烧结法制MgO-SiO_2-Al_2O_3-B_2O_3-KF玻璃陶瓷成分设计优化及显微析晶研究

通过烧结与水淬相结合的方法制备并系统探讨了MgO-SiO2-Al2O3-B2O3-KF玻璃陶瓷的显微析晶.研究表明：MgO-SiO2-Al2O3-B2O3-KF玻璃陶瓷的烧结收缩率与玻璃化及组分的析晶程度相关;析晶程度愈高,烧结坯愈致密;试样中成分配比愈接近云母晶体成分的原子比,玻璃陶瓷的显微析晶程度愈高;在烧结温度为1 000℃时,即开始出现析晶,到1 050℃时,析晶程度达到最高,继续提高烧结温度,显微析晶又发生重熔.     

梯温场中玻璃陶瓷定向析晶的过程及工艺

以析晶理论和热传导理论为基础，研究了梯温场中玻璃陶瓷定向析晶的过程和工艺，分析了梯温场主要工艺参数－温度梯度，析晶界面温度，热源升温速度，边界条件等对定向析晶的影响，研究结果对于制定定向析晶工艺，制备性能优良的定向析晶玻璃陶瓷有一定的意义。     

Na_2O对微晶玻璃装饰板烧结和析晶的影响

研究了Na_2O含量对CaO-Al_2O_3-SiO_2系统微晶玻璃装饰板析晶温度、析晶相,烧结收缩及表面气泡的影响。确定了合适的Na_2O含量及烧结温度范围。     

添加物对CaO—Al2O3—SiO2系统玻璃析晶性能的影响

借助ＩＲ,ＤＴＡ,ＸＲＤ及ＯＭ分析手段,研究了ＺｎＯ,Ｎａ２Ｏ对ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２系统玻璃析晶性能的影响。结果表明,随（Ｎａ２Ｏ＋ＺｎＯ）／（Ａｌ２Ｏ３＋ＳｉＯ２）的量比增大,玻璃结构由致密转向疏松,且不均匀性增加,析晶活化能下降。     

Na2O对微晶玻璃装饰板烧结和析晶的影响

研究了Ｎａ２Ｏ３含量对ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２系统微晶玻璃装饰板析晶温度、析晶相、烧结收缩及表面气泡的影响。确定了合适的Ｎａ２Ｏ含量及烧结温度范围。     

B2O3—Na2O—CuO系统玻璃析晶物相定量分析

在研究玻璃析晶时，往往要对玻璃样品析出的晶相进行定性定量分析，最常用和可行的方法是用Ｘ射线衍射方法对玻璃中的析出相进行定性、定量分析，本文应用标准曲线法、外推法和Ｋ值法对Ｂ＿２Ｏ＿３─Ｎａ＿２Ｏ─ＣｕＯ系统玻璃中的析晶相Ｃｕ＿２Ｏ进行了定量分析研究。     

Na2O—CaO—2P2O5玻璃的分相与析晶

借助扫描电镜、Ｘ－射线衍射、透射电镜等手段，对Ｎａ２Ｏ－ＣａＯ－２Ｐ２Ｏ５玻璃的结构与相变的关系进行了研究。研究结果表明：磷酸盐玻璃的分相和析晶与热处理的时间、温度有关，热处理的时间或温度不同，析晶与分析可以相互转化，适当的热处理温度和时间，有利于控制生物玻璃的活性。     

氧氟碲酸盐玻璃析晶性质的研究

以TeO2-ZnO-ZnF2系统为研究对象,采用差热分析计算分析了玻璃样品的析晶活化能E,并且得出了析晶速率k与温度的关系.结果表明,随着玻璃中氟化物含量的增加析晶速率提高,不利于实现热处理可控析晶过程,氟化物组分引入的含量对制备该系统透明玻璃陶瓷有很大的影响.     

