The choice of magnetic material is based on a number of
magnetic properties, such as, energy density ((BH)max),
remanence of permanent magnet (Br), coercivity (Hc),
material’s volumetric mass density and temperature in
which the magnet can keep its above parameters effectively.
From our study, the magnetic material chosen for the
designed magnetic expander can be NdFeB (Neodymium-
Iron-Boron) which has higher energy density compared to
most other available materials (theoretical maximum energy
density of NdFeB is 485 kJ/m3)