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The purpose of this paper is to study the mechanical response of polyurea, soda-lime glass (glass, for short), polyurea/glass/polyurea and glass/polyurea/glass sandwich structures under dynamic-loading conditions involving propagation of planar longitudinal shockwaves.

The problem of shockwave generation, propagation and interaction with material boundaries is investigated using non-equilibrium molecular dynamics. The results obtained are used to construct basic shock Hugoniot relationships associated with the propagation of shockwaves through a homogeneous material (polyurea or glass, in the present case). The fidelity of these relations is established by comparing them with their experimental counterparts, and the observed differences are rationalized in terms of the microstructural changes experienced by the shockwave-swept material. The relationships are subsequently used to predict the outcome of the interactions of shockwaves with polyurea/glass or glass/polyurea material boundaries. Molecular-level simulations are next used to directly analyze the same shockwave/material-boundary interactions.

The molecular-level simulations suggested, and the subsequent detailed microstructural analyses confirmed, the formation of topologically altered interfacial regions, i.e. polyurea/glass and glass/polyurea interphases.

To the authors’ knowledge, the present work is a first attempt to analyze, using molecular-level simulation methods, the interaction of shockwaves with material boundaries.

Glass material is largely used for load-bearing components in buildings. For this reason, standardized calculation methods can be used in support of safe structural design in common loading and boundary conditions. Differing from earlier literature efforts, the present study elaborates on the load-bearing capacity, failure time and fire endurance of ordinary glass elements under fire exposure and sustained mechanical loads, with evidence of major trends in terms of loading condition and cross-sectional layout. Traditional verification approaches for glass in cold conditions (i.e. stress peak check) and fire endurance of load-bearing members (i.e. deflection and deflection rate limits) are assessed based on parametric numerical simulations.

The mechanical performance of structural glass elements in fire still represents an open challenge for design and vulnerability assessment. Often, special fire-resisting glass solutions are used for limited practical applications only, and ordinary soda-lime silica glass prevails in design applications for load-bearing members. Moreover, conventional recommendations and testing protocols in use for load-bearing members composed of traditional constructional materials are not already addressed for glass members. This paper elaborates on the fire endurance and failure detection methods for structural glass beams that are subjected to standard ISO time–temperature for fire exposure and in-plane bending mechanical loads. Fire endurance assessment methods are discussed with the support of Finite Element (FE) numerical analyses.

Based on extended parametric FE analyses, multiple loading, geometrical and thermo-mechanical configurations are taken into account for the analysis of simple glass elements under in-plane bending setup and fire exposure. The comparative results show that – in most of cases – thermal effects due to fire exposure have major effects on the actual load-bearing capacity of these members. Moreover, the conventional stress peak verification approach needs specific elaborations, compared to traditional calculations carried out in cold conditions.

The presented numerical results confirm that the fire endurance analysis of ordinary structural glass elements is a rather complex issue, due to combination of multiple aspects and influencing parameters. Besides, FE simulations can provide useful support for a local and global analysis of major degradation and damage phenomena, and thus support the definition of simple and realistic verification procedures for fire exposed glass members.

The study aims to carry out the production of a bulk heterojunction organic solar cell in a laboratory scale using a blend of poly (3-hexylthiopene) (P3HT) and [6, 6]-phenyl (C61) butyric acid methyl ether (PCBM).

Four inverted geometry organic solar cells were prepared based on 1:1 ratio of P3HT to PCBM and subjected to post annealing at different temperatures of 32, 120, 130 and 140°C. Solar cells were fabricated with structure glass/ITO/P3HT:PCBM/PEDOT:PSS/Au and characterized using Keithley 2400 series sourcemeter and a multimeter interfaced to a computer system with a LabVIEW software, which showed both dark and illumination current–voltage characteristic curves. Four reference cells were also fabricated with structure soda lime glass/P3HT:PCBM and annealed at different temperatures of 32, 120, 130 and 140°C.

The third organic solar cell prepared, Sample CITO, had the best performance with power conversion efficiency (PCE) of 2.0281 per cent, fill factor (FF) of 0.392, short circuit current of −0.0133 A and open circuit voltage of 0.389 V. Annealing of active layer was found to improve cell morphology, FF and PCE. Annealing of the active layer at 140°C resulted in a decrease of the PCE to 2.01 per cent.

