Laura Lambert wrote:

John Wong wrote:  Wednesday, January 15, 2014, 17:30 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.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)     Thursday, January 16, 2014, 11:35 Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed. TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop. Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.

 Friday, January 17, 2014, 09:28

TGHT/TBHT @ 300/200A.  TBHT voltage is limited at 3A.  

TGHT ramping rate increased to 2A/min.  Pressure @ 4.5e-7 Torr.  

John Wong wrote:

Wednesday, January 15, 2014, 17:30 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.  Tomorrow, the HS water valve can be opened to test for leaks.   Notes:  If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.   Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory)

 Thursday, January 16, 2014, 11:35

Chamber was pumped down overnight to 10-7 Torr. HS water valve was opened and no leak in vacuum was observed.

TGHT and TBHT were stepped up to 35A. Waited ~30min, current stabilized and vacuum starting to drop.

Initiating auto-ramping: Good Vac = 2.0e-5 Torr, Bad Vac = 3.0e-5 Torr.

 Wednesday, January 15, 2014, 17:30

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.  Tomorrow, the HS water valve can be opened to test for leaks.  

Notes: 

If everything is fine, TGHT/TBHT can be stepped up to 30A-50A.  Watch for the vacuum; once it's stable the auto ramping program can be initiated.  

Once TGHT/TBHT reached above 200A, the ramping rate for TGHT can be increased up to 2A/min.  (This step is to speed up the process; however it's not mandatory) 

See attached photo.

The Heat Shield has been taken to the Machine Shop for repair.

Friday, November 08, 2013

 The Heat Shield cooling line has been repaired and the lid re-installed in the evaporator. Photo attached.

Friday, November 08, 2013, 10:58 : Roughing Started

Friday, November 08, 2013, 11:05: Turbo started 

Friday, November 08, 2013, 11:15: Turbo at speed Vacuum at (IGP1) 5.7E-5 T 

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

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

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

Wednesday, November 06, 2013, 17:11

Step #1

Two samples: 

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

2.  A cross section of the tube.

Both samples are coated with the TaC matrix spray: 

0.05 moles TaC

0.005 moles of Mo2C, VC, Cr3C2, NbC 

A Rh foil is used as a protective under layer.

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

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

Samples will be heated up to 600A ~1800C

Chamber is currently being pumped down.

 Friday, November 08, 2013, 17:13

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

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

Monday, November 11, 2013, 08:10  

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

IGP2 currently at 3.5e-7 Torr.

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

 Step 2:

The coated tube is sintered with TaC-matrix.

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

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

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

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

 Friday, November 15, 2013, 11:04

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

 Monday, November 18, 2013, 17:22

Continue Step#2:

The sample looks ok after heating at 450A.

Re-heating it to 500A. 

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

Initiated auto-ramping...

With the help of Anthony Ip from vacuum group, the problem was diagnosed to be the roughing pump itself. The pump was replaced and pumping improved. The chamber can now be evacuated and turbo ready to start in less than 10 minutes.

The filter is not stocked by vacuum group and could not be replaced.

Last week parts of the roughing line was cleaned by Rick. The PVC roughing line has been replaced with a SST bellows. The SST bellows is KF25 and should be replaced by a KF40 bellows in the long run.

The source of the poor vacuum in the backing line seems to be related to a dirty filter. We will try to find a replacement filter next week.

The problem seem to have started September 17th, when backing preassure CG1A went from 40 mTorr to 130 mTorr. CG1B remained around 30 mTorr.

 Tuesday, October 29, 2013, 15:50: Pumping down

Wednesday, October 30, 2013, 09:32: Turbo started

Wednesday, October 30, 2013, 14:50: The Cu-bars were heated to 600A and 300A for TGHT and TBHT respectively.

Wednesday, October 30, 2013, 15:17: PS off. Turbo off.

Results can be found on DocuShare and in the attached plot.

Friday, October 04, 2013, 15:37

A LP target container is coated with TaC.  The container is wrapped with 3 layers to heat shield.  

This container will be used for the graphite tube test.  

Chamber is being pumped down.

 The HS cooling water valves are open and no leaks are detected. 

TGHT will be ramped up to 580A at 0.2A/min

TBHT will be ramped up to 230A at 0.2A/min.

The temperature will be monitored and measured. 

 Sunday, October 06, 2013, 19:55

Tuesday, October 22, 2013, 16:49

The target was heated up to 580A and the temperature inside the tube was measured to be ~1800C and the outside surface was ~1400C.

The target was cooled down.  Then the graphite tube was inserted.

There are two thermcouples inserted inside the tube on both ends.

Chamber has been pumped down to 4.33 e-7 Torr.  No leaks were detected.

Target will be heated up again to TGHT @ 580A / TBHT @ 230A at 0.2A/min.

