Laura Lambert wrote:

Laura Lambert wrote: Laura Lambert wrote: Laura Lambert wrote:  Tuesday, May 23, 2017, 14:42 UO2/C green was prepared May 16th, 2017. The cast peeled off the glass nicely May 17th, 2017. Initial UO2 powder used = 50.25g (Inventory R-01032A, UO2 + bottle = 876.80g before use) Graphite powder used = 10.32g Green cast dried UO2/C + organic mass = 61.70g  The green was rolled up and wrapped in a piece of graphite sheet. The Ta-target boat was wrapped with 1 long layer of heat shield and installed in evap1 today. Chamber pumped down today. Target boat will be ramped up to 520A at the rate of 0.1A/min. Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr. IG1 = 4.80e-6 Torr Tapped up to 30A, 0.45V Waited ~1hr, vacuum stable. IG1 = 8.3e-6 Torr Initiating auto-ramp  Wednesday, May 24, 2017, 09:26 IG1 = 5.5e-5 Torr TGHT = 64A, 0.72V Vacuum currently yo-yo-ing. Changing vacuum limits to attempt to speed up process. Vacuum limit stop at 1.0e-4 Torr, backing off at 5.0e-4 Torr. Once vacuum settles and vacuum starts to drop will adjust limits again accordingly.  Wednesday, May 24, 2017, 11:17 IG1 = 1.2e-4 Torr TGHT = 69A, 0.74V TGHT direct readout = 66A, 0.73V Thermometer attached to TP = 41.0C Room temp = 24.0C Wednesday, May 24, 2017, 13:16  Vacuum going well. Stable yo-yo-ing at current vacuum limit. TP = 41.5C, RT = 23.9C IG1 = 1.2e-4 Torr TGHT = 71A, 0.77V Increasing vacuum limit stop to 2.0e-4 Torr. Thursday, May 25, 2017, 13:03 Vacuum has stabilized. TGHT = 188A, 1.85V IG1 = 2.2e-5 Torr. Adjusting vacuum limits so when 2nd phase starts, vacuum does not spike. Vacuum limit stop at 5.0e-5 Torr, backing off at 1.0e-4 Torr.    Friday, May 26, 2017, 13:40 Everything tripped off this morning at around 4:30am This was not due to the vacuum spiking as one would expect. No power bumps according to  ISAC controls. Looking back on elogs  [see elog i.d. 145] evap1 had also tripped off during the last round of carbonizing UO2, however last time everything tripped off ~60A. For last trip off the water valve remained open and on. This time  WV1 showed yellow in the TGHT epics box, off under WV epics box, but black [open] in the WV epics box diagram [see screenshot for better understanding]. Water valves are closed - confirmed in person - water wheels not turning. Trip-off occured ~275A. Vacuum was stable at trip-off point; IG1 ~6e-6 Torr  Reason: currently unknown.        Friday, May 26, 2017, 15:43 Starting pumping down again this afternoon while trying to understand trip-off - no progress on that end. IG1 = 4.9e-6 Torr Tapped up to 40A, 0.24V Vacuum spiked to 2e-5 Torr Backed off to 35A, 0.20V Showing lower voltage output than the last round that had tripped off...but ramping is so early on/ low current, hard to tell... Vacuum stable. IG1 = 5.4e-6 Torr Target boat will be ramped up to 275A [trip-off point] at the rate of 0.1A/min. Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr.   TP = 37.9C, RT = 25.2C    Monday, May 29, 2017, 08:21 Initially it looks like not enough time had been allowed for the vacuum to settle before initiating the auto-ramp resulting in the vacuum spiking and tripping off the system. A closer look shows that is not the case. Note: the vacuum limits were set to stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr.    The TGHT started to back off when the vacuum was ~6e-6 Torr, this is considered a good vacuum and should not have caused the system to initiate backing off yet. Over the course of ~1min, evap1 had backed off all the way down to 0A. At this point the vacuum was now up to ~1.75e-5 Torr and still rising. ~34min after the TGHT had reached 0A, the vacuum eventually reached 8e-4 Torr and tripped off the evaporator. See photos attached.

 Tuesday, May 30, 2017, 07:41

Still unsure as to why evap1 tripped off again.