Si3N4—MgO—CeO2陶瓷烧结过程中MgO的自动析晶

作者首次发现了Ｓｉ３Ｎ４－ＭｇＯ－ＣｅＯ２系陶瓷在烧结过程中玻璃相自动析晶这一独特现象。对于Ｓｉ３Ｎ４－ＭｇＯ－ＣｅＯ２系陶瓷在１４５０℃，ＭｇＯ－ＣｅＯ２就会与Ｓｉ３Ｎ４颗粒表面ＳｉＯ２反应形成硅酸盐液相，冷却后则成为玻璃相保留在烧结体中；当烧结温度高于１５５０℃时，作者发现，ＣｅＯ２仍留在玻璃相中，但ＭｇＯ会自动析晶出来，其结果是大大减少了烧结体中严重影响其高温性能的玻璃相的含量，对于提高烧结     

Influence of ZrO2 on sintering and crystallization of CaO-Al2O3-SiO2 glass-ceramics

ZrO2 was added into CaO-Al2O3-SiO2 glass-ceramics and the effect of ZrO2 on sintering and crystallization of CaO-Al2O3-SiO2 glass ceramics was investigated. The results show that the sintering shrinkage ratio of glass particles decreases with the increase of the content of ZrO2. ZrO2 has an unfavourable effect on sintering shrinkage ratio of glass particles. The sintering shrinkage ratio of glass particles increases with the increase of sintering temperature. The increase of sintering temperature favors the decrease of the liquid phase viscosity of glass particles. ZrO2 has little effect on crystallization of main crystalline phase （β-wollastonite）. However, it promotes the crystallization at relatively low temperature.     

CaO-Al2O3-SiO2系统微晶玻璃晶化行为的研究

以CaO-Al2O3-SiO2系统为基础玻璃,以粉煤灰为主要原料制得以透辉石(CaO@MgO@2SiO2)和钙黄长石(2CaO·Al2O3·     

Preparation and crystallization action of SiO2 -Al2O3 -CaO-ZnO-R2O porous glass-ceramics

Using powder-sintering method,SiO2-Al2O3-CaO-ZnO-R2O porous glass-ceramics were produced for analysis. Five samples with different SiO2 /CaO ratios were used in the research. The mechanical properties, microstructures and textures of porous glass-ceramics are investigated by using differential thermogravimetric analysis/differential thermal analysis ( TGA/SDTA) ,X-ray diffraction ( XRD) ,and scanning electron microsco- py ( SEM) . The activity energy of crystallization ( E) and crystallization kinetics parameter ( k) were calculated based on the modified JMA equation. The Avrami parameter n was obtained according to Augis-Bennett function. The results show that the k value of No. 1 sample ( SiO2 /CaO = 61∶ 18) is the largest among all samples, which tends to crystallize more easily,and crystallization processes of all samples are observed bulk crystallization. The main crystal phase observed is parawollastonite ( clinorhombic system) with puncheon shape. Poreforming agents decomposed at 100 - 500 ℃ form a large number of closed pores with micron dimension and several semi-open pores distribute uniformly in the glass-ceramics matrix. This work may be expected to be favorable for industrial scale applications of porous glass-ceramics in the field of building thermal insulation.     

CaO-Al_2O_3-SiO_2系统微晶玻璃晶化行为的研究

以CaO Al2 O3 SiO2 系统为基础玻璃 ,以粉煤灰为主要原料制得以透辉石 (CaO·MgO·2SiO2 )和钙黄长石 (2CaO·Al2 O3 ·SiO2 )、霞石 (NaAlSiO4 )为主晶相的微晶玻璃。用DTA、XRD和SEM等现代测试方法 ,研究了Fe2 O3 ,TiO2 ,Cr2 O3 对粉煤灰玻璃的晶化行为的影响。结果表明 :Fe2 O3 有利于形成尖晶石型MgFe2 O4 晶核剂 ,从而促进玻璃的微晶化。Cr2 O3 、TiO2 均是有效的晶核剂     

Effects of heat treatment temperature on crystallization and thermal expansion coefficient of Li2O-Al2O3-SiO2

