scholarly journals Evaluation of Sinking-In and Cracking Behavior of Soda-Lime Glass under Varying Angle of Trigonal Pyramid Indenter

2016 ◽  
Vol 3 ◽  
Author(s):  
Satoshi Yoshida ◽  
Ken Wada ◽  
Takahiro Fujimura ◽  
Akihiro Yamada ◽  
Mitsuo Kato ◽  
...  
Author(s):  
Nitin Kumar Lautre ◽  
Apurbba Kumar Sharma ◽  
Shantanu Das ◽  
Pradeep Kumar

Processing of glass is indeed challenging owing to its chemical passivity; it is prone to cracking while processing through mechanical and thermal modes without appropriate strategies. Near-field microwave drilling is a thermal-ablation based material removal technique of generating high heat flux in the targeted area. Glasses tend to fail quite frequently during this processing owing to thermal stresses (shock). It was therefore important to develop suitable strategies to minimize cracking during this potentially pragmatic process for microdrilling. Accordingly, in the present work, an attempt was made to change the medium of the interface at the target drilling zone through application of seven different surface precursors to influence the local heat-flow characteristics. The cracking behavior of the soda lime glass during microwave drilling in a customized applicator under controlled power input (90–900 W) at 2.45 GHz was investigated. The heat was generated inside the applicator by creating a plasma sphere in the drilling zone through a metallic concentrator. The thermal shock on the glass specimen was found reduced by the combination of a good dielectric precursor and microwave concentration for hotspot formation, which in turn, reduces the cracking/crazing tendency. Trials were carried out while drilling holes on 1.2 mm thick glass plates at various duty cycles (DCs) to study the crack intensity and pattern. The near-field microwave drilling condition was also simulated to obtain the contours of the induced stresses. The results so obtained were compared with the cracking signatures of the experimental outputs; a good correlation could be obtained. It was found that both solid and liquid fluxes as precursor could be effective to control cracking during microwave drilling.


Author(s):  
Branimir Bajac ