Articoli di riviste: "Glass"

1

Wang, Yu, Xiao Bing Ren e Kazuhiro Otsuka. "Strain Glass: Glassy Martensite". Materials Science Forum 583 (maggio 2008): 67–84. http://dx.doi.org/10.4028/www.scientific.net/msf.583.67.

Testo completo

Abstract (sommario):

“Glass”, a frozen disordered-state, has been found in areas as diverse as amorphous solids, magnetic alloys, ferroelectrics, superconductors, and even in models of biological evolutions. In the present review we introduce a new class of glass–the “strain-glass”, which was discovered very recently. Strain glass is derived from a martensitic system, where the local-strain is frozen in disordered configuration. The first example of strain glass was found in the well-studied Ni-rich Ti50-xNi50+x martensitic system in its “non-transforming” composition regime (x>1.5). Contrasting to the familiar martensitic transition, the strain glass transition is not accompanied by a change in the average structure, or a thermal peak in the DSC measurement. It involves a dynamic freezing process with broken ergodicity, during which nano-sized martensite domains are frozen. More interestingly, the seemingly “non-martensitic” strain glass exhibits unexpected properties: shape memory effect and superelasticity, like a normal martensitic alloy. Strain glass bears a striking similarity with other two classes of glasses: cluster-spin glass and ferroelectric relaxor. These ferroic-transition-derived glasses can be considered as a more general class of glass: ferroic glass. The finding of strain glass may provide new opportunities for martensite research from both fundamental side and application side.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Ma, H., E. Ma e J. Xu. "A new Mg65Cu7.5Ni7.5Zn5Ag5Y10 bulk metallic glass with strong glass-forming ability". Journal of Materials Research 18, n. 10 (ottobre 2003): 2288–91. http://dx.doi.org/10.1557/jmr.2003.0319.

Testo completo

Abstract (sommario):

We report a new Mg-based bulk metallic glass-forming alloy: Mg65Cu7.5Ni7.5Zn5 Ag5Y10. The alloy exhibits a glass-forming ability significantly stronger than all previously discovered Mg-based glass formers. Fully glassy rods 9 mm in diameter can be obtained by using copper mold casting. The critical cooling rate for glass formation was estimated to be <50 Ks−1. The reduced glass-transition temperature (Trg) of the glass was determined to be 0.59.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Drajewicz, Marcin, e Jan Wasylak. "Properties of Glass Surface with Nano-Particles Aluminum Compounds Refined". Advanced Materials Research 39-40 (aprile 2008): 567–70. http://dx.doi.org/10.4028/www.scientific.net/amr.39-40.567.

Testo completo

Abstract (sommario):

New refining technology of soda – lime – silicon glassy surfaces with aluminum compounds nano-molecules has been presented in the present study. Structural definition of aluminum compounds nano-powders exposed to thermal processing, including grain-size analysis has been discussed. Optimal technical and technological parameters of the refining process have been selected. Refining method of soda – lime – silicon glassy surfaces with aluminum compounds nanomolecules assures profitable operational properties of the glass, such as increased bending strength, scratching strength, micro hardness and chemical resistance without deterioration of the optical properties. Nano-molecules were spread onto the heated glass surface, or onto cold glass surface and then heated up to temperatures close to the glass transformation, when nano-molecules penetrate into the glass surface. The layer thicknes as glass operational properties has been tested. From obtained results it can be explained the mechanism the incorporation of nano particles. The received results develop new possibilities with respect to container glass, float glass and glass fibres, as well as to glass processing.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Dutcher, J. R., e M. D. Ediger. "Glass Surfaces Not So Glassy". Science 319, n. 5863 (1 febbraio 2008): 577–78. http://dx.doi.org/10.1126/science.1155120.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Ren, Xiaobing. "Strain glass and ferroic glass - Unusual properties from glassy nano-domains". physica status solidi (b) 251, n. 10 (11 settembre 2014): 1982–92. http://dx.doi.org/10.1002/pssb.201451351.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Zhang, L. C., Z. Q. Shen e J. Xu. "Glass formation in a (Ti, Zr, Hf)–(Cu, Ni, Ag)–Al high-order alloy system by mechanical alloying". Journal of Materials Research 18, n. 9 (settembre 2003): 2141–49. http://dx.doi.org/10.1557/jmr.2003.0300.

Testo completo

Abstract (sommario):

In this work, glass formation under high-energy ball milling was investigated for a (Ti0.33Zr0.33Hf0.33)50(Ni0.33Cu0.33Ag0.33)40Al10 high-order alloy system with equiatomic substitution for early and late transition-metal contents. For comparison, an amorphous alloy ribbon with the same composition was prepared using the melt-spinning method as well. Structural features of the samples were characterized using x-ray diffraction, transmission electron microscopy, and differential scanning calorimetry. Mechanical alloying resulted in a glassy alloy similar to that obtained by melt spinning. However, the glass formation was incomplete, and a small amount of unreacted crystallites smaller than 30 nm in size still remained in the final ball-milled product. Like the melt-spun glass, the ball-milled glassy alloy also exhibited a distinct glass transition and a wide supercooled liquid region of about 80 K. Crystallization of this high-order glassy alloy proceeded through two main stages. After the primary nanocrystallization was completed, the remaining amorphous phase also behaved as a glass, showing a detectable glass transition and a large supercooled liquid region of about 100 K.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Kim, Hwan Sik, Yoo Taek Kim, Gi Gang Lee, Jung Hwan Kim e Seung Gu Kang. "Corrosion of Silicate Glasses and Glass-Ceramics Containing EAF Dust in Acidic Solution". Solid State Phenomena 124-126 (giugno 2007): 1585–88. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.1585.

Testo completo

Abstract (sommario):

The corrosion behavior of glass and glass-ceramics fabricated with silicate glass frit mixed with 50~70 wt% EAF dust in the acidic solution was analyzed by both heavy metal leaching test and microstructural observation. The crystallization temperature, Tc of glassy specimens was around 850 measured by DTA and the heat treatment temperature to crystallize a glassy specimen was selected as 950 / 1 hr. The spinel crystal peaks were found in XRD analysis for the glass containing dust > 60 wt%. For the glass-ceramics, however, the spinel peaks in a specimen containing dust > 50 wt% was found with weak willemite peaks. The glass and glass-ceramic specimens showed the first stage of corroding reaction according to Clark models in acidic solution. The glass-ceramic specimens showed much lower a heavy metal leaching concentration than that of glass specimens in the corrosion test in acidic solution of pH=2.95. Especially, the glass-ceramics containing dust 60 wt% showed a heavy metal leaching concentration of 66 % Pb, 60 % Zn and 98 % Fe lower than that of glass specimens due to crystal phases formed, thermodynamically more stable than a glass network structure. From the leaching test that more Zn ion leached out than Fe ion, the spinel crystal phase [ZnFe2O4] showed better corrosion resistant in the acidic solution than the willemite [Zn2SiO4].

