Laura Lambert wrote:

John Wong wrote: John Wong wrote: Laura Lambert wrote: John Wong wrote: Tuesday, September 01, 2015, 17:16 Target container contains 533 discs of SiC with packed length of 17cm.  Mass of 533 discs SiC(green)  = 57.8979g Total mass SiC(green) + target container = 1455g Container is wrapped with 3 heatshields; no end caps are inserted yet. Sintering temp at 1800C - TGHT will be set accordingly.  TBHT max at 230A.  Chamber is currently being pumped down.     Wednesday, September 02, 2015, 09:11 HS water valves opened, no leaks detected. IGP1 = 1.15e-6 Torr Tapped up manually to 40A. Waited ~1hr40 for vacuum to stabilize. IGP1 = 3.6e-6 Torr. Max setpoints set to TGHT = 630A and TBHT = 230A, ~1400C Initiating auto ramp at a rate of 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Once max setpoints achieved, will tap up manually until window port becomes coated [as previously observed] Once window port becomes coated will leave at set temp for ~4hrs to continue with outgassing, then cool down, clean window and ramp back up. If LS port still clean, will continue to ramp up to final desired temperature of 1800C.  Wednesday, September 02, 2015, 14:23 IGP1 = 4.0e-5 Torr. Vacuum too high, stopped auto-ramp and tapped down manually. Dropped TGHT down from 80A to 50A Dropped TBHT down from 55A to 50A Wednesday, September 02, 2015, 15:29 Vacuum down to IGP1 = 1.2e-5 Torr. Re-initiating auto-ramp...  Tuesday, September 08, 2015, 10:04 IGP1 = 4.5e-7 Torr. TGHT = 630A, 9.6V TBHT = 230A, 3.2V DV = 0.22V OMEGA RS = 1476C OMEGA LS = 1450C see attached photo for screenshot. will tap up manually with a visual on both window ports...    Tuesday, September 08, 2015, 15:44 TGHT has stepped up to 820A.  Coating on both windows is becoming obvious and it's interfering the temp readers; however, the left window (see attachment, which is further away from the target) is lightly coated than the right.  See attachment for The Temp (and Power) vs current plots. Target will remained heated at the current and will be cooled down later today.    The target will be re-conditioned up to 820A and temp and mass will be re-measured. Plans: The chamber will be vented tomorrow and the target will be taken out to weigh for mass change.  The chamber windows will need to be clean. A piece of Ta foil will be cover in front of the ionizer to trap any loss material (if any).  Tuesday, September 08, 2015, 17:37 TGHT was at 800A for 2 hours before ramping up 820A for another 2 hours heating.  More coating on the right window is observed and temp reading came down to 1340C.  The left window remains the same and temp reads at 1646C.   Ramping TGHT/TBHT to 0A at 2A/min and 1A/min, respectively.    Wednesday, September 09, 2015, 12:27 Result after the sintering process: No yellow crystal formed (compared to previously observed SiC targets that heated up above 1900C).  Total green mass = 57.90g  mass of graphite foil = 0.035g x 533 discs = 18.7g  mass of green SiC = 39.30g  Target container with SiC before sintered = 1455g  Target container after sintered = 1450g  mass loss ~ 5.0g ~ 13% organic mass, as expected!   The target will undergo the re-condition stage, and the temperature will be measured from 600A to 820A.     Wednesday, September 09, 2015, 17:39 Both end-caps are inserted onto the targets.  The total mass (Target, Sintered SiC, end caps, 4x 19"round graphite foils) = 1453g. Target is wrapped with 3 layers of heat shields.   The extraction electrode is wrapped with Ta-foil (see attachment).  This is to trap any lose particle, if any.   Chamber is currently being pumped down, currently at 1.2e-5 Torr.      Thursday, September 10, 2015, 09:55 HS water valves opened this morning, no leaks detected. TGHT and TBHT tapped up manually to 35A. IGP1 = 4.4e-7 Torr, vacuum stable. Initiating auto-ramp at 1.0A/min and 0.5A/min for the TGHT and TBHT respectively with final setpoints of 600A and 230A.

Thursday, September 10, 2015, 12:05  

Changed TGHT to 2A/min and TGHT remains at 1A/min.  Vacuum is table at 1.0e-6 Torr. 

Friday, September 11, 2015, 11:34  

TGHT was at 600A for almost 20 hours.  Vac at 5.2 e-7 Torr.   L-temp at 1490C, R-temp at 1685 (odd?).   Using pyrometer to measure - Right end does seem brighter than the L end.  

Continue to ramp up TGHT.  Date is collected, will be posted later.  

 Friday, September 11, 2015, 11:53

L/R-temp measurements just don't seem normal.  

Ramped up to 220A- temp reads L = 1522C, R = 1722C.  

Ramping down TBHT doesn't change the temp.  

Will cool TGHT/TBHT to 0A at 2A/min & 1A/min, respectively.  

Will vent the chamber on Monday and inspect for any wrong.

 Monday, September 14, 2015, 12:13

The target has taken out for inspection.  No visible damage/problem was observed.  The Ta-foil for loss particle capture only showed some heat marking but no material was trapped. 

Target was weighted, no mass loss was observed.

Try expending the end caps to get a good thermal conductivity and will re-conditiong again.  

 Tuesday, September 15, 2015, 12:31

The end caps have been expended. 

