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Flexible glass with high bending strength is a remarkable component of flexible electronic displays. However, as a brittle material, its bending properties often do not meet requirements of application. To address this challenge, the application of chemical strengthening stands out as a viable approach to significantly bolster scratch resistance and bending strength in flexible glass. This study focuses on a conventional one‐step chemical strengthening method, employing molten potassium nitrate, to reinforce ultrathin aluminosilicate glass produced through the secondary down‐drawing thermoforming process. Effects of ion‐exchange temperature and time on mechanical properties of strengthened 110 µm flexible glass were investigated, and moreover, properties of strengthened ultrathin flexible glass with various thicknesses were compared. The results indicate that, after chemical strengthening at 380°C for 1 h, the compressive stress (CS) of 110 µm glass reaches 864.60 MPa, and the depth of layer is 15.86 µm, at which time the glass has the best bending performance and scratch resistance, and half of the faceplate spacing during glass breakage can be enhanced from 38.02 ± 2.7 to 8.40 ± 0.62 mm. For ultrathin flexible glass from 40 to 110 µm, after treatment at 380°C for 1 h, the CS of thick glass is higher than that of thin glass, and the enhancement of bending performance is better. [ABSTRACT FROM AUTHOR]

Microforce plates are indispensable tools for quantitatively evaluating the behavior of small objects such as tiny insects or microdroplets. The two main measurement principles for microforce plates are: the formation of strain gauges on the beam that supports the plate and the measurement of the deformation of the plate using an external displacement meter. The latter method is characterized by its ease of fabrication and durability as strain concentration is not required. To enhance the sensitivity of the latter type of force plates with a planar structure, thinner plates are generally desired. However, brittle material force plates that are both thin and large and can be fabricated easily have not yet been developed. In this study, a force plate consisting of a thin glass plate with a planar spiral spring structure and a laser displacement meter placed under the plate center is proposed. The plate deforms downward when a force is exerted vertically on its surface, resulting in the determination of the applied force using Hooke's law. The force plate structure is easily fabricated by laser processing combined with the microelectromechanical system (MEMS) process. The fabricated force plate has a radius and thickness of 10 mm and 25 µm, respectively, with four supporting spiral beams of sub-millimeter width. A fabricated force plate featuring a sub-N/m spring constant achieves a resolution of approximately 0.01 µN. [ABSTRACT FROM AUTHOR]

Glass is a material with a rich history and a bright future. Due to its outstanding properties and its versatility, it is a key material in many applications. In this paper, we present a variety of these applications in which glass is playing, and will continue to play, a significant role, including communication technologies, the semiconductor industry, advanced displays, mobile consumer electronics, healthcare, and automotive. Other critical considerations enabling continuous progress in glass science and engineering, such as improved modeling tools and characterization techniques, increased sustainability of the glass‐making process, and talent development, are also discussed. [ABSTRACT FROM AUTHOR]

Microforce plates are indispensable tools for quantitatively evaluating the behavior of small objects such as tiny insects or microdroplets. The two main measurement principles for microforce plates are: the formation of strain gauges on the beam that supports the plate and the measurement of the deformation of the plate using an external displacement meter. The latter method is characterized by its ease of fabrication and durability as strain concentration is not required. To enhance the sensitivity of the latter type of force plates with a planar structure, thinner plates are generally desired. However, brittle material force plates that are both thin and large and can be fabricated easily have not yet been developed. In this study, a force plate consisting of a thin glass plate with a planar spiral spring structure and a laser displacement meter placed under the plate center is proposed. The plate deforms downward when a force is exerted vertically on its surface, resulting in the determination of the applied force using Hooke’s law. The force plate structure is easily fabricated by laser processing combined with the microelectromechanical system (MEMS) process. The fabricated force plate has a radius and thickness of 10 mm and 25 µm, respectively, with four supporting spiral beams of sub-millimeter width. A fabricated force plate featuring a sub-N/m spring constant achieves a resolution of approximately 0.01 µN.

