纳米二硼化锆粉体的制备与表征 - 图文

辽宁科技大学本科生毕业设计（论文） 第I页

纳米ZrB2粉体的制备

摘 要

二硼化锆陶瓷粉体是一种黑色粉末，其化学分子式为：ZrB2，分子重量112.84，密度4.52g/cm3，是六方晶系的准金属结构化合物，是一种高级工程材料，在各个领域有着广泛应用。高熔点(3040℃)、高硬度、高稳定性以及良好的导电性、导热性、抗氧化性和抗化学腐蚀性，使以二硼化锆为原料制成的复合陶瓷综合性能优异。另外，二硼化锆具有良好的中子控制能力，可用于核工业。其各种优良特性使其成为很有发展前景的高性能耐火材料。采用了透射电镜(TEM)实验测试技术对制备的纳米粉体进行表征。以氯氧化锆为锆源，以NH3?H20与ZrOCL2?8 H20生产沉淀剂，利用特殊液相沉淀法制备了纳米Zr(OH)2粉体。将沉淀至于NH4BO3溶液中，分别用烘干和共沸剔除水分，消除使硼酸吸附纳米Zr(OH)2上，通过在氢气环境下，煅烧Zr(OH)2和NH4BO3消除氮氢氧，从而制得纳米硼化锆。在上通过扫描电镜分析研究了锆源浓度、NH3?H20和H3BO3的用量、溶胶pH值、陈化时间等因素对硼化锆颗粒大小的影响。本文实验研究部分研究了用NH4?H20为沉淀剂法制得的纳米硼化锆粉体，颗粒粒径随硼酸溶液的浓度增大而减小。研究在不同温度下煅烧Zr(OH)2和NH4BO3的混合物，与NH4Cl一起作为沉淀剂法制得的纳米二硼化锆粉体，颗粒粒径随温度的浓度增大而减小。

关键字：纳米；二硼化锆；制备；表征

Preparation of nano-ZrB2 powder

辽宁科技大学本科生毕业设计（论文） 第II页

Abstract

Diboride zirconium ceramic powder is a black powder, the chemical formulas for ZrB2, molecular weight 112.84, 4.52 g/cm3 density, is six FangJing department must metal structure compound, is a kind of advanced engineering materials, has a wide application in all fields. High melting point (3040 ℃), high hardness and high stability and good electrical conductivity and thermal conductivity, oxidation resistance and corroZrB2 resistance of chemical resistance, make with diboride zirconium as raw material made of composite ceramic comprehensive performance is excellent. In addition, diboride zirconium has good neutron control ability, can be used for the nuclear industry. The variety of fine properties that make it a very promising high performance refractory. This paper used the nano experimental center of our patent technology, special liquid preparation of nanometer particle ZrB2 precipitation. Using transmisZrBn electron microscopy (TEM) test technology on the preparation of nanometer powder characterized. To chlorine zirconia for zirconium source, NH3 ?H20 and ZrOCL2 ?8 H20 precipitation agent production, use special liquid preparation of nanometer Zr precipitation (OH) 2 powder. As for NH4BO3 solution will precipitation, respectively for drying and boiling water were eliminated, eliminate make boric acid adsorption nano Zr (OH) 2, through in the hydrogen environment, calcining Zr (OH) 2 and NH4BO3 eliminate nitrogen hydrogen and oxygen, which made the nano boron zirconium. By scanning electron microscopy (sem) in the source concentration, NH3 ? zirconium H20 and the dosage of the H3BO3, sol pH value, Chen factors such as the time of boron zirconium of particle size effect. The experiment research part is used to study the NH3 ? H20 precipitation agent for the legal system of the nano boron zirconium powder, with the particle size of boric acid solution concentration and decreases. Research in different temperature burning Zr (OH) 2 and NH4BO3 mixture of NH4Cl and together as the precipitation agent of the method, the nano diboride zirconium powder, the concentration of the particle size with temperature and decreases.

Key Words: nano; Diboride zirconium; Preparation; characterization

辽宁科技大学本科生毕业设计（论文） 第III页

目 录

摘 要 ...................................................................................................................... I 第一章 绪论 ......................................................................................................... 1

1.1 纳米科学与纳米材料 ..................................................................................................... 1 1.2 纳米二硼化锆的性质及应用 ......................................................................................... 2 1.2.1 纳米二硼化锆的性质 .............................................................................................. 2 1.2.2 纳米二硼化锆的应用 .............................................................................................. 3 1.3 纳米粉体的表征方法 ..................................................................................................... 5 1.4 论文的选题意义和目的 ................................................................................................. 5

第二章 纳米二硼化锆的制备方法 ..................................................................... 6

2.1 碳还原法制备ZRB2粉体 ................................................................................................ 6 2.2 硼化锆陶瓷材料的制备 ................................................................................................. 6 2.3 Sol-Gel法 ....................................................................................................................... 7 2.4 水热合成法 ..................................................................................................................... 7 2.5 超重力反应法 ................................................................................................................. 7 2.6 微乳液反应法 ................................................................................................................. 8 2.7 纳米ZRB2的CO2沉淀法制备 .......................................................................................... 8

第三章 纳米粉体制备机理的探讨 ..................................................................... 9

3.1 液相中胶粒析出过程 ..................................................................................................... 9 3.1.1 亚稳态及亚稳相 ...................................................................................................... 9 3.1.2 胶粒析出过程的推动力 .......................................................................................... 9 3.1.3 临界核与临界自由能 ............................................................................................ 10 3.1.4 成核速率公式 ........................................................................................................ 12 3.2 长大过程 ....................................................................................................................... 14 3.3 小粒子碰撞理论 ........................................................................................................... 14 3.4 晶粒析出过程中各种影响因素 ................................................................................... 15

辽宁科技大学本科生毕业设计（论文） 第IV页

3.5 LAMER图 ...................................................................................................................... 18 3.6 液相胶粒析出相变方程 ............................................................................................... 18 3.7 特殊液相沉淀法法制备纳米粉体的原理 ................................................................... 18

第四章 纳米二硼化锆的制备与表征 ................................................................ 21

4.1 纳米ZRB2的制备的药品与仪器 ................................................................................... 21 4.2 用氯化氨作为沉淀剂制备ZRB2的沉淀法 ................................................................... 23 4.2.1 纳米ZrB2粉体制备的实验机理 ............................................................................ 24 4.2.2 制备实验过程 ........................................................................................................ 24 4.2.3 透射电镜分析 ........................................................................................................ 25 4.3陈化时间对ZRB2颗粒的影响 ........................................................................................ 28 4.4 小结 ............................................................................................................................... 28

总 结 .................................................................................................................... 28 致谢 参考文献