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Glass
Kinds of Glass Terms modified by Glass Selected AbstractsROMAN WINDOW GLASS: A COMPARISON OF FINDINGS FROM THREE DIFFERENT ITALIAN SITESARCHAEOMETRY, Issue 2 2010R. ARLETTI Thirty-three samples of window glass and five glass lumps coming from three Italian archaeological sites,the Suasa excavations (Ancona, settled from the third century bc to the fifth to sixth centuries ad), the Roman town of Mevaniola (Forlì-Cesena, settled from the Imperial Age up to the fourth century ad) and Theodoric's Villa of Galeata (Forlì-Cesena, settled from the sixth century ad onwards),were analysed to track the changes in the chemical composition and manufacturing technology of window glass through the centuries. The aims of this study were: (1) to establish the origin of the raw materials; (2) to verify the chemical homogeneity among samples coming from different sites and/or produced using different techniques; and (3) to sort the samples into the compositional groups of ancient glass. The analysis of all the chemical variables allowed two groups to be distinguished: (a) finds from Mevaniola and Suasa; and (b) finds from Galeata. All the samples had a silica,soda,lime composition, but the analysis of minor elements,in particular, of Fe, Mn, and Ti,made it possible to split the samples into two groups, with the higher levels of these elements always found in the Galeata samples (HIMT glass). In conclusion, it can be asserted that the main differences between the samples are related to their chronology. [source] ARCHAEOMETRICAL INVESTIGATION OF SICILIAN EARLY BYZANTINE GLASS: CHEMICAL AND SPECTROSCOPIC DATA*ARCHAEOMETRY, Issue 1 2010R. ARLETTI A series of early Byzantine glasses, recovered in Ganzirri (Sicily, Italy), was analysed for major, minor and trace elements. All the analysed fragments were found to be natron-based silica,lime glass. Concerning minor and trace elements, the samples can be divided into two groups: glass with high Fe, Ti and Mn contents (HIMT glass) and glass with low levels of Fe, Ti and Mn. These results, strictly in agreement with literature data for glass of the Mediterranean region, can be interpreted as a consequence of the wide trade network established in this region and of the intense circulation of raw glass and artefacts from different Mediterranean areas. X-ray absorption spectroscopy studies at Fe and Mn K-edges, performed on HIMT glass, indicate that Fe is in the oxidized form while Mn is in the reduced form. [source] DEEPLY COLOURED AND BLACK GLASS IN THE NORTHERN PROVINCES OF THE ROMAN EMPIRE: DIFFERENCES AND SIMILARITIES IN CHEMICAL COMPOSITION BEFORE AND AFTER ad 150*ARCHAEOMETRY, Issue 5 2009V. VAN DER LINDEN In this work we attempt to elucidate the chronological and geographical origin of deeply coloured and black glass dating between 100 bc and ad 300 on the basis of their major and trace element compositions. Samples from the western and eastern parts of the Roman Empire were analysed. Analytical data were obtained by means of a scanning electron microscope , energy-dispersive system (SEM,EDS, 63 samples analysed) and laser ablation , inductively coupled plasma , mass spectrometry (LA,ICP,MS, 41 samples analysed). Among the glass fragments analysed, dark brown, dark purple and dark green hues could be distinguished. Only among the dark green fragments could a clear compositional distinction be observed between fragments dated to the periods before and after ad 150. In the early samples (first century bc to first century ad), iron, responsible for the green hue, was introduced by using impure sand containing relatively high amounts of Ti. In contrast, a Ti-poor source of iron was employed, containing Sb, Co and Pb in trace quantities, in order to obtain the dark green colour in the later glass samples. The analytical results obtained by combining SEM,EDS and LA,ICP,MS are therefore consistent with a differentiation of glassmaking recipes, detectable in glass composition, occurring in the period around ad 150. [source] THE ANALYSIS OF SECOND MILLENNIUM GLASS FROM EGYPT AND MESOPOTAMIA, PART 1: NEW WDS ANALYSES,ARCHAEOMETRY, Issue 4 2006A. J. SHORTLAND A recent analytical study by SEM,WDS was carried out on 226 glasses from the Late