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Woo, Heesu, Jiwan Kim e Seunggu Kang. "Study of Anti-Glare Pattern Forming Process by Glass Etching for Improved Image Quality". Journal of Nanoscience and Nanotechnology 21, n. 3 (1 marzo 2021): 1937–42. http://dx.doi.org/10.1166/jnn.2021.18930.

Testo completo

Abstract (sommario):

In this paper, the anti-glare characteristics of strengthened glass used in the dashboard of automobiles were improved to enhanced the ability of the driver to read the display. To this end, the glass surface was etched with a solution containing HF as a main component. We adjusted the concentration of the etching solution and the etching time as variables, and the transmittance, gloss, haze value, etc. of the etched glass were measured. On the etched glass surface, an irregular pattern mainly containing dioxonium hexa-fluorosilicate crystal phases was generated, and controlling the pattern could improve the anti-glare characteristics of the glass. With higher concentration of the etching solution and longer etching time, the light transmittance, reflectance, and gloss of the etched glass were accordingly lower, while the haze value increased. We discussed the relationship between these property changes and the surface microstructure, pattern components, and roughness of the etched glass.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Contreras Jaimes, Altair T., Gloria Kirste, Christian Patzig, Juliana Martins de Souza e Silva, Jonathan Massera, Natalia Karpukhina, Robert G. Hill, Araceli De Pablos-Martín e Delia S. Brauer. "Phosphate/Silicate Ratio Allows for Fine-Tuning of Bioactive Glass Crystallisation and Glass-Ceramic Microstructure". Glass Europe 2 (3 giugno 2024): 1–26. http://dx.doi.org/10.52825/glass-europe.v2i.1187.

Testo completo

Abstract (sommario):

A combination of XRD, solid-state NMR and state-of-the-art imaging techniques were used to investigate how the calcium orthophosphate/calcium silicate ratio affects the crystallisation of bioactive glasses in the system SiO2-P2O5-CaO-CaF2. In the phosphate-free glass, xonotlite, wollastonite and cuspidine crystallised. From 2.4 mol% P2O5, fluorapatite also formed, while the amount of wollastonite decreased. Crystallisation tendency was low for low phosphate contents, while above 3 mol% P2O5 it increased. The phosphate-free glass showed a volume crystallisation mechanism with constant activation energy. By contrast, the glass with the largest phosphate to silicate ratio showed both volume and surface crystallisation, causing a pronounced decrease in activation energy with crystallisation degree. This work shows that by changing the phosphate/silicate ratio we can determine which crystal phases form, obtaining for example fluorapatite-free or wollastonite-free glass-ceramics, depending on the desired application and properties such as mechanical strength or activity in contact with physiological solutions.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Bhatt, Jatin, Sundaram Kumar e B. S. Murty. "Thermodynamic Model and Synthesis of Bulk Metallic Glass in Cu-Zr-Ti System by Mechanical Alloying". Materials Science Forum 675-677 (febbraio 2011): 189–92. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.189.

Testo completo

Abstract (sommario):

Based on the thermodynamic and topological approach, Cu60Zr30Ti10 has been identified as the best bulk metallic glass forming composition in Cu-Zr-Ti system. Bulk metallic glass has been successfully produced using mechanical alloying of elemental blends and consolidation of the resulting glassy powders into pellets of 8 mm diameter. Dry sliding wear of glassy pellets at different annealed states showed that the relaxed metallic glass has excellent wear resistance.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Kim, Hyeong-Jun, Jewon Park, Hyein Na, Hyung Mi Lim e Gabin Chang. "Improvement of Flame-Retardant Performance of Polyurethane Foam Coated with Water Glass". Fire Science and Engineering 34, n. 2 (30 aprile 2020): 7–13. http://dx.doi.org/10.7731/kifse.43a374e9.

Testo completo

Abstract (sommario):

In this study, water glass was applied as a coating material to a rigid polyurethane foam to improve the flame-retardant properties of the foam. The heat release rate of the cone calorimeter of the urethane foam, in which the inorganic water-glass coating layer was applied, decreased rapidly. The water glass coated on the polyurethane surface formed a glassy foam by foaming with water, which did not escape during the vitrification reaction when the foam or glass was heated. The glassy foam formed on the polyurethane foam became a fire-resistant insulation layer that inhibited the combustion of the polyurethane foam for more than 10 min. Water glass was found to improve the flame-retardant properties of the rigid polyurethane foam.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Vila-Costa, A., J. Ràfols-Ribé, M. Gonzalez-Silveira, A. Lopeandía, J. Ll Tamarit e J. Rodríguez-Viejo. "Multiple glass transitions in vapor-deposited orientational glasses of the most fragile plastic crystal Freon 113". Physical Chemistry Chemical Physics 21, n. 20 (2019): 10436–41. http://dx.doi.org/10.1039/c9cp00976k.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Gautam, C. R., Devendra Kumar, Om Parkash e O. P. Thakur. "Dielectric Properties of La2O3 Doped Composite (PbxSr1−x)TiO3 Borosilicate Glass Ceramic". Journal of Ceramics 2013 (5 dicembre 2013): 1–9. http://dx.doi.org/10.1155/2013/879758.

Testo completo

Abstract (sommario):

Ferroelectric (PbxSr1−x)TiO3 (PST) perovskite phase has been crystallized in borosilicate glassy matrix with a suitable choice of composition and heat treatment schedule. La2O3 is a donor dopant for PST and can make it semiconducting. Dispersion of semiconducting perovskite phase in insulating glassy matrix in glass-ceramic samples may lead to the formation of space charge polarization around crystal-glass interface, leading to a high value of effective dielectric constant, εr. Therefore, with the aim of the developing glass ceramics with high dielectric constant, glasses in the system 64[(PbxSr1−x)O·TiO2]-25[2SiO2·B2O3]-5[K2O]-5[BaO]-1[La2O3] have been prepared (0.5≤x≤1). It is found that the addition of La2O3 strongly affected the crystallization and dielectric behavior of glass-ceramic with PST perovskite phase. All glass ceramic samples show a diffuse broad Curie peak in their εr versus T plots. Curie peak temperature, Tc, depends on compositions of the glass-ceramic samples as well as frequency of measurements.

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Verma, Arvind Kumar, Anchal Srivastava, R. K. Shukla e K. C. Dubey. "Thermal Behavior of Chalcogenide glasses Te90Se10 and Se90Te10". SAMRIDDHI : A Journal of Physical Sciences, Engineering and Technology 7, n. 02 (25 dicembre 2015): 113–18. http://dx.doi.org/10.18090/samriddhi.v7i2.8636.

