International Journal of Applied Glass Science最新文献

This study presents the development of multicomponent glasses for glaze layers for dental yttria-stabilized tetragonal zirconia (Y-TZP). The samples were melted in the temperature range of 1 250–1 400°C and were cast in water to obtain a frit. The frits were grounded to a powder with a particle size of less than 40 µm. To study the crystallization tendency of melted glasses, they were thermally treated at 800°C and X-ray diffraction analyses were performed for both types of samples. The structure of the glasses was investigated by the Fourier-transform infrared spectroscopy. The thermal expansion coefficient, CTE, the glass-transition temperature, T_g, and the softening temperature, T_s, were defined. To test the glaze layer on zirconia ceramic, glass powders with different compositions were mixed with modeling fluid and applied on zirconia specimens and then fired at 800°C in a vacuum dental furnace. Scanning electron microscopy, SEM, was used to observe a cross-section of the glass–ceramic contact on a glazed zirconia ceramic specimen. Glass with the highest content of alkaline oxides is characterized by the closest CTE to zirconium ceramics (10.10⁻⁶ K⁻¹), the greatest transparency and good fluidity, and shows good adhesion to the zirconia. The glaze layer is homogeneous without cracks, pores, and crystals.

Contact damage of glass is one of the most crucial issues for glass products. To develop strong and tough glass products and to compare damage resistance among glass compositions, a simple method for evaluating the mechanical response of glass during contact is required not only for glass mechanists but also for glass customers and suppliers. Although it is well known that the quasi-static Vickers indentation test is one of the simplest and most useful methods to evaluate hardness and brittleness in glass, the indentation response of glass under the indenter at higher impact velocities remains to be quantitively understood because of the difficulty of measurement and limited experimental works. In this study, therefore, the dynamic indentation behavior of soda-lime glass is evaluated by using a lab-made free-drop indentation set-up with the coils for detecting electromotive forces (EMFs). The cono-spherical indenter made of tungsten carbide attached with a neodymium magnet was employed to generate the EMFs when the indenter passed through the coils located near the glass sample. The impact load versus indentation depth curve during the impact within a few tens of microseconds was successfully obtained both for an elastic contact and for an inelastic contact. Under an elastic condition, where no residual indent nor any cracks were left on the glass surface after the test, it is confirmed that there is almost no hysteresis in the impact load versus indentation depth curve and that the curve can be reproduced by the Hertzian analytical solution. Under an inelastic condition, on the other hand, it is found that the hysteresis in the impact load versus indentation depth curve stems from inelastic phenomena, such as plastic deformation (shear flow and/or permanent densification) and cracking. These results suggest that the dynamic indentation technique based on electromagnetic induction phenomena is a useful and effective tool for evaluating the mechanical responses of glasses during the impact.

Ni²⁺-doped glass–ceramics containing Zn(Ga_xAl_x−1)₂O₄ crystals were successfully synthetized using both parent glass crystallization (Technique 1) and a direct doping method also called “frozen sorbet” (Technique 2) to get a ZnGa₂O₄ crystal/glass composite. The frozen sorbet technique allows the survival of ∼10 nm crystalline particles. Both materials are further crystallized near their respective temperature of crystallization to get glass–ceramics with the stabilization of Zn(Ga_xAl_x−1)₂O₄ crystals. Although these two materials exhibit the same glass transition temperature, a shift in the crystallization temperature is observed. The glass–ceramics are transparent in the near infrared range, and the Ni²⁺ doping provides a broadband emission centered around 1300 nm with a full width at half-maximum (FWHM) equal to 228 nm. The structure, microstructure, and thermal and optical properties of these materials are discussed in the present study.

As a fission product in high-level radioactive nuclear waste, Mo has low solubility in borosilicate glass. Fe₂O₃ is not only a prevalent transition metal element but also a major corrosion product in high-level radioactive nuclear waste. Against this backdrop, the effect of Fe₂O₃ content on the structure and chemical durability of typical molybdenum-containing sodium borosilicate glasses for nuclear waste immobilization are studied. The results show that the samples containing more than 3.85 mol% Fe₂O₃, a completely homogenous amorphous glass sample is obtained. Moreover, the mechanism of the effect of Fe₂O₃ on the solubility of Mo is discussed in detail. In this work, a portion of Fe³⁺ is reduced to Fe²⁺ and enters into the glasses as a charge compensation ion as Fe²⁺O₆. Concurrently, Fe³⁺ ions contribute to the formation of the glass networks as Fe³⁺O₄. Iron incorporation can improve the chemical durability of the sample.

The structure of lithium bismuth borate glasses in the compositional series xBi₂O₃–25Li₂O–(75 − x) B₂O₃ was studied with the use of Raman and infrared (IR) spectroscopies. Transparent glasses formed between x = 0 and 55, whereas glass–ceramics formed between x = 60 and 75 mol% Bi₂O₃. Structural investigation on the borate network showed that the glasses were undermodified at high Bi₂O₃ compositions with metaborate, pyroborate, and orthoborate triangles and tetrahedra being present past the stoichiometric orthoborate compositions (O/B = 3). Bi₂O₃ was found to participate in the glass as both a network former and modifier, as observed in the Raman and IR spectra. Optical absorption spectra of the glasses show a redshift of the absorption edge with increased Bi₂O₃. Optical, thermal, and physical properties of the glasses were examined and correlated to the structural evolution.

