Tuesday, January 22, 2013, 12:38

This is to test the newly developed RFQ target to be commissioned this year.  The purpose of this test is to see how well the RFQ components can sustain the high temperature.  One thermocouple is connected inside the target and the other is connect outside of the Cu heat-shield.  RGA will be running to analyze the gasses. 

TGHT will be auto-ramped up at the rate of 5A/20min to max current at 1000A.  

More info later... 

Wednesday, February 06, 2013, 16:11 

Heat testing Test#1 complete.  Data acquisition in progress....  The test was successful. 

Re-heating Test#2 is in progress.  This time, with a new re-design target container (less black block mass).  Two thermocouples are connected:  One on the back block and the other inside the RFQ components.  

The TGHT current will go up to at least 580A and the gasses will be monitored with the RGA. Ramping rate:  0.5A/min.  Set final current at 400A for now. 

TBHT will remain off at this point until we can know the temperature when TGHT is up to 580A.  

 Thursday, February 07, 2013, 11:39

TGHT reached to 400A/6.30V. 

Back block temperature measured at 18.307mV = 1003 C. 

RFQ component temperature measured at  = 143 C.

TGHT will be ramped up to 580A. 

Continue to monitor...

 Saturday, February 09, 2013, 09:40

TGHT at 580A, TBHT at 271A (setpoint).  Seeing CO2 gassing out.  Ramped down TBHT to zero A and continue to monitor.

Tuesday, February 12, 2013, 16:39  

TGHT heated up to 580A and remained at that current over the long weekend.  

The thermocouple on the back block was reading wrong because the wires away from the tip were fused to the container at high current.  (see attachment #1) 

TBHT was ramped up to 300A and then lower to 280A; mass 32 (CH3OH), and 44 (CO2) were detected.  This is unusual at 580A = 1200C. 

Both TBHT and TGHT were ramped down to zero and the outgassing of these molecules continue to detect on the RGA. (see attachment #2).  Suspect of these gasses from the Cu heat-shield or the thermocouple SiO insulator.

For complete process on screenshots, see my dropbox.

Next:  Coat this container with TaC and use for the SiC target.

 Monday, February 18, 2013, 16:28

The RFQ target container is coated with TaC and ready to be sintered.  No Ta-heat shields are used.  This container will be used for the SiC#28-LPSIS-RFQ. 

Two thermocouples are welded on the container:  One on the end cap and the other on the back block (see attachment#1)

The target will be heated to at least  TGHT at 580A and TBHT at 300A; the vacuum and gasses will be monitored.  

The chamber is currently being pumped down...  

 Friday, February 22, 2013, 14:24

The gasses were analyzed with the RGA:

TGHT @ 520A, TBHT @ 300A:  Mass 28 (CO) reached to max current of ~5pA before the current started to decrease, (see attachment #2).  This could be the indication of the material(s) in the target container was "sort of" fully reduced. 

TGHT was further ramped up  to 600A and heated for a few hours.  The temperature on the end was measured at 1252C and the center block was at 1580C.  (see attachment #3).

The container was successfully sintered with TaC. 

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...  

 A thermocouple feedthru was installed via 9 pin sub-D connector. It runs from the the conflat cross on the top of the evaporator to the upper 9 pin connector of the target mounting plate.

 Tuesday, May 07, 2013, 16:48

5 BeO pellets were made.  Each weights about 1.3 g (including org mass). 

A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Pictures)

Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat.

The chamber was pumped down. 

TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr.

The pressure, voltage and current will be closely monitored. 

If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).

Nikita Bernier wrote:

Tuesday, May 07, 2013, 16:48   5 BeO pellets were made.  Each weights about 1.3 g (including org mass).  A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Attachments) Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat. The chamber was pumped down.  TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr. The pressure, voltage and current will be closely monitored.  If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).

 Monday, May 13, 2013, 12:48

TGHT has been at 600 A for about 13 hours with stable very low vacuum (10^-7). See Attachment #1.

Temperature measurement has been lost on Saturday. Last measurement was was above 1350°C, at around 480 A.

TGHT was ramped down at 1 A/min.

The chamber will be vented later today. The pellets and the thermocouples will be inspected.