Bronze Age, analysing each of the glasses for a total of at least 22 elements, the largest such analytical study conducted on these glasses. The aim of the analysis was first to identify which elements were brought in with each of the raw materials and, second, to accurately characterize those raw materials. Since different glassmaking sites in Egypt and the Near East would probably use at least some local raw materials and these raw materials will vary slightly from site to site, this has potential for provenancing the glass. Analysis showed new patterns in the compositions of glass from the various sites and led to new conclusions about the supply of raw materials and personnel for the glass workshops. This forms the basis for further work by LA,ICPMS to be presented in part 2 of this paper. [source] THE COMPOSITION AND MANUFACTURE OF EARLY MEDIEVAL COLOURED WINDOW GLASS FROM SION (VALAIS, SWITZERLAND),A ROMAN GLASS-MAKING TRADITION OR INNOVATIVE CRAFTSMANSHIP?*ARCHAEOMETRY, Issue 2 2005S. WOLF Archaeological excavations between 1984 and 2001 at the early Christian cemetery church in Sion, Sous-le-Scex (Rhône Valley, Switzerland), brought to light more than 400 pieces of coloured window glass dating from the fifth or sixth centuries ad. The aims of this paper are threefold: first, to characterize the shape, colour and chemical composition of the glass; secondly, to understand whether the production of the coloured window panes followed traditional Roman glazing techniques or was of a more innovative nature; and, thirdly, to provide some indications as to the overall design of these early ornamental glass windows. Forty samples of coloured glass have been analysed by wavelength-dispersive X-ray fluorescence. The results of the chemical and the technological studies showed that most of the glass was produced using recycled glass, particularly as a colouring agent. Some of the glass was made of essentially unmodified glass of the Levantine I type. The results taken together seem to confirm that raw glass from this region was widely traded and used between the fourth and seventh centuries ad. The artisans at Sion were apparently still making use of the highly developed techniques of Roman glass production. The colour spectrum, manufacture and design of the windows, however, suggest that they represent early examples of ornamental coloured glass windows. [source] MORNING CLEANING: JEFF WALL AND THE LARGE GLASSART HISTORY, Issue 5 2009CHRISTINE CONLEY Jeff Wall's Morning Cleaning, Mies van der Rohe Foundation, Barcelona, 1999, is a cinematographic digital transparency picturing the German Pavilion designed by Mies for the 1929 International Exposition in Barcelona and reconstructed in the 1980s. The tableau involves the arrested action of a male cleaner, oblivious to the gaze of the spectator, as he washes the windows separating the interior from an outdoor pool, where the morning sun illuminates Georg Kolbe's sculpture Dawn. Contrary to Michael Fried's reading of Morning Cleaning as a renewal of the antitheatrical aims of High Modernist painting, this essay looks to Duchamp's Large Glass as the model for its structuring tensions. Morning Cleaning is considered as a Duchampian delay in relation to the politics of modernist glass architecture in Wall's Kammerspiel essay, and as a ,countermonument' to the reconstructed pavilion as fetish, emptied of social meaning and the traumatic history of modernity. [source] Wireless network analysis using per call measurement dataBELL LABS TECHNICAL JOURNAL, Issue 4 2007Michael J. Flanagan The advent of per call measurement data (PCMD) in Alcatel-Lucent network products has enabled an unprecedented view into code division multiple access (CDMA) network operation at the subscriber level. The timing information available in PCMD records allows for maximum-likelihood estimation of subscriber locations using experimental geo-location analysis software suite (GLASS) tools developed at Alcatel-Lucent. Spatial variations of traffic densities, lost call densities, and other phenomena can now be readily studied to better understand wireless network operation as experienced by subscribers. These types of tools can also incorporate financial and business details regarding subscribers to guide