New Ta foils are used for the heat shields.  The foils are cut in 3 1/4" x 12" and wrapped around the target.  (see attachment).  This is to see if the heat is evenly distributed.  

Both omega optical lens are aligned properly.  

Target is installed but the chamber is NOT yet being pumped down.  Awaiting for the fume hood work in B2 level to be complete before the evaporator can be started. 

 Wednesday, September 16, 2015, 17:57

The work in the B2 level is done; the nuclear ventilation for the evaporators is now operational. 

Chamber is currently being pumped down.

 Thursday, September 17, 2015, 12:19

Chamber has been pump down overnight and pressure is currently at 5.8e-7 Torr.

HS valves are opened and no leaks are detected.

Ramping up TGHT/TBHT to 600A at 2A/min and 230A at 1A/min, respectively.

 Thursday, September 17, 2015, 17:58

TGHT has reached to 600A/9.14V.  Both the L and R temperatures are measured at 1710C and 1760C, respectively.  At 600A, the temperature now is about 300C higher compared to that during the sintering process. 

The difference in the temperature could be from Ta surface vs SiC surface.  (But the 2-color IR temp reader shouldn't matter what color it's measuring?!! I don't know!)

Note: 

Both temperature readings are fairly close.  Could this be improved from the new Ta-foils?  Possible!

It is still unclear what is the absolute temperature.  A more systematic student needs to be done. 

Using a thermocouple couple to measurement the endcaps at 600A and compared with the Omage reader may help to understand more. 

After discussing with Friedhelm, it is decided to stay the target at 600A for the conditioning process. 

 Friday, September 18, 2015, 09:10

Target has been heated at 600A at stable temperature at 1716C (LS) and 1769C (RS), see attachment. 

 Friday, September 18, 2015, 11:45

Initiated cooling down at 2A/min for TGHT, and 1A/min TBHT. 

Currently vac at 5.48e-7 Torr.

 Thursday, September 24, 2015, 11:31

Target was inspected after the 2nd conditioning, up to 1700C at 600A for overnight. 

No solid particle was observed that might have extracted from the ionizer tube.  

The heat shields have been removed and the target is ready for assembly. 

Laura Lambert wrote:

Thursday, September 24, 2015, 08:39 IGP1 = 6.5e-7Torr HS water valves opened, no leaks detected. Tapped up manually to 35A. Waited ~20min. Vacuum stable, IGP1 = 1.5e-6 Torr. Initiated auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively with final setpoints of 250A and 230A. Final temp of 1200C on auto-ramp in order to initiate temperature measurements starting at ~1200C. Thursday, September 24, 2015, 10:24   IGP1 = 8.7e-7 Torr TGHT = 44A, TBHT = 38A Increasing auto-ramp to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.

 Thursday, September 24, 2015, 12:04

 A few notes about the target container:The Ta-foil is cut in a full length of the target container, and that also covers up the back block, and the container is wrapped with 3 sheets (see attachment)

 The inner tube is coated with TaC, using the "flushing technique" - the coating looks much better; will see how it turns out after the sintering process

The target will be heated up to 1900C .  Due to the new wrapping of the Ta-heat shield, the heat distribution may be different.  So the target heater will be ramped up to achieve the desired temperature.  

Thursday, September 24, 2015, 18:45  

TGHT reached to 250A3.6V, TGHT at 230A and stayed for 1.5 hours.  Temp-L = 1280C, Temp-R = 1360C.  

Auto-ramp TGHT to 500A at 1A/min and heat at that current for overnight.  Will take temp reading tomorrow.  

Thursday, September 24, 2015, 23:08  

TGHT has reached to 500A/8.57V.  Temp-L = 1895C, Temp-R = 2073C. (Not sure why the temperature is real, will need to investigate more to get an absolute temp)

Just to be safe… Ramping down TGHT to 425A (according to e-log id 216, Temp-R reached to 1800C with TGHT at 425A/6.84V, but no temp measured for the left at that time)

Will check again later.

Friday, September 25, 2015, 11:52  

The target has been heated at 420A for ~12hours; temp measured ~1900C, slightly higher than the previous target container (W.O#40860-1); the Ta-wraping could affect the heat distribution.  

The temperature is also confirmed by using the 2-C digital pyrometer.  The tube inner surface is measured about 1900C, and the ionizer tube is about 2400C.  (see attachment #2).

Initiating auto-cooling at 2A/min for TGHT and 1A/min for TBHT.

The target will be inspected next Monday

 Wednesday, September 30, 2015, 16:01

The target container is fully sintered (see attachment#3) 

It is still in the discussion where this container will be used online for the UCx.  Nevertheless, the target contain is ready and it looks pretty good. 

