Ta#67 Thin foil LP-SIS target description: 

Total Ta foils = 470 loaded into 2 packs of 235 foils each.

Foil Thickness = 0.010mm (0.0004") avg Measured. 

Target material batch:  https://elog.triumf.ca/TIS/Target+Production/143

Target density = 4.498 g/cm3

Target length = 3.7465 cm

Total Mass = 16.8509 g [Incl foils + Ta wire on 2 packs]

Total mass w/ Target oven =  415g (No end caps)

Discs in target are arranged as follows: 2packs

Dimpling direction on foils/ Packs.                                                               --> Center <--

No Ta foil heat shield added

Monday, July 22, 2024, 14:53: Roughing. 

Halt roughing. Install heat plates.

Monday, July 22, 2024, 15:06: Roughing.

Monday, July 22, 2024, 15:26: TP On.

Monday, July 22, 2024, 15:34: TP Timeout. Restart. 

Monday, July 22, 2024, 15:35: TP at speed (Green) 

Monday, July 22, 2024, 15:36: PS On. TGHT / TBHT to 5/5 A manually. OK. Tap down. 

Tuesday, July 23, 2024, 07:03: Auto-ramping TGHT / TBHT to 120 / 60 A @ 2 A per min. Desired temperature 1900 C.

Tuesday, July 23, 2024, 08:02: OMEGA IR2C Laser off. Slope set to 0.98. 

Tuesday, July 23, 2024, 08:06: Auto-ramping TGHT / TBHT to 300 / 150 A @ 2 A per min. 

Tuesday, July 23, 2024, 09:57: Auto-ramping TGHT / TBHT to 500 / 200 A @ 2 A per min. Temperature @ 1022 C. 

Tuesday, July 23, 2024, 11:59: Auto-ramping TGHT / TBHT to 580 / 230 A @ 2 A per min. Temperature @ 1538 C.

Tuesday, July 23, 2024, 12:46: TGHT / TBHT @ 580 / 230 A (569 / 233 A). Temperature @ 1710 C. Vacuum @ 7.44e-06T. 

Tuesday, July 23, 2024, 14:23: TGHT / TBHT @ 580 / 230 A (568 / 233 A). Auto-ramping TGHT to 620 A @ 2 A per min. Temperature @ 1721 C. Vacuum @ 5.06e-06T. 

Tuesday, July 23, 2024, 14:48: TGHT / TBHT @ 620 / 230 A 609 / 233 A). Auto-ramping TGHT to 630 A @ 2 A per min. Temperature @ 1799 C. Vacuum @ 6.76e-06T.  

Tuesday, July 23, 2024, 14:56:  TGHT / TBHT @ 630 / 230 A 618 / 233 A). Temperature @ 1816 C. Vacuum @ 7.14e-06T. Tapping up manually TGHT to get to 1900degC 

Tuesday, July 23, 2024, 15:23:  TGHT / TBHT @ 670 / 230 A 657 / 233 A).  Temperature @ 1890 C. Vacuum @ 9.94e-06T.  Stopping and waiting for 5min.

Tuesday, July 23, 2024, 15:39: Target ramp down 2A/min to 0 both TGHT and TBHT. 

Wednesday, July 24, 2024, 08:50: TP off.

Wednesday, July 24, 2024, 09:18: Venting.

Wednesday, July 24, 2024, 10:28: Target removed. EVAP2 clear. 

Friday, August 30, 2024, 11:31

The coated container was wrapped in 4 Ta foil heatshields.

Vacuum IGP1 initial =3.1 e-07 Torr

Target temperature on OMEGA= 1850-1900 C

OMEGA slope:= 0.990

Target time at max temperature = 4 hours

Final Current TBHT= 230 A

Final TGHT current= ~400A (adjustable)

Heating autoramp starged at 1A/min on  TGHT  100A and TBHT

Then at 1A/min  to =400 A TGHT and 230A TBHT

Good vacuum = 5.0 e-04 Torr

Bad vacuum = 5.0E-02 Torr

note: Left TBHT hole is off from center by a good margin

Sunday, September 01, 2024, 07:32

Starting initial ramp at 1A/min to 50A

Sunday, September 01, 2024, 15:20

have ramped ;up at 1A/min on both TGHT and TBHT but had two issues.

