Production of magnetic bearings for motor and linear levitation applications

In this study, cylindrical and square YBCO samples were produced by the TSMG method. For YBCO production, Nd1.8Ba2.4Cu3.4O7 seed, Y123 and Y211 powders (Y123 75%, Y211 25%) were produced. CeO2 was added to the total mixture at a rate of 0.5% by weight and the resulting powder mixture was subjected to heat treatment. For the production of superconducting magnetic bearings; 20 mm diameter cylinders and 27 × 27 mm2 large square YBCO samples were produced. The edges of the cylindrical samples were shaped to obtain small square samples of 13.5 × 13.5 mm2. A rectangular superconducting magnetic bearing of 13.5 × 27 mm2 was formed by combining the small square samples, and a square magnetic bearing of 27 × 27 mm2 was formed by combining four small squares. Vertical magnetic force (Fz) – vertical motion (z) and horizontal magnetic force (Fx) – horizontal motion (x) were measured for all samples under ZFC and FC cooling conditions at 77 K. A two-dimensional numerical model based on the H-formulation was created using COMSOL Multiphysics 6.0. The two-dimensional numerical model agrees with the experimental results by 97%.