Put evap1 back under vacuum/ turned turbo pump on and opened isolation valve yesterday afternoon.

Vacuum good this morning...nothing tripped off...

 Tuesday, May 30, 2017, 08:21

IG1 = 2.3e-6 Torr

Tapped up manually to 40A, 0.24V

Waited ~1hr

IG1 = 4.5e-6 Torr

Initiated auto-ramp at 0.2A/min up to a final setpoint of 250A

 Wednesday, May 31, 2017, 09:37

IG1 = 2.4e-6 Torr

TGHT = 250A, 2.57V

Increasing max setpoint to 275A [the trip off point] at a rate of 0.2A/min

Vacuum is currently stable and low; increasing limits to:

Vacuum limit stop at 1.0e-4 Torr, backing off at 5.0e-4 Torr.

 Wednesday, May 31, 2017, 13:39

IG1 = 3.7e-6 Torr

TGHT = 275A, 2.80V

Increasing max setpoint to final setpoint of 520A at a rate of 0.2A/min

Vacuum is currently stable and low; keeping  current limits.

Wednesday, May 31, 2017, 15:57

IG1 = 8.14e-6 Torr

TGHT = 300A, 3.08V

Vacuum stable.

Decreasing ramping rate to 0.1A/min for overnight heating.

turbo pump = 40.5C; room temp = 25.1C

 Thursday, June 01, 2017, 09:00

IG1 = 4.2e-5 Torr

TGHT = 396A, 4.06V

Vacuum stable.

Increasing ramping rate to 0.2A/min.

turbo pump = 41.6C; room temp = 24.3C

 Thursday, June 01, 2017, 13:18

IG1 = 1.25e-4 Torr

TGHT = 439A, 4.48V

Vacuum stable.

Changing vacuum limits.

Vacuum limit stop at 2.0e-4 Torr, backing off at 5.0e-4 Torr.

turbo pump = 42.3C; room temp = 24.6C

 Thursday, June 01, 2017, 15:48

IG1 = 1.95e-4 Torr

TGHT = 467A, 4.81V

Vacuum stable.

Changing vacuum limits and ramping rate for heating overnight.

Decreasing ramping rate to 0.1A/min

Vacuum limit stop at 1.0e-4 Torr, backing off at 5.0e-4 Torr.

turbo pump = 44.1C; room temp = 25.3C

 Friday, June 02, 2017, 07:19

IG1 = 1.26e-4 Torr

TGHT = 473A, 4.77V

Vacuum stable.

Changing vacuum limits and ramping rate.

Increasing ramping rate to 0.2A/min

Vacuum limit stop at 2.0e-4 Torr, backing off at 5.0e-4 Torr.

 Friday, June 02, 2017, 10:18

IG1 = 2.04e-4 Torr

TGHT = 498A, 5.08V

Vacuum stable.

Changing vacuum limits.

Vacuum limit stop at 3.0e-4 Torr, backing off at 5.0e-4 Torr.

Fan has been inserted - pointed at turbo pump, TP temp's have decreased.

tp = 32.1C; rt = 24.7C

 Friday, June 02, 2017, 13:22

IG1 = 2.4e-4 Torr

TGHT = 520A, 5.40V

Vacuum stable and decreasing.

Carbonization process almost complete.

Will remain at max setpoints over the weekend.

TP = 28.2C; RT = 24.5C

 Monday, June 05, 2017, 08:51

IG1 = 1.75e-6 Torr

TGHT = 520A, 5.29V

Carbonization process complete!

Remained at max setpoints over the weekend.

Initiating auto cool at 1.0A/min

 Tuesday, June 06, 2017, 15:56

Vented in Ar and removed today.

Currently in glove box.

 Monday, June 12, 2017, 11:44

Flakes produced: 48.00g

 Monday, June 12, 2017, 11:41

UO2/C green was prepared June 7th, 2017.

The cast peeled off the glass nicely June 8th, 2017.

Initial UO2 powder used = 50.10g (Inventory R-01032A, UO2 + bottle = 776.36g before use)

Graphite powder used = 10.06g

Green cast dried UO2/C + organic mass = 62.98g 

The green was rolled up and wrapped in a piece of graphite sheet.

The Ta-target boat was wrapped with 1 long layer of heat shield [reused from last carbonization] and installed in evap1 this morning.

