Hirst offer a number of magnet characterisation systems as described below:-
The most basic is the Helmholtz coil and fluxmeter, this is good for incoming magnet inspection and provides a way to measure some of the properties of the magnet, including Br, Total magnet moment and estimating HcB. The Helmholtz system can also ensure pre-magnetised magnets are of the correct strength.
Hirst also offer permeameter based systems, this is where a magnet is exposed to an applied field and its response measured. In this system Steel/Iron pole pieces are used to concentrate the magnetic field and while the permeameter can extract the vast majority of useful magnet parameters it has fundamental limitations and cannot fully measure (at room or even moderate temperatures) many of the high grade NdFeB and SmCo types of magnets that are increasingly common. Shapes and sizes of samples are also some what limited. This is a fundamental limitation of the steel “closed circuit” system.
Hirst also offer pulsed field magnetometers. Hirst has been instrumental in the development and standardisation of this type of equipment since the 1980s. It offers the ability to measure any magnetic material, no matter the grade and it does not also suffer the shape issue that the permeameter has. Options to control sample temperature from -40 to +220 degrees C are also available.
For more information please see the types of equipment below :-