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Message ID: 155     Entry time: Thursday, September 11, 2014, 14:23
Author: Laura Lambert 
Target Material:  
Target Oven W.O#: 40282-3 
Source: TARGET BOAT 
Status: Failed 
Subject: Sintering TaC coated end caps 

 Thursday, September 11, 2014, 13:14

The target container end caps were coated with TaC spray and let dry.

The caps are inserted in the target boat wrapped in graphite foil with 3 x Ta-heat shields.

The chamber is currently pumping down.


 Friday, September 12, 2014, 14:17

Chamber was pumped down overnight.

HS cooling water valves opened, no leaks detected.

IGP1 = 7.2e-7 Torr.

TGHT stepped up to 35A, TBHT at 0A.

Waited ~30min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min.

Will ramp TGHT to 580A with a max 10V.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.


 Monday, September 15, 2014, 11:31

TGHT stopped at 500A due to not high enough voltage max.

Increased max voltage to 12V


 Monday, September 15, 2014, 14:17

IGP1 = 6.3e-7 Torr

Increasing ramping rate to 1.0A/min


 Tuesday, September 16, 2014, 09:04

TGHT reached 577A and finished auto-ramping, then proceeded to drop down to 560A overnight.

Increased max voltage to 13.05A and TGHT to 580A.


 Tuesday, September 16, 2014, 13:52

TGHT reached 580A and sat there for ~5hrs.

IGP1 = 6.1e-7 Torr.

Initiating auto-cool at 2.0A/min.


 Wednesday, September 17, 2014, 13:03

Vented in air.

Opened up....looked 'deceivingly' ok.

then i took a layer of Ta off....grrrr  

the 1st layer of Ta was holding the boat together. as soon as that layer was taken off the target boat broke.

see attached photos.


 

Attachment 1: IMG_20140917_142605683.jpg  3.717 MB  Uploaded Wednesday, September 17, 2014, 15:53  | Show | Hide all
Attachment 2: IMG_20140917_143120141.jpg  3.413 MB  Uploaded Wednesday, September 17, 2014, 15:53  | Show | Hide all
Attachment 3: IMG_20140917_143343399_HDR.jpg  3.014 MB  Uploaded Wednesday, September 17, 2014, 15:53  | Show | Hide all
Attachment 4: Capture.JPG  84 kB  Uploaded Wednesday, September 17, 2014, 16:19  | Show | Hide all
Attachment 5: Capture2.JPG  72 kB  Uploaded Wednesday, September 17, 2014, 16:23  | Show | Hide all
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