Owing to the rapidly growing popularity of portable products, there is an increasing demand for lightweight devices with thin displays. Glass substrates contribute substantially to the thickness and weight of display panels, and therefore, it is important to minimize their thickness. However, thin glass substrates are too fragile to be supported on their own and used directly. Thicker glass substrates are therefore used to fabricate display panels, and the substrate thickness is then reduced through etching and surface grinding. This approach is time-consuming, involves the use of highly hazardous chemicals, and produces acidic liquid waste. Thus, countries in which thin panels are produced have experienced severe environmental pollution problems related to their manufacture. In addition to the pollution produced, existing panel-thinning methods cannot satisfy the demand for increasingly thinner panels, and as a result, there is an urgent need for new panel-thinning technologies. This article proposes a novel green temporary bonding and separation method that allows thin glass substrates to be carried to directly produce thin panels. This method makes possible the rapid manufacture of thinner glass display panels for foldable and flexible displays. This method does not use any chemicals and does not produce any polluting waste and thereby contributes to environmental protection.

For an existing building from 19th century an architectural concept for revivalism and reorganization into a modern office building was made. For this purpose, a daylight system was implemented that roofs the inner courtyard and at the same time makes it the central place of representation and communication. In addition to the spatial function, the inner courtyard serves as a thermal buffer room and additional value can be achieved by using thin glass and its material properties. The free‐form geometry benefits from the increased stiffness due to the curved shape, which is regulated by the radii of curvature depending on the material thickness. The curvature has a direct influence on the reflection behaviour, which influences the light transport of natural light into the interior of the room and thus enables a reduction in electrical lighting for the office space. [ABSTRACT FROM AUTHOR]

All‐glass systems such as mobile glass partition walls and all‐glass doors set high requirements for transparency, lightness and durability. The interconnection between the panels is conventionally performed by eye‐catching fittings and clamping details. Hence, innovative glass‐plastic‐composite panels, consisting of a systematic combination of a polymer Polymethylmethacrylate (PMMA) interlayer core and cover layers of thin glass, are currently under development. The units show high‐performance load‐bearing behaviour and exhibit full transparency at low panel self‐weight. Additionally, the novel composite allows for the implementation of a direct connection with the supporting structure into the PMMA interlayer core. These novel construction types will allow for small as well as unobtrusive connection details, which lead to the desired maximum transparency of all‐glass systems. Different connection joints such as fastened and bonded types were developed and tested with a focus on applications in all‐glass systems for the building industry. In this paper, the development process, and experimental results for different connection joints with glass and stainless‐steel substrates, tested under tensile and shear loading, are presented and evaluated in detail. For bonded joints, three transparent structural adhesives are included in the experimental program: UV acrylate, 2‐C epoxy resin and 2‐C polyurethane. Furthermore, the investigations consider detachable fastened connections. The results from form the basis for further investigations and an advanced design of connection details for the edge of glass‐plastic‐composites. A short outlook on the upcoming design of an ultra‐lightweight segmented glass arch adopting novel glass‐plastic‐composite panels and associated connections for the demonstration of the development in all‐glass applications completes the paper. [ABSTRACT FROM AUTHOR]

Im Rahmen der Masterarbeit, die in Zusammenarbeit mit dem Josef Ressel Zentrum für Dünnglastechnologie für Anwendungen im Bauwesen entstand, wurde ein Bestandsobjekt aus dem 19. Jahrhundert revitalisiert und zu einem modernen Bürogebäude umfunktioniert. Dazu wurde ein Tageslichtleitsystem implementiert, das den Innenhof überdacht und gleichzeitig diesen zum zentralen Repräsentations‐ und Kommunikationsort macht. Neben der räumlichen Funktion dient der Innenhof als thermischer Pufferraum und darüber hinaus kann durch die Verwendung von Dünnglas und dessen Materialeigenschaften ein zusätzlicher Mehrwert erzielt werden. Die frei geformte Geometrie profitiert von der erhöhten Steifigkeit durch die gekrümmte Form, die abhängig von der Materialdicke durch die Krümmungsradien reglementiert ist. Die Krümmung übt einen direkten Einfluss auf das Reflexionsverhalten aus, das den Lichttransport von natürlichem Licht ins Rauminnere beeinflusst und somit eine Verminderung der elektrischen Beleuchtung für die Büroräume ermöglicht. N46 – daylight control made of thin glass. As part of the master's thesis, which was created in cooperation with the Josef Ressel Center for Thin Glass Technology for Structural Glass, an existing building from the 19th century was revitalized and converted into a modern office building. For this purpose, a daylight system was implemented that roofs the inner courtyard and at the same time makes it the central place of representation and communication. In addition to the spatial function, the inner courtyard serves as a thermal buffer room and additional value can be achieved by using thin glass and its material properties. The free‐form geometry benefits from the increased stiffness due to the curved shape, which is regulated by the radii of curvature depending on the material thickness. The curvature has a direct influence on the reflection behavior, which influences the light transport of natural light into the interior of the room and thus enables a reduction in electrical lighting for the office space. [ABSTRACT FROM AUTHOR]