John Wong wrote:

Laura Lambert wrote: Thursday, September 24, 2015, 08:39 IGP1 = 6.5e-7Torr HS water valves opened, no leaks detected. Tapped up manually to 35A. Waited ~20min. Vacuum stable, IGP1 = 1.5e-6 Torr. Initiated auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively with final setpoints of 250A and 230A. Final temp of 1200C on auto-ramp in order to initiate temperature measurements starting at ~1200C. Thursday, September 24, 2015, 10:24   IGP1 = 8.7e-7 Torr TGHT = 44A, TBHT = 38A Increasing auto-ramp to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.      Thursday, September 24, 2015, 12:04  A few notes about the target container:The Ta-foil is cut in a full length of the target container, and that also covers up the back block, and the container is wrapped with 3 sheets (see attachment)  The inner tube is coated with TaC, using the "flushing technique" - the coating looks much better; will see how it turns out after the sintering process The target will be heated up to 1900C .  Due to the new wrapping of the Ta-heat shield, the heat distribution may be different.  So the target heater will be ramped up to achieve the desired temperature.   Thursday, September 24, 2015, 18:45   TGHT reached to 250A3.6V, TGHT at 230A and stayed for 1.5 hours.  Temp-L = 1280C, Temp-R = 1360C.   Auto-ramp TGHT to 500A at 1A/min and heat at that current for overnight.  Will take temp reading tomorrow.   Thursday, September 24, 2015, 23:08   TGHT has reached to 500A/8.57V.  Temp-L = 1895C, Temp-R = 2073C. (Not sure why the temperature is real, will need to investigate more to get an absolute temp) Just to be safe… Ramping down TGHT to 425A (according to e-log id 216, Temp-R reached to 1800C with TGHT at 425A/6.84V, but no temp measured for the left at that time) Will check again later. Friday, September 25, 2015, 11:52   The target has been heated at 420A for ~12hours; temp measured ~1900C, slightly higher than the previous target container (W.O#40860-1); the Ta-wraping could affect the heat distribution.   The temperature is also confirmed by using the 2-C digital pyrometer.  The tube inner surface is measured about 1900C, and the ionizer tube is about 2400C.  (see attachment #2). Initiating auto-cooling at 2A/min for TGHT and 1A/min for TBHT. The target will be inspected next Monday  Wednesday, September 30, 2015, 16:01 The target container is fully sintered (see attachment#3)  It is still in the discussion where this container will be used online for the UCx.  Nevertheless, the target contain is ready and it looks pretty good.

 Tuesday, October 06, 2015, 15:09

After further discussion, we are going to reheat this container to 420A.  The temperature will be measured with the thermocouple - probe inside the centre of the tube - and the 2C-IR for comparison. 

This test is to ensure that the container is actually heated to 1900C before the UCx material can be loaded

The chamber has been pumped down to 1.92e-6 Torr.  Heat shield valve is open and no leaks are detected. 

Ramping up TBHT to 230A max and TGHT to achieve ~1900C

 Wednesday, October 07, 2015, 11:12

Yesterday...

TBHT ramped up to 230A and TGHT was at 160A before taking temperature readings. 

TGHT from 160A to 423A, IR2C temp reading increases linearly from 1138C to 1900C, whereas the thermocouple readouts are not quite linear, 1040C to 1748C (see attachment)

After 18 hours, both temp reader dropped about 45C. 

Increased TGHT to 440C, IR2C & thermocouple currently read 1912C & 1762C, respectively. 

 Wednesday, October 07, 2015, 12:28

Lowered TBHT to 200A and TGHT remained at 440A.  IR2C = 1900C, TypeC = 1745C.  Not much affect from TBHT. 

Will increase TBHT back to 230A, then start ramping down TGHT and taking temp readings. 

 Wednesday, October 07, 2015, 17:49

Stepped down TGHT to 160A and TBHT stayed at 230A.  Cooling down temp is generated.  See attachment. 

Notice the overall temp during cooling is lower than that during heating. 

TGHT and TBHT will be ramped down to 0A. 

Chamber will be vented tomorrow. 

More details later...

John Wong wrote:

