仿花岗岩微晶玻璃的制造及技术关键的探讨——仿花岗岩微晶玻璃的制造工艺

本世纪60年代后期,微晶玻璃的研究取得突破性进展,各种具优异性能的微晶玻璃制品开始工业化生产,一些国家的科研专家开始研究开发微晶玻璃饰面材料,如前苏联开发成功的“矿渣微晶玻璃”,捷克斯洛伐克以玄武岩作原料生产的“人造玄武岩”和美国开发成功的“人造蛋白石”等等。所有这些制品其理化性能都远优于天然石材,但没有天然石材那漂亮的外观花纹,很难作为天然石材的理想替代品。 到了70年代,日本电器硝子株式会社的科学家率先突破技术难关,研制出了具天然大理石外观且性能远优于天然石材的“结晶化玻璃大理石”,并于1974年开始工业化生产,商品命名为“新型玻璃大理石(Neoparies)”。     

钛酸铅微晶玻璃介电性能研究

主要对钛酸铅系铁电性微晶玻璃的介电性能做了研究,研制的微晶玻璃初始组成由形成主晶相的氧化物和形成玻璃相的氧化物构成,经过熔融、热处理可以得到以钛酸铅为主晶相的微晶玻璃,分析了不同组成情况下微晶玻璃的介电性能.     

微晶玻璃的玻璃相

微晶玻璃几乎都含有未结晶玻璃的残余,残余玻璃相的组成和体积分数取决于母体玻璃的组成与热处理制度。 残余玻璃相可能显著地影响到微晶玻璃的一些重要性质。例如,某些与离子穿过微晶玻璃结构的扩散性有关的及与微晶玻璃的粘滞流动有关的性质,都强烈地依赖于玻璃相的化学组成和体积分数。此外,微晶玻璃的机械强度、微裂纹增大方式、化学稳定性以及对可见光的透过度等也受到玻璃相的影响。     

纳米CdSe_xS_(1-x)微晶玻璃的光吸收性能

半导体纳米微晶掺杂滤光玻璃由于具有优异光学性质 ,近年来已成为光电子材料科学与技术关注的焦点之一。以硼硅酸盐玻璃为基质 ,通过对掺杂微晶组成、结构的设计以及颗粒尺寸的控制 ,系统的研究了纳米微晶的组成、结构以及纳米颗粒尺寸效应等因素对玻璃光吸收性能的影响。结果表明 ,玻璃吸收曲线的截止波长位置以及截止吸收系数主要取决于半导体纳米CdSexS1-x微晶的组成 ,吸收曲线的斜率取决于纳米微晶的颗粒尺寸分布     

微晶玻璃制作工艺

玻璃是一种无规则结构的非晶态固体。微晶玻璃是由特定组成的母玻璃在可控条件下进行晶化热处理,在玻璃基质上生成一种或多种晶体,使原来单一、均匀的玻璃相物质转变成了由微晶相和玻璃相交织在一起的多相复合材料。美国常将微晶玻璃称为微晶陶瓷,日本称为结晶化玻璃,我国多称微晶玻璃。     

矿渣微晶玻璃的制备及展望

本文介绍了制备矿渣微晶玻璃的方法-熔融法和烧结法，总结了两种方法各自的优缺点，综述了基础玻璃的组成和晶核剂对制备矿渣微晶玻璃的主晶相及性能的影响；从矿渣微晶玻璃现状出发，展望了矿渣微晶玻璃的未来发展。     

可切削微晶玻璃的研究现状及进展

可切削生物活性微晶玻璃是近年来新兴的一种生物材料，本文综述了可切削微晶玻璃的组成、结构、制备工艺、组成特性、生物活性评价及研究状况，并对可切削生物微晶玻璃的应用前景进行分析展望。     

可机械加工生物活性微晶玻璃的研究现状及进展

可机械加工生物活性微晶玻璃是近年来新兵的一种生物材料。综述了可机械加工微晶玻璃的组成、结构、制备工艺、组成特性、生物活性评价及研究状况．并对可机械加工生物微晶玻璃的应用前景进行了分析展望。     

矿渣微晶玻璃的制备及展望

介绍了制备矿渣微晶玻璃的方法-熔融法和烧结法，总结了两种方法各自的优点及存在的问题，着重综述了基础玻璃的组成和晶核剂对制备矿渣微晶玻璃的主晶相及性能的影响；从矿渣微晶玻璃现状出发，展望了矿渣微晶玻璃的未来发展趋势。     

硬盘用基板微晶玻璃的研究与应用

介绍了适用于高容量、小型化硬盘用基板的各种微晶玻璃材料,简要讨论了各种微晶玻璃的化学组成、显微结构、主晶相种类以及各种微晶玻璃的特性,并对今后的发展趋势进行了展望。     

CaZrTi2O7 zirconolite synthesis: From ceramic to glass-ceramic

The formation of CaZrTi₂O₇ zirconolite and its crystallization in sodium alumino-borosilicate glass has been investigated via sintering in air. The ceramic precursor is prepared using a soft chemistry route to ensure ultimate mixing of the reactants at the molecular level. A nearly phase pure CaZrTi₂O₇ zirconolite is formed after sintering the ceramic precursor at 1400°C for 12 hours. In order to form zirconolite glass-ceramics, various processing conditions are investigated including sintering temperatures, different glass composition precursors, and ceramic to glass weight ratios. Zirconolite crystallization on the surface and inside of glass-ceramic-pelletized samples is investigated. Higher ceramic to glass weight ratio leads to the formation of zirconolite as crystalline phase, which is quite dominant in glass.     

Sintering and properties of zircon ceramic with glass-forming additives

Conclusions The sintering and properties of a ceramic based on zircon with additions corresponding to eutectic mixtures of three-component glasses have been studied.The sintering of zircon with glassy additives is determined by the amount of the decomposed zircon and glass phase which forms in the specimen.It is shown that the most intense sintering and the greatest increase in the strength of zircon ceramic is produced by the addition of a calcium aluminosilicate glass.The relationship between the ultimate bend strength and the thermal-shock resistance of the zircon ceramic with glass additions, on the one hand, and the amount of glass phase formed in the specimens, on the other, has been established.Translated from Ogneupory, No. 4, pp. 47–52, April, 1979.     

Flaw Generation During Constrained Sintering of Metal-Ceramic and Metal–Glass Multilayer Films

Sintering of symmetrical multilayer films has been studied theoretically and experimentally. Experiments were conducted on ceramic/metal/ceramic and glass/metal/glass films. The sintering rate of free films was compared to the sintering rate of multilayers. The origin of processing flaws was examined. The following results were obtained: (1) Differential sintering rates of the components in the multilayer give rise to in-plane tensile and compressive stresses. The film that is stressed in tension in the early stage of sintering is most susceptible to fracture. Experiments with ceramic/metal/ceramic multilayer are in agreement with this prediction. (2) A theoretical prediction that the glass/metal/glass multilayer will not develop defects because of a high value of the shear relaxation factor in glass is confirmed by experiments. (3) The likelihood of developing a tensile stress in the multilayer depends only on geometry, the green density, and the ratio of the intrinsic sintering pressures. (4) The in-plane shrinkage of the multilayer depends on the difference in the free-sintering rates and the shear relaxation factors, and is reasonably well predicted by the analysis. (5) We have evidence that the metal layer deforms plastically when it is placed in tension by differential sintering.     

Phase evolution and microstructure analysis of CaZrTi2O7 zirconolite in glass

The internal crystallization of CaZrTi₂O₇ zirconolite in a sodium alumino-borosilicate glass has been investigated with powder X-ray diffraction (XRD), scanning electron microscopy and energy dispersion spectroscopy (SEM-EDS), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) techniques. The samples have been prepared using a soft chemistry route and ceramic phase evolution has been observed with sintering time. Zirconolite as the dominant phase at 1 h sintering gradually changes to baddeleyite structured materials for longer sintering times. XRD shows that one dominant phase belongs to zirconolite at 3 h sintering, however, SEM-EDS reveals that the dominant ceramic phase is actually baddeleyite phase, which is enclosed by zirconolite phase. TEM and SAED patterns also confirm the crystallization of zirconolite phase in glass. The addition of CaO enhances the formation of zirconolite (i.e. impedes baddeleyite phase) with CaO to glass weight ratio ≤ 35:100.     

BaO-Al2O3-B2O3-SiO2玻璃/SiO2高膨胀低温共烧陶瓷研究

用BaO-Al2O3-B2O3-SiO2玻璃与二氧化硅复合的方法制备了高膨胀系数低温共烧陶瓷。实验首先制备一组玻璃材料,通过热膨胀测试、DTA等方法研究了玻璃的热学性能,然后用玻璃与石英、方石英和鳞石英晶体按一定比例复合制得高膨胀低温共烧陶瓷。通过烧结试验、XRD等分析方法研究了复相陶瓷材料的烧结收缩性能、晶相组成、热膨胀系数和介电常数。结果表明:50%BaO-7.5%Al2O3-30%B2O3-12.5%SiO2玻璃具有较低的转变温度(520℃)。该玻璃与鳞石英晶体以1:1的比例复合,850℃/10min烧结可以获得热膨胀系数为12.18×10-6K-1、介电常数为5.37的低温共烧陶瓷。     