network operation and optimization activities more effectively. © 2007 Alcatel-Lucent. [source] Growth of lead bromide polycrystalline filmsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2004M. Giles Abstract Lead bromide polycrystalline films were grown by the physical vapor deposition method (PVD). Glass 1,x1, in size, uncoated, and coated with Indium Tin Oxide (ITO), was used as substrate and rear contact. The starting material was evaporated at temperatures from 395°C to 530°C under high vacuum atmosphere (6 x 10 -3 Pa) and during 8 days. The substrate temperature was prefixed from 190°C to 220°C. Film thickness yielded values from 40 to 90 ,m. Optical microscopy and scanning electron microscopy (SEM) were performed on the films. Grain size resulted to be from 1.0 to 3.5 ,m. SEM and X-ray diffraction indicate that films grow with a preferred orientation with the (0 0 l) planes parallel to the substrate. The Texture Coefficient (TC) related to the plane (0 0 6) was 7.3. Resistivity values in the order of 1012 ,cm were obtained for the oriented samples, but a strong polarization indicates severe charge transport problems in the films. Film properties were correlated with the growth temperature and with previous results for films of other halides. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The Surgical Looking Glass: A Readily Available Safeguard Against Eye Splash Injury/Contamination During Infiltration of Anesthesia for Cysts and Other "Porous" Lesions of the SkinDERMATOLOGIC SURGERY, Issue 4 2002Patrick R. Carrington MD Background. "Breaks" in barrier precautions are a definite abrogating influence on the effectiveness of "universal precautions." Dermatologists and dermatologic surgeons are exposed to significant infectious agents on a daily basis, especially due to the high number of minor surgical procedures performed. Backsplash, spray, and eye splash of bodily fluids during these procedures place the surgeon at a high risk of contamination/infection via the conjunctival membranes. The surgical looking glass is a simple utility based on inexpensive equipment already in place in the physician's office which protects the eyes and face during infiltrative anesthesia or incision of cysts and other lesions. Objective. To offer a simple and inexpensive utility to assist with protection from and reduction of contamination/infection of the ocular mucous membranes during surgical procedures. Methods. Utilizing one or two readily available microscope slides overlying the injection site during local infiltrative anesthesia, backsplash or spray can be contained. Results. This utility is effective in containment of backsplash or spray of anesthesia or bodily fluids during even minor surgical procedures. Conclusion. The surgical looking glass can enhance safety and promote "universal precautions" during even minor surgical procedures or infiltration of anesthesia into more porous areas or lesions for the practicing dermatologist or dermatologic surgeon. The pragmatic, practical, and inexpensive nature of the surgical looking glass invites its use on a daily basis by the practicing dermatologist. [source] Monodisperse Mesoporous Silica Spheres Inside a Bioactive Macroporous Glass,Ceramic Scaffold,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Renato Mortera In the field of bone tissue engineering, monosized MCM-41 spheres have been incorporated inside a bioactive glass,ceramic macroporous scaffold belonging to the SiO2CaOK2O (SCK) system so obtaining a multiscale hierarchical composite. The MCM-41-SCK system was prepared by dipping the glass,ceramic scaffold into the MCM-41 synthesis solution and was characterized by means of XRD, micro-XRD, N2 sorption and scanning electron microscopy. The MCM-41 spheres inside the scaffold are highly uniform in diameter, as those synthesized in powder form. The adsorption capacity of the composite toward ibuprofen is three times higher than that of the MCM-41-free scaffold, because of the presence of the ordered mesoporous silica. Also the release behavior in SBF at 37,°C is strongly affected by the presence of MCM-41 inside the scaffold macropores. [source] Surface Activation of a Ferrimagnetic Glass,Ceramic for Antineoplastic Drugs GraftingADVANCED ENGINEERING