The basic glass of Li₂O-Al₂O₃-SiO₂ system using P₂O₅ as nucleator was prepared by means of conventional melt quenching technology, and the heat-treatment process was determined by using differential thermal analysis. The crystalline phases and the microstructure of the glass-ceramics were investigated by using X-ray diffraction and scanning electron microscopy. The results show that the glass based on Li₂O-Al₂O₃-SiO₂ oxides using P₂O₅ as nucleator can be prepared at lower melt temperature of 1450°C and the glass-ceramics with lower thermal expansion coefficient of 21.6 × 10⁻⁷°C⁻¹ can also be obtained at 750°C. The glass-ceramics contain a few crystal phases in which the main crystal phase is β-quartz solid solution and the second crystal phase is β-spodumene solid solution. When the heat treatment temperature is not higher than 650°C, the transparent glass-ceramics containing β-quartz solid solution can be prepared. β-quartz solid solution changes into β-spodumene solid solution at about 750°C. And the appearance of the glass-ceramics changes from translucent, part opaque to complete opaque with increasing temperature.     

Pressureless reactive sintering mechanism of nanocrystalline Bi2O3-Y2O3 solid electrolyte

The nanocrystalline Bi2O3-Y2O3 solid electrolyte material was synthesized by pressureless reactive sintering process with Bi2O3 and Y2O3 nano mixed powder as raw materials, which was prepared by a chemical coprecipitation process. The study on the behavior of nano δ-Bi2O3 formation and its grain growth showed that the solid solution reaction of Y2O3 and β-Bi2O3 to form δ-Bi2O3occurs mainly in the initial stage of sintering process, and nano δ-Bi2O3 crystal grains grow approximately following the rule of paracurve ((D-D0)2=K.t) during sintering process. After sintered at 600℃ for 2 h, the samples could reach above 96% in relative density and have dense microstructure with few remaining pores, the δ-Bi2O3 grains are less than 100 nm in size.     

TiO2和Cr2O3复合晶核剂对微晶玻璃晶化行为的影响

通过差热分析、X射线衍射分析、偏光显微镜和扫描电镜观察等测试方法,研究了TiO2和Cr2O3作晶核剂对金属尾矿微晶玻璃晶化行为的影响,研究表明：Cr2O3和TiO2复合晶核剂能有效地促进CaO-MgO-Al2O3-SiO2系统玻璃在较低温度下即开始晶化,且形成以透解石为主晶相的微晶玻璃,晶核剂质量浓度不同对玻璃析晶的影响不同。     

Effect of nucleating agents on microstructure and mechanical properties of SiO2-Al2O3-ZrO2 glass-ceramics

SiO2-Al2O3-ZrO2 glasses with different nucleating agents were crystallized under special processing schedule. The microstructure and mechanical properties of the glass-ceramics in SiO2-Al2O3-ZrO2 system were investigated by differential scanning calorimetry, scanning electron microscopy, X-ray diffraction and three-point bending method. The results show that ZrO2 is not an effective nucleating agent in SiO2-Al2O3-ZrO2 system, while TiO2 is effective for the separation of spinel, and P2O5 facilitates solubility of ZrO2 in glass and crystallization. The main crystalline phases of the glass-ceramics are spinel, anorthite and tetragonal zirconia. With the increase of ZrO2 content in the glass, glass-ceramics show higher bending strength （120 MPa） than others.     

TiO_2和Cr_2O_3复合晶核剂对微晶玻璃晶化行为的影响

通过差热分析、X射线衍射分析、偏光显微镜和扫描电镜观察等测试方法 ,研究了TiO2 和Cr2 O3作晶核剂对金属尾矿微晶玻璃晶化行为的影响 .研究表明 :Cr2 O3 和TiO2 复合晶核剂能有效地促进CaO -MgO -Al2 O3-SiO2 系统玻璃在较低温度下即开始晶化 ,且形成以透辉石为主晶相的微晶玻璃 ,晶核剂质量浓度不同对玻璃析晶的影响不同 .