微波合成纳米TiC粉体及分散性研究

发布时间：2018-04-25 00:10

  本文选题：微波 + 合成　； 参考：《西南科技大学》2016年硕士论文

【摘要】：本论文采用纳米二氧化钛和纳米炭黑作为原料,在连续式微波窑中合成纳米碳化钛粉体,达到规模化生产碳化钛的目的。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、激光粒度分布等分析手段,研究微波加热时间、原料类型、摩尔比例等因素对TiC粉体合成的影响。结果表明:较佳微波加热时间为100 min;采用锐钛矿型纳米TiO_2为原料有利于合成单相碳化钛粉体;采用锐钛矿型TiO_2和乙炔炭黑为原料,摩尔比例为1:3.5时,合成碳化钛粉体的平均晶粒尺寸为47.30 nm;碳黑的相对掺量越高,合成TiC的化学计量越接近TiC的理论化学计量。采用聚丙烯酸作为分散剂,无水乙醇作为分散介质,对原料进行表面改性处理,处理后的原料通过湿磨混合,在间歇微波窑中合成碳化钛粉体。利用Zeta电位测试、粘度测试、X射线衍射(XRD)、激光粒度分布等分析手段,研究pH值、分散剂、球磨等原料表面改性及混料工艺对微波合成TiC粉体的物相组成、化学计量、粒度分布的影响。结果表明:原料分散处理使微波合成TiC粉体的温度降低了150℃,提高了TiC粉体的纯度,减小了TiC的晶粒及平均晶粒尺寸,TiC粉体的化学计量更准确;Ti O_2和乙炔炭黑的较佳改性pH值均为4,其较佳分散剂用量分别是2.4 wt.%和9.0 wt.%,TiO_2和碳黑的较佳分散浓度分别为4.67 wt.%和2 wt.%;TiO_2和碳黑混合原料悬浮液的较佳分散pH为4,较佳分散剂用量为4.38 wt.%,较佳分散浓度为6.67wt.%,较佳球磨混料时间为6 h;合成TiC粉体的较佳配方为TiO_2:炭黑=1:3(摩尔比),合成TiC粉体的平均晶粒为27.59 nm。采用聚丙烯酸作为分散剂,去离子水为分散介质,对合成碳化钛粉体进行超声分散处理,利用激光粒度分布、Zeta电位测试、傅立叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)等分析手段,研究超声时间、分散剂浓度、pH值对碳化钛分散性的影响。结果表明:经过分散处理能显著降低纳米TiC粉体的团聚,分散性良好,平均粒径为0.032μm;较佳超声时间为4 min,较佳pH值为4,较佳分散剂(聚丙烯酸)用量为1.8 wt.%。
[Abstract]:In this paper, nanometer titanium carbide powder was synthesized in a continuous microwave kiln with nanometer titanium dioxide and nano carbon black as raw materials, and the purpose of producing titanium carbide on a large scale was achieved. By means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser particle size distribution, the effects of microwave heating time, type of raw materials and molar ratio on the synthesis of TiC powders were studied. The results show that the optimum microwave heating time is 100min, the anatase nanometer TiO_2 is used as the raw material to synthesize the single phase titanium carbide powder, the anatase type TiO_2 and acetylene carbon black are used as raw materials, the molar ratio is 1: 3.5. The average grain size of synthesized titanium carbide powder is 47.30 nm, and the higher the relative content of carbon black is, the closer the stoichiometry of synthetic TiC is to the theoretical stoichiometry of TiC. Using polyacrylic acid as dispersant and anhydrous ethanol as dispersing medium, the raw materials were treated by surface modification. The treated raw materials were mixed by wet grinding to synthesize titanium carbide powder in intermittent microwave kiln. By means of Zeta potential test, viscosity measurement, X-ray diffraction and laser particle size distribution, the phase composition and stoichiometry of TiC powder synthesized by microwave were studied by the surface modification of raw materials such as pH value, dispersant, ball milling and blending process. The effect of particle size distribution. The results showed that the temperature of TiC powder synthesized by microwave was reduced by 150 鈩，

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