Nucleation or pinning: Dominant coercivity mechanism in exchange-coupled permanent/composite magnets

Microstructure and Magnetic Properties of NdFeB Films through Nd Surface Diffusion Process

“…Moreover, the out-of-plane hysteresis loop shows two stage types of initial magnetization behavior with the first magnetization of high susceptibility followed by the second one of low susceptibility, which also suggests the independent magnetization of the uncoupled soft magnetic grains. Zhao et al proposed that Fe is very likely to occur in Nd 2 Fe 14 B so that many single-phased materials are in fact the two-phased ones [13].…”

“…It suggests a decrease in the size of the distorted region and/or a considerable release of interfacial misfit at the NdFeB layer of 750 nm [16]. Zhao et al proposed a self-pinning coercivity mechanism, incorporating elements of both initial local nucleation process and subsequent propagation of the domain wall to the main phase [13,17]. Such a mechanism was firstly proposed in hard-soft multilayers and then extended to composite and permanent nanomagnets.…”

Phase evaluation, magnetic, and electric properties of Mn60+xGa40−x (x = 0–15) ribbons

“…Based on the results of micromagnetic calculation, Zhao's group recently proposed that the dominant coercivity mechanism is self-pinning in most exchange-coupled permanent/composite magnets. 17,18 Such a pinning is attributed to the change of the intrinsic parameters associated with the phase change at the interface. The coercivity mechanism of Mn-Ga ribbons with exchange bias effects should be driven by such self-pinning mechanism.…”

A solution for the preparation of hexagonal M-type SrFe12O19 ferrite using egg-white: Structural and magnetic properties

“…3(c)), exhibits the largest H c . In fact, though the magnetic impurity results in the reduction of M s , it also could play a role as the pinning center that enhances the H c [31,32]. Therefore, the increase of H c for specimens with the same T s but increasing Sr/Fe could be attributed to the pinning effect from impurity.…”