Testo completo

Abstract (sommario):

In the present research work melt quenching method has been adopted to prepare the glassy Te-rich (Te90Se10) and Se-rich (Se90Te10 ) Chalcogenide at a pressure of 10-2 Torr with constant Temperature at 1000°C for 8 hours. Devitrification characteristics of the pure glassy Chalcogenide Te90Se10 and Se90Te90 were investigated by using Differential scanning Calorimetry (DSC) 4000 Perkin Elmer. All the measurements carried out at fixed heating rate 10 0C/min under non-isothermal conditions. The Glass transition temperature (Tg) and other thermal properties were examined by temperature modulated differential scanning Calorimetry at 40 oC to 445 oC. Glass transition temperature (Tg) represents the strength or rigidity of the glass structure. Tg affords valuable information on the thermal stability of the glassy state but Tg alone does not give any information on the glass forming tendency. The difference of the Peak crystallization temperature (Tp) and Glass transition temperature (Tg) is a strong indication of the thermal stability. The higher the value of Tc and Tg the greater is the thermal stability. Glass transition temperature (Tg=2160C) of Tellurium rich (Te90Se10) is more than Glass transition temperature (Tg=730C) of Selenium rich (Se90Te90) due to semi metallic nature of Tellurium. The difference of (Tp-Tg) is a strong indicator of both the thermal stability and Glass forming ability (GFA). Higher the value of (Tp-Tg), higher is the thermal stability and GFA because higher values of this difference indicate more kinetic resistance to the crystallization. Glass forming ability (GFA) and thermal stability of Te90Se10 is greater than Se90Te90. For memory and switching materials, glass thermal stability and GFA parameters are very important. Intensity of Se-rich (Se90Te10) is more than Te-rich (Te90Se10) and both samples are polycrystalline in nature.

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Sharifi, Soheil, e Jahanbakhsh Mashaiekhy Asl. "Secondary Relaxation inside the Glass". ISRN Materials Science 2011 (20 luglio 2011): 1–10. http://dx.doi.org/10.5402/2011/764874.

Testo completo

Abstract (sommario):

The physical properties of the glass depend on the procedure used to produce the glass. In particular, if the glass is obtained through the variation of external thermodynamic parameters, the specific way in which the parameters are varied (thermodynamic history) has influence on the final properties. In this work, we studied the effect of thermodynamic history on secondary relaxation inside the glassy state on different molecular glass forming, namely, PPGE(poly[(phenyl glycidyl ether)-co-formaldehyde]), 1,18-bis (p methoxyphenyl) cyclohexane (BMPC), poly(propylene glycol)—(PPG400), phenolphthalein-dimethyl-ether(PDE), Poly(vinyl acetate) (PVAc), and poly(bisphenol A-co-epichlorohydrin) glycidyl end-capped (DGEBA). We found secondary relaxation change with thermodynamic history and depends on the value of the activation volume which activation entropy of secondary relaxation inside the glassy state. Also, we found most of the JG secondary relaxation change with thermodynamic history and most of the Non-JG secondary relaxation are not sensitive.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

XIA, L., C. L. JO e Y. D. DONG. "GLASS FORMING ABILITY OF HARD MAGNETIC Nd55Al20Fe25 BULK GLASSY ALLOY WITH DISTINCT GLASS TRANSITION". International Journal of Modern Physics B 19, n. 22 (10 settembre 2005): 3493–500. http://dx.doi.org/10.1142/s021797920503219x.

Testo completo

Abstract (sommario):

Nd 55 Al 20 Fe 25 bulk sample was prepared in the shape of rods 3 mm in diameter by suction casting. The sample exhibits typical amorphous characters in XRD pattern, distinct glass transition in DSC traces and hard magnetic properties. The distinct glass transition, which is invisible in DSC traces of previously reported Nd — Al — Fe ternary BMGs, allows us to investigate the glass forming ability (GFA) of Nd 55 Al 20 Fe 25 alloy using the reduced glass transition temperature Trg and the recently defined parameter γ. However, it is found that the obtained diameter of the Nd 55 Al 20 Fe 25 glassy rod is much larger than the critical section thickness of the BMG predicted by either Trg or γ. The microstructure of Nd 55 Al 20 Fe 25 as-cast rod was studied and the apparent GFA of the alloy was supposed to be enhanced by the metastable nano-precipitates dispersed within the glassy matrix.

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Buonsante, P., F. Massel, V. Penna e A. Vezzani. "Glassy features of a Bose glass". Laser Physics 18, n. 5 (maggio 2008): 653–58. http://dx.doi.org/10.1134/s1054660x08050174.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Gomes Fernandes, Roger, Raschid Al-Mukadam, Hansjörg Bornhöft, Stefan Reinsch, Ralf Müller, Susanne Selle e Joachim Deubener. "Viscous Sintering of Acid Leached Glass Powders". Glass Europe 1 (23 novembre 2023): 37–53. http://dx.doi.org/10.52825/glass-europe.v1i.681.

Testo completo

Abstract (sommario):

The process of viscous flow sintering is a phenomenon that is closely linked to the surface properties of the glass particles. In this work, we studied the extreme case of acid-leaching of soda-lime-silicate glass beads of two different particle size distributions and its effects on non-isothermal viscous sintering of powder compacts. Depth profiling of the chemical composition after leaching revealed a near-surface layer depleted in alkali and alkaline earth ions, associated with concurrent hydration as mass loss was detected by thermogravimetry. Heating microscopy showed that acid treatment of glasses shifted the sinter curves to higher temperatures with increasing leaching time. Modelling of the shrinkage with the cluster model predicted a higher viscosity of the altered surface layer, while analysis of the time scales of mass transport of mobile species (Na+, Ca2+ and H2O) during isochronous sintering revealed that diffusion of Na+ can compensate for concentration gradients before sintering begins. Also, exchanged water species can diffuse out of the altered layer, but the depletion of Ca2+ in the altered surface layer persists during the sinter interval, resulting in a glass with higher viscosity, which causes sintering to slow down.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Vaiborisut, Napaporn, Chanittha Chunwises, Dararat Boonbundit, Sirithan Jiemsirilers e Apirat Theerapapvisetpong. "Effect of the Addition of ZrSiO₄ on Alkali-Resistance and Liquidus Temperature of Basaltic Glass". Key Engineering Materials 766 (aprile 2018): 145–50. http://dx.doi.org/10.4028/www.scientific.net/kem.766.145.