Chamber pumped down.

Target boat will be ramped up to 520A.

Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr.

IG1 = 1.58e-5 Torr

Tapped up to 30A, 0.21V

Waited ~1hr45, vacuum stable.

IG1 = 8.59e-6 Torr

Initiating auto-ramp at 0.1A/min

 Tuesday, June 13, 2017, 10:32

IG1 = 5.0e-5 Torr

TGHT = 65A, 0.47V

Vacuum currently yo-yo-ing, but stable.

Changing vacuum limits.

Vacuum limit stop at 2.0e-4 Torr, backing off at 5.0e-4 Torr.

Increasing ramping rate to 0.2A/min.

Thursday, June 15, 2017, 16:24  

IG1 = 1.96e-4 Torr

TGHT = 520A, 5.18V

TGHT has reached 520A, the vacuum remains at it's limit.

Vacuum usually drops and stabilizes slightly before the max setpoint is reached indicating carbonization process complete.

Since vacuum remains high, this indicates the carbonization remains incomplete.

Conditions have changed such as vacuum limits, which has greatly sped up the process.

This increase in speed could have an impact on the current at which the carbonization occurs.

Increasing max setpoint to 530A and re-initiating auto-ramp.

 Friday, June 16, 2017, 08:32

Vacuum stable, started decreasing when TGHT reached 530A - carbonization process complete.

Evap1 has remained at max setpoints for ~11hrs, but has remained at low vacuum for ~5hrs.

IG1 = 5.56e-6 Torr

TGHT = 530A, 5.31V

Initiating auto-cool at 1.0A/min

TP = 24.9C, RT = 24.3C

*note TP now has water cooling as well as fan pointed at it for this entire process

 Monday, June 19, 2017, 16:16

Vented in Ar and transferred from evap1 to glove box this a.m

UC2 flakes produced = 48.66g

 Wednesday, September 27, 2017, 09:25

UO2/C green was prepared Sept 20th, 2017.

The cast peeled off the glass Sept 22nd, 2017 - not quite enough 'special' ingredient.

UO2 stuck to glass around edges of cast - a lot of flakes produced while peeling off.

Initial UO2 powder used = 50.00g (Inventory R-01032A, UO2 + bottle = 726.38g before use)

Graphite powder used = 10.03g

Green cast dried UO2/C + organic mass = 60.38g 

The green was rolled up and wrapped in a piece of graphite sheet.

The Ta-target boat was wrapped with 3-layers of heat shield [reused from last 1stepUCx] and installed in evap1 yesterday afternoon.

Chamber pumped down overnight.

Target boat will be ramped up to 520A.

Vacuum limit stop at 5.0e-5 Torr, backing off at 6.0e-5 Torr.

IG1 = 3.5e-6 Torr

Tapped up to 30A, 0.43V

Waited ~50min, vacuum stable.

IGP1 = 8.6e-6 Torr

Initiating auto-ramp at 0.1A/min

 Wednesday, September 27, 2017, 13:28

IGP1 = 1.4e-5 Torr

TGHT = 38.5A, 0.48V

Vacuum stable.

Changing vacuum limits and ramping rate.

Vacuum limit stop at 2.0e-4 Torr, backing off at 5.0e-4 Torr.

Increasing ramping rate to 0.2A/min.

 Thursday, September 28, 2017, 08:41

IGP1 = 3.26e-5 Torr

TGHT = 174A, 1.71V

Vacuum stable.

Increasing ramping rate to 0.5A/min.

 Thursday, September 28, 2017, 09:56

IGP1 = 4.85e-5 Torr

TGHT = 195A, 1.92V

Vacuum initially climbed a small amount with last increase, has started to decrease - vacuum stable.

Increasing ramping rate to 1.0A/min.

Thursday, September 28, 2017, 10:30  

IGP1 = 5.3e-5 Torr

TGHT = 220A, 2.18V

Vacuum increased slightly again with faster ramping rate.

Vacuum now dropping - stable.

Increasing ramping rate to 2.0A/min.

 Thursday, September 28, 2017, 11:07

IGP1 = 6.35e-5 Torr

TGHT = 302A, 3.09V

Vacuum increased slightly again with faster ramping rate.