John Wong wrote: Laura Lambert wrote: Thursday, September 24, 2015, 08:39 IGP1 = 6.5e-7Torr HS water valves opened, no leaks detected. Tapped up manually to 35A. Waited ~20min. Vacuum stable, IGP1 = 1.5e-6 Torr. Initiated auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively with final setpoints of 250A and 230A. Final temp of 1200C on auto-ramp in order to initiate temperature measurements starting at ~1200C. Thursday, September 24, 2015, 10:24   IGP1 = 8.7e-7 Torr TGHT = 44A, TBHT = 38A Increasing auto-ramp to 0.5A/min and 0.2A/min for the TGHT and TBHT respectively.      Thursday, September 24, 2015, 12:04  A few notes about the target container:The Ta-foil is cut in a full length of the target container, and that also covers up the back block, and the container is wrapped with 3 sheets (see attachment)  The inner tube is coated with TaC, using the "flushing technique" - the coating looks much better; will see how it turns out after the sintering process The target will be heated up to 1900C .  Due to the new wrapping of the Ta-heat shield, the heat distribution may be different.  So the target heater will be ramped up to achieve the desired temperature.   Thursday, September 24, 2015, 18:45   TGHT reached to 250A3.6V, TGHT at 230A and stayed for 1.5 hours.  Temp-L = 1280C, Temp-R = 1360C.   Auto-ramp TGHT to 500A at 1A/min and heat at that current for overnight.  Will take temp reading tomorrow.   Thursday, September 24, 2015, 23:08   TGHT has reached to 500A/8.57V.  Temp-L = 1895C, Temp-R = 2073C. (Not sure why the temperature is real, will need to investigate more to get an absolute temp) Just to be safe… Ramping down TGHT to 425A (according to e-log id 216, Temp-R reached to 1800C with TGHT at 425A/6.84V, but no temp measured for the left at that time) Will check again later. Friday, September 25, 2015, 11:52   The target has been heated at 420A for ~12hours; temp measured ~1900C, slightly higher than the previous target container (W.O#40860-1); the Ta-wraping could affect the heat distribution.   The temperature is also confirmed by using the 2-C digital pyrometer.  The tube inner surface is measured about 1900C, and the ionizer tube is about 2400C.  (see attachment #2). Initiating auto-cooling at 2A/min for TGHT and 1A/min for TBHT. The target will be inspected next Monday  Wednesday, September 30, 2015, 16:01 The target container is fully sintered (see attachment#3)  It is still in the discussion where this container will be used online for the UCx.  Nevertheless, the target contain is ready and it looks pretty good.     Tuesday, October 06, 2015, 15:09 After further discussion, we are going to reheat this container to 420A.  The temperature will be measured with the thermocouple - probe inside the centre of the tube - and the 2C-IR for comparison.  This test is to ensure that the container is actually heated to 1900C before the UCx material can be loaded The chamber has been pumped down to 1.92e-6 Torr.  Heat shield valve is open and no leaks are detected.  Ramping up TBHT to 230A max and TGHT to achieve ~1900C  Wednesday, October 07, 2015, 11:12 Yesterday... TBHT ramped up to 230A and TGHT was at 160A before taking temperature readings.  TGHT from 160A to 423A, IR2C temp reading increases linearly from 1138C to 1900C, whereas the thermocouple readouts are not quite linear, 1040C to 1748C (see attachment) After 18 hours, both temp reader dropped about 45C.  Increased TGHT to 440C, IR2C & thermocouple currently read 1912C & 1762C, respectively.   Wednesday, October 07, 2015, 12:28 Lowered TBHT to 200A and TGHT remained at 440A.  IR2C = 1900C, TypeC = 1745C.  Not much affect from TBHT.  Will increase TBHT back to 230A, then start ramping down TGHT and taking temp readings.   Wednesday, October 07, 2015, 17:49 Stepped down TGHT to 160A and TBHT stayed at 230A.  Cooling down temp is generated.  See attachment.  Notice the overall temp during cooling is lower than that during heating.  TGHT and TBHT will be ramped down to 0A.  Chamber will be vented tomorrow.  More details later...

Thursday, October 08, 2015, 12:01  

Test 2: To heat the target container back to ~440A and measure the temperature with the type C thermocouple (inside the tube, away from the centre block) and compared the temp reading with the 2C-IR.   

Chamber is currently being pump down, vac at 9e-6 Torr.  

Will ramp up TGHT to 160A and TBHT to 230A at 2A/min.

 Thursday, October 08, 2015, 17:01

TGHT is now at 440A, TBHT is constant at 230A - IR2C is reading the same as before, 1910C, but Type C is reading lower at 1770C.  (see attachment)

Will keep the current at 440A overnight. 

 Friday, October 09, 2015, 10:06

TGHT has stayed at 440A, TBHT at 230A for ~18hours.  R-temp dropped slightly from 1910C to 1890C and typeC dropped from 1770 to 1756; otherwise the measurements are reproducible. 

After the group discussion, the online heating curve will be re-calculated based on the temp reading from the IR2C curve. 

Next, the target container will be filled with UCx material and the conditioning current for Evap#1 will only go up to 440A (or at least the required current to reach the end of the re-carbonization step). 

So pay attention to the current when heating the target up in EVAP#1.

Initiate cooling at 2A/min for TGHT and 1A/min TBHT

 Friday, October 09, 2015, 11:35

A note about the voltage that may explain the change in the temperature: 

See attachment #2: 

Left plot = Test #1:

Initially TGHT ramped up to 423A and temp measured at 1900C.  Notice, about an hour later, there was a sudden drop in the voltage, and from thereon, the temp was measured at 1860C.  About 18 hours later, TGHT was increased to 440A to achieve 1910C.  

Right plot = Test #2 
Ramped up TGHT to 440A, temp measured 1910C.  At that constant current over the 6 hours period, the voltage slowly increased, and the temperature slightly dropped to 1895C.  

 Wednesday, October 21, 2015, 17:35

This container is prepared for a backup UCx target (otherwise it will be used for development purposes).

The container is coated with TaC; one layer of Ta-heat shield is used. 

TGHT will be ramped up to reach 1900C (previous container had TGHT ramped up to 440A).  

TBHT will be ramped up to max 230A.  

Chamber is currently being pumped down.  

Heating can begin once the vacuum is good, currently at 4.8e-5 Torr. 

 Friday, October 23, 2015, 16:15

TGHT reached to 500A and temp measured at 1940C.  More about the temp plot can be found in the dropbox.

Initiated cooling down at 2A/min. 

Target will be inspected next Monday.

Laura Lambert wrote:

John Wong wrote:  Wednesday, October 21, 2015, 17:35 This container is prepared for a backup UCx target (otherwise it will be used for development purposes). The container is coated with TaC; one layer of Ta-heat shield is used.  TGHT will be ramped up to reach 1900C (previous container had TGHT ramped up to 440A).   TBHT will be ramped up to max 230A.   Chamber is currently being pumped down.   Heating can begin once the vacuum is good, currently at 4.8e-5 Torr.     Thursday, October 22, 2015, 11:36 HS water valves opened, no leaks detected. Tapped up manually to 35A. Vacuum stabilized, initiated auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints TGHT = 300A, TBHT = 230A IGP1 = 1.0e-6 Torr; TGHT = 45.18A, 0.17V; TBHT = 38.4A, 0.41V

 Thursday, October 22, 2015, 17:09

Pressure coming down to 1.5e-6 Torr. 