Innovative security glazing made of thin glass and polycarbonate In current architecture, the building material glass also enables large‐sized glazing for the building envelope, which results due to the high transparency in an undisturbed optical exchange between inside and outside. However, by increasing demands, in particular with regard to security and thermal insulation, the nominal thickness and dead load of the glazing also increase by using laminated safety glass and triple glazing. Meanwhile, the continuous development in the manufacturing process also enables the practical construction application of thin glass with nominal thicknesses below 2 mm as an alternative. Thin glass possesses a low dead load, however, combined with a low cross‐sectional stiffness. In order to avoid unacceptable deformations under load, thin glass is laminated, for example with polycarbonate, to a composite panel. The thin glass‐polycarbonate composite panels developed in two research projects at the Institute of Structural Design at Universität Siegen are used as vertical glazing made from single composite panels and multi insulated composite panels. The laminate of two outer thin glass panes with at least one inner polycarbonate sheet fulfils the requirements for laminated safety glass and achieves the highest resistance class P8B against manual attack with a cross‐section, which is slighter than common glass laminates. As part of the further development towards triple glazing, for the first time, all layers are considered to prevent the manual attack. This reduces the nominal thickness and dead load of the security glazing with resistance against manual attack compared to conventional solutions while considering a low thermal transmittance for the current requirements for thermal insulation. [ABSTRACT FROM AUTHOR]

Thin glass composite elements with additively manufactured polymer core This paper describes the concept of a composite element consisting of outer thin glass facings and an inner additively manufactured polymer core structure. The focus of the research work is on the design of a sandwich element which, due to the materials and manufacturing processes used, allows completely new flexibility in the design process of a glass facade. Three possible structures for the stiffening core are being developed and examined for their suitability for use in the composite element. The production of the first prototypes shows both the architectural potential and the production‐related specialties. Furthermore, the mechanical behaviour of the structure is investigated based on the sandwich theory using a 4‐point bending test. Based on the results obtained, the mechanical potential of the composite element can be underlined. However, the challenges to be overcome for safe use in facades are also specified. [ABSTRACT FROM AUTHOR]

Der architektonische Wunsch nach optischer Transparenz in der Gebäudehülle führt zu einem hohen Anteil an Verglasungselementen. Dabei müssen auch im Bauwesen steigende Sicherheitsanforderungen in einer unsichereren Welt zusätzlich berücksichtigt werden und sind insbesondere bei großformatigen Verglasungen nicht zu vernachlässigen. Ein neuartiges Verbundsicherheitsglas aus Dünnglas und Polycarbonat bietet die Möglichkeit zur Reduzierung der Eigenlast bei gleichzeitigem Erreichen der höchsten Widerstandsklasse P8B gegen manuellen Angriff. Zwei äußere Dünnglastafeln und eine oder mehrere innenliegende Polycarbonattafeln, laminiert mit einer thermoplastischen Zwischenschicht, definieren eine Dünnglas‐Polycarbonat‐Verbundtafel. Analytische Berechnungsmethoden betrachten dabei das Tragverhalten für statische Lasten. Die Studie beschreibt den Einsatz von chemisch vorgespanntem sowie nicht vorgespanntem Dünnglas in Kombination mit Polycarbonat. Die mit dem Vierpunkt‐Biegeversuch ermittelten Verformungen der Verbundtafeln werden mit berechneten Ergebnissen aus der Sandwichtheorie verglichen. Research on thin glass‐polycarbonate composite panels as sandwich element. The architectural desire for optical transparency in the building envelope leads to a high percentage of glazing. However, increasing safety demands in an uncertain world have also to be taken into account in the building sector. Therefore, also large‐sized glazing cannot neglect actual security requirements. An innovative laminate made of thin glass and polycarbonate offers the possibility of reducing the dead load while simultaneously achieving the highest resistance class P8B against manual attack. Two outer thin glass panes and one or more inner polycarbonate sheet laminated by a thermoplastic interlayer define the thin glass‐polycarbonate composite panel. Analytical methods analyse the structural behaviour for static loads. This study focuses on the application of chemically pre‐stressed thin glass and annealed thin glass in combination with polycarbonate. The tested deformation of the composite panel with the four‐point bending test are compared with the analytical calculated results of the sandwich theory. [ABSTRACT FROM AUTHOR]

