IEC 60404-18:2025

Overview

IEC 60404-18:2025 is an international standard published by the International Electrotechnical Commission (IEC) that defines the methods for measuring the DC magnetic properties of permanent magnet (magnetically hard) materials. This standard focuses on measurements in an open magnetic circuit using a superconducting magnet (SCM). It applies specifically to permanent magnet materials with homogeneous magnetic properties throughout their volume, such as those referenced in IEC 60404-8-1.

The standard introduces two primary measurement techniques:

• SCM-vibrating sample magnetometer (VSM) method
• SCM-extraction method

Additionally, IEC 60404-18:2025 specifies methodologies for correcting the influence of self-demagnetizing fields on the demagnetization curve, ensuring accurate determination of magnetic properties from corrected measurements.

Key Topics

Measurement Principles

• Open Magnetic Circuit Measurement: Techniques are designed for analyzing magnetic properties without a closed magnetic loop.
• Superconducting Magnet Usage: Employing SCM enables high-precision magnetic field application and measurement.
• Magnetic Dipole Moment and Field Sensing: Utilizes sensitive coils and sensors to determine magnetic polarization and field strength.

Methods of Measurement

• SCM-VSM Method: Vibrating the specimen within the superconducting magnet to measure its magnetic dipole moment.
• SCM-Extraction Method: Moving the specimen to extract magnetic signals for analysis.

Demagnetizing Field Correction

• Correction Approaches:
  • Method A: Uses shape-based demagnetizing factors.
  • Method B: Considers both specimen shape and magnetic susceptibility.
  • Method C: Applies inverse analysis accounting for spatial self-demagnetizing field distribution.

These corrections are critical for accurately plotting demagnetization curves and deriving magnetic parameters like remanent magnetization and coercivity.

Determination of Magnetic Properties

• Remanent Magnetic Polarization (Jr)
• Maximum Energy Product ((BH)max)
• Coercivity (HcJ and HcB)

Applications

IEC 60404-18:2025 is essential for researchers, engineers, and manufacturers working with permanent magnet materials, especially in the fields of:

• Magnet Design and Development: Accurate magnetic property data supports the design of optimized permanent magnets for motors, generators, sensors, and actuators.
• Quality Control and Testing: Standardized measurement methods ensure reliable and reproducible characterization of magnetic materials during production.
• Scientific Research: Provides precise methodologies for fundamental magnetic property investigations in laboratories.
• Magnetic Material Certification: Enables compliance with international standards for permanent magnet materials used in critical industrial applications.

Related Standards

• IEC 60404-8-1: Defines classifications and specifications for permanent magnet materials, referenced directly in IEC 60404-18.
• IEC 60404 Series: The broader series dealing with magnetic materials, including testing and classification.
• ISO/IEC Directives: Guidelines followed in the drafting and development of IEC 60404-18 to ensure consistency across international standards.

Practical Value

By standardizing sophisticated measurement methods employing superconducting magnets, IEC 60404-18:2025 enhances measurement accuracy of magnetic properties critical to permanent magnet performance. This facilitates:

• Detection and correction of demagnetizing effects ensuring objective property evaluation.
• Uniformity in test procedures globally, fostering consistency in magnetic materials quality.
• Enabling cutting-edge research and industrial innovation through reliable magnetic characterization tools.

For professionals involved in magnetic materials testing or development, adherence to IEC 60404-18 ensures high-confidence data acquisition aligned with international best practices, supporting both product development and quality assurance endeavors.