Overview
IEC 60404-1:2016 - "Magnetic materials - Part 1: Classification" is an International Electrotechnical Commission (IEC) standard that defines a harmonized classification system for commercially available magnetic materials. The standard applies to materials used where ferromagnetic or ferrimagnetic properties are required and separates products into two principal groups based on coercivity:
- Soft magnetic materials (coercivity ≤ 1 000 A/m)
- Hard magnetic materials (coercivity > 1 000 A/m)
This 2016 edition emphasizes classification (what a material is) rather than specification (how it performs). Notable changes in this edition include removal of tables/values that described typical material properties to keep the document strictly a classification, adjustments to allowable compositional ranges for certain nickel- and cobalt-based classes, and the addition of a new bonded magnet class (bonded rare earth‑iron‑nitrogen, U5).
Key topics
- Classification scheme: Detailed class structure covering soft magnetic classes (A–J) and hard magnetic classes (Q–U), e.g., irons, low‑carbon steels, silicon steels, nickel‑iron and iron‑cobalt alloys, amorphous and nanocrystalline materials, hard ferrites, RE‑Fe‑B, AlNiCo and bonded magnet families.
- Coercivity threshold: The primary criterion separating soft and hard materials (1 kA/m).
- Chemical classing and subclassification: Materials are grouped by chemistry and processing route (bulk, flat, sintered, bonded).
- Forms and production methods: Identification of available product forms (strip, bulk, sintered, bonded) and relevant manufacturing routes (powder metallurgy, amorphous ribbon, nanocrystalline processing).
- Scope-focused content: The edition is focused on identification and class definitions rather than providing performance tables or specification limits.
Applications and users
IEC 60404-1 is useful to:
- Material manufacturers and suppliers for class labeling and product catalogs
- Design engineers specifying magnetic materials for transformers, inductors, motors, generators, sensors and actuators
- Procurement and standards teams to harmonize material terminology across contracts
- Test laboratories and certification bodies for material identification and reference
- R&D groups comparing material families (e.g., amorphous vs. nanocrystalline vs. ferrite vs. rare-earth magnets)
By using the standard, stakeholders ensure consistent naming and class-based selection of magnetic materials during design, purchasing and regulatory processes.
Related standards
IEC 60404-1 is the classification part of the IEC 60404 family. Other parts of the IEC 60404 series and related IEC documents address measurement methods, specifications, testing and application guidelines for magnetic materials and magnetic components. Use IEC 60404-1 for consistent terminology and class identification before consulting subsequent parts for test methods and performance specifications.
Keywords: IEC 60404-1, magnetic materials, classification, soft magnetic materials, hard magnetic materials, coercivity, bonded magnets, nickel‑iron, iron‑cobalt, rare‑earth magnets.