Nikita Bernier wrote:

Nikita Bernier wrote:  Tuesday, May 07, 2013, 16:48   5 BeO pellets were made.  Each weights about 1.3 g (including org mass).  A piece of Re foil (0.002" thick) is used as the under layer to protect the reaction between Be(g) and the Ta-boat.  (see Attachments) Another layer of Ta-foil is used as the heat-shield to wrap around the Ta-boat. The chamber was pumped down.  TGHT will be ramped up to 600 A (~1360°C) at 0.2 A/min. The vacuum limit parameter was set for good vacuum at < 3.0e-5 Torr and bad vacuum at > 4.0e0-5 Torr. The pressure, voltage and current will be closely monitored.  If the Ta-boat survives, the TGHT will continue to ramp up to max 800 A (~1580°C).    Monday, May 13, 2013, 12:48   TGHT has been at 600 A for about 13 hours with stable very low vacuum (10^-7). See Attachment #1. Temperature measurement has been lost on Saturday. Last measurement was was above 1350°C, at around 480 A. TGHT was ramped down at 1 A/min. The chamber will be vented later today. The pellets and the thermocouples will be inspected.

 Monday, May 13, 2013, 17:21

The following table shows the characteristics of the pellets after sintering at 600 A for 13 hours.

Sample,   Mass (g),   Thickness (mm),   Density (g/cm3),    Diameter (mm)

1    0.8904 4.875 1.364 13.058

2    0.8991 4.744 1.396 13.148

3    0.8846 4.579 1.482 12.884

4    0.9142 4.981 1.254 13.650

5    0.9022 4.978 1.250 13.586

Avg 0.8981 4.831 1.345 13.265

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.

 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.

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.

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.

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 

There was no signal going from the coils to the PLC. After manipulating the connection points on the coil a signal could again be established. Frequency is ~ 40Hz.

Monday, March 10, 2014, 11:44

Rick replaced the backing pump hose from 1.5" to 2.0" for better flow.  And the HEPA filter was checked - it looks OK.

Monday, March 10, 2014, 11:45

The chiller tripped off on March 7, 2014.

• Water is not flowing into the chiller; paddle wheel shows no signal.
• Tried turning on the chiller locally; a few seconds later, it tripped off. 
• Motor is not responding;
• EPICS is not responding;
• All other water flow signals to TGHT, TBHT, HS, are responding;

Continue investigating...

 Monday, March 10, 2014, 14:36

The water line to the chiller is disconnected, and is re-connected straight to the TGHT power supply.  The paddle wheel is responding - the cooling line in the power supply is not blocked.

It is confirmed the chiller is broken. 

Will discuss if we can use the Evaporator without a chiller but with the DI water connected directly to the TGHT power supply....

Friday, March 14, 2014, 14:50  

The chiller was replaced with a "new" one.  

Checked the chiller interlock - It's working.  

The evaporator is now operational. 

 Friday, March 21, 2014, 16:19

Note about Auto-ramping program.

Previously the auto-rampiong program takes the Chiller as part of the reference to the interlocks.  Because the New chiller is not connected to EPICS; all the references to the Chiller on the auto-ramping program has been removed in order for it to function. 

Thursday, March 27, 2014, 17:38

TEST #1

WC slurry was prepared in non-aqueous environment (see lab book for procedures).  The solution was dripped on two Ta plates (3.1cm2) and let dry. 

Another Ta plate (3.1 cm2) was sprayed with TaC coating (for comparison).

All 3 coated Ta plates are put in a target boat and the boat is wrapped with 3 layers of Ta-heat shields.

HS water valves open; no leaks detected.

TGHT will be ramped up to 700A at 2.0A/min.

RGA is running and gases are being monitored.  See link:

https://www.dropbox.com/sh/625xl7zgepbybmu/GQJTlMo-5a

 Friday, March 28, 2014, 09:13

TGHT reached to 700A and samples were heated up over night. 

Cooling down Evap at 4A/min. 

 Tuesday, April 01, 2014, 17:37

Previous samples, namely WC#1, #2, TC#1 were fully sinterred.  See above link for photos.

TEST#2

Samples WC#3, #4, #5 are sprayed coated with WC solution.  Grains were pre-treated at 400RPM.

These 3 new samples are loaded in a boat, wrapped with 3 layers of Ta-heat shields.

Chamber is pumped down; no water leaks are detected.

TGHT will be ramped up to 700A at 2.0A/min

RGA is running.