Testo completo

Abstract (sommario):

Basalt fiber has been used as a reinforced material in cement-based materials because it has higher mechanical strength and cheaper than common silicate based glass-fibers. However, silicate-based glass fibers have low alkali resistance especially in cement matrix composite. In this work, we studied the improvement of alkali resistance by addition of zirconium silicate (ZrSiO4) in original basalt glass composition. The batch of basalt glass with additional ZrSiO4 contents of 0.00, 2.50, 5.00, 7.50 and 10.00 wt% were melted at 1500 °C. The liquidus temperature (TL) is important in for the fiber glass manufacturing. It need to formulate glass composition which requires a lower melting temperature and is crystallization resistant. TL as a function of composition is usually determined experimentally. In this study, glassy phase was determined by X-ray Diffraction (XRD). The glass transition temperature (Tg), the crystallization temperature (Tc) and TL were analyzed by Differential Thermal Analysis (DTA). The results found that the addition of ZrSiO4 in a basalt glass batch increased Tg while Tc of each sample was closed to original basalt fiber. Moreover, the alkali resistance of these glasses increased with an increasing of ZrSiO4 content. However, excessive ZrSiO4 contents (7.50 and 10.00 wt%) resulted in crystallization of ZrO2 which separated from glassy phase.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Yan, Qian, Chang, Lu e Miyakoshi. "The Effect of Glass Fiber Powder on the Properties of Waterborne Coatings with Thermochromic Ink on a Chinese Fir Surface". Polymers 11, n. 11 (23 ottobre 2019): 1733. http://dx.doi.org/10.3390/polym11111733.

Testo completo

Abstract (sommario):

In this study, the effect of glass fiber powder on the properties of waterborne coatings with thermochromic ink was investigated, using Chinese fir board as the base material and temperature-sensitive thermochromic waterborne coatings with thermochromic ink as the paint base. The concentration of glass fiber powder was determined when the microstructure, optical properties, mechanical properties, liquid resistance, and heat preservation effect were the best. The results showed that the paint film with glass fiber powder concentration of 1.0% to 7.0% had better discoloration performance. With an increase of the glass fiber powder concentration, the gloss of the paint film decreased gradually, and when the concentration of glass fiber powder was 0% to 5.0%, the gloss of the paint film was better. The concentration of glass fiber powder had no effect on the adhesion, impact resistance, and liquid resistance. In the first 2.5 min, the temperature value of the waterborne coating with 3.0% glass fiber powder was higher than that without glass fiber powder, which has a certain heat preservation effect. When the glass fiber powder content was 3.0%, the microstructure of paint film was the best. The composition of paint film with different glass fiber powder concentrations was not different and the discoloration performance of paint film with heat preservation effect was not affected by time. The analysis showed that the waterborne coating with 3.0% glass fiber powder had the best comprehensive performance. This work provides a technical reference for the industrialization of heat preservation and thermochromic coating on wood.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

de Oliveira, Vera Lúcia Praxedes, Marcelo Henrique Prado da Silva, Eduardo de Sousa Lima, Claudinei dos Santos e Luis Henrique Leme Louro. "Effect of Glassy Phase Additions to Zirconia on its Sintering Behavior and Microstructure". Materials Science Forum 727-728 (agosto 2012): 935–39. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.935.

Testo completo

Abstract (sommario):

TZP yttria-stabilized zirconia powder was mixed with two types of glasses as sintering additives: CAS glass and a bioactive glass. These additions were designed toward the material applications as bioceramics. The glassy phase was chosen to promote liquid phase sintering at lower temperature, when compared to pure material. This procedure contributed to reduce the fabrication costs while keeping the material biocompatibility. Each type of glass was added in concentrations of 1, 3, and 5 wt%. The prepared powders were uniaxially pressed at 50 MPa, and then sintered at 1300°C for two hours. The sintering behavior was evaluated by measuring the final sintered densities. It was found that the samples with bioactive glass additions were denser than those with CAS glass. Zirconia TZP powders without glassy additions would not sinter in this temperature. The microstructure of the sintered samples was characterized by SEM and XRD. The sintered ceramics exhibited both submicrometric and uniform grains. The analyzed grain sizes were slightly lower for the samples with CAS additions than for those with bioactive glass additions.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

da Silva, Antônio Carlos, S. C. Santos e Sonia Regina Homem de Mello-Castanho. "Transition Metals in Glass Formation". Materials Science Forum 727-728 (agosto 2012): 1496–501. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1496.

Testo completo

Abstract (sommario):

The structure of silicate glasses gets its charge stability through SiO2, R2O3, R2+and R+groups arrangement. In these glassy structures, transition metals are usually used as dopants in small amounts. However, in soda-lime glass systems, transition metals can take part in the glassy network in larger quantities as secundary former or modifier, insted R2+groups, if the charge balance conditions are made favorable by R2O3groups additions. This paper studies transition metals (Cr, Ni, Fe, Cu, Zn, Pb, Ru) soda-lime-borosilicate glass network incorporation. This process was applied for many kinds of toxic metals containing vitrification waste. The glasses were obtaind by melt at temperature of 1300°C, and characterized by FT-IR and XRD techinics. The chemical stability was evaluated by hydrolytic attack test. The glasses showed a high chemistry and environmental stability like the soda-lime glass.Keywords: glass structure, electroplating waste, e-waste, nanowaste.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Ramamurthy, Sundar, Brian C. Hebert e C. Barry Carter. "Olivine-MgO interfaces produced by crystallization of glass fulms on single-crystal MgO substrates". Proceedings, annual meeting, Electron Microscopy Society of America 53 (13 agosto 1995): 342–43. http://dx.doi.org/10.1017/s0424820100138087.

Testo completo

Abstract (sommario):

Glassy silicates are present at grain boundaries in almost all liquid-phase sintered ceramic oxides. In many cases, the amorphous-crystalline interfaces in the sintered microstructure can be modified by inducing crystallization of the glassy phase. The intergranular phases in polycrystalline MgO are typically silicates with cations of calcium, magnesium and iron in the silicate network. A systematic approach to study the crystallization behavior of glass-MgO interfaces has been attempted in the present study. Following the work by Mallamaci in which crystallization of a silicate glass in contact with A12O3 was studied, devitrification of glass in contact with single-crystal MgO has been investigated. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to characterize the resulting microstructures.A pellet of Mg2SiO4 (forsterite) prepared by hot-pressing MgO and SiO2 powders was used as the target for depositing glass films onto single-crystal MgO substrates by pulsed-laser deposition (PLD). Glass films with the composition of olivine.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Kasuga, Toshihiro, Emiko Ueno e Akiko Obata. "Preparation of Apatite-Containing Calcium Phosphate Glass-Ceramics". Key Engineering Materials 330-332 (febbraio 2007): 157–60. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.157.

