Thermomechanical behaviour of Nb3Sn magnet constituent materials

Tuesday 26 May 2020, 14:00 → 15:00 Europe/Zurich

https://vidyoportal.cern.ch/join/4JiI2jRNys (CERN)

Christian Scheuerlein (CERN)

Please note that the we kindly ask you when connecting to this seminar to mute your microphones and cameras in order to have a good connection.

 

Abstract

Reliable mechanical materials data is required for predicting the strain and stress state evolution during assembly, thermal cycling and powering of superconducting magnets. In the first part of the seminar, the ingredients for the thermomechanical modelling of linear elastic and isotropic magnet materials behaviour are presented. Different characterisation methods and their experimental uncertainties are compared. The additional challenges caused by anisotropic mechanical properties, the yielding and flowing of fully annealed Cu, the brittle Nb3Sn, and the non-linear and irreversible thermal expansion of the Nb3Sn conductor are addressed. The Nb3Sn conductor block Young’s modulus anisotropy and mechanical behaviour are explained based on neutron diffraction loading strain and stress measurements. It is shown that the conductor block behaves like a fibre reinforced composite, with iso-strain and iso-stress in the conductor constituents under axial and transverse loading, respectively. The potential of different coil characterisation methods, notably digital image analysis and indentation hardness maps in metallographic coil cross sections, and residual strain mapping of collared coil assemblies by neutron diffraction, are compared

 

VIDYO room : https://vidyoportal.cern.ch/join/4JiI2jRNys

Nb3Sn-magnet-materials-MSC-seminar-26May2020-final.pdf

Nb3Sn-magnet-materials-MSC-seminar-26May2020-final.pptx