Samples were analyzed with SEM/EDX.  The results are inconclusive because W and Ta peaks are very close together.  And WC coated layer may be even too thin to analyze. 

 Monday, April 14, 2014, 16:32

Test#3:  Coated WC on Endcap.  Total mass WC ~350mg.

Sintered at 500A/9.5V; measure temperature on actual sample surface ~1700C.  Sample heated >24hr.

Cooling down TGHT at 2A/min.  IG currently at 3.1e-7 Torr.

 Thursday, April 24, 2014, 17:25

The purpose of this experiment is to see if the carbon mesh is suitable for coating and sintering with uranium carbide.  For this test, the mesh is coated with WC slurry (previously prepared).

 The carbon mesh disks are bought from ERG aerospace corporation; the specifications of the mesh can be found on the link:  http://www.ergaerospace.com/RVC-properties.htm

Photos, EDX, SEM, RGA, etc... and be found on this link:  https://www.dropbox.com/sh/6ic932wu8yl9ad2/7rHFTiSzLY

Thursday, April 24, 2014, 17:51 

TEST #1:  Carbon Mesh, WC - RF sputtered - Then WC coated and sintered.

Target boat is loaded with a piece of WC coated carbon mesh (1/4 size cut out with the laser cutter).  Chamber is pumping down, currently at 3.2e-6 Torr.

HS water valve open - no leaks are detected. 

TGHT will be ramped up to 500A at 1.0A/min. 

RGA is running.  

Material temp will be measured... 

Monday, May 05, 2014, 17:35

Test #1:

TGHT was ramped up to 680A/13.77V.  Vacuum was at 1.62e-6 Torr (and coming down).  Carbon mesh was heated up to 1900C.   See the link to the dropbox above for more results.

Monday, May 05, 2014, 17:39

Test #2:  Carbon mesh (pure) coated with WC - then sintered. 

Chamber has been pumped down to 3.5 e-6 Torr. 

Sample will be heated up to 500A at 1.0A/min.  (Then step up to 680A while monitoring the vacuum).

RGA is running. 

 Wednesday, May 07, 2014, 14:36

Observations:

TGHT was at 650A/12.96V for 6 hrs and temperature was measured at 1930C. 

At some point after that (~20:40hr on May 6), the voltage went up to 14.77V (current remained constant at 650A), the temp went up 2110C - for only about 45 minute before the voltage dropped

back down to 12.53V and the temperature ~1800C.  Is the boat creaking more??? There were a few crack lines on the boat after Test#1. 

Today, TGHT was raised up to 725A and after an hour at that current the temperature was measured at 1930A. 

Now, at Wednesday, May 07, 2014, 14:47 - Lowered the current back to 685A/13.78V - temperature measured at 1900C. 

One thing to note... the vacuum is showing a lot of spikes but remains at around 7.5e-7 Torr. 

The RGA/Current/Voltage/Temp can be found here: https://www.dropbox.com/sh/1yaa7ez3nydl67m/8v4ZRT2slq

Thursday, May 29, 2014, 16:56 

The process is done. Chamber was vented...

Purpose: Sinter one sample of each of TiC, VC, Cr3C2, ZrC, NbC, Mo2C, TaC, and WC on 5x10 mm tantalum foil to see if the samples are usable for SEM.

Samples were prepared using a solution of PEG (2.56 g), PVB (2.45 g), paraffin oil (1.12 g), MEK (15 mL), and EtOH (23 mL). Slurries made using 0.0013 mol of each carbide with ~230 uL of the solution. Applied via paintbrush onto 5x10 mm tantalum foil. 

The samples were placed directly on the target boat, no graphite layer between. We will check to see if the tantalum foil fuses to the boat or not.

Currently (May 29th), the chamber is still pumping down. John and I will continue the procedure tomorrow.

 Pressure down to 7.1e-7 Torr. Water valve to heat shield was opened; pressure remained stable. 

Current turned up to 40 A for now.  Will increase at 2 A/min up to 500 A over the weekend, then on Monday we will turn it up to 600 A and check the temperature. 

Auto-ramp started. Max current = 500 A, voltage = 11.05 V. Current is being increased at 2 A/min. In the first 20 minutes, the pressure went up to about 10E-6 T, but has slowly decreased since then. Everything looks ok. The system will be left until Monday morning (June 9th).