Vacuum now dropping - stable.

Increasing ramping rate to 2.5A/min.

Thursday, September 28, 2017, 11:45

IGP1 = 1.67e-4 Torr

TGHT = 380A, 4.04V

Vacuum increased normally at slow rate for first half hour.

~30min into the 2.5A/min rate increase, vacuum started to climb much faster.

Paused auto-ramp for few min to allow vacuum to stabilize.

Vacuum decreasing - stable.

IGP1 = 1.4e-4 Torr

Decreasing ramping rate to 0.5A/min for next hour while unable to watch.

 Thursday, September 28, 2017, 13:20

IGP1 = 1.93e-4 Torr

TGHT = 425A, 4.58V

Vacuum stable.

Changing vacuum limits and ramping rate.

Increasing ramping rate 1.0A/min.

Vacuum limit stop at 3.0e-4 Torr, backing off at 6.0e-4 Torr.

 Thursday, September 28, 2017, 14:06

IGP1 = 3.1e-4 Torr

TGHT = 456A, 4.93V

Vacuum stable.

Changing vacuum limits and ramping rate.

Changing ramping rate to 0.5A/ 30sec.

Vacuum limit stop at 4.0e-4 Torr, backing off at 7.0e-4 Torr.

 Thursday, September 28, 2017, 14:44

IGP1 = 4.0e-4 Torr

TGHT = 468A, 5.07V

Vacuum stable.

Changing vacuum limits.

Vacuum limit stop at 5.0e-4 Torr, backing off at 8.0e-4 Torr.

 Thursday, September 28, 2017, 15:49

TP thermocouple = 28.1C

IGP1 = 5.0e-4 Torr

TGHT = 485A, 5.25V

Vacuum stable.

Changing ramping rate for overnight heating.

Decreasing ramping rate to 0.5A/min.

 Friday, September 29, 2017, 09:11

TP thermocouple = 26.1C

IGP1 = 5.0e-6 Torr

TGHT = 520A, 5.60V

Vacuum stable.

Carbonization process complete!

Evap1 has remained at max setpoints for ~13hrs

Initiating auto-cool at 1.0A/min

 Tuesday, October 03, 2017, 10:09

Vented in Ar and transferred from evap1 to glove box yesterday.

 Tuesday, October 10, 2017, 14:11

UO2/C green was prepared Oct 4th, 2017

The cast peeled off the glass nicely Oct 6th, 2017

Initial UO2 powder used = 50.26g (Inventory R-01032A, UO2 + bottle = 676.34g before use)

Graphite powder used = 10.12g

Green cast dried UO2/C + organic mass = 61.30g 

The green was rolled up and wrapped in a piece of graphite sheet.

The Ta-target boat was wrapped with 3-layers of heat shield [reused] and installed in evap1 this morning.

Chamber currently pumping down.

Target boat will be ramped up to 520A.

Vacuum limit stop at 3.0e-4 Torr, backing off at 6.0e-4 Torr.

 Wednesday, October 11, 2017, 09:06

IGP1 = 1.74e-6 Torr

Tapped up to 35A, 0.29V

Waited ~70min, vacuum stable.

IGP1 = 6.9e-6 Torr

Initiating auto-ramp at 0.2A/min

 Wednesday, October 11, 2017, 13:06

IGP1 = 3.1e-4 Torr

TGHT = 61A, 0.49V

Vacuum stable.

Changing vacuum limits.

Vacuum limit stop at 5.0e-4 Torr, backing off at 8.0e-4 Torr.

 Thursday, October 12, 2017, 08:31

IGP1 = 1.06e-5 Torr

TGHT = 275A, 2.55V

Vacuum stable.

Increasing ramping rate to 0.5A/min.

 Thursday, October 12, 2017, 09:03

IGP1 = 1.47e-5 Torr

TGHT = 290A, 2.70V

Vacuum stable.

Increasing ramping rate to 1.0A/ 30sec.

 Friday, October 13, 2017, 08:30

IGP1 = 5.8e-6 Torr

TGHT = 520A, 4.98V

Vacuum stable.

Carbonization process complete!

Evap1 has remained at max setpoints for ~17hrs

Initiating auto-cool at 1.0A/min

 Tuesday, October 17, 2017, 15:01

TGHT had sat at 0A for at least 24hrs.