In this paper, sulfide glass electrolyte powder with a nominal composition of (Li2S)60(SiS2)28(P2S5)12 is hot pressed at a 330°C and 12 MPa into separator films using non‐woven fiberglass reinforcement. The reinforced separator films are 93% dense, bendable, and have an ionic conductivity of 0.7 mS/cm at room temperature. When integrated into hybrid Li‐S coin cells with liquid electrolyte, these reinforced glass separators blocked the parasitic polysulfide shuttle sufficiently to enable reversible cycling without LiNO3 co‐salt. Furthermore, the scalability of the reinforced glass separator technology is demonstrated by assembling and testing a hybrid single‐layer pouch cell. [ABSTRACT FROM AUTHOR]

This paper investigates the stiffness and the durability of a composite panel that consists of thin glass as outer layers and a 3D printed core element from recycled PET. Thin alumino-silicate glass, mostly used for displays in computers, tablets and smartphones, is known for its flexibility, durability and high bending strength. However, for building applications, the high flexibility of thin glass may cause serviceability issues. Therefore, to stiffen thin glass, a composite concept of thin glass with a 3D printed core is developed. The core element of this panel consists of 3D printed recycled PET. The use of recycled PET has been taken into account, due to the increase of plastic waste for the next 30 years. A combination of both materials allows for a much stiffer composite panel and reduction in weight of 71,9 % compared to a normal double glazed window panel. This paper presents an overview of the durability of the composite panel. The durability aspects for this exploratory study are UV radiation, elevated temperature and fire. The UV radiation tests showed that the applied acrylic adhesive ensures for a good adhesion, which allows reaching high load bearing capacity. Also, these tests showed that recycled PET changes into a yellowish color and becomes more brittle. The temperature tests showed that at an elevated temperature of 80 ⁰C, recycled PET loses its stiffness and strength and cannot sufficiently take up forces when loaded. The fire experiments showed that the recycled PET core melted fully during the fire exposition.

Innovative glazing, which combines polycarbonate and thin glass to composite panels, ensures a slighter alternative to glass laminates with a high resistance against manual attack. Due to experimental studies, these thin glass-polycarbonate composite panels are classified as laminated safety glass and security glazing. The study describes analytical models to analyse their structural behaviour for static short time loads. In accordance to the geometrical boundary conditions of the four-point bending test, the composite panel can be described by the beam theory. A multi-layered system is calculated with the sandwich beam theory with a bending and shear deformation. Additionally, an extended approximate solution based on Wölfel is compared to the classical theory of sandwich elements as well as with experimental results.

Thin glass offers a promising prospect for lightweight façades with reduced use of raw materials, also opening up entirely new perspectives for architectural expression with its excellent optical quality as well as its high flexibility. The realisation of projects featuring thin glass as a structural element is so far limited due to several challenges led by structural issues mainly induced by the product's low stiffness. This paper attempts to bypass this issue by exploring the possibilities of the structural application of thin glass as a membrane element using examples of all-glass projects from the past as well as researches conducted in the present. The use of thin glass as a compressive member is impractical since the risk of buckling poses a greater threat than stress exceedance. As an alternative, its application as a tensile member is proposed, supported by examples from academic and industrial researches. In this context, a new type of glass support is introduced, enabling a moment-free load transfer into the glass.

Material testings of 3‐D printed cores for thin glass panels This paper describes the use of thin glass in a new concept for glass and facade construction. First of all, the basic properties of thin glass are presented and consequences for its use in building construction are identified. Then, the concept of using thin glass facade panels with 3‐D printed, adhesively bonded and stiffening polymer cores is presented. Small‐scale prototypes and design studies were performed in a series of master theses at the TU Delft. The insights gained from these studies confirmed the potential of thin glass in building construction. Current investigations at the Institute of Building Construction at TU Dresden include the continued and further development of this work. First results for 3‐D printed polymer cores with regard to their material and printing properties as well as the requirements are presented. Findings on reproducible printing quality and form finding supplement the designs in a clear manner. From the here presented studies, it is concluded that thin glass panels with adhesively bonded 3‐D printed cores are a feasible and promising concept for the construction of lightweight façade panels. [ABSTRACT FROM AUTHOR]

Fracture mechanics are utilized to successfully predict the allowable bend radii achieved through experimentation for ion‐exchanged glass having thicknesses of 25 to 125 microns. The origin of the non‐monotonic relationship between puncture resistance and glass thickness is also described. [ABSTRACT FROM AUTHOR]

