All-metal joints studies related to the mechanical and irradiation Przemyslaw Lutkiewicz Supervisors: Christian Rathjen, CERN Cedric Garion, CERN Blazej Skoczen, CUT

“All metal joints studies related to the mechanical and irradiation load” Przemyslaw Lutkiewicz AT/VAC

ConFlat joint Przemyslaw Lutkiewicz AT/VAC CLIC joint particle beam flow material under mechanical load and radiation Mechanical load

ConFlat join setup ConFlat joint concept Przemyslaw Lutkiewicz AT/VAC

Przemyslaw Lutkiewicz AT/VAC ; Fig. 9. Anisotropic model: a; Distribution of micro-damage (D11, D22, and D33) compared to evolution of plastic strain intensity (EPSE), b; Evolution of micro-damage components as a function of depth Fig. 4. Damage parameter D and elastic unloading modulus E as a function of strain at 4.2 K

Sealing force evolution Przemyslaw Lutkiewicz AT/VAC FE calculations experiments

Sealing force evolution Przemyslaw Lutkiewicz AT/VAC

Locating pins Experiment setup

Leak rate evolutionTightness during compression Przemyslaw Lutkiewicz AT/VAC

Przemyslaw Lutkiewicz AT/VAC ;

CLIC gasket vs 2 CHF coin Joint concept Drawbacks (things to be improved): Large and non constant displacements into gasket aperture (0.25 mm = ¼ of the gasket thickness) Different contact pressure distribution for upper and lower surface of the gasket Trapped volume and grove weakness 0.25 Lateral profile of the maximum inner displacements Contact pressure between upper gasket surface and flange Contact pressure between lower gasket surface and flange No sealing Sealing No sealing Sealing Contact pressure between upper gasket surface and flange No sealing Sealing Trapped volume Contact pressure near grove No sealingSealingNo sealing Sealing

Symmetry Existing design concept Przemyslaw Lutkiewicz AT/VAC gasket flange gasket flange New CLIC design concept

 Homogeneous contact pressure – the joint is symmetric type (sexless) Przemyslaw Lutkiewicz AT/VAC ;  Cheaper production – simple and easy to machine gasket shape and one type of flange  Easier assembly – symmetric, self-placed gasket with additional pins centering joint system  Superior RF properties – smooth flange-gasket-flange transition SYMMETRY NO SYMMETRY New proposalOld design 2) 3) 1) 2) 1)Female flange 2) Gasket with moderate shape 3) Male flange 1)One type of flange 2) Gasket with simple shape self-placed gasket self-placed gasket + Pins centering joint system 0.25 mm 0.15 mm Flange Gasket > 0.1 mm Flange Gasket

Przemyslaw Lutkiewicz AT/VAC Theoretical leak rate Total leak rate Collar interaction Thickness [mm] Imprint depth [mm] Alpha [deg] Beta [deg] Initial position [mm] Initial values Yes Final valuesNo Alpha (Q 1 ) Beta (Q 2 ) Gasket thickness Initial position

Przemyslaw Lutkiewicz AT/VAC Q1Q1 Q2Q2 collar interaction no collar interaction

Przemyslaw Lutkiewicz AT/VAC Displacement into the aperture

Przemyslaw Lutkiewicz AT/VAC Pressure distribution through the gasket circumferance

Przemyslaw Lutkiewicz AT/VAC ; The leak tightness level Joint at the experiment

Przemyslaw Lutkiewicz AT/VAC

Non Ionizing Energy Loss profile Przemyslaw Lutkiewicz AT/VAC

1 MeV neutron equivalent flow.

Tensile tests results for different irradiation dose [dpa] Przemyslaw Lutkiewicz AT/VAC

Orowan mechanism Przemyslaw Lutkiewicz AT/VAC Irradiation defects Hardening as a [dpa] dose function

Offset in the material properties at true stress- true strain space Przemyslaw Lutkiewicz AT/VAC

Representative Volume Element AsAs Mechanical load ADAD Elastic modules changes for OFS copper Przemyslaw Lutkiewicz AT/VAC

particle beam flow material under mechanical load and radiation Mechanical load Przemyslaw Lutkiewicz AT/VAC Irradiation influence on the material structure

SRIM calculation (Monte-Carlo method) micro-voids cluster formation Micro-voids cluster Przemyslaw Lutkiewicz AT/VAC

Mechanical damage for irradiated CF gasket Post-irradiation damage for irradiated CF gasket

Przemyslaw Lutkiewicz AT/VAC Post-irradiation damage evolution for different [dpa] values

Przemyslaw Lutkiewicz AT/VAC Results differences for different approaches

Przemyslaw Lutkiewicz AT/VAC

With width like old design With width like 1/3 of old design Przemyslaw Lutkiewicz AT/VAC