磁场对纳米MnZn铁氧体前驱体形貌的影响  

Effect of Magnetic Field on the Morphology of Nano-MnZn Ferrite Precursor

作　　者：钟云波[1] 李志华[1] 任忠鸣[1] 邓康[1] 徐匡迪[1] 

机构地区：[1]上海大学上海市现代冶金与材料制备重点实验室,上海200072

出　　处：《稀有金属材料与工程》2006年第8期1263-1267,共5页Rare Metal Materials and Engineering

基　　金：全国优秀博士学位论文作者基金(200235);国家自然科学基金(50404018);上海市科委纳米专项基金(0252nm048)

摘　　要：采用SEM,XRD,TEM,TG等手段研究了磁场对共沉淀法制备纳米MnZn铁氧体前驱体形貌及晶态结构的影响。结果表明,随着磁感应强度增大并达到某一临界值时,纳米颗粒形貌由球状向链状转变,继续增加磁感应强度将获得针状、棒状或纤维状的颗粒,10T强磁场下获得棒状颗粒呈现单晶结构。热重分析表明10T磁场下获得的纳米颗粒由于单维尺寸增加而导致活性降低。根据晶体生长理论,讨论了磁场影响纳米颗粒形核和长大过程的机理。Effect of magnetic field on the shape and crystalstructure of nano MnZn ferrite precursor prepared by co-precipitation way was studied by using SEM, XRD, TEM and TG. It was shown that the morphology of nano particles would change from spheric to chain-like with increasing the magnetic field to a certain critical value. The claviform-like nano particles obtained in a magnetic field of 10 T showed the structure information of single crystal. Thermal gravity curve revealed that the activity of nano particles was reduced in a magnetic field of 10 T due to the increase of one dimension size. The mechanism of magnetic field effect on the nano particle nucleation and growth was discussed by crystal growth theory.

关 键 词：纳米 MNZN铁氧体 磁场 晶体生长 形核 

分 类 号：TB383.1[一般工业技术—材料科学与工程]