Thin glass in façades: adhesive joints for thin glass composite panels with 3‐D printed polymer cores Thin glass is typically applied for displays on devices. Also, it enables new applications in architecture for example in glass façades. Due to its high strength and small thickness (0.1–2 mm) thin glass is very flexible, lightweight and easily bendable. However, thin glass cannot simply replace conventional façade glazing. To avoid too high deformations of the glazing as a result of the high flexibility, it has to be stiffened. An appropriate solution is the use of sandwich panels consisting of two thin glass panes with an inner polymer core. To achieve lightweight façade elements, 3‐D printed polymer structures are used instead of a solid core. The present study is dedicated to find a suitable adhesive to bond the polymer core to the thin glass. The mechanical and thermomechanical performances of different combinations of typical 3‐D printed polymers and transparent adhesives are evaluated. In addition, the influences of temperature and UV aging that occur in the area of the façades are investigated. [ABSTRACT FROM AUTHOR]

The manipulation of micro/nanoparticles has become increasingly important in biological and industrial fields. As a non-contact method for particle manipulation, acoustic focusing has been applied in sorting, enrichment and analysis of particles with microfluidic devices. Although the frequency and amplitude of acoustic waves and the dimensions of microchannels have been recognized as important parameters for acoustic focusing, the thickness of microfluidic devices has not been considered so far. Here, we report that thin glass microfluidic devices enhance acoustic focusing of micro/nanoparticles. It was found that the thickness of a microfluidic device strongly influences its ability to focus particles via acoustic radiation, because the energy propagation of acoustic waves is affected by the total mass of the device. Acoustic focusing of submicrometre polystyrene beads and Escherichia coli as well as enrichment of polystyrene beads were achieved in glass microfluidic devices as thin as 0.4 mm. Modifying the thickness of a microfluidic device can thus serve as a critical parameter for acoustic focusing when conventional parameters to achieve this effect are kept unchanged. Thus, our findings enable new approaches to the design of novel microfluidic devices.

Copyright of CE/Papers is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of CE/Papers is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glass, particularly in architectural design, expresses lightness and modernity. By rising glass surfaces of facades in buildings with high safety requirements, glass works as security glazing. Requirements of security glazing increase constantly. However, single glass panes do not fulfil the demands on these high technology products. Thereby, laminated glass or insulated glass are used to solve problems of the specifications in view of fire, heat, noise, sound and sun protection as well as safety, energy, design or media. The combination of different materials in a composite panel permits the optimisation in consideration of requested structural or mechanical properties. In this case, the lamination of brittle glass with ductile polycarbonate enables innovative composite panels, which extends the range of glazing with security relevant applications. Glass-polycarbonate composite panels are generally defined with two outer glass panes and one or more inner polycarbonate sheets, laminated with polymeric interlayers. The combination of these two materials demonstrates a more efficient alternative to common security glazing. Continuous developments in the field of thin glass result in more and more applications beyond the usage in smartphones or tablets. Large-sized thin glasses with a nominal thickness of 2 mm or less are for some time available and already used in science and technology. Applications of thin glass in the building sector demand to analyse the required material properties and to combine thin glass panes with additional layers due to its low geometrical stiffness. An option for applications of large-sized thin glass panes presents the lamination with polycarbonate. Thin glass substitute the two outer glass panes in glass-polycarbonate composite panels. Therefore, thin glass-polycarbonate composite panels are slighter than common security glazing. Several options for using thin glass in architecture and the lamination with polycarbonate are described as well as the required tests for using as laminated safety glass and security glass with resistance against manual attack.

Chemically strengthened thin glass (t < 2 mm) is a material that is stronger and due to its small thickness, more flexible than conventional window glass. As such, thin glass offers the possibility for lightweight and flexible glass façades that could change shape depending on external conditions. This paper explores this concept and presents an MSc study on the use of this material in adaptive façade panels. The behavior of thin glass in this context depends on different factors. The glass thickness and strength define its bending limits, while the desired geometry and movement affect its overall stiffness and visual outcome. In order to integrate these factors, different configurations of panels were analyzed in numerical models. These analyses showed the importance of understanding the desired movement and geometry in order to correctly define the supports and degrees of freedom of the panel, avoiding stress concentration (particularly on the edges) and allowing for an unobstructed movement of the panel. The development of these analyses resulted in the conception of a design example of an adaptive façade panel, taking into consideration the design requirements developed in the research. Finally, as a proof of concept, a mock-up was built simulating the behavior of the design example developed in this research. Although there is still the need for research to be developed so that thin glass can become a building material, this research showed that this is possible and that interesting results, regarding visual effect, ventilation and dead load reduction (in larger scale, an environmental impact reduction is also possible) can be achieved. Besides that, using thin glass in adaptive panels challenges the concept of glass as a static material, opening new possibilities for its use.