1) Set current and readback current have discrepancies but the TBHT discrepancy is significant (TBHT Set at 188 while RD is 231.9 A @ 1.9V)

   TGHT also has odd behavior with set point 405 giving 392A RD and 0.067V.  Will hold until 430pm before starting ramp down

Sunday, September 01, 2024, 16:30

Started rampdown at -2A/min TGHT and -1A/min TBHT

Note: OMEGA not able to give any reasonable readings

Tuesday, September 03, 2024, 13:51

After troubleshooting EVAP2 it was found that a copper line was touching the metal encasement grid most likely resulting in a short.  A short was seeing and it disappeared after moving the copper line away from the grid.  

Upon restarting on epics the PS went to maximum current and it was shut off after 30seconds to a minute.  The system was checked again by Arthur and TGHT was manually increased to 5A and then set to Zero again.  Arthur thinks that the PS probably requires this step after switching from local controls to remote.  Will start the sintering again as the container is coated but not sintered.

Tuesday, September 03, 2024, 14:03

ramping at 1A/min on both TGHT and TBHT to 90A. 

Tuesday, September 03, 2024, 22:25  

Started rampdown at -2A/min TGHT and -1A/min TBHT.  HIgh temperature from OMEGA was 1825 C at 430A readback on TGHT. 

Tuesday, May 15, 2012, 12:24

The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1. 

This target is going into Evap#2 for re-conditioning.  It is currently being pumped down. 

John Wong wrote:

Tuesday, May 15, 2012, 12:24 The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1.  This target is going into Evap#2 for re-conditioning.  It is currently being pumped down.

Friday, May 18, 2012, 12:19 

The target is wrapped with only one heat shield.

Evaporator #2 Target Heater is now auto-ramping at 0.5 A/min, up to 820 A, with the maximum voltage limited at 2 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum). Tube Heater is auto-ramping at 0.5 A/min, up to 230 A, with the maximum voltage limited at 1 V. See attachments.

Nikita Bernier wrote:

John Wong wrote: Tuesday, May 15, 2012, 12:24 The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1.  This target is going into Evap#2 for re-conditioning.  It is currently being pumped down.    Friday, May 18, 2012, 12:19  The target is wrapped with only one heat shield. Evaporator #2 Target Heater is now auto-ramping at 0.5 A/min, up to 820 A, with the maximum voltage limited at 2 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum). Tube Heater is auto-ramping at 0.5 A/min, up to 230 A, with the maximum voltage limited at 1 V. See attachments.

 Friday, May 18, 2012, 13:15

Increased TBHT voltage to 5V, and TGHT to 15V.  Currently, TBHT =83A, 0.986V, TGHT= 144A, 1.65V, IGP1 = 5.2e-7 Torr, IGP2 = 4.3e-7 Torr. 

Continue ramping up... 

 Tuesday, May 22, 2012, 12:02

TGHT and TBHT were ramped up to 830A/13.65V (local), and 235A/3.85V, respectively.  The target was conditioned over the long weekend.  

John Wong wrote:

Nikita Bernier wrote: John Wong wrote: Tuesday, May 15, 2012, 12:24 The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1.  This target is going into Evap#2 for re-conditioning.  It is currently being pumped down.    Friday, May 18, 2012, 12:19  The target is wrapped with only one heat shield. Evaporator #2 Target Heater is now auto-ramping at 0.5 A/min, up to 820 A, with the maximum voltage limited at 2 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum). Tube Heater is auto-ramping at 0.5 A/min, up to 230 A, with the maximum voltage limited at 1 V. See attachments.  Friday, May 18, 2012, 13:15 Increased TBHT voltage to 5V, and TGHT to 15V.  Currently, TBHT =83A, 0.986V, TGHT= 144A, 1.65V, IGP1 = 5.2e-7 Torr, IGP2 = 4.3e-7 Torr.  Continue ramping up...   Tuesday, May 22, 2012, 12:02 TGHT and TBHT were ramped up to 830A/13.65V (local), and 235A/3.85V, respectively.  The target was conditioned over the long weekend.

 Tuesday, May 22, 2012, 12:13

Initiating the cool-down process at 5 A/min.

See archive plots of the Target Heater (Attachment 1) and the Tube Heater (Attachment 2).

