IEC TR 62331:2005

FOREWORD
INTRODUCTION
1 Scope and object
2 Normative references
3 Pulsed field magnetometer (PFM)
  3.1 General principles
  3.2 Size of test specimen
4 Field generator
  4.1 General
  4.2 Power supply
  4.3 Magnetizing solenoid
5 Polarization and magnetic field strength sensors (pick-up coils)
  5.1 General
  5.2 The polarization sensor (J coil)
  5.3 The magnetic field strength sensor (H coil)
6 Transient instrumentation and digitizing hardware
  6.1 General
  6.2 Analogue integration and digitization
  6.3 Digitization and numerical integration
  6.4 Digitization rate
7 Data processing
  7.1 Data processing elements
  7.2 Temperature
  7.3 Magnetic viscosity
  7.4 Calibration
8 Comparison of measurements
  8.1 Permeameter, "large magnet" comparison
  8.2 Extraction method, "small" test specimen comparison
  8.3 Comparative measurement conclusions
9 Conclusion
Bibliography

Reviews methods for measuring magnetically hard materials using pulsed field magnetometers. The methods of measurement of the magnetic properties of magnetically hard materials have been specified in IEC 60404-5 for closed magnetic circuits and in IEC 60404-7 for open magnetic circuits. The measurement result of the magnetic properties of magnetically hard materials at elevated temperatures is given in IEC 61807. Pulsed field magnetometers have been developed to provide rapid measurement facilities to match high speed production rates with 100 % quality control. The object of this report is to describe the principles and practical implications of pulsed field magnetometry in order to enable the full potential of the technique to be considered, including its application using small and large magnets of varying geometries, to various magnetic field strengths and frequencies.