Increased ramping rate to 2A/min for both TGHT and TBHT.

Laura Lambert wrote:

Thursday, November 05, 2015, 16:19 Springs coated with TaC and loaded into container for sintering. 3x Ta heat shield. EVAP2 currently pumping down.  Friday, November 06, 2015, 08:39 Opened HS water valves, no leaks detected. Tapped up manually to 35A. IGP1 = 5.5e-7 Torr.  Friday, November 06, 2015, 10:08 IGP1 = 5.8e-7 Torr. Vacuum stable. Initiating auto-ramp at 0.2A/min and 0.1A/min with final setpoints of 450A and 230A for the TGHT and TBHT respectively. See photos attached to view how springs were coated and loaded into container.  Monday, November 09, 2015, 09:07 TGHT reached 450A, 7.2V ~8pm sat, nov 7th. OMEGA = 1775C IGP1 = 3.2e-7 Torr. Tapping up manually to 1900C.

 Monday, November 09, 2015, 12:30

Checked the temp on the inner surface (not at the spring) of the container was around 2050C at 500A. 

The TaC coated spring is reading at 1900C; that's what the OMEGA is reading with the setting for 2-colors and slope at 0.98.

Lower TGHT to 450A/ 7.12V.

By comparing the data from the previous temp curve (OMEGA slope at 0.98) with no material inside the container,  the voltage and current plot is aligned with the curve.

Changed OMEGA setting slope to 1.04.  Current temp is reading at 1917C at 450A.

For 2-Color setting, the emissivity should be negligible.  That makes me believe that different materials has different slope setting for the temp reading.  

One thing to note is that, the sintering temp of TaC is around 1900-2000C.  It was clear that the container was fully sintered with TGHT at 450A.

Will need to gather more data with different material to understand the slope setting better. 

Try: 

SiC at 1700C, slope at 1.04

ZrC at 1900C, slope at 104

Ta at 1900C, slope at 0.98.

Compare the data...

 Tuesday, January 19, 2016, 14:19

SiC nanofiber was prepared at UBC Material Engineering Sci.  

4 samples are loaded in a Ta target contained (sintered with TaC coating): 

Sample 1: 

size:  21.70 x 21.54 mm, mass: 0.0762g, thick: 0.224mm

Sample 2: 

size: 20.89mm x 23.95mm, mass: 0.0954g, thick: 0.232mm 

--> Sample 1 and 2 with graphite backing foil 

Sample 3: 

size: 22.55 x 25.56mm, mass: 0.0082g, thick: 0.110mm

Sample 4: 16.93 x 23.82mm, mass: 0.0048g, thick: 0.086mm

--> Sample 3 and 4 with no graphite backing foil. 

(see attachment) 

Test#1:  Heating temperature at 1600C for 24hrs. 

TGHT will be adjusted accordingly.  There are 2 Ta-heat shields wrapped around the container. 

Chamber is currently being pumped down.

 Tuesday, January 19, 2016, 16:19

Vacuum at 2.0e-6 Torr.

For 1600C, expected current is around 350A.

Stepping up TGHT gradually...

 Wednesday, January 20, 2016, 14:34

TGHT was ramped up to 390A/6.63V to reach 1600C.  Samples have been heated at that temp since 11pm last night.

Visual check on the fibers seem ok (see attachment).

Will continue to heat this for a total time of 24hours.

 Wednesday, January 20, 2016, 22:57

Samples have been heated at 1600C for 24hours. 

Initiated cooling at 1A/min.

 Wednesday, January 27, 2016, 12:34

First attempt - heating 1600C.  XRD result showed board "bumps" that could be SiO2? It is inconclusive. 

Second attempt - re-heating the same samples, namely

Sample 1 - only the fiber

Sample 2 - with graphite backing.  This sample is loaded with the fiber facing down to see how well it holds on the graphite foil.  (see attachment)

TGHT will be ramped up to reach 1800C

Chamber is currently being pumped down.

 Wednesday, January 27, 2016, 14:04

Water valves open; no leaks detected.

Ramping up TGHT to 400A at 2A/min

 Wednesday, January 27, 2016, 18:08

TGHT is at 481A to obtain 1800C.

Visual check on Sample 2 - fiber has fallen off graphite backing foil.

Will remain heated at this temperature for over night.

 Friday, February 12, 2016, 11:11

Heat treatment test#1 is complete.  XRD results are inconclusive.  Need to do EDX to determine Si/SiO2.  

(See my dropbox for more details)

Laura Lambert wrote:

Tuesday, February 16, 2016, 14:19 coated with TaC yesterday and let dry overnight. wrapped with one long Ta heat shield - wrapped around tube 3x, with Ta wire to offset Ta foil away from container loaded into evap2 and currently pumping down.  Wednesday, February 17, 2016, 10:51 HS water valves opened, no leaks detected. Tapped up manually to 35A. Waited ~20min, vacuum stable. IGP1 = 5.9e-7 Torr. Initiating auto-ramp at 0.2A/min to a final setpoint of 400A. Final desired temperature = 1900C  Thursday, February 18, 2016, 09:16 IGP1 = 6.6e-7 Torr. TGHT = 303A, 4.3V OMEGA = 1311C Increasing ramping rate to 1.0A/min.

