High energy magnet
That's how horse shoe magnets look like at the University of Karlsruhe!
Online since: 20/05/2011, Number of visits: 94203
A high energy magnet made out of 8 COLOSSI:A magnet with pole shoes and yoke made of iron. The 8 COLOSSUS magnets (Q-40-40-20-N) can be seen under the holding frame made of aluminium. In a 1,5 mm high slot and an area of 1 cm2 there is a field of 3,2 Tesla. Measuring this field was not easy because there are only few probes on the market that are thin enough and can still measure such a strong field at room temperature. That's why we build the probe ourselves and calibrated it with a calibration magnet.
This magnet is now used for the testing of particle physics detecting components.
COLOSSUS (N42) have been used instead of DEATH MAGNETS, because they have a slightly higher remanence and therefore energy density.
Mounting the magnets was not easy: magnets of the same polarity placed next to each other tend to repulse each other sideways. In this case we had to use vices and a frame made of aluminium to get the magnets side by side.
All the surfaces were grinded flat and smooth to transport the magnetic field undisturbed by air gaps. After the construction was completed it had to be disassembled again to decrease the distance between the pole shoes. That could not be done by hand and a winch was deployed. The force needed was an estimated 1960 N. Unfortunately there are no pictures of this undertaking.
Here you can see the simulation of the magnet with field lines and field distribution. In the simulation 'only' 2,8 Tesla are reached. But the simulation assumes a 2D situation. This means it simulates a magnet with pole shoes in the form of a roof. In Reality the field lines are compressed on all four sides (like a pyramid), and that's why the values are actually higher.