Nikita Bernier wrote:

John Wong wrote: Nikita Bernier wrote: John Wong wrote: Tuesday, May 15, 2012, 12:24 The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1.  This target is going into Evap#2 for re-conditioning.  It is currently being pumped down.    Friday, May 18, 2012, 12:19  The target is wrapped with only one heat shield. Evaporator #2 Target Heater is now auto-ramping at 0.5 A/min, up to 820 A, with the maximum voltage limited at 2 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum). Tube Heater is auto-ramping at 0.5 A/min, up to 230 A, with the maximum voltage limited at 1 V. See attachments.  Friday, May 18, 2012, 13:15 Increased TBHT voltage to 5V, and TGHT to 15V.  Currently, TBHT =83A, 0.986V, TGHT= 144A, 1.65V, IGP1 = 5.2e-7 Torr, IGP2 = 4.3e-7 Torr.  Continue ramping up...   Tuesday, May 22, 2012, 12:02 TGHT and TBHT were ramped up to 830A/13.65V (local), and 235A/3.85V, respectively.  The target was conditioned over the long weekend.      Tuesday, May 22, 2012, 12:13 Initiating the cool-down process at 5 A/min. See archive plots of the Target Heater (Attachment 1) and the Tube Heater (Attachment 2).

 Tuesday, May 22, 2012, 15:24

TGHT/TBHT were ramped down to 0A.  The target has cooled for about 45 min.  All pumps and chillers are off.  The chamber has been vented.

John Wong wrote:

Nikita Bernier wrote: John Wong wrote: Nikita Bernier wrote: John Wong wrote: Tuesday, May 15, 2012, 12:24 The HP-SIS SiC target was made on Nov 03, 2010.  The target consists of 405 discs, 18.5cm in length.  It was sintered in the Evaporator#1.  This target is going into Evap#2 for re-conditioning.  It is currently being pumped down.    Friday, May 18, 2012, 12:19  The target is wrapped with only one heat shield. Evaporator #2 Target Heater is now auto-ramping at 0.5 A/min, up to 820 A, with the maximum voltage limited at 2 V, between 2.00e-05 (Good vacuum) and 3.00e-05 Torr (Bad vacuum). Tube Heater is auto-ramping at 0.5 A/min, up to 230 A, with the maximum voltage limited at 1 V. See attachments.  Friday, May 18, 2012, 13:15 Increased TBHT voltage to 5V, and TGHT to 15V.  Currently, TBHT =83A, 0.986V, TGHT= 144A, 1.65V, IGP1 = 5.2e-7 Torr, IGP2 = 4.3e-7 Torr.  Continue ramping up...   Tuesday, May 22, 2012, 12:02 TGHT and TBHT were ramped up to 830A/13.65V (local), and 235A/3.85V, respectively.  The target was conditioned over the long weekend.      Tuesday, May 22, 2012, 12:13 Initiating the cool-down process at 5 A/min. See archive plots of the Target Heater (Attachment 1) and the Tube Heater (Attachment 2).  Tuesday, May 22, 2012, 15:24 TGHT/TBHT were ramped down to 0A.  The target has cooled for about 45 min.  All pumps and chillers are off.  The chamber has been vented.

 Monday, June 11, 2012, 12:20

After the re-conditioning, the target's end-caps vaporized.  This is something happened before (see elog entries below):

https://elog.triumf.ca/TIS/Evaporator_1/20

https://elog.triumf.ca/TIS/Evaporator_1/22

The caps were removed and yellow crystals were observed. (see attachment#1).

The D-caps will be inserted in both ends and will be re-conditioned again to see if the yellow crystals can be removed at high temperature.

Tuesday, August 14, 2012, 15:44

This SiC target was prepared in May 2011 with the Evaporator#1.  The target will not used for online. 

Two endcaps were inserted with the new expansion tool.  The target will be heated up to the normal operating condition (TGHT =580A, TBHT = 230A). 

The chamber is currently being pumped down. 

 Tuesday, August 14, 2012, 16:21

Earlier, the Cu-heat shield was removed from the evaporator to replace the insulators, so all the seals were placed with new ones.  However,

there seems to be some leaks after the HS cooling water is turned on.  (see attachment#1).

The TP off, and the chamber is vented for investigation.

 Tuesday, August 14, 2012, 17:25

All the 3 seals for the Cu-heat shield were replaced.  The chamber has been pumped down and the HS water valve is open.  No leaks are detected.

Tuesday, August 14, 2012, 17:29

Initiated auto-ramping at 2A/min for both TGHT and TBHT.

Parameter constraints: good vac @ 2.0e-5 Torr, bad vac @ 3.0e-5 Torr.

Currently, IG1 @ 6.5e-6 Torr.

 Wednesday, August 15, 2012, 09:52

TGHT and TBHT have reached to 520A and 230A, respectively, and have stayed at the currents for about 10 hours. (see attachment #2) 

IG is currently at 7.7e-7 Torr.  

