Cooled Carbon Support BTeV Pixel Detectors

1
Cooled Carbon Support BTeV Pixel Detectors

• Development Recommendations for 2001
• T R Knowles
• 3/7/01

2
FY00 Progress

• Cooled carbon structure demo articles
  (full-scale)
• Lightweight
• Rigid
• Shingled surface
• Porous chip mount
• Al manifolds
• Issues
• Resistance at tube wall
• Toughness and leak-tightness

Fibrous surface for shingling with high contact
conductance Vertical high-k fibers with in-plane
discrete fiber reinforcements Tubes cemented in
grooves
3
FY01 Recommendations

• Improve tube-matrix thermal interface using
• Radial high-k carbon fiber fintubing
• Machined and assembled into array
• Compatible with in-plane reinforcements
• Improve hermetic reliability using
• Fiber reinforced stress relief at tube/manifold
  joint
• Monitor leak-tightness throughout processing
• Investigate carbon manifolding using
• Graphite tube with pyrocarbon seal

4
Graphite Header Tubing

• Sealed POCO graphite tube
• Tube machined from POCO
• Pyrocarbon CVD seal coat
• Helium leak test
• Light CVD seal reduced He permeation to lt5e-9
  mL/s (most sensitive scale on leak detector)
• Expect heavier coat to seal even better (no
  helium leak signal)
• Good candidate for headers
• May reinforce with carbon braid to improve
  strength and toughness

5
Tube Manifolding

• Carbon carbon construction
• Tubular elements
• Large-gauge headers
• Small-gauge lines
• Carbon joining
• Carbonize bonding resin
• Seal by pyrocarbon CVD
• Reinforcement options
• Integral boss on graphite header for larger
  tube/header interface
• Fabric reinforcements