 Thursday, February 18, 2016, 13:10

TGHT reached to 450A, temp at 1800C.  Stepped up TGHT 490A, temp measured at ~1900C. 

Thursday, February 25, 2016, 18:04 Wednesday, February 24, 2016, 17:29

Heat treatment of 2 bullet-shaped Nb samples in a LP-SIS container; it is just that we don't have a target boat. 

Container is wrapped with 12" in total length.  A strip of Nb foil is used as an underlayer for the samples to sit on top. 

Chamber has been pumped down and current vacuum at 1e-6 Torr. 

HS water check - good.

Target temperature 1400C

Ramping up to 250A; this should get to ~1300C.  Will let it heat for over night and step up to 1400C tomorrow. 

 Wednesday, February 24, 2016, 17:59

I'm stopping the heating process because the camera is not working.  I can't monitor the temperature.  Tried to fit the camera; don't now why it fails to connect to the server. 

Will look in to it tomorrow...

 Thursday, February 25, 2016, 08:17

Initiated auto ramping TGHT at 2A/min.

Thursday, February 25, 2016, 17:33  

Finally the camera is fixed.  

Current temperature is at 1126C, TGHT at 250A.  Will step up to reach 1400C. 

Thursday, February 25, 2016, 18:04  

TGHT stepped up to 335A to reach 1400C.  (see attachment) 

Will heat this for few hours and cool it at around 11pm tonight.

 Thursday, February 25, 2016, 22:19

Samples have been heated over 4.5 hours. 

Initiated cool down at 1A/min.

 Friday, February 26, 2016, 15:43

done! all good.

Friday, February 26, 2016, 15:44

5 samples were prepared at UBC MTRL using Sol-gel tetraethyl orthosilicate (TEOS) coated on electrospun polyacrylonitrate (PAN). 

Each sample is sandwiched in between graphite foils. 

Sample labeling:

Direct, 0.2358g

Mix, 0.3486g

3X, 0.2273g

5x, 0.2079g

7x, 0.1735g

All samples are loaded in the target boat, stacking on each other.  The Container is wrapped with 2X- Ta shields.

Chamber is pumping down. 

Step#1 Carbonization temperature: 1600C

 Saturday, February 27, 2016, 10:07

Vac at 2.5e-7 torr.

Ramping up TGHT to 300A at 1A/min. monitoring temp.

Saturday, February 27, 2016, 17:38

TGHT at 400A, temp at 1600C. Vac 1.34e-6 Torr.

 Monday, February 29, 2016, 13:04

Samples have been heated at 1635C for almost 2 days. 

Pressure at 2.1e-7 Torr.

Initiated cooling at 2A/min.

 Thursday, March 24, 2016, 11:26

Samples were analyzed for Si using EDX.  Unfortunately, no Si was found.  The vapour pressure of SiO was too high for it to react with PAN to carbonize in a vacuum environment.  

Will look into a different technique.

Aurelia Laxdal wrote:

Aurelia Laxdal wrote: Aurelia Laxdal wrote: Aurelia Laxdal wrote: Anders Mjos wrote: Laura Lambert wrote: Aurelia Laxdal wrote: Started Ta#47 heating at Evap2 using the autoramp program. The TGHT current is setup to go to 300A (for now) and the TBHT to 230A (final value).  Monday, March 14, 2016, 09:20 One thermocouple was not welded on correctly and is not working.  Cooling evap2 back down, to remove target and re-weld thermocouple. Once thermocouple replaced, will ramp back up and continue with tests/ conditioning of target.    Monday, March 14, 2016, 13:12: Stopped turbo pump  After EVAP2 was vented the thermocouple problem was fixed: it was the wire at on connector inside the box not making proper contact. The lid of the heat shield was also replaced since the one initially mounted had no holes, so one couldn't see the center block. Restarted pumping down at 4:30pm. Just started again the autoramp program: TGHT set to 300A (for the time being) and TBHT to 230A. Temperature measurements will resume tomorrow morning.  Raised the TGHT at 620A. The TBHT was already set at 230A. The temperature is at 1902 deg C. As per John's instructions the target will condition at these setpoints over the week-end. Today, lowered the TGHT from 620A (at 1894 deg C) to 300A.  TBHT is still at 230A.  Cooling down the target.

Thursday, March 24, 2016, 11:29 

Target was removed from the Evaporator.  

The thermocouples broke off.  

Need to insert Re foil prior to installing

Thursday, March 24, 2016, 11:37  

SiC powder (<1um) [10%] was mixed with PAN solution [10%].  Solution was sonicated before e-spinning.  

Fiber mat was binded to graphite foil and heat treated to 250C in air for 1 hour.  

Samples were cut in pieces and rolled up and inserted in Ta target container (TaC coated).  Heat shield was added.

Heat Treatment #1:  

Temperature:  1600C (~350A)

Ramping up TGHT to 300A at 1A/min.  

 Tuesday, March 29, 2016, 11:11

TGHT was maintained at 410A for 1600C for 2 days (see attachment 1).  However at around 22:30 on March 28, there was a sudden increase in voltage.

Temperature raised up to 1750C.  Not sure there was a fault with the control system and it was caused by the Ta-heat shield. (see attachment #2).

 Target was cooled down around 2am on March 29. 

Samples will be removed from the chamber.

Wednesday, March 30, 2016, 11:30

Polycarbosilane fibers were prepared by UBC MTRL. 

