Evaluation of Corrosion Resistance of Refractory Materials in Furnaces for Melting Frit Glazes

The corrosion resistance of refractories to frit melts applied at the Velor Nompany (city of Orel) are investigated. Based on the results of the study, it is proposed to replace the refractory MKS, which is currently used in furnaces for melting frit glazes, by the refractory material KMTs that is more resistant to frit melts.     

过滤用玻纤复合针刺毡的研发

介绍了玻纤针刺毡的概念、特点及加工工艺。着重介绍了新型过滤材料一玻纤复合针刺毡的原料选择和加工工艺的确定。     

高档卫生洁具釉用熔块的研制

主要介绍了高档卫生洁具釉用熔块的技术路线及过程研制。重点研究了原料质量控制、熔块工艺流程、熔块在釉中实验及坯釉结合性能等，并对结果进行分析，最后提出了生产过程中的具体建议。     

Glass enamel for steel based on diatomite material

The possibility of replacing quartz sand for melting enamel frit by natural diatomite rock is investigated. It is established that the use of local diatomite as the silica material in melting enamel frits is a promising trend in enameling technology. The properties of frits based on diatomite materials are similar to the properties of the reference low-melting frit F-1; they have have slightly lower softening and melting temperatures, and their technological characteristics are within the limits specified by GOST 24495-80 for undercoat enamel on steel. __________ Translated from Steklo i Keramika, No. 5, pp. 36–37, May, 2006.     

Current trends in the development of organosilicon coupling agents for fiberglass

Current trends in the consumption of silane fibers by fiberglass manufacturing companies are discussed. New brands of organosilicon coupling agents offered by the leading world producers are described. The possibility of using silanes with different functional groups in the production of fiberglass materials with improved consumer properties is investigated. Translated from Steklo i Keramika, No. 7, pp. 18 – 21, July, 1999.     

Characterization of Compostability and Mechanical Properties for Linseed Oil Resin Composites Reinforced with Natural Fibers

This work characterizes biodegradation behavior and mechanical properties of fiber-reinforced composites made from renewable sources. A linseed oil-based thermoset is used as the polymer matrix. Bamboo, cotton, hemp and fiberglass are used as the reinforcing fibers. Although tensile properties of comparable material systems have been reported in literature, characterization of their compostability has not been studied. Our experimental results show that the natural fibers degrade well under controlled composting conditions, whereas the thermoset polymer matrix did not. Tensile properties of the material are improved significantly with fiberglass reinforcement, whereas the natural fiber reinforcement is able to enhance the material's ductility.     

玻璃纤维涂层织物的技术与应用

玻璃纤维涂层织物是在玻璃纤维织物表面涂覆一层涂层材料,不仅可以充分发挥玻璃纤维固有的性能特点,还可以赋予织物新的性能,以满足不同应用领域的需求。介绍了各种涂层材料的特性、各种涂覆工艺的特点及涂层织物的应用情况。     

高效空气过滤用PTFE膜材料的结构和性能

聚四氟乙烯(PTFE)膜高效空气过滤材料以其过滤效率高、初始阻力小和无硼释放等优点,在电子工业洁净室中得到了广泛的应用,然而目前尚缺乏PTFE膜与传统滤材结构及性能的系统对比研究。本文选取了两种商业应用的PTFE膜高效滤材,采用扫描电子显微镜、孔径分析仪、自动滤材测试仪等多种表征手段对材料的微观结构和过滤性能与超细玻璃纤维(简称玻纤)滤材进行了较为全面的对比研究,结果表明,PTFE膜本质上也是一种纤维类滤材,其纤维平均直径为60～85nm,远低于玻纤滤材的668.8nm;高效PTFE膜的过滤效率与玻纤滤材相当,且其初始阻力不及玻纤滤材的50%,但PTFE膜滤材的容尘性能不及玻纤滤材,更适合应用于有再生或预过滤装置的场所。     

Influence of crystallization inside glass frit on seal stress in ceramic metal halide lamps

Ceramic metal halide lamps use polycrystalline aluminum oxide as an arc tube material; cracks inside the glass frit—used as the seal material—have been known to occur occasionally. This study measured the stress on the lamp seals caused by changes in the cooling rate during the sealing process by a 2D stress measurement method. Seal stress decreased with reducing cooling rate. Therefore, we discuss the influences of the glass frit's microstructure and the coefficients of thermal expansion (glass frit, capillary, and Nb wire) on the seal stress. The coefficient of thermal expansion of the annealed glass frit was essentially closer to those of the capillary and Nb wire, while that of the rapidly cooled glass frit differed greatly. Moreover, the glass frit of the rapidly cooled lamp seal contained only an amorphous phase (Dy, Si, Al, and O), while the glass frit of the annealed lamp seal contained both an amorphous phase (Dy, Si, Al, and O) and a crystalline one (Dy₂SiO₅ and Al₂O₃). Fracture toughness was found to be larger in the crystals than in the amorphous phase area. Moreover, it was larger in the area where crystalline Dy₂SiO₅ and Al₂O₃ were present compared to the area where only crystalline Dy₂SiO₅ was present.     

