HQ Coil 18 Test Impregnation LARP Video Meeting November 21, 2013 Dan Cheng

HQ Coil 18 Status HQ Coil 18 was impregnated – Impregnation was designed to test the effect of trace lamination layer thicknesses – Used both.001” and.002” additional Kapton layers on traces – Examined materials, and improved processing Also incorporated splice insulation changes Utilized new batch of CTD epoxy Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 2

Coil 18 Trace Prep Procedures Instrumentation Trace – Wipe down with alcohol – Rough up surfaces with Scothbrite pad – Wipe with Acetone, then alcohol – Tin solder pads Lamination layer – Wipe with alcohol – Rough up surface with Scotchbrite pad – Wipe down with acetone, alcohol Lamination – Apply.375” wide strip of Scotch VHB transfer tape down center – Apply lamination layer to trace (handled using gloves) – Cut VT slits (not done for this coil) – Perforate trace layers with hole pattern – Apply to coil – Solder connections (not performed) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 3

Trace Lamination Layer Layout Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 4 OL RE:.001” Kapton, Plain OL LE:.002” Kapton, Plain IL RE:.002” Kapton layer IL LE:.001” Kapton, B-Stage* * It is possible that earlier coils (11-14) might have used a.001” Kapton that had Scotch 2290 B-stage epoxy applied to one side (mat’l was not clearly labeled).

Coil Impregnation Coil pre-heated to 60°C and pumped down overnight – Pressure based out <10 mTorr Epoxy mixed and preheated to 50-60°C – De-gassed to 300 mTorr Epoxy fill; takes approximately 2 hours – Fixture vacuum increased to ~1000 mTorr Cycle vacuum to atmospheric pressure 1x to 2x Soak under vacuum overnight * Bring chamber and fixture up to atmospheric pressure Start cure cycle Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 5 * Did not perform, due to a small (~7 drips/min.) leak in the mold while under vacuum

IL RE (.002” Kapton) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation6

OL RE (.001” Kapton, Plain) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation7 Perforations

IL Center (.001” -.002” Transition) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 8 Perforations Transition

OL Center (.002” -.001” Transition) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 9 Perforations Transition

IL LE (.001” Kapton, B-Stage) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation10 Perforations

OL LE (.002” Kapton) Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation11 Perforations

RE Endshoe Coverage IL (.002” Kapton) Very good wetting OL (.001” Kapton, plain) Very good wetting Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation12

LE Endshoe Coverage IL (.001” Kapton, B-stage) Virtually unwetted OL (.002” Kapton) Very good wetting Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation13

Coil 18 Trace Layer Performance Summary.002” inner layer RE looks good – Soak time and material adequate – Endshoe coverage is excellent.001” outer layer RE is “okay” – Soak time may not be adequate – Endshoe coverage is excellent Irregular surface over coil possibly affects ability to fill.001” inner layer LE does not look good – Soak time not be adequate; material questionable – Endshoe coverage is not good B-stage epoxy layer possibly prevents wetting.002” outer layer LE does not look good – Soak time not adequate – But endshoe coverage is excellent Irregular surface over coil needs more time to fill Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 14

Trace Lamination Conclusions.002” Kapton backing appears to fill trace layers better—if given enough soak time over irregular surface areas.001” Kapton seems to suffer from the effects of irregular surfaces that prevent complete filling.001” Kapton with B-stage seems to prevent wetting of trace layers with epoxy—even extended soak times may not have been adequate These conclusions support our experiences with HQ coils (impregnated with.002” Kapton layers) These conclusions also also seem to support our experiences with the use of.001” layers – HQ01-type: Examined in detail Coils 11 & 14 – HQ03-type: Coils so far observed same behavior Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 15

Additional Slides Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 16

HQ Coil 22 Status HQ Coil 22 has arrived from BNL – OL trace shows same lack of fill between trace layers as Coil 23 did SG bonding/installation is on hold until we examine issues in prior magnets/coils (recent LQ/HQ) Can be CMM’d while we wait Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 17

Coil 22, As Received Outer layer, REOuter layer, LE Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation18

Coil 22, As Received Inner layer, REInner layer, LE Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation19

HQ Coil 23 Status SG bonding/installation – Was completed before decision to examine SG installation – Wiring is currently incomplete All processes currently on hold Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 20

HQ Coil 25 Status Reaction fixture has been opened – All VTs show continuity, none lost Impregnation preparations on hold Nov 21, 2013 D. Cheng - HQ Coil 18 Test Impregnation 21