At ~3:30-4am this morning everything tripped off. The only thing remained on was the roughing pump.

Power bump? Did someone accidentally turn it off? Will follow up on this...

Vacuum was sitting at ~3.5e-2Torr when I noticed today.

Most vacuum had been lost, but there was still a small vacuum - materials should be okay.

Purged and vented in Ar.

Transferred materials to glove box.

 Wednesday, January 10, 2018, 14:44

Circles from cast 1 were used, the same as the last round of 1stepUCx [see elog i.d. 164]

A 14mm punch was used to punch out circles from the cast.

35 circles were packed into a graphite sample container.

35 x UO2/C circles = 5.75 g

Graphite container = 5.38 g

Graphite container is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3-layers of heat shield and installed in Evap1.

Chamber currently pumping down.

 Monday, January 15, 2018, 13:37

35 circles of 14 mm diameter were packed into a graphite sample container.

35 x UO2/C circles = 5.58 g

Graphite container = 5.22 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 new Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

Tuesday, January 16, 2018, 13:41 

Initial IGP1 = 9x10e-7 Torr

Tapped up entire process manually to 520A in 1.5 hrs

TGHT = 525 A, 5.64 V

Vacuum coming down nicely indicating carbonization process complete 

Will remain at max setpoint overnight to ensure full carbonization before cooling down.

Wednesday, January 17, 2018, 10:30

Initiating auto-cool at 2.0A/min 

Wednesday, January 17, 2018, 4:30

 Thursday, February 01, 2018, 12:59

35 circles of 14 mm diameter were packed into a graphite sample container.

28 discs corresponded to cats#1 and 7 discs to cast#2

35 x UO2/C circles = 3.42 g

Graphite container = 6.96 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 new Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

 Friday, February 02, 2018, 13:18

Initial IGP1 = 4.82x10e-7 Torr

Tapped up entire process manually to 520A in 30 min

TGHT = 520 A, 5.63 V

Vacuum coming down nicely indicating carbonization process complete 

Will remain at max setpoint for 4 hrs to ensure full carbonization before cooling down.

 Friday, February 02, 2018, 16:57

Initiating auto-cool at 2.0 A/min 

Monday, February 05, 2018, 17:23 

Monday, February 05, 2018, 17:24

35 circles from cast#2 of 14 mm diameter were packed into a graphite sample container.

35 x UO2/C circles = 4.59 g

Graphite container = 5.3 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 new Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

 Tuesday, February 06, 2018, 10:59

Initial IGP1 = 4.79e-7 Torr

Tapped up entire process manually to 520A in 30 min

TGHT = 520 A, 5.32 V

Vacuum coming down indicating carbonization process complete.  

Will remain at max setpoint for 4 hrs to ensure full carbonization before cooling down.

 Tuesday, February 06, 2018, 14:44

Initiating auto-cool at 2.0 A/min 

 Thursday, February 08, 2018, 10:43

Vented with Ar and removed from EVAP1

 Tuesday, February 13, 2018, 11:39

35 circles of 14 mm diameter were packed into a graphite sample container.

35 x UO2/C circles = 5.74 g

Graphite container = 5.20 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

 Tuesday, February 13, 2018, 15:30

Initial IGP1 = 2.73x10e-6 Torr

Tapped up entire process manually to 520 A in 30 min

TGHT = 520 A, 5.41 V

Vacuum coming down nicely indicating carbonization process complete.

Current trip off after 5 min of being at 520 A.

 Wednesday, February 14, 2018, 15:32

EVAP1 vented with Argon and the target was removed.

Target was transferred to glove box.

Ta boat and graphite container look unbroken.

Marla Cervantes wrote:

Tuesday, February 13, 2018, 11:39 35 circles of 14 mm diameter were packed into a graphite sample container. 35 x UO2/C circles = 5.74 g Graphite container = 5.20 g Graphite tube is placed inside a target boat. Boat previously coated with TaC and sintered. Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1. Chamber currently pumping down.  Tuesday, February 13, 2018, 15:30 Initial IGP1 = 2.73x10e-6 Torr Tapped up entire process manually to 520 A in 30 min TGHT = 520 A, 5.41 V Vacuum coming down nicely indicating carbonization process complete. Current trip off after 5 min of being at 520 A.  Wednesday, February 14, 2018, 15:32 EVAP1 vented with Argon and the target was removed. Target was transferred to glove box. Ta boat and graphite container look unbroken.

