Journal Article

Influence of High-Pressure Nitrogenation on the Structure, Magnetism and Microwave Absorption Properties of SmFeloMO2

Nai-Kun Sun Jie Guo Sheng-Jie Du Song-Ning Xu Ping-Zhan Si Jin-Jun Liu

2015

Overview

Nitrogenation of SmFelolVIo2 powders was performed in a self-made furnace under a high-purity N2 atmo- sphere up to 40 MPa at 500 ℃. Upon nitrogenation at atmospheric pressure, the lattice parameters a and c increase by 0.5% and 2.7%, respectively, whereas the Curie temperature Tc increases from 519 to 633 K. With further increasing the nitrogenation pressure to 20 and 40 MPa, the 1：12 main phase starts to decompose and a large amount of Mo and a-Fe precipitates. This leads to variation of Mo concentration in the 1：12 phase and causes a sharp decrease in Tc and in the coercivity. The relative complex permittivity and permeability of paraffin-SmFeloMO2 composites show multi-resonant behavior. After nitrogenation, the magnetic loss of the powders decreases, which may originate from the influence of eddy currents due to the increase in the particle size.

• Subject: 居里温度 / 微波吸收 / 性质 / 晶格参数 / 氮化 / 磁性 / 结构 / 高压