Initiating auto-cool down at 2A/min. 

 Thursday, August 16, 2012, 11:23

Chamber is vented.

Friday, February 22, 2013, 15:49

The LP-SIS RFQ target container was previously coated with TaC and sintered up to ~1500C (TGHT @ 600A, TBHT @ 300A). 

The container is loaded with 325 discs of SiC, a total of 10.9cm in length. 

For this process,

TGHT will be ramped up to 600A and at the same time TBHT will go up to 300A.  No Ta-heat shield is used. 

The ramping rate is set to 0.2A/min.

The chamber is currently being pumped down. 

 Friday, March 01, 2013, 15:57

The target was further heated up to 650A TGHT and 300A TBHT for 4 hours yesterday; then it was cooled down.  

Some reactions on the target end (where the D-cap inserted) was observed.  

Yellow crystals on the D-cap was formed, just as we have seen before.  

Overall, the target looks good!  

See attachment#2 for the target production. 

More about the gasses analyst from the RGA later...  

Monday, June 17, 2013, 16:57

Target is loaded with 510 SiC discs

Container was previously coated with TaC and sintered

SiC is wrapped with tantalum heat shield

Chamber is currently being pumped down

Laura Lambert wrote:

Monday, June 17, 2013, 16:57 Target is loaded with 510 SiC discs Container was previously coated with TaC and sintered SiC is wrapped with tantalum heat shield Chamber is currently being pumped down

 Tuesday, June 18, 2013, 16:16

HS water valves opened; no leaks were detected.

IG @ 8.9e-7 Torr.

Note: This target has a regular end cap inserted on one end, and the other with a D-cap. 

TGHT will be heated up to 820A and TBHT to 300A; ramping rate at 1A/min.

Stepped up TGHT/TBHT to 60A.  Vacuum slowly increasing... 

 Tuesday, June 18, 2013, 17:55

Stepped up TGHT/TBTH to 80A.  10 mins later, pressure went beyond the limit and tripped of the p/s.  F!

Allowed vacuum to come down below 8e-5 Torr.  Stepped down TGHT/TBHT to 50A.

Currently IG @ 4.8-5 Torr. 

Initiated auto-ramping:  setting: Good Vac = 3e-5 Torr, Bad Vac = 4.0e-5 Torr. 

 Thursday, June 20, 2013, 06:21

About 10 min ago, Evap tripped off due to high vacuum. 

Vacuum came back down below the trip limit and both TGHT/TBHT p/s were stepped down to 40A and turned back on.

Changed auto ramping rate to 05A/120min.  

The process continues...  (And I'm going back to sleep!) 

 Friday, June 21, 2013, 15:19

Vacuum is close to the trip limit. 

Change the ramping rate to 0.2A/120min. 

 Monday, June 24, 2013, 17:04

Organic burnt out is complete and vacuum has come down to ~9.0e-6 Torr.

Increase ramping rate to 0.2A/60min - The sintering process should take about another 2 days if everything goes smoothly. 

 Wednesday, June 26, 2013, 17:29

TGHT & TBHT have reached to 820A and 300A, respectively, for 4 hours.

Vacuum is at 9e-7 Torr. 

Cooling down is in progress, at a rate of 1.0A/min for TGHT and 0.5A/min for TBHT.

The target will be ready to come out by tomorrow.

 Thursday, June 27, 2013, 11:02

TGHT/TBHT reached to 0A.  Vacuum is leveled at 1.2e-7 Torr. 

Chamber will be vented in air soon.

 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.  

 Thursday, October 23, 2014, 15:34

*See elog #142 for target description*

one endcap still in place, one removed for OMEGA-IR2C beam to reach material [see pic]

no heat shields

currently being pumped down

 Friday, October 24, 2014, 11:34

EVAP2 pumped down overnight.

IGP1 = 7e-7 Torr

HS water valves opened, no leaks detected.

TGHT will be ramped up to 1400C

TBHT will be ramped up to 230A

 Friday, October 24, 2014, 14:32

TBHT reached 230A, TGHT reached 1400C

Stepped TGHT up manually to 1600C; TGHT = 693A, 10.6V [see pic]

 Friday, October 24, 2014, 15:58

TGHT = 760A, 12.07V [local read back] = setpoint.

epics readback TGHT = 754.8A, 11.76V

OMEGA = 1700C

Friday, October 24, 2014, 16:26

OMEGA = 1800C

epics readback TGHT = 828.7A, 13.15V

Friday, October 24, 2014, 16:34

OMEGA = 1900C

epics readback TGHT = 899A, 14.53V

Friday, October 24, 2014, 16:46

OMEGA = 2000C

epics readback TGHT = 967A, 15.8V

MIKRON target spot on SiC = 1650C, e = 0.97

Tuesday, November 04, 2014, 16:08

The purpose of this experiment is to improve the fabrication of SiC.  Previously, the SiC target was heated to 2000c and yellow crystals were observed.