 Friday, March 02, 2018, 16:31

A test was performed in EVAP1 (see log ID 194):

- A Ta boat without Ta shielding was submitted to 520 A and it remained at that current point overnight.

-No trip off

Marla Cervantes wrote:

Marla Cervantes wrote:  Tuesday, February 13, 2018, 11:39 35 circles of 14 mm diameter were packed into a graphite sample container. 35 x UO2/C circles = 5.74 g Graphite container = 5.20 g Graphite tube is placed inside a target boat. Boat previously coated with TaC and sintered. Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1. Chamber currently pumping down.  Tuesday, February 13, 2018, 15:30 Initial IGP1 = 2.73x10e-6 Torr Tapped up entire process manually to 520 A in 30 min TGHT = 520 A, 5.41 V Vacuum coming down nicely indicating carbonization process complete. Current trip off after 5 min of being at 520 A.  Wednesday, February 14, 2018, 15:32 EVAP1 vented with Argon and the target was removed. Target was transferred to glove box. Ta boat and graphite container look unbroken.  Friday, March 02, 2018, 16:31 A test was performed in EVAP1 (see log ID 194): - A Ta boat without Ta shielding was submitted to 520 A and it remained at that current point overnight. -No trip off

 Friday, May 18, 2018, 18:32

35 circles of 14 mm diameter of cast #3 were packed into a graphite sample container.

40 x UO2/C circles = 4.58 g

Graphite container mass = 6.95 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

Saturday, May 19, 2018, 07:30 

Initial IGP1 = 6.27e-7 Torr

 Tapped to 80A at 10A/10s with 20 s waiting period each 10 A

 Waited 4 min for vacuum to stabilize.

 Tapped to 100 A at 10A/10s with 20 s waiting period each 10 A

 Waited 12 min for vacuum

Tapped to 400 A at 25A/30s with 30 s waiting period each 25 A

Tapped to 520 A at 20A/30s with 30 s waiting period each 20 A

Pressure dropping indicates carbonization complete.

Current tripped off, vacuum was ok, water cooling was ok.

Saturday, May 19, 2018, 10:00 

Current was returned to 520 A manually

Tapped to 100 A at 10A/10s with 20 s waiting period each 10 A 

Tapped to 400 A at 25A/30s with 30 s waiting period each 25 A

Tapped to 520 A at 20A/30s with 30 s waiting period each 20 A

The discs will stay at max current for 4 hrs

 Saturday, May 19, 2018, 18:31

Vented with Argon and removed form evaporator 1

Friday, May 25, 2018, 15:34 

D-shaped discs were cut from cast 3

A 13mm punch was used to punch out discs from pre-cut strips using the old method.

The target consists of 205 discs with 10 cm in length - all single discs, no packs.

205 x UO₂/C discs = 22.04 g

Graphite insert with caps is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3-layers of heat shield and installed in evap1.

Chamber is pumping down.

 Saturday, May 26, 2018, 10:39

Current tapped manually to 80 A at 1A/s in 10 A blocks with a waiting period of 20 s between each increment

18 min waiting for pressure stabilization

Current tapped to 100 A in same rate

Saturday, May 26, 2018, 10:51 

After 9 min current was reduced to 60 A to reduce pressure.

Cuerrent was tapped to 100 A

After 10 min the rate was increased to 25 A each 20 s until 450 A

The rate was changed to 10 A each 2 min until 500 A

Last 20 A were tapped after 1 min 

Saturday, May 26, 2018, 15:41 

After 4hrs the current was reduced in a rate of 10 A /min

Monday, May 28, 2018, 12:45 

EVAPI was vented with Ar and UCx was transferred to glove box.

 Friday, June 01, 2018, 11:20

Target boat was previously coated with TaC and sintered.

Two small C-inserts of ~2cm length were placed on Ta boat

Sample 1-sc: 15 discs of cast 3 made with 1-step cast method (UCx+foil 1.437 g)

Sample 2-sc: 24 discs from rejected discs of 2-step casting (UCx+foil 1.585 g)

Ta boat was wrapped with 3 layers of Ta-heat shield

The chamber is currently pumping down.

