Glass Material

8 Key excerpts on "Glass Material"

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  Modern Materials

  Advances in Development and Applications

  • Bruce W. Gonser(Author)
  • 2013(Publication Date)
  • Academic Press

    (Publisher)

  ENGINEERING GLASS Errol B. Shand Technical Consultant on Glass and Ceramics, Corning, New York Page I. Nature and Chemical Composition 248 A. Definition 248 B. The Vitreous State 249 C. Chemical Composition 251 D. Devitrification 253 II. Manufacture 255 A. Raw Materials and Melting 255 B. Forming 256 C. Secondary Processes 257 III. Properties 259 A. Viscosity 260 B. Specific Heat and Thermal Conductivity 262 C. Emissivity 262 D. Thermal Expansion 262 E. Mechanical Properties 265 F. Optical Properties 271 G. Electrical Properties 273 H. Chemical Properties 276 IV. Engineering of Glass 277 Structural Design of Brittle Materials 278 V. Glass in Buildings 289 A. Glass Products 289 B. Large Panes 290 VI. Vehicle Glazing 296 A. Land Vehicles 296 B. Aircraft 297 C. Spacecraft 298 D. Deep Submergence Craft 300 VII. Industrial Uses 303 A. Piping 304 B. Other Equipment 306 C. Heating Panels 306 D. Fluid Amplifiers 306 E. Glass Lubricants 307 VIII. Lamp and Electronic Industries 307 A. Lamps 307 B. Electron Tubes 310 C. Electronic Circuit Components 311 D. Microwire 312 247 248 ERROL B. SHAND E. Radomes 312 F. Vacuum Switches 313 IX. Glass for Science 313 A. Linear Particle Accelerators 313 B. Radiation Absorbers 314 C. Bubble Chamber Windows 314 X. Summary 315 References 316 I. Nature and Chemical Composition Glass has characteristics that, collectively, are not found in other engineering materials. 1 It is transparent, hard, and brittle at ordinary temperatures, but becomes increasingly more fluid with rising tempera-ture. It is corrosion-resistant and is a good electrical insulator. Because of these unusual characteristics the principal applications of glass are found in somewhat specialized fields, and the technical approach to engineering problems involved is not always the same as for other materials. A. DEFINITION Glass is a ceramic material; that is, it is made from inorganic materials at high temperatures.

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  Modeling Fracture Behavior in Precision Glass Molding

  • Gang Liu(Author)
  • 2018(Publication Date)
  • Apprimus Wissenschaftsverlag

    (Publisher)

  2 State of the Art - 9 - 2 State of the Art Stand der Technik 2.1 Glass Material and properties Glasmaterial und Eigenschaften “Glass is a hard, brittle substance, typically transparent or translucent, made by fusing sand with soda and lime and cooling rapidly. It is used to make windows, drinking containers, and other articles.”- Oxford English Dictionary [SIMP89]. Glass is a common material which appears everywhere in our daily lives. As a typical amorphous material, glass exhibits typical “glass transition” behavior. The glass transitions can be observed from the volume versus temperature diagrams, such as those shown in Figure 2.1. The glass liq- uefies above the melting temperature (T m ). During the cooling process the atomic structure of the melt will gradually change. During the gradual cooling process the crystalline state of the melt can be obtained, with the formation of long-range, periodic atomic arrangements below the melting temperature. During the rapid cooling process the melt becomes a super-cooled liquid without crystallisation. As the super-cooled liquid continues to be cooled, the increase in viscosity speed is faster than the rearrangement speed of atoms to the equilibrium liquid structure until it reaches the solid state [SHEL05]. Therefore, the volume change of the super-cooled liquid (red solid line) deviates from the equilibrium line (red dashed line). This phenomenon is called ‘glass transition’. The temperature of the intersection point of the liquid and solid equilibrium line is called the ‘glass transition temperature’ (Tg). Figure 2.1: Volume changes during the glass formation process Volumenänderung während des Glasformungsprozess Humans first produced glass thousands of years ago (5000 BC) in the region of Mesopotamia [PLIN1847]. The glass was produced on the shore by adding the combination of sea salt (NaCl) and bones (CaO) into the embers of fire built on the sands (SiO 2 ) at the edge of a saltwater sea [SHEL05].

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  Modern Methods for Analysing Archaeological and Historical Glass

  • Koen H. A. Janssens(Author)
  • 2013(Publication Date)
  • Wiley

    (Publisher)

  1.1 What is Glass? An Introduction to the Physics and Chemistry of Silicate Glasses

  José-María Fernández-Navarro1 and María-Ángeles Villegas2

  1 Instituto de Óptica Daza de Valdés CFMAC, CSIC, Madrid, Spain

  2 Instituto de Historia, CCHS, CSIC, Madrid, Spain

  1.1.1 Introduction

  The purpose of this introductory chapter is to present the basic concepts of the glassy state as well as the main properties of glasses that are different from those of other materials. There are two questions of theoretical interest to which many authors have paid special attention. These questions are the following: on the one hand, the establishment of structural models describing the behaviour of different kind of glasses and, on the other hand, the knowledge of the conditions that a substance must meet in order to obtain a glassy state (i.e. geometrical-structural factors, thermodynamics, kinetics, chemical bonding, etc., on which the ability to form a stable glass depends).