The temperatures will be monitored.

T1 = left (floating)

T2 = right (toughing C-grv tube)

(wtf ionizer pointing into the page).

 Thursday, October 24, 2013, 16:35

TGHT/TBHT reached to 580A/230A. 

T1 = 1642C

T2 = Error?? Reading goes on/off intermittently, showing 900 - 1900C

Thursday, October 24, 2013, 16:45 

Ramping up TGHT to 680A to see if T1 can reach 1700C.

IG1 currently at 5.2e-7 Torr.

 Friday, October 25, 2013, 12:30

TGHT was ramped up to 632A (stopped due to voltage limiting). 

T1 was measured at 1960C.  Vac went up as it was heated up.  (see attachment #2)

Target was cooled down at 5A/min, now at 0A.

The chamber will be vented and the target will be inspected.

This run is complete.

Thursday, September 26, 2013, 13:04

The LP-IG-LIS target container is coated with TaC. 

Container is wrapped with 3 layers of Ta heat shield and about to go through the sintering process.

A thermocouple is inserted to measure the temperature inside the tube (1st attempt ever). 

Click on the link for detailed pictures:

https://www.dropbox.com/sh/6dc5arajg87mws9/6cU5OxjkZg

TGHT will be ramped up to 580A at 0.2A/min

TBHT will be ramped up to 230A at 0.2A/min.

Chamber has been pumped down.  HS cooling H2O valves are opened, and no leaks are detected. 

Currently IGP1 @ 5.9e-6 Torr.

 Thursday, September 26, 2013, 15:44

TGHT stepped up to 30A.  TBHT currently @ 0A. 

Temp @ 35C, Vac @ 1.4e-5 Torr.

 Monday, September 30, 2013, 14:54

The container was heated up to 580A TGHT/ 230A TBHT for a day (see attachment #1 for vac vs cur plot).

The temperature was measure at ~1780C. (see link for details: https://www.dropbox.com/sh/d8d9j2t60qlm3jk/nkMh7dx_R8 )

The target was cooled down and vented. 

Proceed complete.

John Wong wrote:

John Wong wrote: Tuesday, September 17, 2013, 11:14 Target boat contains 5 Nb discs.  3 discs are wraps with 0.001" thin of Nb foil (99.8% pure), and 2 are wraps with 0.001" Ta foil (see attachment#1) Chamber has been pumped down over night.  Pressure is currently at 9.8e-7 Torr.  Heating instructions: Samples will be heated up to 800C.  TGHT will be ramped up accordingly. (Two thermocouples are wielded on the target container.) Once at the desired temperature; the samples will be heat for 4 hours before cooling down.  Tuesday, September 17, 2013, 14:37 Target temperature has reached to 800C at around 13:00 (see attachment#2) TGHT @ 230A/3.07V (local 233A/3.25V).  IG @ 1.06e-6 Torr.  The heater will be ramped down at ~17:00 at 2A/min.  Tuesday, September 17, 2013, 17:36 Target temp: T1 = 805C, T2=797.6C IG @ 9.4e-7 Torr. Cooling down initiated.   Wednesday, September 18, 2013, 11:34 TGHT at 0A.  Temp at 22C.  IG @ 5.8e-7 Torr. Venting chamber.    Friday, September 20, 2013, 14:56 Target contains batch#3 sample wrapped with Nb foil.  Chamber has been pumped down to 1.03e-6 Torr.  Samples will be heated up to 1200C for 4 hours.    Friday, September 20, 2013, 16:54 TGHT at 450A, temp stabilizes at 1238C. Will cool down at 20:30 tonight. Friday, September 20, 2013, 20:40   Samples has been heated for 4 hours at 1235C.   Cooling down initiated.   Monday, September 23, 2013, 14:40 Chamber was vented. Batch#3 process completed.

 Monday, September 23, 2013, 16:14

Batch#4.  Target container contains 2 Nb stables (a bullet type and a disc).  

Samples are wrapped with "dimpled" Nb foil to prevent diffusion bonding. 

Chamber has been pumped down to 8.3e-7 Torr, CG1B @ 30mT, CG1A @ 118mT. 

Samples will be heated up to 1400C for 4 hours. 

Monday, September 23, 2013, 17:46

TGHT at 620A. Temp at 1400C. Current pressure @ 2.5e-6 Torr. 

Tuesday, September 24, 2013, 16:45

Sample#4 was heated up to 1400C and after about 3hrs, the target container started to break.

