材料科学
凝聚态物理
矫顽力
微磁学
磁化反转
剩磁
各向同性
磁铁
Stoner–Wohlfarth模型
磁化
铁磁性
磁各向异性
磁场
光学
物理
量子力学
作者
Li Lou,Yuqing Li,Xiaohong Li,Hailing Li,Wei Li,Yingxin Hua,Weixing Xia,Zhihe Zhao,Haitian Zhang,Ming Yue,Xiangyi Zhang
标识
DOI:10.1002/adma.202102800
摘要
Abstract High‐performance ferromagnetic materials are essential for energy conversion and electronic devices. However, the random and nonuniform magnetization reversal in ferromagnetics limits their performance that can be achieved. Here, through both micromagnetism simulations and experiments, a directional magnetization reversal that initiates first from large grains toward smaller ones is discovered by engineering Nd 2 Fe 14 B/α‐Fe gradient nanostructures. Such directional magnetization reversal enables a rare combination of high magnetization and large coercivity, thus leading to a record‐high energy density (26 MG Oe) for isotropic permanent magnetic materials, which is ≈50% higher than that of its gradient‐free counterpart. The unusual magnetization reversal originates from an ordered arrangement of grain sizes in the gradient material, where the large grains have a lower reversal field than that of the smaller ones. These findings open up new opportunities for developing high‐performance magnetic materials.
科研通智能强力驱动
Strongly Powered by AbleSci AI