Elastic Modulus Measurements of the LHC Dipole Superconducting Coil at 300 K and at 77 K

We present measurements of the stress-displacement relation for the superconducting coils used in the Large Hadron Collider main magnets (dipoles and quadrupoles). This mechanical property is relevant to determine the correct amount of azimuthal pre-stress to be imposed on the coil. The hysteresis pattern in the loading and unloading curves is discussed. The stress-displacement curves are used to compute the corresponding elastic moduli and deformations. Measurements are also carried out at liquid nitrogen temperature, using the same framework to interpret experimental data.