MATERIALS, Issue 7 2010Enrica Vernè A ferrimagnetic glass,ceramic, belonging to the system SiO2,Na2O,CaO,P2O5,FeO,Fe2O3, has been studied as potential carrier for antineoplastic agents, in order to exploit the combination of hyperthermia and chemotherapy. Different material pre-treatments, such as ultrasonic washing, water, or simulated body fluid dipping, were evaluated to promote the surface activation of the glass,ceramic, i.e., the hydroxyl groups formation on it. X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersion spectrometry, and wettability measurements were performed to observe the samples surface modification. The best results in terms of free hydroxyl groups exposition were obtained by dipping the samples in distilled water for 7 days at 37,°C. Two different anticancer drugs were selected in order to test the reactivity of the activated surface: cisplatinum and doxorubicin. The uptake and release of doxorubicin and cisplatinum were evaluated on glass,ceramic powders, by using UV,Visible spectrometry and graphite furnace atomic absorption spectroscopy, respectively. After 1 day of uptake at 37,°C, the quantity of doxorubicin incorporated into the glass,ceramic is 77,±,7 wt%, while only 42,±,9.6 wt% of cisplatinum is grafted onto the material surface. For both antitumoral agents, the maximum drug release after soaking in aqueous solutions at 37,°C was obtained in few hours, with a randomly distributed kinetics trend. [source] Short-Range Structure of Yttrium Alumino-Silicate Glass for Cancer Radiotherapy: Car,Parrinello Molecular Dynamics Simulations,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Jamieson K. Christie We present Car,Parrinello molecular dynamics (CPMD) simulations of yttrium alumino-silicate (YAS) glass. Alumino-silicate glass microspheres are used as vectors of yttrium radioisotopes in cancer radiotherapy; understanding in detail how yttrium is bound within the glass network is important to control the unwanted release of radioactive yttrium in the bloodstream. Our simulations, focused on a specific composition relevant to practical applications, show that silicon and aluminum form a disordered glass network, where Si is mainly four-coordinated, whereas, Al is mainly four- and five-coordinated. Yttrium cations have a network-modifying role, disrupting the alumino-silicate network by breaking Si(Al)O bonds and coordinating the resulting non-bridging oxygens (NBO). The local environment of yttrium in the glass turns out to be rather flexible: between five and eight oxygen atoms, with a marked predominance of NBO, are found coordinated to a central Y cation, leading to a corresponding broad and multimodal distribution of OYO angles. [source] A New Way to Improve Glass-Forming Ability by Controlling the Preparation Conditions of Bulk Metallic GlassADVANCED ENGINEERING MATERIALS, Issue 3 2010Jie Mao Abstract The effects of mold preheating temperature on the glass-forming ability of Zr64.9Al7.9Ni10.7Cu16.5 and Zr47Cu37.5Ag7.5Al8 alloys are investigated using traditional copper mold casting. It is found that there exists an optimum mold temperature for glass-forming alloy systems. For the two Zr-based alloy systems studied the optimum mold temperature is 353,K. This is explained from the perspectives of heat transfer efficiency and the wettability between liquid alloy and copper mold. [source] Transition of Failure Mode and Enhanced Plastic Deformation of Metallic Glass by Multiaxial Confinement,ADVANCED ENGINEERING MATERIALS, Issue 11 2009Fu-Fa Wu Multiple shear bands are formed in a confined metallic-glass specimen under small-punch loading. The intersecting of shear bands and the formation of profuse secondary shear bands are promoted under this confinement; accordingly, the failure mode changes from catastrophic fracture to stable multiple shear banding. Multiaxial confinement is an effective method to stabilize shear banding and further enhance the mechanical performance, especially the plastic deformation capability of metallic glass. These results present a simple step for making shear banding more stable and exploiting the shear-deformation capability of metallic glasses, leading to the toughening of brittle metallic glasses and potentially broadening their applications. [source] Synthesis