Speaker
Description
Coercivity is not only one of the most fundamental properties of a soft magnetic material, but it is also very sensitive to structural changes of the material. Thus, since the introduction of the first coercimeters the measurement of the coercivity has become an important tool for the industry in quality control [1].
Due to the continued success the coercivity measurement techniques were first standardized in IEC 60404-7:1982 [2]. This standard has included the vibrating coil magnetometer [2,3], coercimeters with magnetic sensors near the sample as well as those with magnetic sensors outside the magnetizing coil [1,2].
After decades of only minor changes (e.g. in EU being integrated in EN 10330 [4,5]), a fully revised version was published in 2019. It reflected new findings in these measurements methods and also introduced the vibration sample magnetometer in an informative appendix [6]. However, even though it has been adapted as EN IEC 60404-7:2020 [7], not in all countries the new standard has yet been implemented (even not in EU). Among the users of these standards this results in a state of insecurity which method is in compliance with the new standard and what is the roadmap for introducing the standard on a national level.
This work will not only review the major changes of the new EN IEC 60404-7:2020 with a special focus on the challenges on measuring complex-shaped soft magnetic materials and addressing the roadmap for introduction of the new standard, but also will compare the new standard to other still valid national standards in the intermediate state.
References
[1] F. Foerster, Die schnelle und genaue Messung der Koerzitivkraft I, Archiv f. Techn. Messen, vol. 252-263,pp. 119–120, 1957, doi: 10.1524/teme.1957.252263.jg.119
[2] IEC 60404-7:1982, Magnetic materials – Part 7: Method of measurement of the coercivity of magnetic materials in an open magnetic circuit, 1982.
[3] H. Neumann, “Die Koerzitivkraft Hc , Definitionen und physikalische Meßgrundlagen,” Archiv f. Elektrotechnik, vol 39, 578–600, 1950. doi: 10.1007/BF01429757.
[4] EN 10330:2003, Magnetic materials – Method of measurement of the coercivity of magnetic materials in an open circuit, 2003.
[5] EN 10330:2015, Magnetic materials – Method of measurement of the coercivity of magnetic materials in an open circuit, 2015.
[6] IEC 60404-7:2019, Magnetic materials – Part 7: Method of measurement of the coercivity (up to 160 kA/m) of magnetic materials in an open magnetic circuit, 2019.
[7] EN IEC 60404-7:2020, Magnetic materials – Part 7: Method of measurement of the coercivity (up to 160 kA/m) of magnetic materials in an open magnetic circuit, 2020.