In this experiment, 10g of SiC powder (7um size) was previously milled down (actual size to be determined under SEM).  The powder was mixed with 5% PVA and the slurry was pour onto a glass and let dry.  The semi-dry slurry was rolled up into balls. The SiC balls were let dry in over (115C) over night. Taken out 2.903g SiC + 5% PVA, it's rolled up with a small sheet of graphite foil.  Then the targer boat is filled with the sample and wrapped with 3-layers of Ta-heat shield.

The sample will be heated up to 2000C to see if the yellow crystals are reproducible.  It is suspected that there might be a phase transformation from 6H alpha-SiC to 3C beta-SiC. 

Chamber is currently being pumped down... 

Wednesday, November 05, 2014, 14:04

TGHT was ramped up over night, currently at 485A = 1800 C. 

Will do manual step up to get to 2000C. 

Laura Lambert wrote:

Thursday, October 23, 2014, 15:34 *See elog #142 for target description* one endcap still in place, one removed for OMEGA-IR2C beam to reach material [see pic] no heat shields currently being pumped down  Friday, October 24, 2014, 11:34 EVAP2 pumped down overnight. IGP1 = 7e-7 Torr HS water valves opened, no leaks detected. TGHT will be ramped up to 1400C TBHT will be ramped up to 230A  Friday, October 24, 2014, 14:32 TBHT reached 230A, TGHT reached 1400C Stepped TGHT up manually to 1600C; TGHT = 693A, 10.6V [see pic]  Friday, October 24, 2014, 15:58 TGHT = 760A, 12.07V [local read back] = setpoint. epics readback TGHT = 754.8A, 11.76V OMEGA = 1700C Friday, October 24, 2014, 16:26 OMEGA = 1800C epics readback TGHT = 828.7A, 13.15V Friday, October 24, 2014, 16:34 OMEGA = 1900C epics readback TGHT = 899A, 14.53V Friday, October 24, 2014, 16:46 OMEGA = 2000C epics readback TGHT = 967A, 15.8V MIKRON target spot on SiC = 1650C, e = 0.97

 Tuesday, November 04, 2014, 15:59

Target was heated up to 2000C and last for about 1.5 days before the right leg (ionizer points into the page) broke off. 

Interesting discovery...  The "yellowish" crystals are forming on the discs. 

Suspecting a phase transformation of 6H (hexagonal/- alpha SiC (hexagonal) polytype to 3C(cubic) - beta SiC

More study needs to be done... 

See elog # 168.

The leg of this target was repaired in the Machine shop. 

THIS TARGET WILL NOT BE USED ONLINE -  IT WILL BE USED FOR OFFLINE R&D PURPOSES.

 Friday, April 17, 2015, 16:01

Total number of foils: 520 discs

Total mass of materials [incl graphite foils]: 60.2441g

Total length packed: 17.0cm

Container is wrapped with 3x Ta-heat shields.

No endcaps inserted to allow outgasing.

Currently being pumped down.

 Monday, April 20, 2015, 11:08

Target container is coated with TaC and wrapped with 3-Ta heat shields, not incl center block.

TGHT and TBHT will be ramped up to 820A and 230A, respectively.

Chamber pumped down over the weekend.

IGP1 = 2.1e-7 Torr.

HS cooling water valves opened; no leaks detected.

TGHT max voltage = 18V, TBHT max voltage = 5V

....

attempted to start stepping up manually.

power supply not responding to epics controls for TBHT only...looking into problems now...

 Monday, April 20, 2015, 16:06

Epics is working.

Power supply connections unplugged/plugged back in.

Everything working again.

Tapped up manually to 40A.

Waited ~1hr30 for vacuum to stabilize.

IGP1 = 1.8e-6 Torr.

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

TGHT and TBHT will be ramped up to 820A and 230A, respectively.

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

 Wednesday, April 22, 2015, 15:23

TGHT = 200A, 2.26V; TBHT = 117A, 1.58V

IGP1 = 9.8e-6 Torr.

Increasing auto-ramp to 0.4A/min and 0.2A/min for the TGHT and TBHT respectively.