See the link below for more details:

https://www.dropbox.com/s/9mhpkz66u6yqldm/Nb_1400C.mp4

John Wong wrote:

Tuesday, September 17, 2013, 11:14 Target boat contains 5 Nb discs.  3 discs are wraps with 0.001" thin of Nb foil (99.8% pure), and 2 are wraps with 0.001" Ta foil (see attachment#1) Chamber has been pumped down over night.  Pressure is currently at 9.8e-7 Torr.  Heating instructions: Samples will be heated up to 800C.  TGHT will be ramped up accordingly. (Two thermocouples are wielded on the target container.) Once at the desired temperature; the samples will be heat for 4 hours before cooling down.  Tuesday, September 17, 2013, 14:37 Target temperature has reached to 800C at around 13:00 (see attachment#2) TGHT @ 230A/3.07V (local 233A/3.25V).  IG @ 1.06e-6 Torr.  The heater will be ramped down at ~17:00 at 2A/min.  Tuesday, September 17, 2013, 17:36 Target temp: T1 = 805C, T2=797.6C IG @ 9.4e-7 Torr. Cooling down initiated.   Wednesday, September 18, 2013, 11:34 TGHT at 0A.  Temp at 22C.  IG @ 5.8e-7 Torr. Venting chamber.

 Friday, September 20, 2013, 14:56

Target contains batch#3 sample wrapped with Nb foil. 

Chamber has been pumped down to 1.03e-6 Torr. 

Samples will be heated up to 1200C for 4 hours.  

 Friday, September 20, 2013, 16:54

TGHT at 450A, temp stabilizes at 1238C.

Will cool down at 20:30 tonight.

Friday, September 20, 2013, 20:40  

Samples has been heated for 4 hours at 1235C.  

Cooling down initiated. 

 Monday, September 23, 2013, 14:40

Chamber was vented.

Batch#3 process completed.

Laura Lambert wrote:

John Wong wrote: Tuesday, September 17, 2013, 11:14 Target boat contains 5 Nb discs.  3 discs are wraps with 0.001" thin of Nb foil (99.8% pure), and 2 are wraps with 0.001" Ta foil (see attachment#1) Chamber has been pumped down over night.  Pressure is currently at 9.8e-7 Torr.  Heating instructions: Samples will be heated up to 800C.  TGHT will be ramped up accordingly. (Two thermocouples are wielded on the target container.) Once at the desired temperature; the samples will be heat for 4 hours before cooling down.  Tuesday, September 17, 2013, 14:37 Target temperature has reached to 800C at around 13:00 (see attachment#2) TGHT @ 230A/3.07V (local 233A/3.25V).  IG @ 1.06e-6 Torr.  The heater will be ramped down at ~17:00 at 2A/min.  Tuesday, September 17, 2013, 17:36 Target temp: T1 = 805C, T2=797.6C IG @ 9.4e-7 Torr. Cooling down initiated.   Wednesday, September 18, 2013, 11:34 TGHT at 0A.  Temp at 22C.  IG @ 5.8e-7 Torr. Venting chamber.    Thursday, September 19, 2013, 11:41 Target boat contains batch#2 Nb samples (see attachment #1) Chamber has been pumped down over night.   IG @ 5.5e-07 Torr.  CG1B @ 0.033 T CG1A @ 0.127 T There is a leak in the backing line.  BV1 was bypassed in order to turn on the turbo pump. (Will investigate the leaks after the processes are done)   *See attached picture to view samples

Thursday, September 19, 2013, 17:01  

TGHT reached to 800A.  Temp at 795.9C for 4 hours.  Vac at 5.8e-7 Torr.

Cooling down initiated.  ramping rate at 2A/min. 

John Wong wrote:

Tuesday, September 17, 2013, 11:14 Target boat contains 5 Nb discs.  3 discs are wraps with 0.001" thin of Nb foil (99.8% pure), and 2 are wraps with 0.001" Ta foil (see attachment#1) Chamber has been pumped down over night.  Pressure is currently at 9.8e-7 Torr.  Heating instructions: Samples will be heated up to 800C.  TGHT will be ramped up accordingly. (Two thermocouples are wielded on the target container.) Once at the desired temperature; the samples will be heat for 4 hours before cooling down.  Tuesday, September 17, 2013, 14:37 Target temperature has reached to 800C at around 13:00 (see attachment#2) TGHT @ 230A/3.07V (local 233A/3.25V).  IG @ 1.06e-6 Torr.  The heater will be ramped down at ~17:00 at 2A/min.  Tuesday, September 17, 2013, 17:36 Target temp: T1 = 805C, T2=797.6C IG @ 9.4e-7 Torr. Cooling down initiated.   Wednesday, September 18, 2013, 11:34 TGHT at 0A.  Temp at 22C.  IG @ 5.8e-7 Torr. Venting chamber.

 Thursday, September 19, 2013, 11:41

Target boat contains batch#2 Nb samples (see attachment #1)

Chamber has been pumped down over night.  

IG @ 5.5e-07 Torr. 

