Forming or fiberizing is achieved by pulling fibers through tiny orifices in a precious metal bushing. Laboratory bushings can have as few as one hole, whereas high-throughput production bushings typically have 1000 or greater. The image shows a glass fiber bushing (left) and close-up image of bushing tips (right). From Glass Fiber-Reinforced Composites: From Formulation to Application. Credit: IJAGS; Wiley.
New papers that have been accepted for publication in the International Journal of Applied Glass Science are posted to “Early View” on the Wiley website and can be read even before the issue is printed. Below are summaries of selected papers currently available via Early View.
All members of The American Ceramic Society receive free online access to the journal. To access any of the ACerS journals, or to become a member, visit www.ceramics.org.
The Fracture of Glass: Past, Present and Future
Stephen Freiman
Freiman summarizes brittle fracture in silicate glasses, including current knowledge, current studies and what remains unknown. He provides an annotated bibliography of significant publications and highlights several issues, including susceptibility of silicate glasses to environmentally enhanced crack growth, quantitative nature of markings left on fracture surface by a growing crack, issue of crack arrest at low stresses and atomistic modeling of the fracture process.
Glass Fiber-Reinforced Composites: From Formulation to Application
Joy M. Stickel and Mala Nagarajan
Stickel and Nagarajan of Owens Corning Science and Technology review the many available forms of glass-fiber reinforcements and their mechanical, thermal and corrosion properties. They emphasize that utmost care and consistency must be exercised in the fiber-forming process and that selection of a high-performance glass formulation enables use of composites in highly demanding applications.
Strength of High-Performance Glass Reinforcement Fiber
Michelle L. Korwin-Edson, Douglas A. Hofmann and Peter B. McGinnis
Another team of Owens Corning Science and Technology researchers reviews glass-fiber strength—pristine versus usable—and the effects of temperature, humidity and composition on glass strength. The team reports recently collected data on the effect of temperature and relative humidity on a variety of Owens Corning glass products.
Synthesis and Structural Probing of Eu3+ Doped BaYF5 Nano-Crystals in Transparent Oxyfluoride Glass-Ceramics
Kaushik Biswas, Atul D. Sontakke and Kalyandurg Annapurna
This research team from India’s CSIR-Central Glass and Ceramic Research Institute has confirmed the precipitation of tetragonal Eu:BaYF5 nanocrystals in transparent oxyfluoride glass-ceramics by melt quenching and optimized ceramization. The team reports the coexistence of Eu2+ and Eu3+ ions in the glass and glass-ceramics from their emission and excitation spectra as well as observed luminescence properties.
Glass Surface Layer Density by Neutron Depth Profiling
Cory L. Trivelpiece, John J. Petrunis, Carlo G. Pantano and R. Gregory Downing
Researchers from The Pennsylvania State University and National Institute of Standards and Technology synthesized Li2O∙2SiO2 glass samples, polished them and subjected them to static leach tests for various periods of time. They report that neutron depth profiling can be used to determine the average density of gel layers formed because of leaching of the alkali-silicate glass.
Interaction of Embedded Tri-Isotropic Fuel Particles with Melt of Alkaline Borosilicate Glass
Nasir H. Hamodi, Tristan Lowe and Timothy J. Abram
Researchers from the University of Manchester and the (Manchester) Material Science Centre studied the chemical bonding and interface formation of an alkaline borosilicate glass with the silicon carbide coating layer on tri-isotropic fuel particles with emphasis on the analysis of the intermediate chemical phase at the SiC/glass interface as a function of material impurity and SiC thickness. They report valuable information regarding restriction parameters of immobilization of tri-isotropic particles in glass: interaction between the glass and SiC caused total destruction of a thin SiC layer; random partial interaction to a thick SiC layer; and formation of CO2 and CO bubbles to an inner pyrolitic carbon.
Cladding Glass Development for Semiconductor Core Optical Fibers
Stephanie Morris, Steve W. Martin, Thomas Hawkins, Paul Foy, Robert Rice and John Ballato
This research team from Clemson University and Iowa State University of Science and Technology developed more-optimum silicate and non-oxide glass compositions for unary (Si, Ge), binary (InSb,GaAs) and ternary (GaAlSb) semiconductor cores. The team had two design criteria: matching the thermal expansion coefficient between semiconductor core and glass cladding and matching the viscosity-temperature dependences such that the cladding glass draws into fiber at a temperature slightly above the melting point of the semiconductor. The team provides preliminary experimental results on silicon-core optical fiber.
Thermoplastic Forming of Bulk Metallic Glasses
Sébastien Gravier, Georges Kapelski, Michel Suéry and Jean-Jacques Blandin
Researchers from the Université de Grenoble produce bulk metallic glasses for structural applications using a thermoforming process. They also preferentially thermoform metallic glasses in their supercooled liquid region. They report, however, that high-temperature deformation mechanisms of metallic glasses are not completely understood and that they continue to conduct intensive investigation to identify elementary deformation mechanisms.