Testo completo

Abstract (sommario):

A new type of glass-ceramic for novel dental fillers, which require excellent chemical durability, was investigated. A 40CaO-5CaF2-25TiO2-30P2O5 (in mol%) glass-ceramic was newly suggested. The glass-ceramic was prepared by a conventional two-step heating method. The resulting glass-ceramic included Nasicontype-CaTi4(PO4)6, titanium phosphates, such as (TiO)2P2O7 and Ti(PO3)3, and TiO2 (anatase) with apatite crystal, which was induced by incorporation of fluorine. In the glass-ceramic, dissolution by acid-treatment was strictly controlled. The excellent chemical durability of the glass-ceramic was suggested to originate from increase in the amount of the crystalline phases and a high content of titanium constituent in the residual glassy phase.

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Zhu, Sheng Li, Guo Qiang Xie, Akihisa Inoue, Zhen Duo Cui, Xian Jin Yang e Wei Zhang. "Effects of Minor Additions on Ni- and Be-Free Ti-Based Bulk Glassy Alloys". Materials Science Forum 833 (novembre 2015): 79–84. http://dx.doi.org/10.4028/www.scientific.net/msf.833.79.

Testo completo

Abstract (sommario):

We investigated the effects of addition elements (Sn, Al, Si, Ag, Fe, Cr) with a small amount on the glass-forming ability, thermal stability and mechanical properties of the Ti-Zr-Cu-Pd glassy alloy system. The results revealed that minor Sn addition improved the glass-forming ability, thermal stability and plasticity, Si addition enlarged the supercooled liquid region, and Fe addition improved the plasticity, while minor additions of Si, Ag, Fe, and Cr lowered the glass-forming ability, and Al and Cr additions were harmful to the plasticity of the Ti-Zr-Cu-Pd glassy alloy system.

Gli stili APA, Harvard, Vancouver, ISO e altri

26

PARK, JONGEE, e ABDULLAH OZTURK. "BIOACTIVITY OF APATITE–WOLLASTONITE GLASS-CERAMICS PRODUCED BY MELTING CASTING". Surface Review and Letters 20, n. 01 (febbraio 2013): 1350010. http://dx.doi.org/10.1142/s0218625x13500108.

Testo completo

Abstract (sommario):

Glass-ceramics containing only apatite and wollastonite crystals were produced in the system MgO-CaO-SiO2-P2O5-F by the melt casting process. The bioactivity of the glass-ceramics was determined by immersing the glass-ceramics in a simulated body fluid (SBF) and by assessing the resulting apatite formation on the free surface after various immersion durations. A 12-μm-thick apatite layer formed on the surface of the glass-ceramic containing only apatite crystals after 20 days immersion in SBF. However, the thickness of the apatite layer formed on the surface of the glass-ceramic containing apatite and wollastonite crystals was 1 μm. Results have shown that the bioactivity of glass-ceramic depends strongly on the type of crystal(s) developed during the glass-ceramic process and their proportion in the glassy matrix.

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Cruz, Rui, João Alexandre da Cruz Ranita, José Macaira, Fernando Ribeiro, Ana Margarida Batista da Silva, José M. Oliveira, Maria Helena F. V. Fernandes, Helena Aguilar Ribeiro, Joaquim Gabriel Mendes e Adélio Mendes. "Glass–Glass Laser-Assisted Glass Frit Bonding". IEEE Transactions on Components, Packaging and Manufacturing Technology 2, n. 12 (dicembre 2012): 1949–56. http://dx.doi.org/10.1109/tcpmt.2012.2212195.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Hammond, Andrew P., e Eric I. Corwin. "Experimental observation of the marginal glass phase in a colloidal glass". Proceedings of the National Academy of Sciences 117, n. 11 (3 marzo 2020): 5714–18. http://dx.doi.org/10.1073/pnas.1917283117.

Testo completo

Abstract (sommario):

The replica theory of glasses predicts that in the infinite dimensional mean field limit, there exist two distinct glassy phases of matter: stable glass and marginal glass. We have developed a technique to experimentally probe these phases of matter using a colloidal glass. We avoid the difficulties inherent in measuring the long time behavior of glasses by instead focusing on the very short time dynamics of the ballistic to caged transition. We track a single tracer particle within a slowly densifying glass and measure the resulting mean squared displacement (MSD). By analyzing the MSD, we find that upon densification, our colloidal system moves through several states of matter. At lowest densities, it is a subdiffusive liquid. Next, it behaves as a stable glass, marked by the appearance of a plateau in the MSD whose magnitude shrinks with increasing density. However, this shrinking plateau does not shrink to zero; instead, at higher densities, the system behaves as a marginal glass, marked by logarithmic growth in the MSD toward that previous plateau value. Finally, at the highest experimental densities, the system returns to the stable glass phase. This provides direct experimental evidence for the existence of a marginal glass in three dimensions.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

SURYANARAYANA, C., e SATYAJEET SHARMA. "GLASS FORMATION IN MECHANICALLY ALLOYED Fe-BASED SYSTEMS". Functional Materials Letters 02, n. 04 (dicembre 2009): 147–55. http://dx.doi.org/10.1142/s1793604709000727.

Testo completo

Abstract (sommario):

Rapid solidification processing of metallic melts has been traditionally employed to synthesize metallic glasses in several alloy systems. However, in recent years, solid-state processing methods, and more specifically, mechanical alloying, have become popular methods to synthesize glassy phases in metallic alloy systems. Although a large number of criteria have been developed to identify alloy compositions that can be solidified into the glassy state, very few attempts have been made to predict the glass-forming ability by solid-state processing methods. To evaluate if some clear criteria could be developed to predict glass formation by solid-state processing methods and to understand the mechanism of glass formation, mechanical alloying of powder blends was conducted on several Fe -based alloy systems. Three different aspects of glass formation are specifically discussed in this paper. One is the development of a criterion for identifying glass-forming systems from phase diagram features, the second is the process of mechanical crystallization (formation of a crystalline phase on continued milling of the amorphous powders obtained by mechanical alloying), and the third is the novel phenomenon of lattice contraction during amorphization. It was shown that the conditions under which a glassy phase is formed by mechanical alloying are different from the solidification methods.

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Wang, Yi Ming, Li Jing Zheng e Shu Jie Pang. "Formation and Mechanical Properties of Mg-Cu-Al-Gd Bulk Metallic Glass Composites". Materials Science Forum 650 (maggio 2010): 290–94. http://dx.doi.org/10.4028/www.scientific.net/msf.650.290.

Testo completo

Abstract (sommario):

The effect of Al addition to Mg65Cu25Gd10 glassy alloy on the microstructure, thermal properties and mechanical properties were investigated. The Mg65Cu25-xAlxGd10 (x=1-7at. %) bulk metallic glass composites were formed by copper mold casting, and the fraction and size of the crystalline phases in the glassy matrix changed with the Al content. The Mg65Cu24Al1Gd10 glass composite consisted of a small amount of crystalline phases in the glassy matrix possesses high compressive strength up to about 850 MPa.

