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1、 I 摘要摘要 微晶玻璃又称玻璃陶瓷或结晶化玻璃，是对具有特定组成的基础玻璃采用特殊的热处理工艺手段，在玻璃相中生成尺寸细小、均匀分布的晶体而获得一种晶态与非晶态的混合材料。微晶玻璃的研制成功具有十分重要的实际使用价值和理论研究价值，大大加深了人类对玻璃的相变及其与玻璃结构、性能关系的认识，推动了玻璃科学的发展，开辟了一条制造多晶材料的新途径。 本实验采用分析纯碳酸钙、氧化铝、碱式碳酸镁和二氧化硅为主要原料，采用熔融法制备CaO-MgO-Al2O3-SiO2系玻璃。首先，根据微晶玻璃组成设计原理确定三个组分不同的配方， 通过对熔制结果的观察分析、差热分析和析晶结果的分析，得到最适合本实验研究的
2、玻璃组分配比 为 ： CaO25% ， MgO15% ， Al2O310% ， SiO250% ， Sb2O32% 。 该 配 方 下 的CaO-MgO-Al2O3-SiO2系玻璃在 850下无析晶现象， 在 1010左右析晶现象明显， 析出的晶相主要是辉石和透辉石。 按照该实验最佳的组成比例，采用 7 种不同的热历史条件制备基础玻璃，分别为：在水中冷却； 铁板上空冷； 650下退火10h； 700下退火 10h； 750下退火 10h； 800下退火 10h；850下退火 10h。对得到的基础玻璃进行 DTA、IR 和 SEM 等测试技术探讨CMAS 系玻璃在不同热历史条件下，析晶动力学参数
3、的变化，分相对晶化行为的影响。分析结果表明：同种组成，不同热历史条件下CMAS 系玻璃析晶放热峰的面积和峰高有明显的不同，其析晶活化能 E、晶化指数 n 也不同。随着退火温度的上升，新相的积聚程度越来越分散，液滴状的颗粒逐渐连接成分散的蠕虫状的链条，然后又相互收拢重叠在一起。热历史条件的改变主要对玻璃中缔合的SiO4四面体中键产生影响， 随着退火温度的上升， 缔合的SiO4中Si-O-Si、Si-O-不对称伸缩振动增强，缔合的SiO4中Si-O-三重简并弯曲振动随着退火温度的上升，先增强后又减弱。 最后，按照不同热历史条件下的差热分析结果，在各自的析晶温度下保温 4h，让样品充分析晶，然后利用
4、 XRD、SEM 和红外光谱分析等实验手段，探讨不同热历史对该系微晶玻璃析晶的影响，主晶相的数目随着保温温度的上升而上升，次晶相的数目没有明显变化。微晶玻璃的微观结构与分相的形貌状态具有继承性，分相的形貌状态决定了析晶后的微晶玻璃的微观结构和形貌。最后通过对得到样品的性能测试，表明不同热历史对该系微晶玻璃的密度、耐酸碱性和显微硬度有着重要的影响。微观结构及原子基团的堆积密度决定了不同热历史条件下微晶玻璃的密度，随着保温温度的上升，密度呈先下降后上升的趋势；热历史条件对耐酸碱性的影响，主要是通过影响微晶玻璃的晶相的数目及微观结构决定的，随保温温度的上升，耐酸性先上升后下降，耐碱性不断增强；热历史
5、对显微硬度的影响，主要是通过影响主晶相析出的数目及微观结构决定的，随着保温温度的上升，显微硬度呈不断上升的趋势。 关键字关键字：微晶玻璃; 热历史; 分相; 析晶II Abstract Microcrystalline glass which is also called glass ceramic or crystallized glass，is the basis glass of a specific composition with a special heat treatment means, then in the glass phase generating tiny, unif
6、orm distribution of crystals and to obtain a mixture of crystalline and amorphous materials. The successful development of the microcrystalline glass has a very important practical and theoretical value. It helps make the relationship among glass transition, glass structure and performance better kn
7、own to people，pushes the development of glass science and opens up a new way of making crystal materials. In this experiment, using analytical grade calcium carbonate, aluminum oxide, magnesium carbonate and silica as the main raw materials, CaO-MgO-Al2O3-SiO2 system- glass is prepared by melting. F
8、irst, three formulas of different components are determined according to the theory of the composition and design of microcrystalline glass. By observing and analyzing the results of melting and differential thermal analysis, analyzing the crystallization results, the most suitable distribution of t
9、he ratio of the glass group for this experiment study was achieved, i.e. CaO25%，MgO15%，Al2O310%， SiO250%， Sb2O32%. CaO-MgO-Al2O3-SiO2 system glass under this formula at 850 was without crystallization phenomena, but its crystallization phenomena at about 1010 is obvious, crystalline phase precipitat
10、ed mainly pyroxene and diopside. According to the best composition of this experiment, seven different thermal history conditions are used for preparation of basis glass, namely: cooling in the water; air cooling over the iron plate; annealing at 650 for 10 hours; annealing at 700for 10 hours; annea
11、ling at 750for 10 hours; annealing at 800for 10 hours; annealing at 850for 10 hours. Test on the basis glass we got by the testing techniques DTA, IR, and SEM etc., and discuss the changes in crystallization kinetic parameters of CMAS system- glass in different thermal history conditions and the imp
12、act of split-phase on crystallization. Analysis results show that the CMAS-system glass of the same composition under different thermal history conditions, of which exothermic peak areas and peak heights are significantly different,their crystallization activation energies(E),crystalline indexes wer
13、e different also by varying the thermal history. Besides, with the annealing temperature increasing, the accumulation of new phase is becoming more dispersed, and droplet-like particles gradually connect in dispersed worm-like chain, and then tuck-up overlapping from each other. The changes of therm
14、al history conditions have an influence on SiO4 tetrahedron keys associating in glass. As the annealing temperature increases, Si-O-Si、Si-O- keys in associating SiO4 asymmetric telescopic vibration increase and associaion SiO4中 Si-O-ternary and flexural，decreasing after the first increase. At last,
15、in accordance with the differential thermal analysis results under different thermal historical conditions, let samples fully crystallize with heat preservation for 4 hours at their respective crystallization temperature. Then use the experiment methods such as XRD, SEM and infrared III spectrum ana
16、lysis, and find that due to the effects of different thermal historical conditions on this kind of microcrystalline glass, the host-crystal number increases as the insulation temperature rises，while the par-crystal number does not have the obvious change. Microcrystalline glass microscopic structure and the split-phase morphology of state have the succession. The split-phase morphology of state determines microcosmic structure and morphology