  In this chapter only the main properties of glasses will be considered: viscosity and thermal expansion coefficient, affecting glasses during their heating and cooling, and the most important properties for their application and use, such as mechanical behaviour, optical transmission, reflectance and chemical durability.

  The concept and meaning of the word glass depends on the corresponding context. In colloquial language the word glass is used to name objects made in this material (goblets, ophthalmic lenses, table vessels, etc.). In the scientific and technical world, the word glass is used for a wide series of materials with very different chemical composition, having all the fundamental physical and chemical characteristics that define the glassy state.

  A material can be obtained in a glassy state through condensation from a gaseous phase, via cooling or polymerisation from a liquid phase or by disordering a solid phase. All of these pathways yield a non-crystalline structure. The most commonly used manner of obtaining a glass is the cooling of a liquid phase.

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  Glass

  Mechanics and Technology

  • Eric Le Bourhis(Author)
  • 2014(Publication Date)
  • Wiley-VCH

    (Publisher)

  Table 2.4 lists the main properties of glass according to various applications.

  Table 2.4

  Attractive glass properties for different applications.

  Transparency	Strength	Rheology	Chemical inertness
  Glazing	++	++	++	++
  Containers	+	++	++	+++
  Optical glass	+++	+	+
  Glass wool	++	++	++
  Fibres for reinforcement	++	++

  Transparency is obviously of utmost importance for glazing and optical glasses. This performance combined with strength, rheology and cost make glass very competitive as compared to polymers. In fact, rheology is a very important issue as regards the process. Glass even though not showing exceptional performances in all fields presents a combination of desired properties that makes it very attractive.

  Let us consider its transparency according to its cost (or price that takes into account the cost of raw materials, process, marketing and labour; see also Section 1.2.1), as shown in Figure 2.8 . In this figure, transparency is plotted as a function of price per volume from the materials database elaborated by Ashby's team (CES 4, Granta Design; Ashby, 2001). The optical performance is separated into four categories (i.e. opaque, translucent, transparent and optical quality). When considering transparency, the glassmaker is interested in the two last categories. Only dedicated optical devices require optical quality (i.e. extremely low optical loss). From the transparency–price chart, we already observe that glass is a very good compromise, since only polymers compete. Glass is generally preferred because of its strength, UV protection (in containers), chemical protection, chemical inertness (allowing for conservation of foods and liquid, a property that may remain at elevated temperatures) and tailored optical properties. Developments of glazing encompass tailoring optical properties with transparency at visible wavelength while being opaque to infrared and ultraviolet light (Lehmann, 2005; see also Chapter 4

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  Forensic Examination of Glass and Paint

  Analysis and Interpretation

  • Brian Caddy(Author)
  • 2001(Publication Date)
  • CRC Press

    (Publisher)

  2The composition and manufacture of glass and its domestic and industrial applications

  GEOFFREY J. COPLEY

  2.1 Introduction

  The glass industry is divided into broad sectors for the manufacture of containers (bottles and jars), flat glass (for architecture and transport glazing), glass fibre (for reinforcement and insulation), domestic glass (kitchen and tableware) and technical glasses (for a host of scientific and industrial uses). Manufacturing processes differ from sector to sector [1 , 2 ]. Technical and commercial developments in glass manufacture over the past, say, forty years have yielded new products, and methods of manufacture have changed dramatically in terms of speed of production, the quality of glass produced and the number of peripheral processes for treating glass. There are many different glass compositions but they fall into a limited number of types which simplifies classification [3 ]. A composition is developed to meet the requirements of the manufacturing process, the properties required in the use of the end product and the economics of production. Manufacturers’ catalogues show a wide range of products, with compositions which vary from product to product. In the large tonnage sectors (container, flat and domestic) compositions tend to be similar within each sector but there are differences of detail. Glass is manufactured in most technically advanced countries and there is a good deal of international trade. Since glass is a highly durable material, products can remain in use for long periods of time, with church windows providing an extreme example. Samples of glass arising from a particular site or event may therefore possess an easily determined composition be it ancient or modern, domestic or foreign.

  2.2 Definition of a glass

  Glass is defined as a product of fusion which has cooled to a rigid state without crystallisation. Glass is therefore, by definition, amorphous or non-crystalline. Glasses are essentially supercooled liquids and they possess a unique combination of properties: transparency with or without colour, durability, electrical and thermal resistance, a range of thermal expansions, with hardness, rigidity and stability. Glasses are made by melting together, and chemical reactions between, inorganic materials, many of them naturally occurring oxide minerals, of which the principal one is silica sand. Commercial glasses are therefore silicates. Depending upon the combination of properties needed in the end product, other additives are selected to optimise manufacture and performance.

