Permanent Magnet Properties

Testing system testing and characterization of permanent magnets has a very high priority for permanent magnet properties in many industrial areas. Source: Pete Cashmore. Especially for sensory applications, the complete and uniform magnetization of permanent magnets for a stable functioning of the product plays a crucial role. However, most companies are dependent on quality assurances of their suppliers (mostly Chinese). To the chagrin of the engineers and quality assurance, the magnetic characteristics of permanent magnet can be, as record such as the angle of magnetization or the remanent magnetization with classic Hall measurement only with great effort. The M-axis test bench was developed out of necessity of valid registration and documentation of magnetic properties, discovered essential parameters such as magnetization, magnetization angle, as well as North/South effects for the application.

For magnet having a magnetic moment (mainly determined by volume and material of the test specimen) from 0.01 to 10 on the square, the free Remanence with maximum 1% tolerance, magnetization angle with maximum 0.2 tolerance, as well as the percentage North/South effect are recorded and filed in a database. In the M-axis application classification boundaries can be set, so a simplified input and quality control can be carried out. A rapid processing of larger quantities is also possible through short measuring times and ease of use. The chosen deliberately modular design of the system allows the measurement in the close field with Hall sensors, as well as in the far field using AMR sensors and a comfortable customer-specific extension of the measuring system. The M-axis system provides a test environment with the permanent magnets can be characterised very efficiently. The underlying the determination of magnetization process is based on the determination of dipole properties of dauermagnetischer materials. While the magnets, the magnetic moment and the direction of magnetization are determined in addition to the three-dimensional position.

In the comparison to the survey with Helmholtz coils is not the magnetic flux alteration on integrated however, but it is measure directly the induced magnetic field. The magnet must not be moved so during a measurement so that the pure measurement time in the range of less than 100 milliseconds. Still, the M-axis system very well in existing production and quality assurance processes can be integrated, the magnets to be processed can be tested without significant overhead.