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Modgil, Vivek, e V. S. Rangra. "Effect of Sn Addition on Thermal and Optical Properties of Pb9Se71Ge20-xSnx (8≤x≤12) Glass". Journal of Materials 2014 (27 marzo 2014): 1–8. http://dx.doi.org/10.1155/2014/318262.

Testo completo

Abstract (sommario):

Study of thermal and optical parameters of Pb9Se71Ge20-xSnx (8≤x≤12) glass has been undertaken. Crystallization and glass transition kinetics has been investigated under nonisothermal conditions by DSC technique. Phase separation has been observed in the material and is investigated by taking the XRD of annealed bulk samples. The material possesses good glass forming ability, high value of glass transition temperature about 420 K, and glass stability. Optical band gap and other optical constants such as refractive index and extinction coefficient have been determined. The isoelectronic substitution of Ge with Sn in the glassy system reduces the optical band gap and enhances the thermal properties.

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Kasuga, Toshihiro, Miwako Terada, Masayuki Nogami e Mitsuo Niinomi. "Machinable calcium pyrophosphate glass-ceramics". Journal of Materials Research 16, n. 3 (marzo 2001): 876–80. http://dx.doi.org/10.1557/jmr.2001.0107.

Testo completo

Abstract (sommario):

Glass-ceramics containing a large amount of calcium pyrophosphate (β–Ca2P2O7) crystal were prepared via crystallization and sintering; compacts of a calcium phosphate glass powders with a composition of 60CaO · 30P2O5 · 5TiO2 · 5Na2O (in mol%) were heated for 3–6 h at 850 °C in air. The compacts were densified by the viscous flow of the glassy phases during heating. The calcium phosphate glass-ceramics were found to show a bending strength of approximately 100 MPa, and they were easy to machine, as confirmed by a drilling test using a conventional carbide tool. The machinability is thought to arise from the microstructure consisting predominantly of the interlocking and platelike β–Ca2P2O7 precipitated in the glass.

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Cho, Jihyun, e Hwan Hee Kim. "The Role of Lead Glass Plate and Correlation Analysis of Raw Materials in Mireuksa Temple Site, Iksan". Journal of Conservation Science 38, n. 5 (31 ottobre 2022): 482–95. http://dx.doi.org/10.12654/jcs.2022.38.5.10.

Testo completo

Abstract (sommario):

We interpreted the role and meaning of nine lead glass plates excavated from the Mireuksa Temple site in Iksan and investigated their materials. Glass plates were excavated from all areas of the site, especially around Geumdangji and the eastern pagoda. The lead glass was presumed to have been partially installed in the symbolic space of the temple. Quantitative analysis of the lead glass (ICP system) determined that PbO comprised 74.2 to 79.5% wt. of the glass (average 76.6% wt.), which was higher than that reported for the glass in prior studies (approximately 70% wt.). Regarding the correlation between lead isotope ratios and trace elements in the glass, the Baekje and Silla cultures showed clear distinctions, and the origin of other materials was confirmed for each culture. Therefore, a constant composition ratio was maintained when producing lead glass and procuring raw materials through various routes. The above results can provide data for understanding the technical systems regarding ancient glassy materials and reproducing them using future manufacturing technologies.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Kim, Jong Sun, Kyung Hwan Yoon e Julia A. Kornfield. "Measurement of Stress-Optical Coefficients of COC’s with Different Composition". Key Engineering Materials 326-328 (dicembre 2006): 183–86. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.183.

Testo completo

Abstract (sommario):

Rheo-optical and mechanical properties of Cyclic Olefin Copolymers(COC’s) with different composition have been investigated across the glass transition temperature. Accurate measurement of stress or strain-optical coefficients and elastic modulus data across the glass transition are essential for predicting optical anisotropy in many optical products like pickup lenses and waveguides in LCD backlight unit since the material of these products have both flow and thermal history from the melt to glass. To obtain stress-optic behavior in the wide frequency region including rubbery, glassy and glass transition regime, extensional bar-type device was used. A shear-sandwich tool was used in the melt region. Master curves for modulus, stress-optical and strain-optical coefficients have been obtained in wide frequency region. The stress-optical coefficients of COC’s with mol fraction of norbornene, 60 ~ 70%, showed almost constant between -8 and -9 Br at glassy region and between +920 and +1,160 Br in the melt region. Even though the glass transition temperature showed the difference of 35, the stress-optical coefficients of COC’s with different composition showed almost same extreme values

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Mallamaci, Michael P., James Bentley e C. Barry Carter. "In situ crystallization of silicate glass films deposited on α-Al2O3". Proceedings, annual meeting, Electron Microscopy Society of America 51 (1 agosto 1993): 928–29. http://dx.doi.org/10.1017/s0424820100150472.

Testo completo

Abstract (sommario):

Polycrystalline alumina compacts often contain amorphous films at grain boundaries and triple junctions as a result of the liquid-phase sintering process. An anorthite-based composition (CaAl2Si2O8) is typical of the glassy phases observed in these materials. With appropriate heat treatments the glass phase can be crystallized, which can influence the properties of the bulk material. Deposition of a thin film of glass on single-crystal α-Al2O3 is being used to study the influence of specific crystallographic orientations on the alumina-glass interface properties. Vapor-phase growth of glass on different orientations of α-Al2O3 has been accomplished previously and, through subsequent thermal treatments, the alumina was shown to facet preferentially when in contact with a glassy phase. In the present study, calcium-aluminosilicate glass films were grown on single-crystal α-Al2O3 at relatively low substrate temperatures (<950°C) by pulsed-laser deposition. These films were then heated in the electron microscope to determine the effect of α-Al2O3 crystallography on crystallization of calcium-aluminosilicate glasses.

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Li, Jianwei. "Thermomechanical constitutive equations for glass and numerical simulation on automobile glass forming technology". Glass Technology: European Journal of Glass Science and Technology Part A 63, n. 4 (2022): 122–28. http://dx.doi.org/10.13036/17533546.63.4.006.