Façades play an important role in the control of energy flow and energy consumption in buildings as they represent the interface between the outdoor environment and the indoor occupied space. The option of regulating internal and external conditions acquires great relevance in new approaches to sustainable building solutions. Studies on climate adaptive façades show a very high potential for improved indoor environmental quality conditions and energy savings by moveable façades. A number of movable façades were realized in the past, but the use of thin glass with a thickness of 0.5 mm to 3 mm opens a brand-new field, that allows for playing with the geometry of the outer skin and the opportunity to make it adaptive by movement. Thin glass requires for curved surfaces in order to gain structural stiffness in static use. In kinetic façades the high flexibility of thin glass allows for new options for changes in size and position by bending of elements rather than implementing hinges in a system of foldable rigid panels. The geometry is based on the known theory of developable surfaces for keeping a low stress-level during movement. This allows for façades created from cold bent thin glass or curved laminated safety glasses produced by laminating of thin glass plies which provide better sealing, greater simplicity in construction and robustness and durability of moveable components which may be actuated autonomously. Some concepts based on the before mentioned theories were created to explain some principles and discuss their principles and applicability.

Thin glass is currently widespread in mobile devices and has great potential for applications in buildings. However, presently there is no standard method to determine the strength of thin glass for building applications and there is little experimental data available on its mechanical behaviour. Hence, this paper presents experimental and numerical investigations developed with two main goals: (i) to assess and (eventually) adapt existing test setups in order to determine the strength of thin glass; and (ii) to characterize thin glass using those tests, focusing on the ultimate strength of the material. The experimental programme, which was executed at TU Delft, comprised destructive tests on chemically tempered thin glass (thickness of 2 mm). Two destructive tests were assessed and tentatively improved: the in-plane four-point bending test, which involved many difficulties related with geometrical and mechanical instabilities; and the buckling test, which provided a lower bound for the material strength, as failure was triggered in the supports (due to stress concentrations). Based on the results obtained, a new tension test was proposed and numerically investigated; the results obtained revealed many advantages over the former tests in terms of quality/consistency of results and possibility of standardization.

Cold bent glass is nowadays of primary importance both for industrial and civil applications. In fact, thin glass with a maximum thickness of 1.5 mm is often part of a wide range of technological devices and architectural surfaces (e.g. touchscreens, displays, mirrors, optical instruments, claddings and building interiors). The manufacturing process of cold bent glass is generally considered faster and less demanding in terms of necessary equipment with respect to hot bending or casting techniques. On the contrary, both the design of the manufacturing procedure and of the products are still a challenge and they are mainly based on a trial and error approach. Generalized defects and imperfections are always present on the surface of the raw glass product, while another significant source of flaws is usually localized at the edges and it is associated with the specific cutting technique and edges processing. The aim of this work is to experimental investigate the influence of the edge processing on the failure strength of 1.5 mm glass plates by means of four point bending tests. Two edge conditions are taken into account: manual diamond cut and ground by hand-operated tool which introduces randomly diffused small-size flaws. Test results are then statistically assessed and compared with the stresses that arise during the cold bending process due to the imposed curvature. In the end, grinding somehow increases the level of damage as it increases the number of flaws. On the contrary, the improved uniformity of the damage leads to less scattered resistance values. These allows to achieve smaller curvature radii or, for a given design radius, it reduces accidental failures during the cold bending process.