These findings are in good agreement with previous investigation in literature which reported that best annealing temperature for a 1:1 ratio blend of active material is 130°C. Ultraviolet–visible spectra on reference cells showed that sample CITO had wider absorption spectra with peak absorbance at a wavelength of 508 nm.

This research is purely original.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

SUMMARY The main overall problems associated with transparencies for manned supersonic and hypersonic aircraft are considered. Civil and military concepts are compared in relation to aircraft performance requirements and the reasons for the continuing need for optical transparencies are enumerated. Aircraft performance requirements and typical flight plans show the necessity for designing the transparencies to withstand a considerable range of environmental conditions in addition to the aerodynamic dictates in relation to size, position and shape. These conditions are listed and design feature considerations are discussed in some detail with particular accent on the thermal problems. Reference is made to certain organic and inorganic materials for the basic glazings and the problems associated with the ‘marrying’ of these materials with retaining frame members are discussed. Detail proposals are made for typical windscreen and canopy assemblies. Brief reference is made to the poor reliability shown by many transparencies in present‐day modern aircraft which indicates the need for revision of certain existing test requirements. The proposed new requirements will result in the development of new testing techniques although test factors might well be reduced. The paper concludes with a statement on the importance which is being given to the subject matter by the various bodies in the U.K. and the emphasis which should be placed on the need for the continuation of research and development work in this field.

The aim of the work described was to investigate the effect of the glass microstructure, changed during chemical and thermal treatments, upon the micro-hardness and microcracking of the exchanged specimens. Commercially available soda-lime silicate glass samples have been doped with copper. After ion-exchange, some of the specimens were annealed in the hydrogen atmosphere. Transmission electron microscopy, the XRD and electron diffraction techniques were used to characterize the microstructure of the glass-composites. Additionally, the linear thermal expansion coefficient was measured. The detected strengthening effects have been explained by supposing the formation of copper oxide and some mixed sodium-copper silicates. The induced decrease of the thermal expansion coefficient of this layer results in the formation of strong compressive stresses.

The factors which should be considered when contemplating windshield design are outlined, and various levels of high performance vehicles are defined. The relationship between environment and design criteria is discussed and the author introduces some of the unique glasses in current use.

Glass is a brittle material produced from silica, which has fine material properties, Owing to its sophisticated material properties, glass has found wide application in various high-technological fields such as aviation, aerospace, communication, optics, biomedical and electronics. However, glass is known as difficult to machine material because of its tendency to brittle fracture during machining. This paper aims to investigate the effects of cutting parameters on surface quality and machining time during micro-milling of brittle glass components.

A comprehensive genetic algorithm-based optimization strategy is used for selection of process parameters such as cutting speed, feed rate and depth of cut. Effectiveness of the proposed strategy is validated by conducting micro-milling cutting experiments on soda-lime glass material.

Results showed that the generated surface quality drastically decrease with increase in the amount of removed material. Lower depth of cut and feed rate result in less amount of cracks formed on machined surface. Also, it is observed that the increase in cutting speed results in better surface quality. Having desired surface quality in shorter machining time directly reduces energy consumed during manufacturing, which is reducing environmental impact of glass parts.

The novelty of this research work lies in simultaneously considering the effects of cutting speed, feed rate, depth of cut on surface quality and machining time for micro-milling operation of brittle glass material. The model is able to find optimum process parameters for high surface quality and minimum machining time.

The construction of windscreen panels for modern aircraft is described and the role of each component in meeting the requirements for pressure strength, bird resistance and optical performance is discussed. The influence of the physical properties of the windscreen components on the performance of complete laminated windscreens is discussed and the limitations imposed by these properties indicated. Silicone inter‐layers are beginning to replace polyvinyl butyral inter‐layers in high‐speed aircraft laminated transparencies when the temperatures reached are above the working limit of the conventional interlayers. New types of glass capable of withstanding prolonged exposure to higher temperatures than soda lime silica glass without loss of toughening stress, and also capable of withstanding more severe thermal shock without fracture, have been developed.