烧结法微晶玻璃的研究

本文以增加玻璃比表面积和表面缺陷来降低晶体成核位垒为理论，通过烧结法试制微晶玻璃，将其用于建筑装饰，降低了微晶玻璃的生产成本。试验所用工艺的前半段为玻璃工艺，后半段为陶瓷工艺。所试制的样品经检测，其理化性能都优于陶瓷墙地砖和天然石材。     

烧结法微晶玻璃大理石的研制

本文利用天然矿物原料,采用烧结法制备具有结晶花纹,透明度高的微晶玻璃大理石,探讨了玻璃的熔制,碎玻璃的烧结等工艺,指出了合理的配方组成和适宜的玻璃颗粒组成是制造微晶玻璃大理石的关键。     

烧结法微晶玻璃的退火及缺陷

通过实验研究及工业生产分析,探讨了微晶玻璃装饰板材中的表面“裂纹”、“翘板”等缺陷产生的原因及与退火制度的关系,结合烧结法的工艺特点,提出避免退火过程中产生以上缺陷的较佳退火工艺制度。     

烧结法微晶玻璃着色工艺探讨

介绍了烧结法微晶玻璃装饰板的着色工艺,并结合实践对此作了简要评述。     

烧结法微晶玻璃着色工艺探讨

介绍了烧结法微晶玻璃装饰板的着色工艺,并结合实践对此作了简要评述。     

烧结法微晶玻璃中气孔的产生与消除

通过对微晶玻璃装饰板材工业化生产中,气孔产生过程和原因的研究,分析了烧结过程、晶化过程、熔制过程以及杂质、气氛等对气孔产生过程的影响,并提出相应的消除办法。     

烧结法微晶玻璃装饰板材的研制

用烧结法生产工艺成功地研制出规格为300×300mm、400×400mm、400×600mm、400×900mm,厚度为8～15mm的微晶玻璃装饰板材,其理化性能达到或超过天然花岗岩。本文用XRD和SEM研究了玻璃的析晶类型和形貌,讨论了影响工艺过程的诸因素。     

一次烧结法生产微晶玻璃饰面材料

利用废钢渣与玻璃粉一次性烧结法生产彩色微晶玻璃饰面材料，具有设备投资小、能源消耗少、原料来源丰富、成本低、有利环保等优点。本文简要介绍了研制过程和产品性能。     

烧结法钠长石微晶玻璃的节能研究

采用传统熔融法研究了以湖南衡山钠长石为主要原料,能在1300℃以下得到合格玻璃,烧结法制备β-CS为主晶相的建筑微晶玻璃的配方:钠长石与石英的最佳比例是100:26,由以上原料引入的玻璃成分质量分数为75%,其它原料引入的玻璃成分质量分数为25%;通过DTA和梯温炉实验等分析手段确定了玻璃热处理优化条件:核化温度/时间是820℃/1h,晶化温度/时间是1020℃/1.5h;利用X-射线衍射仪分析了晶化样品的主晶相为β-CS及其固溶体;测试了热处理后样品的理化性能达到或超过市场产品的性能;估算的综合能耗可比目前工业产品降低9%～11%。     

烧结法钠长石建筑微晶玻璃的研究

根据湖南衡山钠长石的物理化学性能特点,以衡山钠长石为主要原料,采用熔融烧结法成功地研制出微晶玻璃制品,其理化性能测试结果达到或超过天然花岗岩。用XRD研究了玻璃的析晶类型,讨论了影响工艺过程的主要因素。     

Study on sintered glass ceramics from Nb-Ta tailings

In this paper, particle sintering technology was used to transform tantalum niobium tailings (Nb-Ta tailings) into glass ceramic products. CaO, ZnO and BaO were used to adjust the composition of the glass. β-wollastonite was found as the major crystalline phase in all treated samples. With the CaO increasing, the intensity of crystal diffractive peaks is also increasing. The formation of β-wollastonite crystal can be accelerated by the increasing of CaO. The sintering is processed under the participation of liquid phase, and the increase of sintering temperature does a great favor on descending the liquid phase viscosity of glass particles, which consequently is available for sintering. The density and sintering quality of the samples prepared by two-step sintering are higher than that of one-step sintering. As the sintering temperature increases, the surfaces of the samples become better and have beautiful luster.     

