A, waited ~20min, vacuum stable.

Initiating auto-ramp @ 1.0A/min

 Wednesday, June 18, 2014, 11:24

TGHT and TBHT reached their respective 820A and 300A last night.

Internal temp measured from side of EVAP2 with mikron = 1830C

IGP1 = 7.6e-7 Torr

Initiating auto-cool down process at 2.0A/min and 1.0A/min for TGHT and TBHT respectively

vented and opened this morning.

smooth run

 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

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

John Wong wrote:

Wednesday, July 23, 2014, 15:07 Target container is coated with TaC.  No Ta-heat shields are used. TGHT will be ramped up to 580A at 0.2A/min. TBHT will be ramped up to 230A at 0.2A/min. Chamber is currently being pumped down  Wednesday, July 23, 2014, 17:40 Vacuum came down to mid 10-6 Torr. Stepped up TGHT and TBHT to 30A - IG1 @ 1.4e-5 Torr. Initiated auto-ramping.  Thursday, July 24, 2014, 17:19 TGHT and TBHT have reached to 100A, and vacuum is coming down to 1.4e-6 Torr. Increase ramping rate, TGHT to 1A/min, TBHT 0.5A/min.  Friday, July 25, 2014, 11:26 Target container temperature reaches ~1550C at 580A on TGHT and 230A TBHT, and it has been heated for ~10 hrs. Auto-cooling initiated at 2A/min.

 Monday, July 28, 2014, 10:50

vented in air and opened this morning. successful run

 Monday, July 28, 2014, 14:41

Total number of foils: 445 discs

Total mass of materials [incl graphite foils]: 49.027 g

Total length packed: 11.2 cm

Container has no Ta heat shields.

Currently being pumped down.

Peter Kunz wrote:

Target was conditioned for 4 hours at 580A. Initiating ramp-down sequence @ 2A/min

 Tuesday, August 05, 2014, 12:00

target vented in air and taken out this morning

 Tuesday, August 05, 2014, 12:02

The target container end caps were coated with TaC spray and let dry.

The caps are inserted in the target boat vertically, wrapped in graphite foil with 3 x Ta-heat shield. [see attached photo]

The chamber is currently being pumped down.

John Wong wrote:

Laura Lambert wrote:  Tuesday, August 05, 2014, 12:02 The target container end caps were coated with TaC spray and let dry. The caps are inserted in the target boat vertically, wrapped in graphite foil with 3 x Ta-heat shield. [see attached photo] The chamber is currently being pumped down.    Tuesday, August 05, 2014, 17:19 HS water valve opened; no leaks detected.  Pressure @ 2.5e-6 Torr. Ramping up TGHT to 580A @ 1A/min.

 Thursday, August 07, 2014, 08:11

Yesterday the target boat was taken out.

The boat broke as it turns out it was used for a Niobium target and therefore wasn't coated with TaC.

The end caps were fully sintered.

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.

 Thursday, September 11, 2014, 13:14

The target container end caps were coated with TaC spray and let dry.

The caps are inserted in the target boat wrapped in graphite foil with 3 x Ta-heat shields.

The chamber is currently pumping down.

 Friday, September 12, 2014, 14:17

Chamber was pumped down overnight.

HS cooling water valves opened, no leaks detected.

IGP1 = 7.2e-7 Torr.

TGHT stepped up to 35A, TBHT at 0A.

Waited ~30min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min.

Will ramp TGHT to 580A with a max 10V.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

 Monday, September 15, 2014, 11:31

TGHT stopped at 500A due to not high enough voltage max.

Increased max voltage to 12V

 Monday, September 15, 2014, 14:17

IGP1 = 6.3e-7 Torr

Increasing ramping rate to 1.0A/min

 Tuesday, September 16, 2014, 09:04

TGHT reached 577A and finished auto-ramping, then proceeded to drop down to 560A overnight.

Increased max voltage to 13.05A and TGHT to 580A.

 Tuesday, September 16, 2014, 13:52

TGHT reached 580A and sat there for ~5hrs.

IGP1 = 6.1e-7 Torr.

Initiating auto-cool at 2.0A/min.

 Wednesday, September 17, 2014, 13:03

Vented in air.

Opened up....looked 'deceivingly' ok.

then i took a layer of Ta off....grrrr  

the 1st layer of Ta was holding the boat together. as soon as that layer was taken off the target boat broke.

see attached photos.