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以叶蜡石、金红石和焦炭粉为原料,通过碳热还原–氮化反应合成sialon–Ti(N,C)复合材料。利用X射线衍射仪、扫描电子显微镜和能谱仪对产物的物相组成、显微结构和微区成分进行了分析,研究了合成温度和配炭量对产物物相组成和显微形貌的影响。结果表明:当叶蜡石与金红石质量比为4:1、配炭量过量50%、合成温度为1 500℃时,合成的sialon–Ti(N,C)复合材料中TiN0.7C0.3晶粒尺寸约为200nm,产物为β-sialon、15R-sialon、TiN0.7C0.3、刚玉和少量β-SiC;当配炭量过量50%,合成温度从1400℃升高到1550℃,产物中β-sialon和TiN0.7C0.3含量逐渐增加。相同合成温度下,配炭量对产物物相组成有重要影响,配炭量过量50%有利于sialon–Ti(N,C)复合材料的合成;当配炭量较少时,产物中出现O’-sialon和Si2N2O;当配炭量过多时,β-sialon向15R-sialon转变。
Sialon-Ti (N, C) composites were synthesized by pyrolytic reduction-nitridation using pyrophyllite, rutile and coke as raw materials. The phase composition, microstructure and micro-composition of the product were analyzed by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The effects of synthesis temperature and amount of carbon on the phase composition and microstructure of the product influences. The results show that when the mass ratio of pyrophyllite to rutile is 4: 1, the amount of carbon is over 50% and the synthesis temperature is 1 500 ℃, the TiN0.7C0.3 crystal in the synthesized sialon-Ti (N, C) The size of the particles is about 200nm, the products are β-sialon, 15R-sialon, TiN0.7C0.3, corundum and a small amount of β-SiC. When the amount of carbon is over 50%, the synthesis temperature is raised from 1400 ℃ to 1550 ℃. β-sialon and TiN0.7C0.3 content gradually increased. At the same synthesis temperature, with the amount of carbon on the product phase composition has an important impact, with an excess of carbon content of 50% is conducive to the synthesis of sialon-Ti (N, C) composites; with less carbon, the product appears O ’-sialon and Si2N2O; β-sialon transitions to 15R-sialon when there is too much carbon present.