and Properties of Al-Ni-La Bulk Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 7 2009Juan Mu Al85.5Ni9.5La5 bulk metallic glass (BMG) with a size of 1,mm is synthesized for the first time through a two-step melt treatment. The treatment effectively removes the local structural ordering and high-temperature phases, as well as allowing a high cooling rate. The sample displays good mechanical properties. The compressive fracture strength is about 1180,MPa, which is higher than that of most Mg-based BMGs and Al alloys. [source] Air-Oxidation of a Cu45Zr45Al5Ag5 Bulk Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 5 2009Wu Kai This work studied the oxidation behavior of a Ag-containing Cu,Zr,Al-based amorphous alloy (CZA4-BMG) in dry air at 375,500,°C. The oxidation kinetics of CZA4-BMG obeyed a multi-stage parabolic-rate law, and its steady-state oxidation-rate constants were slightly lower than those of Ag-free amorphous alloy (CZA3-BMG) at the temperature below 450,°C, indicating that the addition of Ag played a partly blocking effect in reducing the available cross-sections of the substrate, which in turn reduced inward diffusion of oxygen, thereby leading to the reduction of oxidation rates for CZA4-BMG. [source] Dependence of Ductility on Free Volume in a Cu-Zr-Based Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 3 2009Feng Jiang Cu46Zr47Al7 bulk metallic glass alloy samples with different free volume states were obtained through thermal treatments such as annealing and quenching. Three-point bending tests were performed to these samples to evaluate their ductility. The results demonstrate that the ductility of BMGs is closely related to the free volume. The reduction in the free volume is the dominant reason for the embrittlement of samples annealed below Tg. In addition, the ductility of embrittled samples can be enhanced by restoring free volume by a short anneals above Tg followed by quenching. [source] Mechanical and Fatigue Behavior of Ca65Mg15Zn20 Bulk-Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2009Gongyao Wang The compression behavior of a Ca65Mg15Zn20 bulk-metallic glass (BMG) was studied. The specimens showed no macroscopic plasticity. They fractured by exploding into many very small pieces. The Vickers hardness of the Ca65Mg15Zn20 BMG was about 1.42 GPa. The fatigue limit for compression,compression fatigue was found to be about 140 MPa after 106 cycles. The fracture strength was inversely proportional to the fracture time. The proposed mechanism of the splitting and shear fracture modes clearly explained these properties. [source] Effects of Temperatures on Inhomogeneous Plastic Flows of a Bulk-Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 11 2008H. Jiang The effects of temperatures on plastic flow and shear banding of a bulk-metallic glass in compression were investigated. Temperature significantly affects the plastic-flow and shear-banding behaviors. With increasing temperatures from the ambient, the plastic deformation tends to become homogeneous both in time and space; while decreasing temperature from the ambient, it tends to be less inhomogeneous in time, but more inhomogeneous in space. Plastic flow is related to shear banding. [source] Consecutive Nucleation Events During Divetrification of Zr52.5Cu17.9Ni14.6Al10Ti5 Bulk Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 11 2008L. Yang Differential scanning calorimetry revealed two exothermal peaks in Zr52.5Cu17.9Ni14.6 -Al10Ti5 bulk metallic glass during divetrification. Analysis of the calorimetry data as well as in-situ X-ray diffraction experiments show that the exothermal peaks correspond to two nucleation events, controlled by interface and long-range diffusion, respectively. [source] Engraving of a Pd77.5Cu6Si16.5 Bulk Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 6 2007G. Fiore A bulk cylinder, 2 mm in diameter, of Pd77.5Cu6Si16.5 amorphous alloys has been obtained by copper moulding. Slices of the sample have been engraved in the undercooled liquid regime just above the glass transition reproducing details of a 5 Euro cent coin by suitably choosing the annealing procedure. The samples remained glassy after processing. [source] Crystallization Kinetics of the (Zr58Ni13.6Cu18Al10.4)Nb1 