Testo completo

Abstract (sommario):

To establish a comprehensive numerical model for automotive glass forming, firstly, this paper conducts material tests of 3·2 SG glass to obtain detailed material properties. Through thermal expansion experiments, the thermal expansion coefficients including glassy and liquid states are obtained; then by using three-point bending stress relaxation and differential scanning calorimetry experiments, the stress relaxation and structural relaxation properties of the glass are obtained. Finally, a comparison analysis of the simulation and the actual spherical deviation for an actual automobile glass product is carried out. The result shows that the product simulation and the actual product spherical deviation correspond. The maximum value of the spherical deviation is within 0·94 mm between simulation and the actual product spherical deviation. The accuracy can meet the design requirements, and the established numerical model is reliable.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Reis, Ana Karoline dos, Francisco Maciel Monticelli, Roberta Motta Neves, Luis Felipe de Paula Santos, Edson Cocchieri Botelho e Heitor Luiz Ornaghi Jr. "Creep behavior of polyetherimide semipreg and epoxy prepreg composites: Structure vs. property relationship". Journal of Composite Materials 54, n. 27 (22 maggio 2020): 4121–31. http://dx.doi.org/10.1177/0021998320927774.

Testo completo

Abstract (sommario):

In the present study, the creep behavior of polyetherimide semipreg and epoxy prepreg composites was studied using dynamic mechanical analyzer and focused on structure vs. property relationships in glassy, glass transition, and elastomeric regions. The main contribution to the field is to study pre-impregnated materials concerning creep behavior, mainly based on different analytical models, and microstructure. Two different reinforcements were used (carbon fiber and glass fiber) for each matrix. Findley, Burger, and Weibull analytical models were applied with an excellent fit for the most of them. The impregnation quality, verified by C-scan and the void content by acid digestion, shows different impregnation behaviors, mainly for epoxy/CF, which also influenced molecular motion behavior. The creep behavior was mainly influenced by matrix type than reinforcement architecture and void content. In addition, the creep was higher for epoxy in the glassy region; however, in the glass transition region, higher deformation was found for polyetherimide composites. Previous behavior is mainly attributed to higher energy storage in the glassy region which plays a significant role in the dissipation (glass transition energy), resulting in the energy loss or the drop of storage modulus in a narrow temperature range – more abrupt. This behavior was corroborated by time-temperature superposition curves in which the low deformation obtained for polyetherimide composites at low temperatures is maintained only until the glass transition temperature. Epoxy composites showed a higher initial creep deformation, but the values were almost constant with temperature, even when the temperature passes by the glass transition temperature.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Jabed, Akib, M. Nabil Bhuiyan, Waseem Haider e Ishraq Shabib. "Distinctive Features and Fabrication Routes of Metallic-Glass Systems Designed for Different Engineering Applications: A Review". Coatings 13, n. 10 (26 settembre 2023): 1689. http://dx.doi.org/10.3390/coatings13101689.

Testo completo

Abstract (sommario):

Materials with a disordered atomic structure, often termed glassy materials, are the focus of extensive research due to the possibility of achieving remarkable mechanical, electrochemical, and magnetic properties compared to crystalline materials. The glassy materials are observed to have an improved elastic modulus combined with a higher strength and hardness. Moreover, better corrosion resistance in different mediums is also observed for glassy solids, which is difficult to attain using conventional crystalline materials. As a result, the potential applications of metallic-glass systems are continually increasing. Amorphous materials are usually divided into two categories based upon their size. Materials with a thickness and diameter larger than the millimeter (mm) scale are termed as bulk metallic glass (BMG). However, the brittle nature of the bulk-sized samples restricts the size of metallic-glass systems to the micron (µm) or nanometer (nm) range. Metallic glasses with a specimen size in the scale of either µm or nm are defined as thin-film metallic glass (TFMG). In this review, BMGs and TFMGs are termed as metallic glass or MG. A large number of multi-component MGs and their compositional libraries reported by different research groups are summarized in this review. The formation of a multicomponent metallic glass depends on the constituent elements and the fabrication methods. To date, different unique fabrication routes have been adopted to fabricate BMG and TFMGs systems. An overview of the formation principles and fabrication methods as well as advantages and limitations of conventional MG fabrication techniques is also presented. Furthermore, an in-depth analysis of MG inherent properties, such as glass forming ability, and structural, mechanical, thermal, magnetic, and electrochemical properties, and a survey of their potential applications are also described.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Ban, Kazunari. "Lamp Glass (Quartz Glass)". JOURNAL OF THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN 69, n. 1 (1985): 8–10. http://dx.doi.org/10.2150/jieij1980.69.1_8.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

40

LI, Yan-Wei, Zhao-Yan SUN e Li-Jia AN. "Glass and Glass Transition". University Chemistry 31, n. 3 (2016): 1–10. http://dx.doi.org/10.3866/pku.dxhx20160301.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Lehmann, Jean-Claude. "Glass and glass products". Europhysics News 37, n. 6 (novembre 2006): 23–27. http://dx.doi.org/10.1051/epn:2006602.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Wada, Takeshi, Fengxiang Qin, Xinmin Wang, Masahiro Yoshimura, Akihisa Inoue, Naota Sugiyama, Rieko Ito e Nobuhiro Matsushita. "Formation and bioactivation of Zr-Al-Co bulk metallic glasses". Journal of Materials Research 24, n. 9 (settembre 2009): 2941–48. http://dx.doi.org/10.1557/jmr.2009.0348.

Testo completo

Abstract (sommario):

A Cu- and Ni-free Zr-based metallic glass with high glass-forming ability was found in the Zr-Al-Co ternary system. The eutectic Zr56Al16Co28 alloy could be cast into glassy cylindrical rods with diameters up to 18 mm. The glassy alloy exhibited high tensile fracture strength of 1830 MPa and low Young's modulus of 83 GPa in conjunction with better corrosion resistance compared with the glassy Zr57Nb5Al10Ni12.6Cu15.4 in a simulated body fluid. Hydrothermal-electrochemical treatment in the aqueous 5M-NaOH solution resulted in the formation of amorphous sodium cobaltate layer on the surface of glassy Zr56Al16Co28 alloy. Hydroxyapatite was spontaneously formed on the surface of the alloy, indicating bioactivity after surface modification. The discovery of a Cu- and Ni-free Zr-based metallic glass with a critical diameter larger than 1 cm in conjunction with excellent mechanical properties, superior corrosion resistance, and good bioactivity may open up the application field as biomaterials.

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Yue, Li Jie, Jin Sheng Han e Kun Xie. "The Microalloying Effects in Cu-Based Bulk Metallic Glasses". Materials Science Forum 688 (giugno 2011): 407–12. http://dx.doi.org/10.4028/www.scientific.net/msf.688.407.