Two samples with different fiber sizes were loaded in target boat and wrapped with heat shields.

Samples will be heated up to 1600C.

Chamber is currently being pumped down

 Thursday, March 31, 2016, 16:49

Ramping up TGHT to 300A at 1A/min

 Tuesday, April 05, 2016, 13:02

Samples was heated at 1600C for about 3 hours.  

Then it was cooled down at 2A/min. 

The process is complete. 

Thursday, April 07, 2016, 15:18

E-spun SiC/PAN fiber mats were produced at UBC.

12%PAN solution; 50% SiC to weight of PAN.

Materials used:

1.2g PAN, 8.8g DMF, 0.6g SiC, SDS ~0.1% to SiC

Fiber mats were heat treated at 250C in air.  Then cut into 18" discs and loaded into Ta target boat with heatshield wrapped. 

3 temperature treatments will carry out: 1200C, 1400C and 1600C

Chamber is being pumped down

 Friday, April 08, 2016, 10:02

TGHT at 285A, Temp at ~1200C.  Will remain at this temp for a few hours before cooling down. 

Some samples will be taken out for analysis. 

Next week, temperature treatment will continue at 1400C

 Friday, April 08, 2016, 14:26

Samples have been heated at 1200C for just over 4 hours.

Initiated auto-cooling at 2A/min

 Tuesday, April 12, 2016, 17:51

Heat treatment #2 - 1400C. 

Initial mass after 1200C = 0.0312g

 Monday, April 18, 2016, 12:55

Samples was heated at 1400C (TGHT maintained at ~370A) for 4 days (see attachment 1).

Chamber is vented; samples will be inspected.

 Tuesday, April 19, 2016, 17:49

Results

Sample mass after 1200C = 0.0312g

Sample mass after 1400C = 0.0294g

~5.78% mass  loss. 

Tuesday, April 19, 2016, 17:57

Heat Treatment#3: 1600C

sample mass before heating = 0.0238g (this sample is taken from the batch after it was heated at 1400C)

Chamber is being pumped.

 Thursday, April 21, 2016, 11:07

TGHT stepped up to 330A, temp measured at 1422C.

 Thursday, April 21, 2016, 12:05

TGHT at 415A/7.16V; temp at 1610C

 Thursday, April 21, 2016, 17:49

Temp dropped to 1590.  Increased TGHT to 425A; temp reads 1602A.

 Friday, April 22, 2016, 10:57

Voltage increased to 7.33V, TGHT stepped down to 418A, temp maintained at 1610A.

 Monday, April 25, 2016, 12:08

Sample was heat treated for almost 4 days.  Temperature dropped to 1578C, TGHT at 418/7.26V.  (see attachment #2)

Ramping down TGHT 2A/min.

 Monday, April 25, 2016, 16:00

Result:

Mass after 1600C = 0.0104g, 5.63% mass loss. 

Will do XRD/EDX

Laura Lambert wrote:

Wednesday, May 04, 2016, 13:28 Target boat has a layer of niobium foil on the bottom of the boat. A niobium foil has been made with slots to hold samples [similar to when sintering endcaps] *See attached photos Larger niobium samples are placed in the slots, holding in place, to avoid warping; smaller niobium sample sitting inside the boat by itself. Smaller sample closest to OMEGA IR reading [right side] Boat is wrapped with 1 large layer of Ta foil, wrapped around the boat 3x, careful to avoid touching samples. Loaded into evap2 yesterday. Vacuum pump bearings gone - pump replaced this morning by vacuum group. Pumping down now...  Friday, May 06, 2016, 13:36 HS water valves opened, no leaks detected. Tapped up manually to 35A. IGP1 = 2.4e-7 Torr Setting auto-ramp rate at 0.2A/min to 250A over the weekend. Will tap up manually monday to final desired temperature of 1400C.  Monday, May 09, 2016, 09:38 OMEGA = 1128C IGP1 = 1.3e-7 Torr TGHT = 250A, 3.7V Tapping up manually to 1400C...  Monday, May 09, 2016, 14:05 Evap2 has reached ~1405C TGHT = 341A, 5.34V IGP1 = 1.9e-7 Torr Will remain at max setpoints for min 4hrs then initiate cool down.

 Monday, May 09, 2016, 18:18

TGHT at 341A/5.34V for over 4 hours.  Vac stables at 1.78e-7 Torr.

Cooling down at 2A/min

Wednesday, May 11, 2016, 17:15

Nanofiber SiC (~50nm grain size)/PAN was prepared at UBC. 

SiC 0.50g, DMF 9.0g, PAN 1.0g, tiny bit of SDS.

The fiber mat was stabilized in air at 250C and then cut into discs, initial mass = 0.1072g

Discs were then bounded with PVA on 9 pieces of rounded graphite foil  (green mass gained to 0.6031g)

The stack of naofiber SiC/PAN was loaded on to Ta boated (coated) and wrapped with Ta heat shield. 

Chamber is currently being pumped down.

 Friday, May 13, 2016, 15:00

TGHT at 390A/6.966V.  Temp measured at 1615C. 

Will keep at that temperature for a few days.

 Monday, May 16, 2016, 15:44

Sample has been heated at ~1600C for 4 days.  TGHT at 400A/7.02V. 

Cooling down at 2A/min

 Tuesday, May 17, 2016, 11:18

Chamber vented.  Inspecting samples.