TGHT will be ramped up to 495A [same parameters used to reach 1910C in evap2 when sintering TaC coating - elog410 evap2]

Monday, June 04, 2018, 11:27 

IG1 = 4e-7 Torr

Tapped up manually to 35A

Waited 1hr

Vacuum stable.

IG1 = 8.02e-7 Torr.

Initiating auto-ramp (0.1 A/min) up to 80 A

 Tuesday, June 07, 2018, 15:47

Vacuum stable

IG1 = 7.02e-7 Torr.

Changing auto-ramp to 0.02 A/min up to 140 A

Thursday, June 07, 2018, 15:49 

Vacuum stable 5.5e-7 Torr

Current 139 A, voltage 1.25 V

Changing auto-ramp to 0.1 A/min up to 495 

Saturday, June 9, 2018, 10:41 

The material stayed 4 hours at 495 A

Auto-ramp set to -1 A/min down to 0 A 

Monday, June 11, 2018, 17:43 

EVAPI was vented with Ar and UCx was transferred to glove box

 Tuesday, June 12, 2018, 18:20

35 circles of 14 mm diameter of cast #4 were packed into a graphite sample container.

30 x UO₂/C circles = 4.07 g

Graphite container mass = 5.3 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

Wednesday, June 13, 2018, 10:29 

Initial IGP1 = 6.43e-7 Torr

Tapped to 80A at 10A/10s with 20 s waiting period each 10 A

Waited 5 min for vacuum to stabilize.

Tapped to 90 A at 10A/10s with 20 s waiting period each 10 A

Waited 5 min to tap to 100 A 

Waited 14 min for vacuum to stabilize

Tapped to 400 A at 25A/30s with 30 s waiting period each 25 A

Tapped to 520 A at 20A/30s with 30 s waiting period each 20 A

Max pressure ~0.06 Torr 

Marla Cervantes wrote:

Tuesday, June 12, 2018, 18:20 35 circles of 14 mm diameter of cast #4 were packed into a graphite sample container. 30 x UO2/C circles = 4.07 g Graphite container mass = 5.3 g Graphite tube is placed inside a target boat. Boat previously coated with TaC and sintered. Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1. Chamber currently pumping down. Wednesday, June 13, 2018, 10:29  Initial IGP1 = 6.43e-7 Torr Tapped to 80A at 10A/10s with 20 s waiting period each 10 A Waited 5 min for vacuum to stabilize. Tapped to 90 A at 10A/10s with 20 s waiting period each 10 A Waited 5 min to tap to 100 A  Waited 14 min for vacuum to stabilize Tapped to 400 A at 25A/30s with 30 s waiting period each 25 A Tapped to 520 A at 20A/30s with 30 s waiting period each 20 A Max pressure ~0.06 Torr

 Wednesday, June 13, 2018, 11:08

Pressure was dropping indicating full carbothermal reduction but the current tripped off to 0 A.

Marla Cervantes wrote:

Marla Cervantes wrote:  Tuesday, June 12, 2018, 18:20 35 circles of 14 mm diameter of cast #4 were packed into a graphite sample container. 30 x UO2/C circles = 4.07 g Graphite container mass = 5.3 g Graphite tube is placed inside a target boat. Boat previously coated with TaC and sintered. Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1. Chamber currently pumping down. Wednesday, June 13, 2018, 10:29  Initial IGP1 = 6.43e-7 Torr Tapped to 80A at 10A/10s with 20 s waiting period each 10 A Waited 5 min for vacuum to stabilize. Tapped to 90 A at 10A/10s with 20 s waiting period each 10 A Waited 5 min to tap to 100 A  Waited 14 min for vacuum to stabilize Tapped to 400 A at 25A/30s with 30 s waiting period each 25 A Tapped to 520 A at 20A/30s with 30 s waiting period each 20 A Max pressure ~0.06 Torr   Wednesday, June 13, 2018, 11:08 Pressure was dropping indicating full carbothermal reduction but the current tripped off to 0 A.

