The 27th ESICMM Seminar
(FORC analysis of permanent magnets)
Magnetic Material FORC Measurement
Ms.Naomi Watanabe(2nd Section Engineering Division, TOYO Corporation)
First-order-reversal-curve (FORC) measurement is an advanced measurement method for examining the magnetic characteristics such as magnetic interaction and coercivity distribution, which the conventional hysteresis loop cannot obtain.
This measurement has been widely adopted among paleomagnetism researchers who investigate the magnetic properties in rocks and soils to determine the magnetic characteristics in these natural samples.
Recently materials researchers also began to conduct the FORC measurement to examine various magnetic materials such as permanent magnets, magnetic recording media, nanocomposite magnets, nanowire arrays.
In this seminar, I will start with explaining a basic idea of the FORC measurement and then introduce actual measurement methods and examples.
This measurement has been widely adopted among paleomagnetism researchers who investigate the magnetic properties in rocks and soils to determine the magnetic characteristics in these natural samples.
Recently materials researchers also began to conduct the FORC measurement to examine various magnetic materials such as permanent magnets, magnetic recording media, nanocomposite magnets, nanowire arrays.
In this seminar, I will start with explaining a basic idea of the FORC measurement and then introduce actual measurement methods and examples.
FORC analysis on permanent magnets
Prof. SATOSHI OKAMOTO ( IMRAM, Tohoku University)
First-order reversal curve (FORC) analysis has been utilized for the studies on various magnetic materials including permanent magnets. When the FORC diagram follows the Preisach model, the coercivity and interaction field distributions can be quantitatively analyzed. Recently we have found the FORC diagrams of hot-deformed Nd-Fe-B magnets are well represented by the Preisach model. On the other hand, the FORC diagram of sintered Nd-Fe-B magnets are quite different from the Preisach type one, but there are some unique features. In this seminar, I will explain the basic theories for the FORC analysis and how to understand the FORC diagrams of hot-deformed and sintered Nd-Fe-B magnets.