Graham Beck, WP4 - 2nd Oct QA/QC of completed stave core: What test systems exist? Generally: QA tests are under discussion/development (slow but on-going!) Many are restricted to Room Temperature (and not irradiated). Electrical Tape robot (Oxford) LBNL/BNL(future) ? Geometry various CMMs. Mechanical Cooling tube pressure/leak tests ?? Integrity: Facing deformation at 5 psi (BNL ==> Iowa State) Stiffness: 3(4?)-point bend (Oxford, Liverpool?, BNL) Stability: ESPI set-up. Low T (CO 2 ) (Oxford) Thermal Thermal Cycling Chamber (QMUL “coffin”) Warm water/inert fluid (above dew-point) IR test (QMUL) Monophase + Chiller + IR Low T (BNL ==> Iowa State)

2 Laser Line Imaging Technique Use laser with multi laser line output to measure transverse height coordinate instantly. Use camera to record image. Convert image to profile information. Later use x-stage to step in longitudinal direction. Technique can in principle be faster than using a laser spot mapping a grid. Test Sample. FR4 Board with reference tokens mounted on top Reference tokens Graham Beck, WP4 - 2nd Oct.2015 pressurize core to 5 psi. Has pull tested tokens up to 9 psi (limit of tester) – no failures.

3 D.Lynn - Stavelet with built-in facing -honecomb faults (Feb 2015 ITk week)

4 BNL Thermal Imaging Setup. - Chiller provides hfe7100 at -30C. - Thermal load is provided by ambient. (Oct 2015): Awaiting BNL test re adequate flow rate through 2mm id x 2.8m tube. + vignetting, Narcissus effects. US QA effort shifting to Iowa State (Jim Cochran, Soeren Prell, Chunhui Chen, YU Jie, Carlos Vergel. - currently investigating IR cameras + software (FLIR A655sc, FLUKE TiX640)

Graham Beck 6 Feb WARM liquid: A potentially quick, first stage QC of thermal performance. e.g. hfe7100 at +40C (chiller). Q transfer to ambient ≈ 30% module heat. Simple set-up: no N 2 box, easy IR view Useful so far, flowing water (eventually must replace by hfe due to corrosion concern). Stitch-up of ~ 12 IR thermograms (each distorted due to ~20° viewing angle) US Stave250 (foam sealed with BN/Hysol, CGL joint) looked uniform UK Plank7 : unreliable joint between foam and pipe or facing? (3C wobbles, confirmed by TCs. Not seen on reverse face) camera was eventually tilted! Warm Coolant Study of Stave Core Performance (Graham Beck)

Graham Beck (QMUL) 17th Aug Stave Thermal QA – some other options Back burner: QMUL X-ray tomography (max 10 x 30cm, contrast?) Ultrasonic (negative experience at BNL, QMUL) Capacitive Tap Tester (Woodpecker) ? IR Thermal Static/Transient ?  To assess QA techniques need a stave(let) with built-in features: Missing glue facing-honeycomb Missing glue facing-foam Missing glue foam-pipe Extra glue sealing foam surface(as BNL)

Graham Beck (QMUL) 17th Aug Thermal transients in Plank7 ? -Pump 2 litre/minute water (fluid inlet at top, ≈ 0.5 seconds around loop) at RT(~24C) => initially, plank surface close to ambient. -Turn ON Lamp (275W ATLAS Reflector) -Watch with IR camera.

8 Surface T vs t[s] above cooling tube + final profile: Z = 13cm. Reasonable behaviour …

9 Z = 54cm. RHS part of tube ineffective here.…but can fault be located by analysing T(t) ? Expect difficult if facing-foam joint thermally close to foam-tube joint. Short or more localised IR pulse better? FEA might help.

Extracts from the (evolving) Stave QA doc: QA: Thermal contraction of pipe in stave Validation of foam-pipe glue joint (100um air gap => sensor at +20C !) 300 cycles between 25°C and -45°C at a rate of 1°C/s 30 cycles instantly from -35°C to -55°C. (re CO 2 leak). ESPI & stability measurements QC Mechanical Integrity: Facesheet to core delamination currently under study (see Appendix) include: ‘tap test’, ultrasonic testing. Pressurise Core + Laser surface profile... BNL..+ Fluid flow +Thermal Image (sensitive to facing → pipe conduction) … BNL Sonic excitation + Laser displacement..... LBNL Bus Tape Pad Inspection Check positions of bond-pad fields within (tbc) 0.25mm of nominal positions Fiducial Mark Inspection Clarify. Bus Tape Electrical Test - the automated test is possible on the completed stave – and should be repeated just prior to module mounting. Graham Beck, WP4 - 2nd Oct

(contd.) Cooling Tube Pressure Test - sub-set (?) of the sub-component Pressure Test (above) CMM Surveys: Flatness, Thickness and co-planarity Position of locking points and pins Thermal Cycling Test. A few cycles between room temperature and -40°C. TOLERANCE? Existing options: QMUL (“coffin”): custom-built chamber – uses convective exchange. BNL test box: Stave temperature controlled inert fluid circulated through the cooling pipe. (Minimum T ≈ -35C). Possibly (depending on availability, cost and capability): TRACI-2 CO 2 cooling system...followed by Delamination and Mechanical Stiffness checks. Need to specify requirements such as flatness, and stiffness (below). Stiffness Measurement 3-pt (4-point?) test => bending stiffness (dominates) and shear modulus. Tolerance? Resonance test: e.g. mechanical excitation + deflection measured by capacitive probes => resonance frequencies, damping for different modes. (possibly) Suspend the stave, hit with a computer controlled impulse hammer and measure decay in amplitude at a few places. FFT ‘finger-print’ to compare. Graham Beck, WP4 - 2nd Oct

(contd.) Thermal QC Flow + Temperature measurements to check integrity of the cooling path. Options under study include : Circulate chiller fluid above dew-point (hfe7100, CO 2 ?): capture IR image (semi-proven) Circulate chiller fluid (hfe7100) at -35C: capture IR image. Issues: Dew-point control / Flow rate / Chiller cost/ IR aberrations (accuracy)? (semi-proven) As above, flowing evaporative CO 2 : TRACI to be investigated. - all based on thermal load to/from ambient Is poor definition of flux from ambient also an issue here? Maybe not as long as consistent between tests/test sites? Immediately following mounting in Module Mounting Frame Check adhesion of module to core - prevailing uncertainty re SE4445: adhesion and shear requirements After Wire-bonding (each side) REQUIREMENTS? Need a QA for this! Graham Beck, WP4 - 2nd Oct

Graham Beck, WP4 - 2nd Oct Suggestion: investigate “automated tapping” J R TECHNOLOGY LIMITED: composite production, test and repair specialists (Royston) (Mitsui device) - Looked at QMUL X-ray CT (Graham Davis: spoke to him ~ 2000 re X-ray detectors): detects Fe-based ink on old scrolls: may be interesting long term, but note Richard Bates problem with contrast in X-ray of stave core sample.