When the magnet is used for maglev, will the magnetic force disappear soon?

Answer
The degree of magnetic force disappearance depends on the repulsive force of maglev. If only 50% of the repulsive force is used (assuming that the repulsive surface of two magnets is squeezed to 100% of the contact force), the magnetic force will not decline quickly. In addition, the speed of demagnetization depends on the magnetic retention of the magnets used.