高压下Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9纳米晶软磁块体合金的形成  

Formation of Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9 Nanocrystalline Soft Magnetic Bulk Alloys in High Pressure

作　　者：卢斌[1] 易丹青[1] 刘岩[2] 陆昌伟[2] 于惠梅[2] 

机构地区：[1]中南大学材料科学与工程学院,长沙410083 [2]中科院上海硅酸盐研究所,上海200050

出　　处：《无机材料学报》2004年第5期1138-1144,共7页Journal of Inorganic Materials

基　　金：湖南省自然科学基金(01YJJ2056);北京工业大学新型功能材料教育部重点实验室基金

摘　　要：采用MA法和低温高压固结工艺制备了Fe73.5Cu1Nb3Si13.5B9软磁合金粉末和块体合金,借助XRD、DSC、SEM、TEM手段分析了它们的相组成、平均晶粒尺寸以及粉末的热稳定性、块体合金的相对密度.结果表明:(1)经过70h MA后,可获得平均晶粒尺寸约9.5nm、bcc结构的单相α-Fe纳米晶过饱和固溶体粉末;(2)在DSC的升温曲线中,分别出现四个强弱不一的放热峰,依次对应着发生了畸变的纳米晶过饱和固溶体的结构弛豫过程、少量非晶晶化过程以及过饱和固溶体的相析出过程,且过饱和固溶体析出过程分两个阶段完成;(3)在P=5.5GPa,Pw=980W,t=5min的烧结条件下,可获得相对密度约98.4％、平均晶粒尺寸约12.5nm的单相α-Fe纳米晶块体合金,该块体合金的软磁性能为:比饱和磁化强度Ms=1.71×10-7wb·m/g,矫顽力Hc=8.22×103A/m.Fe73.5Cu1Nb3Si13.5B9 soft magnetic alloy powders and its bulk alloys were prepared by the mechanical alloying (MA) method and cryogenical high pressure solidification process. Phase components, average grain size, thermal stability of powders and relative density of bulk alloys of the samples were analyzed by XRD, DSC, SEM and TEM. The results showed that (1) after MA for 70 hours, bcc single phase alpha-Fe nanocrystalline supersaturate solid solution powders with average grain size 9.5nm can be obtained; (2) four exothermal peaks with different intensity appeared in DSC heating-up curves, these peaks corresponded to structural relaxation of distorted nanocrystalline supersaturate solid solution, crystallization of small quantity amorphous and phase precipitation of supersaturate solid solution, respectively. Phase precipitation of supersaturate solid solution included two stages; (3) under the sintering conditions of P=5.5GPa, t=5min and P-w=980W, single phase a-Fe nanocrystalline bulk alloys with 98.4% relative density and about 12.5nm average grain size can be obtained, soft magnetic properties of the bulk alloys were specific saturation magnetization M-s = 1.71 X 10(-7) Wb(.)m/g, coercive force H-c = 8.22 x 10(3) A/m.

关 键 词：Fe基软磁合金 MA 高压成型 纳米晶 

分 类 号：TM27[一般工业技术—材料科学与工程] TF123[电气工程—电工理论与新技术]