纳米晶SmCo_(8.9)Si_(0.9)永磁合金相变特征及其磁性能变化研究  

Phase Transformation and Magnetic Properties of Nanocrystalline SmCo_(8.9)Si_(0.9) Alloy

作　　者：刘东 王海滨[1] 刘雪梅[1] 华刚 宋晓艳[1] Liu Dong Wang Haibin Liu Xuemei Hua Gang Song Xiaoyan(Key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing University of Technology, Beijing 100124, China)

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100124

出　　处：《稀有金属材料与工程》2017年第9期2539-2545,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51371012);国家杰出青年科学基金(51425101)

摘　　要：首次制备出具有高稳定性的Sm Co_(8.9)Si_(0.9)纳米晶合金,进而系统研究了亚稳相Sm Co_(8.9)Si_(0.9)的相变特征及相应的磁性能变化规律。发现添加元素Si可以有效提高过饱和固溶体亚稳相SmCo_(9.8)的稳定性,随着热处理温度的升高,SmCo_(8.9)Si_(0.9)纳米晶合金由SmCo_(9.8)(H)结构的单相转变为Sm_2Co_(17)(H)和Co(fcc)相,且伴随相变,矫顽力提高。其机理源于析出的细小Co相造成钉扎机制增强。进一步升高热处理温度,Sm_2Co_(17)(H)相转变为Sm_2Co_(17)(R)相,同时晶粒长大明显且晶粒尺寸分布不均匀,导致磁性能下降。The nanocrystalline Sm Co_（8.9）Si_（0.9） alloy with a high stability was first prepared and then a systematic study was carried out on the phase transformation and corresponding magnetic properties of the metastable Sm Co_（8.9）Si_（0.9） phase. The results reveal that the addition of Si greatly improves the stability of the metastable supersaturated solid solution Sm Co_（9.8）. With the increase of the heat-treatment temperature,the nanocrystalline Sm Co_（8.9）Si_（0.9） alloy transforms from the Sm Co_（9.8）（H） phase to the Co（fcc） phase and the coercivity is correspondingly improved. The mechanism is that the precipitated fine Co phase enhances the pinning effect. With a further increase in temperature,the Sm_2Co_（17）（H） phase transforms into Sm_2Co_（17）（R） accompanied with an evident grain growth and an inhomogeneous grain size distribution,decreasing the magnetic properties.

关 键 词：Sm-Co合金 亚稳相 相稳定性 矫顽力机制 

分 类 号：TG132.27[一般工业技术—材料科学与工程]