Overview
IEC TR 61807:1999 is a technical report published by the International Electrotechnical Commission (IEC) that specifies methods for measuring the magnetic properties of magnetically hard materials (permanent magnet materials) at elevated temperatures. Magnetically hard materials, which include permanent magnets, are classified under IEC 60404-1, and their essential magnetic properties are detailed in IEC 60404-8-1. While previous standards such as IEC 60404-5 and IEC 60404-7 cover measurements at room temperature for closed and open magnetic circuits respectively, the current report addresses the increasing need to characterize these materials under elevated temperature conditions.
This standard is critical for applications where permanent magnets operate over a wide temperature range, ensuring consistent performance and reliability by specifying measurement techniques and temperature-dependent magnetic property coefficients such as remanence and coercivity.
Key Topics
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Scope and Purpose
Establishes measurement procedures for magnetic properties of magnetically hard materials at elevated temperatures extending beyond room temperature.
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Magnetic Properties Covered
- Maximum magnetic energy product ((BH)_max)
- Remanence (B_r)
- B-coercivity (H_cB)
- J-coercivity (H_cJ)
- Recoil permeability (µ_rec)
- Density
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Temperature Coefficients
Specifies temperature coefficients for remanence (or saturation) and J-coercivity to quantitatively assess material behavior under thermal stress.
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Measurement Methods
Standardizes testing methods applicable to different types of magnetic circuits (closed and open), utilizing equipment and procedures adapted for high-temperature environments.
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Evaluation and Reporting
Includes guidelines for data evaluation, test reporting, and examples of calculations to aid in precise interpretation of measurement results.
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Material Review
Provides an overview of existing magnetically hard materials, such as anisotropic sintered NdFeB and Sr-ferrite magnets, highlighting behavioral characteristics at elevated temperatures.
Applications
The standard IEC TR 61807:1999 is essential for industries and sectors where permanent magnets must maintain functionality at high temperatures, including:
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Automotive Industry
Electrified vehicles and motor systems where magnets are exposed to elevated operating temperatures.
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Aerospace and Defense
Components subjected to harsh thermal environments requiring high reliability.
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Renewable Energy
Wind turbines and other electric generators where magnetic materials face varying temperature conditions during operation.
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Industrial Motors and Sensors
Devices operating in elevated temperature industrial settings demand accurate magnetic property evaluations for design optimization.
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Consumer Electronics
Ensures performance stability of magnetic components in devices that experience temperature variation.
Related Standards
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IEC 60404-1
Classification of magnetic materials, foundational for understanding permanent magnet categories.
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IEC 60404-5
Measurement of magnetic properties of magnetically hard materials at room temperature for closed magnetic circuits.
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IEC 60404-7
Specifies the measurement method of coercive force in open magnetic circuits at room temperature.
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IEC 60404-8-1
Specifies magnetic property requirements and temperature coefficients for magnetically hard materials.
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IEC 60050 Series
International Electrotechnical Vocabulary (IEV), providing standardized terminology related to electromagnetism and magnetic materials.
Keywords: IEC TR 61807, magnetic properties, magnetically hard materials, permanent magnets, elevated temperature measurement, temperature coefficients, remanence, coercivity, magnetic energy product, magnet measurement methods, IEC magnetic standards.