Modeling Particle Penetrations Through Wall Assemblies Using Computational Fluid Dynamics

Outdoor particles can penetrate through wall assemblies and influence the indoor air quality (IAQ). In this study, a computational fluid dynamics (CFD) model was developed for predicting the particle penetration through wood-framed residential wall assemblies. The model included a simplified approach to account for the particle loss due to the fiberglass insulation material layer in the wall assemblies. Particles ranging from 0.001 to 10 μm in diameter were studied. Particle movement was modeled following an Eulerian approach, while particle deposition in the fiberglass insulation was accounted for by an additional sink term in the governing equation, derived from the classical filtration theory. The model was applied to a typical residential wall assembly, assuming crack heights of 1 mm in the vertical direction and 3 mm in the horizontal direction and a fiberglass insulation width of 0.14 m. The results showed that 0.05–1 μm particles were the most penetrable particles. The fiberglass insulation media reduced the particle penetration by more than 85% when the air permeability of the fiberglass insulation was larger than 0.001 s.

Copyright 2015 American Association for Aerosol Research     

玻璃钢复合材料灯架的分析与制作技术研究

介绍了玻璃钢复合材料的性能,并用大型结构分析软件ANSYS对一个玻璃钢复合材料制作的信号灯架进行了有限元分析,与普通钢材信号灯架进行了分析和比较.介绍了玻璃钢信号灯架的制作方法,强调以玻璃钢材质取代普通钢材,符合保护环境资源的目的.     

Processing and properties of glass-bonded silicon carbide membrane supports

Porous SiC membrane supports were fabricated from SiC and glass frit at a temperature as low as 850 °C in air by a simple pressing and heat-treatment process. The effects of the initial SiC particle size and frit content on the porosity, flexural strength, and air permeation of the membrane supports were investigated. During heat-treatment, the glass frit transformed to a viscous glass phase, which acted as a bonding material between SiC particles and as a protecting layer for severe oxidation of SiC particles. The porosity of the porous SiC membrane supports could be controlled within a range of 37–46% with the present set of processing conditions. The typical flexural strength, permeability, and specific air flow rate of the porous membrane supports fabricated using 23 μm SiC particles with 15 wt% glass frit were 75 MPa, 4.2 × 10⁻¹³ m², and 32.4 L/min/cm², respectively.     

氧化锌和铅硼玻璃料对MgTiO3微波介质陶瓷的影响

研究了氧化锌和铅硼玻璃料的加入对MgTiO3微波介质陶瓷的烧结和微波介电特性的影响。结果表明：氧化锌和铅硼玻璃料均可以使MgTiO3微波介质陶瓷的烧结温度降低，在等量添加的条件下，铅硼玻璃料降低烧结温度的效果更佳，可使烧结温度降至1200℃，且器件在2－6GHz的频率范围内具有良好的介电性能。     

环保型晶雕堆花装饰在高档骨质瓷中应用的研究

文中简要介绍了高档骨质瓷晶雕堆花装饰的特点,通过实验研究获得了适合晶雕堆花装饰的骨质瓷无铅坯釉配方,开发出了用于骨质瓷晶雕堆花装饰的无铅干粒釉和釉膏,介绍了高档骨质瓷晶雕堆花装饰的加工工艺过程。     

Evaluation of pyrolysis parameters for fiberglass reinforced polymer composites based on multi‐objective optimization

This study was conducted to investigate the ability of global, multi‐objective/variable optimization methods to estimate material parameters for comprehensive pyrolysis models—thermo‐physical and optical properties of two fiberglass reinforced polymer (FRP) composites that share the same fiberglass. With these optimization methods used in pair with a comprehensive pyrolysis model, parameter estimation was carefully conducted with considerations given to applying appropriate thermal decomposition kinetic models (three different models from simple to complex) and optimization targets (cone calorimeter data irradiated at 50 kW/m²). Estimation results are compared with independently measured effective properties—thermal conductivity, specific heat capacity, and emissivity of polymer resins and FRPs. Additionally, fiberglass properties estimated from the two FRPs are compared to analyze for consistency in optimized values. The results show that for a well‐configured parameter estimation exercise using the optimization method described earlier, (1) estimated results are within ±100% of the measurements in general and sometimes comparable to effective property values, (2) increasing complexity of the kinetic modeling for a single component system has insignificant effect on estimated values, and (3) increasing complexity of the kinetic modeling for a multiple component system with each element having different thermal characteristics has positive effect on estimated values. Copyright © 2014 John Wiley & Sons, Ltd.     