Bulk Metallic Glass,ADVANCED ENGINEERING MATERIALS, Issue 8 2006D. Qiao The differential thermal analysis (DTA) curve of the (Zr58Ni13.6Cu18Al10.4)Nb1 bulk metallic glass (BMG) shows that there are two exothermic crystallization peaks and two endothermic melting peaks. The BMG has been completely crystallized in the first crystallization peak. X-ray shows that the quenched BMG only includes the glass single phase. The BMG heated to 823 K (between the first and the second crystallization peak) has the precipitation of the cubic NiZr2. The BMG heated to 1003 K (after the second crystallization peak) has the cubic NiZr2, bct NiZr2, and bct CuZr2. HRTEM shows that there are some nano-crystalline phases for the quenched BMG. [source] The use of fire-retardant intumescent mats for fire and heat protection of glass fibre-reinforced polyester composites: Thermal barrier propertiesFIRE AND MATERIALS, Issue 1 2010Everson Kandare Abstract This study investigates the use of integral, hybrid intumescent thermal barriers (mats) to provide surface protection to the core fibre-reinforced polyester composite structural integrity when exposed to a fire or heat source. Glass fibre-reinforced composites protected by intumescent mats/fabrics containing silicate fibres, expandable graphite and in some cases borosilicate glass bounded together by an organic matrix have been evaluated for fire performance under a constant heat flux of 50kW/m2. The effect of insulative fabric thickness as well as chemical composition on the flammability of the resultant hybrid composites is evaluated. Glass fibre-reinforced polyester (GRP) composites without any surface protection have a relatively higher time-to-ignition and peak heat release rate values when compared with core composites protected by insulative fabrics. Thermograms representing the variation of temperature on the reverse side of the hybrid composites with time when exposed to a constant heat flux show that the inclusion of intumescent surface barriers results in retarded temperature increments within the core GRP composites. Copyright © 2009 John Wiley & Sons, Ltd. [source] Geochemistry and petrography of basalt grindstones from the Karak Plateau, central JordanGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2004Brandon G. Watts Seventeen basalt grindstone fragments from central Jordan's Karak Plateau were studied. Most of these artifacts are vesicular or amygdaloidal with calcite as the dominant mineral filling the voids. The major minerals are olivine (with iddingsite rims), plagioclase, clinopyroxene, magnetite, and apatite. Glass is present in some samples. One basalt fragment is quite different in appearance and composition and may have come from flows closer to the Dead Sea. Grindstone fragment compositions plot in the tephrite-basanite and basalt fields. A plot of the concentrations of niobium, zirconium, and yttrium reveal that the sample compositions plot in the "within-plate alkali basalt" and "within-plate tholeiite" fields. The acquisition of basalts for preparing such implements appears to have been random. Some may have been introduced through trade and migration. Archaeological and environmental studies on the Karak Plateau are urgently needed because Jordan's population growth and economic development are destroying many sites and their environmental contexts. © 2004 Wiley Periodicals, Inc. [source] Linear and Nonlinear Optical Properties of Ag Nanowire Polarizing Glass,ADVANCED FUNCTIONAL MATERIALS, Issue 18 2006Q.-Q. Wang Abstract An R2O,B2O3,SiO2 (R,=,Li, Na, K) polarizing glass containing Ag nanorods is prepared by thermal elongation,reduction technology. The transverse and longitudinal plasmon absorption peaks of the embedded Ag nanorods are near 460 and 720,nm, respectively. When the polarization of the laser is parallel to the long axis of the Ag nanorods, the nonlinear absorption coefficient ,,=,0.82,cm,GW,1 and the nonlinear refractive index n2,=,,1.5,×,10,4,cm2,GW,1. When the polarization of light is perpendicular to the long axis of the Ag nanorods ,,=,0.12,cm,GW,1 and n2,=,,7.2,×,10,5,cm2,GW,1 and the appropriate one- and two-photon figures of merit (FOM), W,=,1.6 and T,=,0.16, respectively, are obtained, which satisfies the demand, W,>,1 and T,<,1, for