The purpose of this experiment is to determined the limiting operating temperature for Beta-SiC.  To do so, samples will be heated in sequence to observe any volatile Si coated on the window.  The coating is observed above 1400C for the conventional SiC (mixuture of alpha and beta) and this coating leads to HV shorting problem. 

Thursday, May 19, 2016, 14:26

Beta-SiC (size ~1um) slurry was prepared and casted on a graphite foil. 

Discs are cut into D-shape

Average thickness (including graphite foil) = 0.349mm

Graphite foil = 0.13mm

Actual SiC thickness = 0.219mm (close to normal SiC thickness)

Samples are loaded into a target boat.

Total discs = 120

Total mass = 14.3507g

Thursday, May 19, 2016, 14:32

Omega slope set to = 1.04

Heat-treatment #1: 1400C

 Thursday, May 19, 2016, 17:04

TGHT ramping up to 250A at 0.5A/min

Laura Lambert wrote:

John Wong wrote: The purpose of this experiment is to determined the limiting operating temperature for Beta-SiC.  To do so, samples will be heated in sequence to observe any volatile Si coated on the window.  The coating is observed above 1400C for the conventional SiC (mixuture of alpha and beta) and this coating leads to HV shorting problem.  Thursday, May 19, 2016, 14:26 Beta-SiC (size ~1um) slurry was prepared and casted on a graphite foil.  Discs are cut into D-shape Average thickness (including graphite foil) = 0.349mm Graphite foil = 0.13mm Actual SiC thickness = 0.219mm (close to normal SiC thickness) Samples are loaded into a target boat. Total discs = 120 Total mass = 14.3507g Thursday, May 19, 2016, 14:32 Omega slope set to = 1.04 Heat-treatment #1: 1400C  Thursday, May 19, 2016, 17:04 TGHT ramping up to 250A at 0.5A/min    Friday, May 20, 2016, 08:53 IGP1 = 9.2e-6 Torr. Increasing ramping rate to 1.0A/min up to 250A  Friday, May 20, 2016, 09:17 IGP1 = 2.1e-5 Torr TGHT = 215A, 3.1V OMEGA = 1035C Stopping auto-ramp and tapping up manually...  Friday, May 20, 2016, 12:26 OMEGA slope changed to 1.04 OMEGA reached ~1430C and kept there for ~1hr. no change. no coating on window observed tapped up manually to OMEGA =1500C TGHT = 350A, 5.8V  Friday, May 20, 2016, 14:17 Not much change to window. Might be beginning of light dusting, hard to tell. Will be better observed after longer period of time at 1500C Will remain at 1500C over weekend.

 Tuesday, May 24, 2016, 11:15

Sample has been heated over the long weekend.  Temp dropped to 1400C.  TGHT at 350A/5.78V.  Vac at 1.5e-7 Torr.

It is hard to tell if there is any coating on the window.  Will increase temperature to 1800C

 Tuesday, May 24, 2016, 11:43

Temp at 1620C. TGHT at 440A/7.7V. 

At this temperature, the coating would have been seen for the conventional SiC target material.  But, no much of change on the window since the TGHT was tapped up from 1400C.

Continue to increase TGHT to reach 1800C

 Tuesday, May 24, 2016, 11:58

Temp at 1680C/TGHT 470A/8.4C - a very light film on the window was observed.  Not sure if this film was left from previous processes; it is just that the target container is getting very bright and hard to see.

 Tuesday, May 24, 2016, 12:15

TGHT at 510A/9.16V - Observed coating on window.  Omega got interfered, therefore temp is unknown.  But it was read at ~1720C before the window was getting coated and temp started to dropped.

Will leave at this stage for now...

 Tuesday, May 24, 2016, 16:57

Window is fully coated.  Based on the heating curve, at 500A, the temp should be at ~1900C (wrapped with a layer of heat shield).  Temperature reader dropped to1340C due to the coating interference. 

Cooling down TGHT at 2A/min. And will exam the materials tomorrow... 

Laura Lambert wrote:

Wednesday, May 25, 2016, 11:37 Container coated with TaC using 'flushing technique' [cleaned ionizer tube with acetone, so no coating inside ionizer tube] Wrapped with 2 x Ta heat shields - one full height of Ta foil wrapped around cooling fins twice Currently pumping down in evap2  Thursday, May 26, 2016, 09:28 Tapped up manually to 40A IGP1 = 6.6e-7 Torr Initiating auto-ramp at 0.2A/min and 0.1A/min for the TGHT and TBHT respectively. Final setpoints for TGHT = 650A and TBHT = 230A Once max setpoints reached will continue to tap up manually while monitoring temperature to 1900C

 Tuesday, May 31, 2016, 11:09

TGHT at 615A/9.08V, temp = 1610C.  Vacuum at 1.8e-7 Torr. 

Tapping up TGHT to reach 1900C

 Tuesday, May 31, 2016, 12:04

TGHT at 765A/11.90V.  Temp at 1900C.  Pressure is coming down from 8.7e-7Torr. 

Will keep at this temperature for a day.

 Wednesday, June 01, 2016, 15:22

Temperature has been stable at 1900C.  Pressure is coming down from 3.4e-7 Torr. 

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

 Friday, June 03, 2016, 12:10

TGHT/TBHT at 0A.  Target can be remained under vacuum until Monday.

 Monday, June 06, 2016, 16:54

Target container was inspected; it looks good