超细金刚石包覆处理和P-G法制备粉体的研究

发布时间：2018-04-02 09:23

  本文选题：超细金刚石　切入点：二氧化钛　出处：《燕山大学》2015年硕士论文

【摘要】：本文在酸性条件下,利用二氧化钛包覆法来提高超细金刚石的分散性和抗氧化能力,利用高分子网络凝胶法制备多组分低温陶瓷结合剂,为制备超精磨陶瓷结合剂磨具打下良好的基础。以冰乙酸来控制TiO2的前驱体TBOT的水解速率,PVP为偶联剂,在乙醇和乙腈的混合溶液中对超细金刚石进行包覆处理,进而合成超细金刚石/二氧化钛(UFD/TiO2)复合材料。采用高分辨透射显微镜(HRTEM)对UFD/TiO2复合材料的结构和颗粒形貌进行了详细的分析;利用XRD对复合材料的物相进行了检测;通过FTIR分析可以看出其表面有PVP的N-C=O官能团和TiO2的Ti-O-Ti官能团存在;运用综合热分析(TG-DSC)和拉曼(Raman)分析了UFD/TiO2复合材料的抗氧化性能;通过在无机盐水溶液中的悬浮沉降性考察了UFD/TiO2复合材料在其中的分散性。实验结果表明:UFD/TiO2复合材料属于核壳结构,包覆的TiO2壳层厚度大约4nm,热处理后,其壳由原来的无定形转化为锐钛矿。包覆后的超细金刚石比原始的超细金刚石的抗氧化温度提高了约150℃,同时能稳定分散在多组分无机盐溶液中12 h而不出现团聚现象。运用高分子网络凝胶法制备陶瓷结合剂粉体时,着重考察了制备凝胶时的聚合温度,单体与交联剂的比例和引发剂的用量等工艺参数对多组份结合剂组织结构和性能的影响;采用XRD、FESEM、三点弯曲法和显气孔率测试仪等分析了结合剂的物相构成、显微结构特点、抗折强度与显气孔率。实验结果表明:当聚合温度为80℃,单体,交联剂和引发剂的比例为6:1:2时,可以得到凝胶时间短且性能良好的凝胶体;陶瓷结合剂的最佳煅烧温度为640℃,此时烧结的陶瓷结合剂的组织结构良好,其抗折强度为48.6 MPa,显气孔率为27.4%。
[Abstract]:In this paper, titanium dioxide coating method was used to improve the dispersion and oxidation resistance of ultrafine diamond under acidic conditions, and the multicomponent low temperature ceramic binder was prepared by polymer network gel method. The superfine diamond was coated in the mixed solution of ethanol and acetonitrile by using glacial acetic acid to control the hydrolysis rate of TiO2 precursor TBOT as coupling agent. The structure and particle morphology of UFD/TiO2 composites were analyzed by high resolution transmission microscope (HRTEM), and the phase of the composites was detected by XRD. FTIR analysis shows that there are N-C=O functional groups of PVP and Ti-O-Ti functional groups of TiO2, and the oxidation resistance of UFD/TiO2 composites is analyzed by comprehensive thermal analysis (TG-DSC) and Raman Raman. The dispersion of UFD/TiO2 composites in aqueous solution of inorganic salts was investigated by suspension settlement. The experimental results show that the structure of TiO2 / TiO2 composite is core-shell structure, and the thickness of coated TiO2 shell is about 4nm. after heat treatment, The shell changed from amorphous to anatase. The oxidation resistance temperature of the coated ultrafine diamond was increased by 150 鈩，

本文编号：1699748