title: Exchange coupling interaction in L10-FePd/α-Fe nanocomposite magnets with large maximum energy products.
abstract: Nanocomposite magnets (NCMs) consisting of hard and soft magnetic phases are expected to be instrumental in overcoming the current theoretical limit of magnet performance. In this study, structural analyses were performed on L1(0)-FePd/α-Fe NCMs with various hard/soft volume fractions, which were formed by annealing Pd/γ-Fe(2)O(3) heterostructured nanoparticles and pure Pd nanoparticles. The sample with a hard/soft volume ratio of 82/18 formed by annealing at 773 K had the largest maximum energy product (BH(max) = 10.3 MGOe). In such a sample, the interface between the hard and soft phases was coherent and the phase sizes were optimized, both of which effectively induced exchange coupling. This exchange coupling was directly observed by visualizing the magnetic interaction between the hard and soft phases using a first-order reversal curve diagram, which is a valuable tool to improve the magnetic properties of NCMs.
authors.affiliation: Advanced Material Engineering Division, Toyota Motor Corporation, 1200 Mishuku, Susuno, Shizuoka 410-1193, Japan.
authors.forename: Noritsugu
authors.initials: N
authors.lastname: Sakuma
authors.forename: Tsubasa
authors.initials: T
authors.lastname: Ohshima
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shoji
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Ryota
authors.initials: R
authors.lastname: Sato
authors.forename: Ayako
authors.initials: A
authors.lastname: Wachi
authors.forename: Akira
authors.initials: A
authors.lastname: Kato
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kawai
authors.forename: Akira
authors.initials: A
authors.lastname: Manabe
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Teranishi