Overview
IEC 60404-5:2015 - "Magnetic materials - Part 5: Permanent magnet (magnetically hard) materials - Methods of measurement of magnetic properties" specifies standardized laboratory methods to measure the magnetic behavior of permanent magnet materials. The standard defines how to determine magnetic flux density (B), magnetic polarization (J) and magnetic field strength (H), and how to obtain the demagnetization curve, recoil line and principal characteristics such as remanence, coercivity and the maximum (BH) product. The 2015 edition updates measurement procedures for modern high-coercivity materials and tighter temperature control.
Key topics and technical requirements
- Measurement targets: B(H) and J(H) hysteresis loops, demagnetization curve, recoil line, remanent flux density (Br), intrinsic coercivity (HcJ) and coercivity relating to flux density (HcB), and (BH)max.
- Adaptation for high-coercivity materials: Procedures and test conditions extended to support magnetically hard materials with HcJ > 2 MA/m (important for modern NdFeB grades).
- Temperature control: Recommended ambient/test temperature tightened (previously 23 ±5 °C) to ±1 °C or better for materials with large temperature coefficients; updated temperature conditions to measure high-temperature-coefficient materials.
- Test setup: Measurements are carried out in a closed magnetic circuit (electromagnet + test specimen) to simulate ring-like conditions. Requirements cover electromagnet design, pole-face geometry, air-gap minimization and search-coil/measurement circuitry.
- Specimen geometry & reproducibility: Defined specimen dimensions, air-gap influence (Annex A), reproducibility metrics and required content for the test report.
- Reporting: Standardized test report elements to ensure comparable, traceable results.
Practical applications and users
IEC 60404-5:2015 is essential for:
- Permanent magnet manufacturers validating material performance and production consistency.
- Independent test laboratories performing certified magnetic property measurements.
- Motor, generator and actuator designers (especially in EV/HEV applications) who need accurate magnet parameters (Br, HcJ, (BH)max) for magnetic circuit design and simulation.
- R&D teams developing new high-coercivity or temperature-stable magnetic alloys.
- Quality assurance and procurement functions that require standardized test data for material acceptance.
Using this standard improves comparability of magnetic data, supports reliable magnetic circuit design, and ensures measurement practices keep pace with advanced magnet materials.
Related standards
- IEC 60404 series (other parts on magnetic materials)
- IEC 60404-8-1 (materials classification referenced)
- IEC TR 61807 and IEC TR 62331 (technical reports referenced for high-coercivity and elevated-temperature measurements)
Open preview (PDF)Magnetic materials - Part 5: Permanent magnet (magnetically hard) materials - Methods of measurement of magnetic properties