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  Applied Optics and Optical Engineering V7

  • Robert Shannon(Author)
  • 2012(Publication Date)
  • Academic Press

    (Publisher)

  APPLIED OPTICS AND OPTICAL ENGINEERING, VOL. VII CHAPTER 2 Optical Materials—Refractive CHARLES J. PARKER Corning Glass Works, Corning, New York Introduction Optical Glass A. Description and Terminology B. Optical Properties C. Chemical Properties D. Physical Properties Vitreous Silica Glass A. Terminology B. Properties Optical Crystals Plastic Optical Materials Optical Materials for the Infrared A. Glasses B. Crystalline Materials C. Metallic Materials References 47 48 48 49 59 62 65 65 66 68 70 71 72 74 75 76 I. INTRODUCTION Refractive optical materials include broad classes of solids with closely specified optical properties that are useful for control of light in the ultra-violet, visible, and infrared spectral regions. The prime optical properties are refractive index and transmittance (i.e., absorption) and the wavelength dependence of these properties through the region of interest. In the visible region, where most optical materials are transparent, selection is made primarily according to index characteristics. Outside the visible, transparency is usually the critical property and the user fits his application to the index available. There is a variety of further properties, optical and otherwise, whose order of importance and specification depend strongly on the end use. These include, for example, inclusion quality, index homogeneity, scattering, chem-ical reactivity, thermo-optic and stress-optic coefficients, hardness, density, and strength. This chapter does not discuss polarizing or optically active refractive materials, or materials designed for optical thin films. 47 Copyright © 1979 by Academic Press. Inc. All rights of reproduction in any form reserved. ISBN 0-12-408607-1 48 CHARLES J. PARKER II. OPTICAL GLASS A. DESCRIPTION AND TERMINOLOGY Although it is one of the oldest optical materials, glass still offers the widest range of optical properties, and is the primary type of material used in the visible and near-visible region.

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  Metallic Glasses

  • Dragica Mini?, Milica Vasi?, Dragica Minić, Milica Vasić, Dragica Minić, Milica Vasić(Authors)
  • 2020(Publication Date)
  • IntechOpen

    (Publisher)

  Chapter 2 Metallic Glasses: A Revolution in Material Science Swadhin Kumar Patel, Biswajit Kumar Swain, Ajit Behera and Soumya Sanjeeb Mohapatra Abstract Metallic glasses represent one kind of advanced material, very popular in recent decades. These materials are very adaptable like plastics for their manufacturability in very complex shapes. TPF (Thermoplastic forming) based processes seem very good method to process them. These materials can compete with plastics but have metallic properties. They behave as magnetic materials with less hysteresis loss and less eddy current loss making them suitable for transformer and MEMS (Micro-Electromechanical System) applications. These materials exhibit good corrosion resistance, hardness and toughness. Based on the property and application, metallic glasses are good rivals to plastics, metals and ceramics. Chemical composition and kinetics of supercooling of these materials are the areas where young researchers can focus attention with a view to their improvement. Keywords: metallic glass, crystalline and amorphous structure, supercooling, TPF-based processing 1. Introduction In our day-to-day life, we use several types of products made from different materials. Based on the area of application, the desired properties of equipment for their production and processing can vary. According to this, material selection takes place in the way to supply the best possible outcomes compared to others. In recent decades, aluminum, steel and plastics have been the most commonly used materials. The aluminum is considered as the best choice for automobile and structural object for its low density and high specific strength, whereas, due to good strength and cost-effectiveness, steel is the most preferred material for structural applications like construction, railway industry etc. Likewise, plastics are used for various home and kitchen appliances and also for the interior design of buildings, vehicles etc.

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  Sustainability of Construction Materials

  • Jamal Khatib(Author)
  • 2016(Publication Date)
  • Woodhead Publishing

    (Publisher)

  The recent architectural and technological developments in the use of glass in building envelopes pose the challenge for structural engineers to design large areas of glass panels, roofs, floors, staircases and partitions. All these glass members will have a structural role compared to small glass panes used in traditional four-edge supported windows that engineers have been familiar with for centuries. Since glass is a brittle material, its structural behaviour is significantly different from that of more familiar materials such as steel and reinforced concrete. The structural designs of glass must take into account the fundamental material behaviour.

  5.9.1 Mechanical properties of glass

  Glass is a perfectly linear-elastic and isotopic material. The typical values of Young's modulus (E ), shear modulus (G ), Poisson's ratio (υ ) and density (ρ ) of glass are given in Table 5.3 .

  Table 5.3

  Basic mechanical properties of glass (BS EN 16612, 2013 )

  Mechanical property	Value
  Young's modulus, E	70 GPa
  Shear modulus, G	28.7 GPa
  Poisson's ratio, υ	0.22
  Density, ρ	2500 kg m− 3

  5.9.2 Strength of glass

  Since glass is a brittle material, its tensile strength depends on the inevitably present surface flaws. The geometry and the distribution of surface flaws are unknowable, and therefore the prediction of the strength of glass is challenging. The analysis of molecular forces indicates the tensile strength of glass is as high as 32 GPa (Haldimann et al., 2008 ), but since the surface flaws cause fracture, the actual tensile strength of float glass is in the range of 20–45 MPa (IStructE, 2014

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