蛋清途径制备Ni-Cu铁氧体粉体及陶瓷材料研究

【作者】 李智东；

【导师】 赵昆渝；

【作者基本信息】 昆明理工大学 ， 材料学， 2012， 硕士

【摘要】 Ni-Cu类铁氧体是一类具有广泛用途的低温烧结软磁铁氧体材料。其广泛应用于多路通信、开关电源、录音和录象的各种记录磁头、信息存储系统、医疗诊断等领域,近年来随着无线电、移动电话、广播电视的迅速发展,特别是铁氧体在片式电感器、抗电磁干扰(EMI)和射频干扰(RFI)磁芯的应用越来越广,对Ni-Cu铁氧体材料提出了越来越高的要求。蛋清途径是使用新鲜鸡蛋清作为复合络合剂来制备铁氧体的一种新方法,它与共沉淀方法相比可以不用控制混合溶液的PH值,工艺步骤更加简单。本论文主要采用不同方法制备镍铜铁氧体微细粉体,并进而采用固相反应法制备镍铜铁氧体陶瓷材料,并分别对镍铜铁氧体粉体和陶瓷材料的制备工艺、物相及磁学性能等进行了研究,论文主要工作包括以下部分。本实验以硝酸镍Ni(NO3)3·6H2O、硝酸铜Cu(NO3)2·3H2O、硝酸铁Fe(NO3)3·9H2O以及硝酸锌Zn(NO3)2·6H2O为原料,以蛋清作为复合络合剂,通过在不同焙烧温度、不同保温时间下制备Ni0.6Cu0.4Fe2O4微细粉粉体,优化制备工艺条件,成功制备出名义配比为Ni(1-x)CuxFe2O4(x=0、0.2、0.4、0.6、0.8)以及Ni0.25Cu0.25Zn0.5Fe2O4的微细粉体。通过对粉体样品的XRD、粒度、磁滞回线的测定分析,最终确定蛋清法制备Ni(i1-x)CuxFe2O4(x=0、0.2、0.4、0.6、0.8)以及Ni025Cu0.25Zn0.5Fe2O4的较佳制备工艺为：温度台阶为240℃保温1h,升温至440℃再保温2h,最高焙烧温度为520℃,保温时间为6h。实验结果表明,在较佳工艺条件下制备不同掺量的Ni(1-x)CuxFe2O4,当Cu掺量为0.4时,Ni(1-x)CuxFe2O4粉体样品颗粒粒径较小,粒度分布相对比较均匀,且磁学性能相对较好。以蛋清作为复合络合剂制备的镍铜铁氧体微细粉末为原料,经固相反应法,制备Ni1-xCuxFe2O4(x=0,0.2,0.4,0.6,0.8)和Ni0.25Cu0.25Zn0.5Fe2O4铁氧体陶瓷材料。主要研究烧结工艺和铜含量对Ni-Cu系铁氧体陶瓷材料显微结构和性能的影响。采用XRD和金相分析研究陶瓷样品的物相和微观结构,对所制备陶瓷样品的磁导率μ、相对介电常数εr和电阻率p进行了测试分析。研究结果表明：采用较细的粉体有利于NiCu铁氧体主相的形成,较高的烧结温度容易出现CuO杂相和晶粒异常长大现象；通过对样品的磁导率、介电常数和电阻率频谱分析表明,室温下106～108Hz频率范围内,Ni1-xCuxFe2O4(x=0.0,0.2,0.4,0.6,0.8)铁氧体陶瓷材料,当铜掺量为0.4时,样品磁导率和电阻率最大；Ni0.25Cu0.25Zn0.5Fe2O4陶瓷样品的磁学性能相对Ni1-xCuxFe2O4较好。更多还原

【Abstract】 Ni-Cu ferrite is a kind of low temperature sintered ferrite material with extensive use. It is widely used in multiple accesses, switching powder supplies, various recording heads of audio and video, information storage systems, medical diagnosis, and so on. In recent years, as the rapid development of radios, mobile phones and television, especially the wider use of ferrite on chip inductors, EMI and RFI, the requirements on the Ni-Cu ferrite materials are higher and higher. The method using fresh egg white as composite complexing agent to prepare ferrite is a new method, which is a more simple process than co-deposition method and unnecessary to control the PH value of the mixture.This paper study on the preparition of Ni-Cu ferrite fine particle and ceramics, then research the technological conditions of preparation, phase and their property of magnetic performance etal. The main works are as following:Ni0.6Cu0.4Fe2O4fine particles were synthesized with Ni(NO3)3·6H2O, Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, Zn(NO3)2·6H2O and egg white. The better technological conditions of preparation were gained. Ni(1-x)CuxFe2O4(x=0、0.2、0.4、0.6、0.8) and Ni0.25Cu0.25Zn0.5Fe2O4fine particles were synthesized at this technological conditions. By the determination of XRD, particle size and hysteresis loop, the better technological conditions with egg white as composite complexing agent is:240℃/1h-440℃/2h-520℃/6h. Ni0.6Cu0.4Fe2O4powder samples have smaller particle size, relatively uniform particle size distribution, and relatively good magnetic properties.With Ni(NO3)3·6H2O, Cu(NO3)2·3H2O, Fe(NO3)3·9H2O, Zn(NO3)2·6H2O as raw material and egg white as composite complexing agent, Ni1-xCuxFe2O4(x=0.0,0.2,0.4,0.6,0.8) and Nio.25Cuo.25Zno.5Fe2O4ceramics were sintered by solid-state reaction. This paper lays emphasis on the research of the sintering temperature and copper content to impact Ni-Cu ferrite microstructure and properties.The investigation of ceramic samples of microscopic structure and content of ceramic samples used XRD analysis and metallographic analysis and magnetic conductivity μ,dielectric parameters sr and resistivity p had been tested and analyzed, so as to gradually improve ferrite ceramic materials preparation techniques. The results of the study show that:Using fine powder maked for the formation of the major phase of ferrite, but it was easy growing up CuO impurity pharse and emerging abnormal grain growth when the sintering temperature rising; through magnetic conductivity, electrical resistivity and dielectric constant of the sample spectrum analyzed showing that, the magnetic conductivity and electrical resistivity of the content x=0.4of Ni1-xCuxFe2O4(x=0.0,0.2,0.4,0.6,0.8) ferrite ceramic materials is largest in frequency106～108Hz at room temperature; The magnetism performance of Ni0.25Cu0.25Zn0.5Fe2O4ceramic samples is better than Ni1-xCuxFe2O4.更多还原