Indirect yoke-based B-H hysteresis measurement method determining the magnetic properties of macroscopic ferromagnetic samples part I: Room temperature

This work describes an indirect determination method for magnetic flux density-field strength. (B-H) hysteresis measurement. Several electromagnetic measurement methods determining and analysing specific material properties are already established, but these are meant for laboratory measurements using small samples having only limited application possibilities. Such methods are the vibrating sample magnetometer, ring sample method, Epstein frame and other indirect methods, which are until now under continuous development. In the present work, a combination of the mentioned measurement setups based on a yoke setup was designed to measure magnetic behaviour of industrial samples in an indirect measurement setup having a wide range of application possibilities. This was realised using various corrections and a reluctance model for the magnetic circuit. Using a min. 70 vol-% pure iron particle filled flux conducting paste at the contact positions, the H-field loss called demagnetisation and caused by stray fields became insignificant. Interestingly, finite element model and experimental estimation result in about half of demagnetisation of the setup as the validation indicated. For validation purposes, a comparison with the results of a direct electromagnetic measurement method was established. Using the adjusted demagnetisation, the results were reasonably in line with the validation.