Isothermal corrosion testing of frit furnace refractories

In this paper, the corrosion behaviour of aluminosilicate type refractories in frit melts is studied in an isothermal corrosion test setup. A refractory brick of largely andalusite and sillimanite composition was compared to another refractory brick of mullite and sillimanite composition, both of which were made by different manufacturers for use in different frit furnaces. The industrial frit used for corrosion tests was a commercial product used in a wall tile glaze formulation. Corrosion tests conducted under isothermal conditions provide quantitative and reproducible data about the corrosion performance of refractories. In this study, tests were performed by partially immersing a 15 mm × 15 mm × 115 mm refractory specimen into a frit melt at temperatures between 1404 and 1504 °C. The effects of temperature, duration of exposure and the refractory brick type were investigated using a statistically designed set of experiments. The ANOVA (analysis of variance) table indicated that temperature and test duration were the most important factor effects, as expected. Increasing both temperature and exposure duration led to an increased amount of corrosion as measured by the cross-sectional area loss of the corroded refractory specimen. Postmortem microstructural analysis was also done on the specimens, with extensive amount of ZnO·Al₂O₃ precipitation observed along the frit–refractory interface, where crystals of mullite and alumina were also found to precipitate. Increasing the amount of exposure time and temperature produced more ZnO·Al₂O₃ precipitation. As identified by SEM-EDS analysis, mullite crystals were in the needle-like morphology, while alumina crystals were generally cubic. Additional experiments were conducted by rotating the specimens in the melt at 50 rpm of rotational speed. Due to the reduction of boundary layer thickness, more dissolution was observed from the rotated specimens. In all specimens, corrosion was more pronounced in the bond phase than through the large filler grains of mullite and andalusite.     

Middle- and high-permittivity dielectric compositions for low-temperature co-fired ceramics

Various middle- and high-permittivity dielectric material systems for LTCC were examined. By designing several borosilicate glass frit systems carefully, we tried to lower the temperature of densification to 875 °C in selected host dielectric materials still maintaining acceptable dielectric properties. The effects of glass addition on the densification, electrical properties, and phase changes in the host dielectric materials were examined.     

Preparation and mechanical properties of thick interlayer composites

A technique is described for producing a thick interlayer composite material composed of an epoxy resin as the matrix and an acrylic-coated fiberglass filler. Through the use of electrostatic forces, the fibers are encapsulated with a controlled, uniform layer(s) of the rubbery acrylic polymer. This coating is then crosslinked. These fibers are subsequently placed into the epoxy matrix, whereby the interfacial properties of the composite become modified. Rapid diffusion of the resin and curing agent results in an interpenetrating network being formed at the glass-epoxy interface. The placement of a uniform latex coating on the fiberglass surface results in improvements in the mechanical properties of the composite. Increases in damping, impact strength, and tensile properties are described.     

Strong Sintered Miserite Glass-Ceramics

Strong and tough glass-ceramic materials based on the complex chain silicate miserite (KCa₅open square(Si₂O₇)(Si₆O₁₅)F) have been prepared using standard frit sintering and internal nucleation processes. The miserite may be accompanied by crystals of fluorite, cristobalite, xonotlite, a canasite-like phase, and fluorapatite. The highly crystalline glass-ceramics have a microstructure composed primarily of interlocked, lath- or log-shaped miserite crystals with pronounced cleavage planes. This microstructure provides abraded flexural strength values as high as 235 MPa (34 000 psi) and fracture toughness values >3.0 MPa·m^1/2. These strength and toughness values are quite high for a glass-derived material. Miserite glass-ceramics may be useful for many applications in which such strength and toughness are desired.     

Life cycle assessment of a ceramic glaze containing copper slags and its application on ceramic tile

Even though copper slags have many possible applications, their disposal is still practiced, creating long-term waste management problems. This led to the investigation of new products for residential applications, taking advantages of the interesting chemical properties of copper slag. This study aims to assess the environmental impact of the use of copper slag as secondary raw material in a ceramic glaze composition and to compare it with a traditional glaze. A manufacturing process was designed, through an industrial scale up operation from experimental laboratory data and the entire life cycle of the products was analyzed using the Life-cycle assessment (LCA) methodology. Considering the production of a ceramic glaze containing copper slag, the most impacting process resulted the one related to frit production, due to the large amount of thermal energy necessary for the raw materials melting. The comparative LCA analysis carried out between the frit obtained from metallurgical slags and a traditional one, demonstrated that the innovative ceramic frit has a greater environmental advantage. The LCA analysis allowed to highlight the most impactful stages of an industrial process using copper slag as a secondary raw material for glaze production and to quantify the potential environmental advantages of this operation.