【作者】 戴鼎汉；

【导师】 侯华；

【作者基本信息】 中北大学 ， 材料加工工程， 2009， 硕士

【摘要】 软磁NiCuZn铁氧体材料是应用非常广泛的一种功能材料。它在广播、电视、电子仪表、计算机等领域中得到越来越广泛的应用而且,器件及整机可以小型化、轻量化。所以研究NiCuZn铁氧体材料是软磁铁氧体研究的一个重要方向。本文以硫酸镍、硫酸铜、硫酸锌、硫酸亚铁和草酸铵为原料,应用化学共沉淀法制得分布均匀的前驱粉,经烘干、煅烧制成成分均匀性极佳的NiCuZn铁氧体粉末,再经成形和烧结等工艺,最后制得环形NiCuZn铁氧体材料。采用DSC、TEM、EDS、XRD、VSM和SEM观察铁氧体微观组织来评估了上述各因素对铁氧体性能的影响。通过详细的条件试验研究,确定前驱粉制备过程中的反应温度、反应时间、搅拌速度以及反应物配比等控制因素的最佳反应条件为:反应温度50℃、搅拌速度300r/min、反应时间2h、反应物配比（COO）^2-:Me²⁺=1.2。在以上最佳条件下,可制得分散性良好、粒径为20～30nm,收率97.1%的前驱粉产品。将制备得到的前驱粉进行煅烧实验,确定前驱粉煅烧过程中煅烧时间、煅烧温度最佳煅烧条件为:煅烧温度800℃、煅烧时间2h。在此条件进行可得到可得到饱和磁化强度为52emu/g、粒子粒径为50nm左右的铁氧体产品。进行了NiCuZn铁氧体烧结试验。对添加微量添加剂H₃BO₃、成型工艺和烧结条件进行了试验研究,得出了最佳烧结工艺条件。结果表明:压型压力为300MPa,保压时间4min;升温速度100℃/h,350℃～400℃保温2h可以有效地排除粘结剂PVA;烧结温度900℃、保温4h,随炉冷却;添加剂H₃BO₃的添加量为1%。在此工艺条件下烧结体密度为4.52g/cm³,饱和磁化强度为65.55emu/g。更多还原

【Abstract】 Soft magnetic NiCuZn ferrite materials is a wide used functional materials.It is wider and wider used in many fields,for example broadcast,television,electronic meter and computer etc,what more the apparatus will be come less and more diminutive.So the study of NiCuZn ferrite materials is an important way.In this paper,nano-particles of NiCuZn ferrites powders were prepared with nickel nitrate,zinc sulfate,copper sulfate and ferrous sulfate as starting materials and ammonium oxalate as the precipitator by employing co-precipitation technique using oxalate precursors.Excellent composition uniformity NiCuZn ferrite powder can be obtained after drying and calcination.Toroidal samples were obtained after being formed and sintered.The impact of the factors discussed above on the magnetic properties of NiCuZn ferrites was assessed by using DSC,TEM, EDS,XRD,VSM,SEM and optical microscopy to investigate the microstructure of the ferrites.Test conditions detailed studies to determine the precursor powder in the process of reaction temperature,reaction time,stirring speed and reaction ratio control factors such as the optimum reaction conditions:reaction temperature 50℃,stirring speed 300 r/min, reaction time 2 h,reactant ratio（COO）^2-:Me²⁺=1.2.Under the best conditions in the above, the precursor powder products which have a good dispersion,particle size of 20～30 nm and yield 97.1%can be obtained.The prepared precursor powder take calcining experiments to determine the course of precursor powder calcined time.The best calcination temperature of calcination conditions: calcination temperature 800℃,calcination time 2 h.The saturation magnetization of NiCuZn ferrite can be available for 52emu/g and the particle size of 50 nm products is around the ferrite conditions.NiCuZn ferrite sintering experiment has been taken.Add trace additives on the H₃BO₃,forming process and sintering conditions were studied,to draw the best sintering conditions.The results showed that:the best pressure-type pressure is 300 MPa and pressure time is 4 min;the samples should be heat treated at 350～400℃for 2 hours in order to completely eliminate the PVA and take warming rate of 100℃/h;the sintering temperature and the sintering time have been taken that is 900℃and 4 h,cooling with the furnace;additives H₃BO₃ of its adding is 1%.Under the conditions of this process the density of sintered bodies is 4.52g/cm³ and the Saturation magnetization can be for 65.55emu/g.更多还原