applications in all optical switching, where W is a one-photon FOM, and T is a two-photon FOM. [source] Formation of Thick Porous Anodic Alumina Films and Nanowire Arrays on Silicon Wafers and Glass,ADVANCED FUNCTIONAL MATERIALS, Issue 8 2003O. Rabin Abstract A method for the fabrication of thick films of porous anodic alumina on rigid substrates is described. The anodic alumina film was generated by the anodization of an aluminum film evaporated on the substrate. The morphology of the barrier layer between the porous film and the substrate was different from that of anodic films grown on aluminum substrates. The removal of the barrier layer and the electrochemical growth of nanowires within the ordered pores were accomplished without the need to remove the anodic film from the substrate. We fabricated porous anodic alumina samples over large areas (up to 70 cm2), and deposited in them nanowire arrays of various materials. Long nanowires were obtained with lengths of at least 9 ,m and aspect ratios as high as 300. Due to their mechanical robustness and the built-in contact between the conducting substrate and the nanowires, the structures were useful for electrical transport measurements on the arrays. The method was also demonstrated on patterned and non-planar substrates, further expanding the range of applications of these porous alumina and nanowire assemblies. [source] Processing of Bulk Metallic GlassADVANCED MATERIALS, Issue 14 2010Jan Schroers Abstract Bulk metallic glass (BMG) formers are multicomponent alloys that vitrify with remarkable ease during solidification. Technological interest in these materials has been generated by their unique properties, which often surpass those of conventional structural materials. The metastable nature of BMGs, however, has imposed a barrier to broad commercial adoption, particularly where the processing requirements of these alloys conflict with conventional metal processing methods. Research on the crystallization of BMG formers has uncovered novel thermoplastic forming (TPF)-based processing opportunities. Unique among metal processing methods, TPF utilizes the dramatic softening exhibited by a BMG as it approaches its glass-transition temperature and decouples the rapid cooling required to form a glass from the forming step. This article reviews crystallization processes in BMG former and summarizes and compares TPF-based processing methods. Finally, an assessment of scientific and technological advancements required for broader commercial utilization of BMGs will be made. [source] Ultrahigh-Crystalline-Quality Silicon Pillars Formed by Millimeter-Wave Annealing of Amorphous Silicon on GlassADVANCED MATERIALS, Issue 29 2009Fude Liu Silicon pillars are formed by millisecond-long, single-pulse annealing of 110,GHz millimeter-wave radiation incident upon intrinsic amorphous silicon (a-Si) thin films deposited on glass by hot-wire chemical vapor deposition. The image was taken at a sample tilt angle of 52° for a better 3D view. [source] Failure Waves and their Possible Roles in Determining Penetration Resistance of GlassINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 3 2010Stephan J. Bless 1 High-velocity impact can produce failure waves in glass. Failure waves limit the speed at which a glass target can become comminuted. The resulting time dependence of strength is likely to influence resistance to ballistic penetration. [source] Thermochemical Compatibility of a Seal Glass with Different Solid Oxide Cell ComponentsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 1 2010Manoj K. Mahapatra Thermochemical compatibility of an aluminosilicate glass (SABS-0) with Crofer 22 APU, nickel, and NiTiHf alloy has been studied for solid oxide cell use. Local SABS-0 devitrification occurs near the interfaces of Crofer 22 APU/SABS-0 and Ni/SABS-0 samples. But extensive SABS-0 devitrification is observed at the NiTiHf/SABS-0 interface. The SABS-0 elements diffuse a few microns into the Crofer 22 APU alloy and the nickel, or vice versa. But the SABS-0 and NiTiHf elements diffuse into each other at ,25 ,m. The SABS-0 glass is thermochemically compatible with the Crofer 22 APU and the nickel but not with the NiTiHf alloy. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||