Recycle of Waste Glass into "Glass–Ceramic Stoneware"

The reuse of soda–lime–silica scrap or waste glasses as additives for traditional ceramics has been investigated extensively in the literature. Although interesting, this solution does not generally allow large quantities of glass to be recycled. This study reports a novel high glass recycle approach that replaces, in the formulation of porcelain stoneware, the feldspar flux with finely powdered glass derived from the melting of different waste products, e.g. lime from fume abatement systems, feldspar mining residues, and scrap soda–lime glass. At an optimized glass/clay ratio, the "glass–ceramic stoneware" samples sinter at 1000°C. The "glass–ceramic stoneware" has a bending strength approaching 90 MPa and a fracture toughness exceeding 2.0 MPa·m^0.5, similar to those of conventional porcelain stoneware, which requires sintering at higher temperatures. The high strength and fracture toughness are attributed to the interaction between the glass and clay residues upon sintering, which allows the development of several different crystalline phases.     

Fabrication of a Novel Calcium Carbonate Composite Ceramic as Bone Substitute

The coral, whose main composition is aragonite‐type calcium carbonate, has been widely used as bone substitute in clinic. However, the study on calcium carbonate bioceramic has not been largely reported due to difficulty in sintering calcium carbonate which is liable to evidently decompose at low temperature. In this study, a novel calcium carbonate composite ceramic was fabricated by sintering fast at a low temperature. A degradable, biocompatible phosphate‐based glass (PG) which grew liquid at a low temperature was added as sintering agent in the sintering process. The sintering schedule was explored by thermal analysis. The phase composition, microstructure, compressive strength, and biocompatibility of calcium carbonate composite ceramics were evaluated. The results revealed that the optimum holding time at the sintering temperature was 20 min. The obtained calcium carbonate composite ceramics did not produce calcium oxide but new compounds according to phase analysis. The compressive strength of calcium carbonate composite ceramics correspondingly increased with growing addition of PG ranging from 10 to 50 wt%. The cell proliferation on the calcium carbonate composite ceramic was not compromised but augmented compared to the neat calcium carbonate ceramic without adding PG as sintering agent. The novel calcium carbonate composite ceramic is a promising bone substitute for bone defects.     

Cofiring Kinetics and Mechanisms of an Ag-Metallized Ceramic-Filled Glass Electronic Package

Cofiring kinetics and mechanisms of an Ag-based ceramic-filled glass packaging system have been investigated. Boundary diffusion controlled solid-state sintering is identified as the controlling densification mechanism of the Ag film. For ceramic-filled glass tape, which is a mixture of glass and ceramic powders, the sintering kinetics are controlled by the viscous flow of low-softening-point glass. With the densification results of Ag film and ceramic-filled glass tape, the camber development during cofiring of a two-layerd structure of Ag film/ceramic-filled glass tape can be theoretically predicted by viscous analysis, which also agrees well with experimental observations.     

Laser sintering of carbon nanotube-reinforced ceramic nanocomposites

The fabrication of carbon nanotube (CNT)-reinforced ceramic nanocomposites through laser sintering has been rarely studied, and the fabrication feasibility has been rarely tested. Laser sintering is a flexible, localized and high-precision process, which can also potentially produce coatings or parts with complicated shapes and/or spatially controlled compositions. Therefore, compared with other technologies laser sintering has its own advantages. Experimental investigations reported in this paper have confirmed the feasibility of fabricating CNT-reinforced ceramic nanocomposites through laser sintering of ceramic nanoparticles and CNTs. The studies show that laser sintering can induce the agglomeration of ceramic nanoparticles into a relatively more continuous ceramic phase, and during the sintering process CNTs are well preserved without any obvious quality degradation, and they are also bonded with the ceramic phase after laser sintering.     

Matching correlation study of titanium-based ceramics with glass based on dissolution characteristics

Glass-ceramics are ideal candidates in Low-temperature Cofired Ceramic (LTCC) technology. The “dissolution-precipitation” mechanism ensures the sintering compactness of glass-ceramics at low temperatures. The ceramics must be dissolved and precipitated in the liquid phase with the assistance of glass additives. In this case, the characterization of dissolution behaviors that should be highly valued has rarely been emphasized. This study puts forward a simple, repeatable, and efficient design for characterizing the dissolution behaviors of several titanium-based ceramics in glass frits under variable temperature conditions. Interestingly, a glass frit with good wettability does not ensure the low-temperature sintering process of a ceramic matrix. In contrast, the dissolution characteristics of ceramics in the glass should be seriously considered. Hopefully, the study of dissolution behaviors could strengthen the fundamental understanding of the low-temperature sintering of ceramics and offer a glass-ceramic design strategy for developing high-performance.