State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.
Sci Rep. 2017 Mar 6;7:43759. doi: 10.1038/srep43759.
We synthesized orthorhombic FeB-type MnB (space group: Pnma) with high pressure and high temperature method. MnB is a promising soft magnetic material, which is ferromagnetic with Curie temperature as high as 546.3 K, and high magnetization value up to 155.5 emu/g, and comparatively low coercive field. The strong room temperature ferromagnetic properties stem from the positive exchange-correlation between manganese atoms and the large number of unpaired Mn 3d electrons. The asymptotic Vickers hardness (AVH) is 15.7 GPa which is far higher than that of traditional ferromagnetic materials. The high hardness is ascribed to the zigzag boron chains running through manganese lattice, as unraveled by X-ray photoelectron spectroscopy result and first principle calculations. This exploration opens a new class of materials with the integration of superior mechanical properties, lower cost, electrical conductivity, and fantastic soft magnetic properties which will be significant for scientific research and industrial application as advanced structural and functional materials.
我们采用高温高压法合成了正交 FeB 型 MnB（空间群：Pnma）。MnB 是一种很有前途的软磁材料，具有高达 546.3 K 的居里温度，高达 155.5 emu/g 的高磁化值，以及相对较低的矫顽力。室温铁磁性源于锰原子之间的正交换相关作用以及大量未配对的 Mn 3d 电子。渐近维氏硬度（AVH）高达 15.7 GPa，远高于传统铁磁材料。高硬度归因于贯穿锰晶格的锯齿状硼链，这一点可以通过 X 射线光电子能谱结果和第一性原理计算得到证实。这项研究开辟了一类新的材料，兼具优异的力学性能、低成本、导电性和出色的软磁性能，这对于作为先进结构和功能材料的科学研究和工业应用将具有重要意义。