This article delves into the significance of glass packaging in the European container glass industry's sustainable development, emphasizing its role in achieving key UN Sustainable Development Goals (SDGs). Covering health benefits, sustainable consumption, climate action, and collaborative partnerships, the European container glass industry's commitment to a circular economy and carbon neutrality by 2050 is explored. The discussion encompasses the industry's advancements in circularity and the critical transition to green energy. The article highlights the industry's strides over the past 50 years and outlines its vision for a sustainable future. It also points to the role of a supportive policy and legislative framework in enabling a circular and climate-neutral economy.

The glass industry is a significant source of greenhouse gas emissions due to its energy consumption profile and the use of fossil fuels in the manufacturing process. Most of the energy to produce glass is consumed in the process of treating raw materials to elevated temperatures, usually above 1500°C. Glass manufacturing also generates significant environmental impacts, such as greenhouse gas emissions, air pollution, water consumption, and waste generation. Therefore, improving the sustainability of glass manufacturing is a significant challenge for the industry and society. There are ways to reduce the energy consumption and emissions of glass melting, such as recycling glass, using oxy-fuel burners, improving furnace insulation and design, and adopting electric melting technologies. These methods can help save energy, lower costs, and enhance the sustainability and environmental footprint of the glass industry. However, the industry faces challenges and barriers, such as technical feasibility, economic viability, capital investment, and market acceptance. More research and development must be invested to improve the energy efficiency and environmental performance of glass melting. The objective of this paper is to provide an overview of the growth glass industry has made over the past 30 years and the remaining challenges for sustainable glass manufacturing with a focus on the fiberglass segment. Sharing of procedural methods, technical approaches, and results can help enable the global glass industry in our future sustainability challenges. The fiberglass segment included a broad technical view including glass chemistry development, product development, new industry codes and standards, melting development, computational fluid dynamic modeling, life cycle assessments, and sustainability goals linked to capital planning. The net result delivered a significant reduction in environmental emissions at the global enterprise scale. The implemented changes have taken decades, significant investments, and resources to plan and develop. Practices reviewed and implemented can help drive collaboration and commonality within the glass industry to achieve sustainability goals. Action is needed now if the glass industry is to meet global government demands of reducing carbon emissions by 55% by 2030 and zero carbon emissions by 2050 in alignment with the Paris Agreement on decarbonization.

Glass and glass ceramics are very functional materials, albeit their structural complexity. Their relevance ranges from fundamental science problems in the fields of physics, chemistry, and geoscience, to applications in health areas, engineering, or technological matters that require high performance. Enhancing our understanding of these materials' performance and refining sample preparation methods remains paramount in this field. Synchrotron facilities offer a suite of powerful techniques for the detailed characterization of glasses and glass ceramics. These methods provide valuable insights into their atomic and molecular structure, phase transformations, mechanical behavior, and thermal properties, ultimately contributing to the development of improved materials for a wide range of applications. In-depth investigations conducted under extreme conditions of pressure and temperature have yielded pivotal insights into densification mechanisms, phase transitions, crystallization kinetics, and their consequential macroscopic properties. The emergence of fourth-generation synchrotrons brings in a wave of novel experimental possibilities that may exert a profound influence on this field in the coming decade. In this study, we unveil a selection of the remarkable capabilities now accessible to researchers at the Brazilian Synchrotron Light Source—Sirius, within the realm of extreme methods of analysis (EMA) beamline for investigating vitreous systems under extreme conditions.

Contactless hot embossing has been demonstrated to possess the potential for cost-effective production and precise mounting concepts in fabricating glass microlenses and microlens arrays due to the reduced difficulty of mold fabrication and the possibility of obtaining self-aligned assemblies. This study aims to provide experimental evidence for understanding the forming mechanism of glass microlenses and microlens arrays in the contactless hot embossing process. The effects of process parameters, diameter and position of the micro-holes, hole diameter, and pitch of the micro-hole array mold on the filling deformation of glass in contactless hot embossing were comprehensively investigated. It is found that placing the micro-hole farther away from the mold center renders decrease in both filling height and tip curvature but increase in the eccentricity of the embossed glass microlens. As a result, the formed glass microlens array shows a nonuniform distribution of filling height and tip curvature. Furthermore, reducing the pitch of micro-hole array mold can significantly improve the uniformity of formed microlens array. Based on these experimental results, the forming mechanism of microlenses and microlens arrays in contactless hot embossing process is summarized. Finally, a glass microlens array with decent uniformity in the center area was hot embossed by using a SiC micro-hole array mold.

To effectively manage turbine blade weight and blade deflection under severe weather conditions, longer and stiffer blades are required, fiber glass producers have devoted significant efforts to developing and commercializing high-modulus (HM) glass fiber products of the first generation. The current focuses aim at the commercialization of the second generation and the development of the third-generation products. This article briefly reviews four key areas: (a) the benefit of longer blades on wind energy generation, (b) characteristics of HM glass fibers of various generations, (c) fundamental science and understanding behind HM glass fiber development, and (d) finally statistically based composition (C)–property (P) and structure (S)–property (P) modeling approaches in new glass design.