CG1B @ 0.033 T

CG1A @ 0.127 T

There is a leak in the backing line.  BV1 was bypassed in order to turn on the turbo pump. (Will investigate the leaks after the processes are done)  

*See attached picture to view samples

Tuesday, September 17, 2013, 11:14

Target boat contains 5 Nb discs.  3 discs are wraps with 0.001" thin of Nb foil (99.8% pure), and 2 are wraps with 0.001" Ta foil (see attachment#1)

Chamber has been pumped down over night.  Pressure is currently at 9.8e-7 Torr. 

Heating instructions:

Samples will be heated up to 800C.  TGHT will be ramped up accordingly. (Two thermocouples are wielded on the target container.)

Once at the desired temperature; the samples will be heat for 4 hours before cooling down.

 Tuesday, September 17, 2013, 14:37

Target temperature has reached to 800C at around 13:00 (see attachment#2)

TGHT @ 230A/3.07V (local 233A/3.25V). 

IG @ 1.06e-6 Torr. 

The heater will be ramped down at ~17:00 at 2A/min.

 Tuesday, September 17, 2013, 17:36

Target temp: T1 = 805C, T2=797.6C

IG @ 9.4e-7 Torr.

Cooling down initiated. 

 Wednesday, September 18, 2013, 11:34

TGHT at 0A.  Temp at 22C. 

IG @ 5.8e-7 Torr.

Venting chamber.

John Wong wrote:

Tuesday, August 27, 2013, 16:48 Target boat is filled with TaC coated endcaps (brown) and some partial sinterred ones (gray) from before.  (see attachment#1). The container is wrapped with Ta heat-shield. Chamber has been pumped down; IG currently @ 7.3e-7 Torr.  Heat-shield cooling water valves are open; no leaks are detected. Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.  Wednesday, August 28, 2013, 16:09 TGHT has reached to 580A and been heated for over 4 hours. IG is coming down, currently at 1.9 e-6 Torr. Initiated auto-cooling.  2A/min.

 Thursday, August 29, 2013, 11:50

TGHT at 0 A

IG at 3.5e-7 Torr

Turning off EVAP2 and venting chamber

Process complete

Tuesday, August 27, 2013, 16:48

Target boat is filled with TaC coated endcaps (brown) and some partial sinterred ones (gray) from before.  (see attachment#1).

The container is wrapped with Ta heat-shield.

Chamber has been pumped down; IG currently @ 7.3e-7 Torr. 

Heat-shield cooling water valves are open; no leaks are detected.

Initiated TGHT auto-ramping at 0.5A/min, set TGHT max at 580A.

 Wednesday, August 28, 2013, 16:09

TGHT has reached to 580A and been heated for over 4 hours.

IG is coming down, currently at 1.9 e-6 Torr.

Initiated auto-cooling.  2A/min. 

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.

Laura Lambert wrote:

Thursday, August 08, 2013, 15:19 NiO target materials loaded into the container yesterday. Total discs = 530, (5 discs/pack) length [after loaded] = 9.0cm Target container is wrapped with Ta-heat shields, and will be removed after sintering process. No end caps were inserted. The chamber has been pumped down and currently IG1 = 3.8x10-06 Torr. The HS cooling water was turned on and no leaks were detected. TGHT and TBHT have been stepped up to 50A. Auto-ramping setting: 0.2A/min for TGHT max = 250A, TBHT max = 230A. Good vacuum = 3.00e-05 Torr Bad vacuum = 4.00e-05 Torr **See attachment #1 for pictures of target pre-sintering

 Thursday, August 08, 2013, 17:26

Pressure is stabilizing at ~2.2e-5 Torr.  TGHT/TBHT at 50A.

Initiated auto-ramping... 

Sunday, August 11, 2013, 21:30  

TGHT/TBHT have reached to 250A/230A.  Target have been heated over the weekend.  

Cooling down initiated; 2A/min.  

The chamber wil be vented in air tomorrow. 

 Monday, August 12, 2013, 18:01

The sinterring process is complete. 

The target is ready to be removed from the evaporator, and the endcaps will be inserted.

Thursday, August 08, 2013, 15:19

NiO target materials loaded into the container yesterday.

Total discs = 530, (5 discs/pack)

length [after loaded] = 9.0cm

Target container is wrapped with Ta-heat shields, and will be removed after sintering process.

No end caps were inserted.

The chamber has been pumped down and currently IG1 = 3.8x10-06 Torr.

The HS cooling water was turned on and no leaks were detected.

TGHT and TBHT have been stepped up to 50A.

Auto-ramping setting:

0.2A/min for TGHT max = 250A, TBHT max = 230A.

Good vacuum = 3.00e-05 Torr

Bad vacuum = 4.00e-05 Torr

**See attachment #1 for pictures of target pre-sintering