Some Recent BNL, LBNL and Yale Work 1.Honeycomb flatness from manufacturer 2.Commercially fabricated C-channel 3.VCR Fittings 4.BN powder thermal evaluations 5.Facing sample for electrical contact 1 D. Lynn, Local Support Vidyo Meeting Jan

Honeycomb Flatness Along with DESY and Liverpool BNL placed common order for new vented honeycomb BNL would like to investigate possibility to avoid grinding honeycomb. Need tighter tolerance on flatness. So BNL ordered two slices with tighter tolerance with of cost increase of about 6%. 2

Honeycomb Flatness Ultracor gives the following conformance data. Measurements at 6 locations per slice. All measurements were within specification 3

Honeycomb Flatness Spacing was 4” by 3” Tolerance on both sheets within +/-.002” (50 um) Can UK and DESY measure theirs? Unfortunately all honeycomb slices were deliberately oversized at 5.5 mm (to grind to 5.2 mm). Do we make a slightly thicker stave to test concept? To compare, BNL made 35 measurements per slide in a grid pattern as shown below. 4

Carbon Fiber C-Channels as Received from Allred/Dragonplate 4 December, 2014 W. Emmet/T. Hurteau Yale University Physics Department 5

Commercial C-channel 150 gsm-34 msi (aka 234 GPA)—700k tensile. 35% resin (Newport 301) 6

End view Note: this is untrimmed, machining end will clean this up 7

Slight ridge at inside radius… tooling? View of channel interior (legs facing camera) 8

View of channel side 1 9

View of channel exterior (legs facing away from camera) Slight ridge here… tooling again? 10

View of channel side 2 11

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Commercial C-channel Wall thickness E, F, G not the same, but uniform on each wall Large bow Will discuss with Dragon plate possible improvements Will try to irradiate parts with 25 MeV protons at Karlsruhe (pre/post bend test) 13

Yale Brazing 14

Yale Brazing Recipe 15 Basically DESY recipe Braze material: Wieland SCP-1 (68% Ag/5.0% Pd/26.6% Cu) Brazed in vacuum furnace Procedure: Vacuum at mBar Ramp up to 750 o C over 2 hours Hold for 8 minutes at 750 o C Ramp up to 820 o C over ~30 minutes Turn off heat and allow to cool down under vacuum (take several hours) Whole process takes about a day Sample also brazed at Solar Industries using same recipe

Yale SS VCR to Ti Pipe Brazing 1A1B 2A2B 16

Solar SS VCR to Ti Pipe Brazing 1A1B 2A2B 17

First samples of Yale and Solar brazing had VCR fitting bore diameter about thousandths larger the Ti pipe. Solar says want almost pressure fit to get a fillet Both Yale and Solar samples were hydro pressure tested to 3500 PSI (~230 bar) for one day and showed no signs of leaking, i.e. no pressure change Sent second small sample to Solar Industries; has approximately 0.5 thousandths larger diameter. Full length Titanium tube will be vacuum brazed at Solar Industries following inspection/hydro pressure test of the second sample’s tighter-fitting VCR- titanium joints. 18 Titanium VCR Fittings

19 Titanium VCR Fittings At Sep 2014 ITK meeting Richard French asked us to look into whether Swagelok would make Titanium VCR fittings. In principle should be easier to braze to Titanium pipe. He was having difficulty with Swagelok contacts in the UK. Will Emmet got first quote for Ti blind gland (we prefer blind gland so that we can drill gland to accommodate different diameter Ti pipes in case that dimension changes First quote was for $466/each (similar to what Richard was getting). Will used old contact to get quote down to $52 each. We have ordered a quantity of week delivery.

20 BN powder study Carl had mentioned they have access to an expensive machine that is designed to measure thermal conductivity; sorry, I don’t have the details at the moment. We decided it would be a good opportunity to use machine to compare the different BN powders currently in use. Graham also want to compare thermal conductivity with his device. Use 10%, 20%, and 30% BN powder (by weight). BNL/Yale: ZYP UK: Goodfellows DESY: PT140 (but we also obtained PT180…different particle size)

BN powder study, sample list 21

22 BN powder study Samples to ship week of Jan 26 th

23 Electrical Aspects of CF Facings Want to test transverse and vertical electrical connectivity Want to test co-cured foil to facing electrical connectivity

24 Samples Made at LBNL; testing to start soon (quick test showed good DC connection of foil to fibers