Spatial load bearing structures in the building sector are usually built with the help of aligned steel‐glass elements in the form of a net. The installed glass elements are flat and have a large glass thickness, in order to achieve sufficient plate stiffness. This implied a less economical use of materials. Nowadays, due to new manufacturing techniques it is possible to use resource saving materials, e.g. thin‐walled laminated safety glass (ttotal ≤ 5.38 mm). For this purpose, the thin‐walled laminated safety glass consists of thin glasses (t < 3 mm) and interlayer materials. The thin‐walled laminated safety glass is cold bent onto shaping frame girder elements (uniaxial or double curved) at the installation site with subsequent continuous supports. In general, this leads to a spatial load bearing capacity of the single element under pressure and suction loads. The process of cold bending is easily feasible due to the lower resetting effect of the thin‐walled laminate. For this case, a state of cold bending is activated in the glazing. With additional loading perpendicular to their shell level a state of loading is generated. To this, the load‐bearing capacity depends on many parameters (time‐ and temperature‐dependent material behaviour, geometry and supporting conditions). The aim of curved single elements is to achieve maximum geometric stiffness more specifically maximum static resistance ERd. For this reason, the influencing parameters were mathematically, numerically and experimentally investigated and discussed plus transferred to a design method for two exemplary cold bent structures (uniaxial or double curved). [ABSTRACT FROM AUTHOR]

The use of thin glass in the field of electrical engineering for screens of mobile phones or laptops is well known and the necessary material requirements such the scratch resistance has been sufficiently researched. For applications in the building sector, however, the determination of the bending tensile strength of such thin glass necessary for structural design represents a new research topic. The test scenarios described in the standard series EN 1288 relevant for the determination of the bending tensile strength, such as the ring‐on‐ring test or the four‐point‐bending test, are not applicable for glass with a thickness of less than 3 mm. One reason is e.g. the high flexibility of the glass in case of four‐point‐bending tests. As a consequence, these test scenarios have to be adapted or new test scenarios have to be developed. The double‐ring bending tensile test was adapted in that the loading ring, e.g. was replaced by a pressure pad of soft elastomer. Thus, a constant stress distribution in the area under the pressure pad necessary for the determination of the probability of failure could be achieved. The four‐point‐bending test was replaced by test set‐ups in which the force is introduced in‐plane – parallel to the glass surface – as a membrane force in the glass and the glass is thereby deformed or bent until breakage analogous to a stability test. Another variant is bending with a constant bending radius. In this test set‐up, a circular arc is created by precise adjustment of the distance of the supported smaller straight edges and their rotation. Thus, the length of the edge, at which sets a constant bending moment can be increased. These alternative test scenarios were theoretically developed and analysed or partially experimentally investigated by means of test series. These experimental series serve to validate the theoretical development of suitable experimental scenarios and are intended to provide a first approach for a necessary adaptation of EN 1288. [ABSTRACT FROM AUTHOR]

Glass, particularly in architectural design, expresses lightness and modernity. By rising glass surfaces of facades in buildings with high safety requirements, glass works as security glazing. Requirements of security glazing increase constantly. However, single glass panes do not fulfil the demands on these high technology products. Thereby, laminated glass is used to solve problems of these specifications. The combination of different materials in a laminate permits the optimisation in consideration of desired structural or mechanical properties. In this case, the lamination of brittle glass with ductile polycarbonate enables innovative composite panels, which extend the range of glazing with security relevant applications. Glass‐polycarbonate composite panels are generally defined with two outer glass panes and one or more inner polycarbonate sheets, laminated with polymeric interlayers. The combination of these two materials demonstrates a more efficient alternative to common security glazing. Continuous developments in the field of thin glass result in more and more applications beyond the usage in smartphones or tablets. Large‐sized thin glasses with a nominal thickness of 2 mm or less are for some time available and already used in science or technology. Applications of thin glass in the building sector demand to analyse the required material properties and to combine thin glass panes with additional layers due to its low geometrical stiffness. An option for applications of large‐sized thin glass panes presents the lamination with polycarbonate. Thin glass panes substitute the two outer glass panes in glass‐polycarbonate composite panels. Therefore, thin glass‐polycarbonate composite panels are slighter than common laminated safety glass. Several options for using annealed thin glass and chemically strengthened thin glass in architecture and the lamination with polycarbonate are described as well as the required tests for using as laminated safety glazing and security glass with a resistance against manual attack. [ABSTRACT FROM AUTHOR]

Double-side or 3-D integration of high-precision and high-performance bandpass and lowpass filters that are interconnected with through-vias were designed and demonstrated on 100-micron thin glass substrates for ultra-miniaturized diplexer components. A novel process for achieving high precision with large-area fabrication was developed to achieve much improved tolerance in electrical performance. High-precision, high quality factor, and high component densities with thin-film layers on glass were used to realize innovative topologies on glass for high out-ofband rejection and low insertion loss. Low-loss 100-mm thick glass cores and multiple layers of 15-mm thin polymer films were used to build the filters on substrates. The demonstrated diplexers have dimensions of 2.332.83.2 mm. Aided by the dimensional stability of glass and process control with semiadditive patterning, the performance of the fabricated filters showed excellent correlation with the simulation. The impact of process-sensitivity analysis on diplexer performance was also analyzed. Finally, a unique and innovative process solution was demonstrated to control the process deviation and achieve good diplexer tolerance. The performance deviation was controlled by ~3.5X with the new process. [ABSTRACT FROM AUTHOR]

