# Fileset

[Abstract_Navid.docx](https://mdr.nims.go.jp/filesets/eaf038d2-effb-4e02-bd76-97f638416bf3/download)

## Creator

[SEPEHRI AMIN Hossein](https://orcid.org/0000-0002-7856-7897)

## Rights

[Creative Commons BY-NC Attribution-NonCommercial 4.0 International](https://creativecommons.org/licenses/by-nc/4.0/)

## Other metadata

[Development of magnetic materials for green energy conversions](https://mdr.nims.go.jp/datasets/816204fc-8c93-4ad3-8514-953f79048ac5)

## Fulltext

Title Development of magnetic materials for green energy conversions Speaker: Navid H. Sepehri-Amin, National Institute for Materials Science, Tsukuba, JapanAbstract: Magnetic materials, such as soft and hard magnets, are essential for a wide range of energy conversion applications. Rising demands and emerging applications require these materials to operate closer to their theoretical limits while meeting sustainability challenges. Achieving this goal hinges on microstructure design and control across multiple length scales, guided by experiments and modeling. This talk will highlight several such strategies. In the first part, we demonstrate how introducing magnetoelastic anisotropy in soft magnetic materials can benefit different applications from Wiegand wires to the power electronic applications. Supported by micromagnetic simulations, we will show that optimum annealing in Fe-based amorphous ribbons with a large magnetostriction induces a small stress-induced perpendicular magnetic anisotropy. This promotes change of magnetic domain configuration from large curvilinear magnetic domain to the formation of narrow stripe-shaped domain and resulted in a change in high frequency magnetization switching mechanism. Unlike conventional approach that focus on necessity of low magnetostriction values to reduce core loss, we succeeded in 50 % reduction of core loss even in materials with large magnetostriction which can open materials choice for high frequency power electronic applications. In the second part of the talk, we present advances in high-coercivity Dy-free Nd–Fe–B permanent magnets with excellent thermal stability. These results stem from integrating advanced processing methods, multi-scale microstructural characterization, and microstructure-based micromagnetic simulations. Finally, we show how this combinatorial approach accelerates the development of Fe-rich SmFe₁₂-based sintered magnets with an optimized microstructure.