本文選題：超細(xì)金剛石　切入點(diǎn)：二氧化鈦　出處：《燕山大學(xué)》2015年碩士論文

【摘要】：本文在酸性條件下,利用二氧化鈦包覆法來(lái)提高超細(xì)金剛石的分散性和抗氧化能力,利用高分子網(wǎng)絡(luò)凝膠法制備多組分低溫陶瓷結(jié)合劑,為制備超精磨陶瓷結(jié)合劑磨具打下良好的基礎(chǔ)。以冰乙酸來(lái)控制TiO2的前驅(qū)體TBOT的水解速率,PVP為偶聯(lián)劑,在乙醇和乙腈的混合溶液中對(duì)超細(xì)金剛石進(jìn)行包覆處理,進(jìn)而合成超細(xì)金剛石/二氧化鈦(UFD/TiO2)復(fù)合材料。采用高分辨透射顯微鏡(HRTEM)對(duì)UFD/TiO2復(fù)合材料的結(jié)構(gòu)和顆粒形貌進(jìn)行了詳細(xì)的分析;利用XRD對(duì)復(fù)合材料的物相進(jìn)行了檢測(cè);通過(guò)FTIR分析可以看出其表面有PVP的N-C=O官能團(tuán)和TiO2的Ti-O-Ti官能團(tuán)存在;運(yùn)用綜合熱分析(TG-DSC)和拉曼(Raman)分析了UFD/TiO2復(fù)合材料的抗氧化性能;通過(guò)在無(wú)機(jī)鹽水溶液中的懸浮沉降性考察了UFD/TiO2復(fù)合材料在其中的分散性。實(shí)驗(yàn)結(jié)果表明:UFD/TiO2復(fù)合材料屬于核殼結(jié)構(gòu),包覆的TiO2殼層厚度大約4nm,熱處理后,其殼由原來(lái)的無(wú)定形轉(zhuǎn)化為銳鈦礦。包覆后的超細(xì)金剛石比原始的超細(xì)金剛石的抗氧化溫度提高了約150℃,同時(shí)能穩(wěn)定分散在多組分無(wú)機(jī)鹽溶液中12 h而不出現(xiàn)團(tuán)聚現(xiàn)象。運(yùn)用高分子網(wǎng)絡(luò)凝膠法制備陶瓷結(jié)合劑粉體時(shí),著重考察了制備凝膠時(shí)的聚合溫度,單體與交聯(lián)劑的比例和引發(fā)劑的用量等工藝參數(shù)對(duì)多組份結(jié)合劑組織結(jié)構(gòu)和性能的影響;采用XRD、FESEM、三點(diǎn)彎曲法和顯氣孔率測(cè)試儀等分析了結(jié)合劑的物相構(gòu)成、顯微結(jié)構(gòu)特點(diǎn)、抗折強(qiáng)度與顯氣孔率。實(shí)驗(yàn)結(jié)果表明:當(dāng)聚合溫度為80℃,單體,交聯(lián)劑和引發(fā)劑的比例為6:1:2時(shí),可以得到凝膠時(shí)間短且性能良好的凝膠體;陶瓷結(jié)合劑的最佳煅燒溫度為640℃,此時(shí)燒結(jié)的陶瓷結(jié)合劑的組織結(jié)構(gòu)良好,其抗折強(qiáng)度為48.6 MPa,顯氣孔率為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，

本文編號(hào)：1699748