Testo completo

Abstract (sommario):

The glassy alloy rods of Cu50Zr43Al7, (Cu50Zr43Al7)100-xYx(x=2,5) and (Cu50Zr43Al7)100-xAgx(x=6,7) with diameters of 3.0 mm were prepared by copper mold suction casting method. The influence of adding Ag and Y to Cu50Zr43Al7 metallic glass on glass formation ability (GFA) and thermal stability was studied by means of X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC). The results show that Ag and Y appropriate micro-addition enhance the glass formation ability and thermal stability of the Cu-Zr-Al metallic glass. The effect of Ag is better than that of Y. The addition of Ag causes a increase of the reduced glass transition temperature (Trg) of (Cu50Zr43Al7)100-xAgx alloy from 0.618 at 0 at.% Ag to 0.628 at 7 at.% Ag. The width of the supercooled liquid region of Cu43Zr43Al7Ag7 glassy alloy increases about 25K compared with that of Cu50Zr43Al7, and the γ value of Cu43Zr43Al7Ag7 reaches 0.433. The electrochemical corrosion behaviors of Cu50Zr43Al7, (Cu50Zr43Al7)100-xYx(x=2,5) and (Cu50Zr43Al7)100-xAgx(x=6,7) metallic glasses in 3.5% NaCl solution were investigated by potentiodynamic polarization method. It is found that corrosion resistance of all amorphous alloys is better than that of the corresponding crystalline alloys. The Ag and Y micro-addition improve corrosion resistance of Cu50Zr43Al7 metallic glass. The corrosion current density of Cu43Zr43Al7Ag7 metallic glass decreases 1~2 orders of magnitude compared with that of Cu50Zr43Al7.

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Men, H., S. J. Pang e T. Zhang. "Effect of Er doping on glass-forming ability of Co50Cr15Mo14C15B6 alloy". Journal of Materials Research 21, n. 4 (1 aprile 2006): 958–61. http://dx.doi.org/10.1557/jmr.2006.0109.

Testo completo

Abstract (sommario):

Bulk glass formation of the Co–Cr–Mo–C–B–Er alloy system was investigated in this paper. The Co50Cr15Mo14C15B6 (at.%) alloy could be cast into fully glassy rod with a diameter up to 2 mm. By adding 2 at.% Er to this alloy, the critical diameter for glass formation reached 10 mm. The excellent glass formability of the Er-doped alloy was mainly attributed to its relatively large reduced glass transition temperature of 0.61, near-eutectic composition, and the necessity of redistribution of the Er atoms for precipitation of crystalline Co6Mo6C phase in the undercooled liquid on cooling.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Wang, Shunbo, e Yu S. Tver’yanovich. "Relationship of Temperature Dependences of Microhardness and Enthalpy of Glass on the Example of Selenium". Физика и химия стекла 49, n. 4 (1 luglio 2023): 395–400. http://dx.doi.org/10.31857/s0132665123600012.

Testo completo

Abstract (sommario):

A model is proposed that makes it possible to calculate the temperature dependence of the microhardness of glass over the entire temperature range from the softening temperature to absolute zero. The calculation uses the temperature dependence of the glass enthalpy and the value of its microhardness at the glass transition temperature. The proposed model is tested on the example of glassy selenium. For this, the temperature dependence of the microhardness of selenium on the softening temperature up to 100 K, which is 50 K below its Debye temperature, is measured. Thus, a relationship is established between the strength and thermodynamic properties of glass.

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Loryuenyong, Vorrada, e Achanai Buasri. "Preparation of Luminescent Glass Aggregates from Soda-Lime Waste Glass". International Journal of Photoenergy 2021 (8 novembre 2021): 1–6. http://dx.doi.org/10.1155/2021/5951258.

Testo completo

Abstract (sommario):

This research studied the preparation of luminescent glass aggregates prepared from soda-lime waste glass and strontium aluminate-based phosphors. The properties of the samples were determined by means of X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), Archimedes’ method, and photoluminescence (PL) spectroscopy. It was found that the pore characteristics, density, and formation of crystallite phases in the glassy matrix depended on the phosphor content. The addition of fine phosphor powder tended to inhibit the glass crystallization and to reduce the apparent porosity of the aggregates. In general, the disadvantage of phosphors is their luminescent degradation under thermal attacks, which limits their use in applications involving high-temperature annealing. The phosphors, however, still had good luminescent properties and long-term stability with the sintering temperature as high as 750°C. The results indicated that the phosphors could be composited with glasses at high processing temperatures, enabling their widespread application.

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Shevchenko, V. V., e S. Yu Stoshkus. "Coloring glass blocks with thin glassy coatings". Glass and Ceramics 44, n. 5 (maggio 1987): 183–86. http://dx.doi.org/10.1007/bf00699384.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Boulon, G. "Luminescence in glassy and glass ceramic materials". Materials Chemistry and Physics 16, n. 3-4 (febbraio 1987): 301–47. http://dx.doi.org/10.1016/0254-0584(87)90104-0.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Lin, Chung Kwei, e Pee Yew Lee. "Consolidation of Mechanically Alloyed Cu-Zr-Ti Metallic Glass Powders". Key Engineering Materials 732 (marzo 2017): 5–10. http://dx.doi.org/10.4028/www.scientific.net/kem.732.5.

Testo completo

Abstract (sommario):

In the present study, Cu60Zr30Ti10 metallic glass powders were prepared by mechanical alloying of pure Cu, Zr, and Ti powder mixtures. Cu60Zr30Ti10 metallic glass composite powders were obtained after 5 h of milling as confirmed by X-ray diffraction and transmission electron microscopy. The metallic glass powders were found to exhibit a supercooled liquid region before crystallization. Cu60Zr30Ti10 bulk metallic glass were synthesized by vacuum hot pressing the as-milled Cu60Zr30Ti10 metallic glass powders at 723 K in the pressure range of 0.72 ~ 1.20 GPa. Cu60Zr30Ti10 BMG with nanocrystalline precipitates homogeneously embedded in a highly dense glassy matrix was successfully prepared under applied pressures. It was found that the pressure could enhance the thermal stability and prolong the existence of amorphous phase inside Cu60Zr30Ti10 powders.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Jin, H. J., e K. Lu. "An indirect approach to measure glass transition temperature in metallic glasses". International Journal of Materials Research 97, n. 4 (1 aprile 2006): 388–94. http://dx.doi.org/10.1515/ijmr-2006-0065.

Testo completo

Abstract (sommario):

Abstract Glass transition behavior of metallic glasses under some extraordinary conditions (such as under high pressures) remains unexplored. Conventional measurements of glass transition temperature, T g, are very difficult to perform under these extraordinary circumstances. In the present paper, we introduce an indirect approach to characterize glass transition, using enthalpy recovery experiments. With annealing deeply relaxed glassy samples and subsequent DSC measurements, a variation of enthalpy change upon heating with annealing temperature can be obtained. The variation of enthalpy change, a signature of glass transition, was found to correlate well with the directly measured DSC curves for the glass transition. This unique method was successfully applied in determining T g of several metallic glasses under hydrostatic high pressures and compression stresses.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "Glass"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili