IEC 60404-18:2025 defines the general principle and technical details of the methods of measurement of the DC magnetic properties of permanent magnet materials in an open magnetic circuit using a superconducting magnet (SCM).
This method is applicable to permanent magnet materials, such as those specified in IEC 60404？8？1, the properties of which are presumed homogeneous throughout their volume.
There are two methods:
- the SCM-vibrating sample magnetometer (VSM) method;
- the SCM-extraction method.
This document also specifies methods to correct the influence of the self-demagnetizing field in the test specimen on the demagnetization curve obtained in an open magnetic circuit. The magnetic properties are determined from the corrected demagnetization curve.