如何获得更佳熔体流动指数检测结果

熔体流动指数测试广泛用于塑料工业的不同领域。难度在于,任意两个实验室可以轻易得到不同的检测结果,难以确定一种材料是否满足希望的熔体流动指数要求。为什么会出现这种差别,下文将对其原因进行分析,同时介绍如何解决这种差异。     

Permeability to water of sintered clay ceramics

The microstructural characteristics of sintered clay ceramics depend mainly on the clay type and thermal transformations. Different pore morphology and connectivity change the liquid water flow process through the material, as in the case of roof tiles which are progressively saturated with water during rain. In this study, 2 clays mined in Burkina Faso are used for manufacturing roof tiles. The major phases detected by X-ray diffraction in the two clays are kaolinite, illite, smectite, quartz and feldspar.The thermal behavior of clays by DTA and TG between 25 °C and 1100 °C is mainly related to individual roles of clay minerals. During sintering, dilatometry curves show successive densification stages in variable temperature ranges, as a function of clay mineral fractions in compositions. It explains differences in microstrutural characteristics and pore structure.The simulation of the capillary absorption of water uses the Sharp Front model. The interesting feature of this approach is that measurement of the data for the model requires no complex equipment. Only the Darcy permeability of the material and the steady state capillary pressure are necessary. Results evidence the strong difference of water absorption rates in the 2 clay ceramics, whereas they present similar porosity. It confirms the importance of pore morphology and connectivity in ceramics, induced mostly by the clay type and the sintering process.     

Some properties of sintered ceria ceramics

Conclusions Sintering of finely dispersed ceria occurs intensely in the 1300–1500°C range.In an atmosphere of inert gas and in vacuum the sintered CeO₂ is reduced with changes in crystal structure, which is accompanied by a reduction in the refractory and thermomechanical properties of the material.Unreduced CeO₂ is a highly refractory material which in oxidizing conditions can be used at temperature above 1900°C.     

On a way to material models for ceramics

This paper presents different probabilistic models which are based (i) for monophased materials on closed random sets (RACSs) and space tessellation such as Voronoi, Johnson-Mehl or Poisson mosaic, and (ii) for polyphazed materials on topologically closed random sets such as Matheron's Boolean model, dead-leaves model, tessellation of polyphazed structures and Stienen's model. Examples are given in both cases, such as UO₂, Fe–Ag, TiC–Co, WC–Co, concrete…     

Joining of sintered SiC ceramics at a lower temperature using borosilicate glass with laser cladding Si modification layer

The silicon carbide whose surface had been modified by laser cladding silicon layer was soldered by borosilicate glass. And the borosilicate glass solder had a thermal expansion coefficient similar to that of the silicon carbide substrate. The laser cladding silicon layer significantly improved the wettability between molten glass solder and silicon carbide and could reduce the soldering temperature. A sandwich-like joining structure (SiC/Si/solder/Si/SiC) was made after the borosilicate glass slurry put on the laser cladding silicon layers. The microstructure, compositions, and interfacial properties were studied. Results showed that good adhesion between silicon carbide and the glass soldering layer was achieved. The flexural strength of the connection structure prepared at 900 °C in the air reached 110 MPa. This research provides an effective technical solution for realizing local heat treatment soldering of large silicon carbide components.     

Structural and electrical properties of sintered zinc-titanate ceramics

The aim of this work was an investigation of structural and electrical properties of sintered zinc-titanate ceramics obtained by mechanical activation. Mixtures of ZnO and TiO₂ were mechanically activated in a planetary ball mill up to 90 min and sintered isothermally in air for 120 min at 1100 °C. The phase composition in the ZnO–TiO₂ system after milling and sintering was analyzed using the XRD method. Microstructure analyses were performed using SEM. The results of electric resistivity, capacitance and loss tangent of the sintered samples were obtained. The existence of zinc-titanate as a dielectric was proved (?_r = 12.5, Q = 386.1, tgδ = 0.0026, ρ = 1.02 Ωm).