 Wednesday, June 13, 2018, 12:23

The problem was reported to controls group

After 1 hour at 0 A, the autoramp was set to 4 A/min up to 520 A

The current and voltage are increasing accordingly.

The material will stay 4 hours at max point.

Thursday, June 14, 2018, 09:14 

After 4 hours the auto ramp was set to -1A/min to 0 A

Thursday, June 14, 2018, 14:47 

The IEVAP  was vented with Ar and the UCx was trasnferred to the glove box.

 Friday, June 15, 2018, 16:39

35 circles of 14 mm diameter of cast #3 were packed into a graphite sample container.

35 x UO₂/C circles = 4.07 g

Graphite container mass = 5.3 g

Graphite tube is placed inside a target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3 used Ta foils for heat shielding and the boat was installed in Evap1.

Chamber currently pumping down.

 Saturday, June 16, 2018, 15:00

Tapped to 80A at 10A/10s with 20 s waiting period each 10 A

Waited 5 min for vacuum to stabilize.

Tapped to 90 A at 10A/10s with 20 s waiting period each 10 A

Waited 14 min for vacuum to stabilize

Tapped to 100 A at 10A/10s with 20 s waiting period each 10 A

Tapped to 520 A at 20A/20s with 20 s waiting period each 20 A

 Tuesday, June 19, 2018, 15:51 

 The material will be in the evap for a week

Wednesday, June 27, 2018, 09:53 

 The IEVAP  was vented with Ar and the UCx was trasnferred to the glove box.

Wednesday, October 19, 2022, 10:27

Cartridge-220510Cx was installed in the EVAP1 and pumped down yesterday.

Material will be further conditioned at 450A for 4 hours.

The material will be conditioned inside a container tube with both ends open at the ends.  Two springs are inserted at the ends of the graphite cartridge to contain the material as graphite caps not inserted.

IGP1 = 7.8e-07 Torr

Good vacuum = 5e-4 Torr

Bad vacuum = 5e-2 Torr

Will autoramp @2A/30s (4A/min) to 40 A and then to 120A.  Fast ramp rate because material had previously been conditioned

Wednesday, October 19, 2022, 12:23

TGHT 450A, 5.2 V

Will leave for 4 hours and then begin ramp-down.

Wednesday, October 19, 2022, 16:21

IGP1= 3.1e-06Torr

450A, 5.2V

Start rampdown @- 2A/min

Thursday, October 20, 2022, 09:23

IGP1= 4.6e-7 Torr

 Thursday, November 22, 2018, 17:25

D-shaped discs were cut from cast #26

A 13mm punch was used to punch out discs from pre-cut strips

The target consists of 236 discs of 10 cm in length - all single discs, no packs.

236 x UO₂/C discs = 22.66 g

Graphite insert with caps = 11.74 g

The loaded inser is placed on target boat.

Boat previously coated with TaC and sintered.

Ta-target boat is wrapped with 3-layers (2 new one used) of heat shield and installed in evap1.

Chamber is pumping down.

 Friday, November 23, 2018, 08:53

Vacuum limits:

Good vacuum 1e-1 Torr

Bad vacuum 5e-1 Torr

IGP1 = 4.12 e-6 Torr

Current tapped manually to 100 A at 1A/s in 10 A blocks with a waiting period of 20 s between each increment.

Initial IGP1 = 5.31 e-6 Torr

Max  IGP1 = 0.066 Torr

Waited 20 min for pressure to rise and drop.

The current tripped off, when the 0.013 torr  (Fig. Nov23-CurrentTrip1).

Increasing the current to 100 A again.

IGP1 = 7.00e-5 Torr

Rate was increased to 25 A each 20 s until 200 A

The pressure increased and IV1 opened, current was dropped to 100 A

Pressure after 5 min 4e-4 Torr

Rate was increased again to 25 A each 20 s until 200 A

The current was reduced to 110 A because the pressure was rising to fast

Rate was increased again to 25 A each 20 s until 300 A

The automatic ramp was set to 20 A/ min from 0 to 300 A

The automatic ramp was changed to 10A/2min to 450 A

IGP1 = 2.15e-5 Torr

After 1.5 hour, the automatic ramp was set to 20 A/ min from 450 to 500 A

After 4hrs, the automatic ramp was set to -2 A/ min from 500 to 0 A