Mechanical properties of Gd123 bulk superconductor at liquid nitrogen temperature

In order to investigate the mechanical properties of the Gd123 single grain bulk superconductor at low temperature, bending tests were carried out. The bending fracture strength at LNT (liquid nitrogen temperature) scattered from 83 to 120 MPa was higher than that at RT, from 62 to 86 MPa. However, the Young´s modulus at LNT scattered from 109 to 123 GPa was comparable to that at RT, from 110 to 129 GPa. The Weibull coefficient for the bending strength at LNT, 6.5, was almost identical with that at RT, 6.9. The endurance limit for the repeated pulsating bending up to the5 × 10⁴ cycles at LNT, 70 MPa, was about 70% of the average value of the monotonic bending strength.