The femtosecond laser ablation process for cutting thin aluminoborosilicate glass sheets of thickness 100 μm was investigated with emphasis on effective cutting speed ( V eff ) and mechanical strength of diced samples. The process parameters including the laser fluence ( F ), overlap ratio ( r ) of the laser beam and polarization direction were varied at a fixed pulse repetition rate f  = 1 kHz to find the optimal process condition that maximizes V eff and edge strength. A three-point bending test was performed to evaluate the front-side and back-side bending (edge) strength of the laser-cut samples. V eff was proportional to F unless r exceeded a critical value, at which excessive energy began to be delivered at the same spot. The front-side edge strength was bigger than the back-side strength because of the back-side damages such as chipping. Good edge strength, as high as ∼280 MPa (front-side) and ∼230 MPa (back-side), was obtained at F  = 19 J/m 2 , r  = 0.99, with laser polarization vertical to the cutting path. [ABSTRACT FROM AUTHOR]

Glass with a thickness of 0.55 up to 2.0 mm can be defined as a thin glass or even as ultra-light. On the market there are several suppliers, which offer such thin glass. On the one hand there are e.g. Gorilla Glass produced by Corning Incorporated or Leoflex by AGC, which are pre-stress by chemical treatment and on the other hand there are soda lime silicate glass products, which are pre-stress by thermal or chemical treatment. Not only the design with thin glass causes a totally new kind of thinking, also possible test scenarios for determination of the ultimate bending strength are currently not distinctly regulated in standards. Some existing test set-ups described in standards e.g. EN 1288 (four-point bending test or large ring on ring test) cannot be used for the determination of the ultimate bending tensile strength of thin glass. Different test set-ups published in several papers show possibilities for alternative determination of ultimate bending strength. These different configurations were investigated and analyzed for their applicability for determination of bending strength of thin glass. This paper gives a summary of theoretical investigation and shows results of experimental testing.

Abstract: Laser processing of thin glass has proven problematic due to the inefficient coupling of optical energy into glass and difficulty achieving economical processing speed while maintaining cut quality. Laser glass processing is pertinent to touch screen display, microfluidic, microoptic and photovoltaic applications. The results of the laser scribing of 110μm thick alkali free glass with ultrashort polarised laser radiation are presented. A novel ex-situ characterisation procedure is reported which enables effective characterisation of the scribe depth, width, shape and the morphology of the laser material interaction zone. A study of glass cross sections scribed with laser polarisation oriented parallel to the plane of incidence (P polarised) showed damage regions extending away from the trench walls and correlated damage on the rear surface; these regions are indicative of damage caused by light transmission. The damage was significantly reduced by altering the polarisation from parallel to be perpendicular to the plane of incidence (S polarised) due to the increased reflectance from the trench walls. The processing speed was also impacted by the laser polarisation; it was found that S polarised light required less passes to fully ablate through the glass substrate. A processing window capturing the peak of the polarisation effect was identified. An optical model was developed to predict the effect of polarisation on the intensity distribution reaching the rear surface of the glass. S polarised light increases the reflectance resulting in a waveguiding effect which confines a larger amount of the light in the trench. Consequently we see an increased fluence incident on the central region of the trench. [Copyright &y& Elsevier]

ABSTRACT Optical losses are a major source for current and power reduction in solar modules. Hence, various improvements aiming at reducing these losses have been suggested. In this work, we have evaluated the effects of anti-reflective coating, front glass thickness, polyvinyl butyral ultraviolet+ encapsulant, and light harvesting strings on the module performance individually and in combination. The individual and combined contributions were quantified by spectrally resolved optical measurements on the module components and simulations as well as electrical measurements on 1-cell and 54-cell modules. Optical gains and their impact on short circuit current are discussed in relation to a maximum current obtained from the solar cells internal quantum efficiency. The results of the electrical characterization are in good agreement with the optical analysis substantiating our approach. They show that a combined, relative current enhancement of 5% can be obtained for an optimized module, which compares to an increase of 1% absolute efficiency. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]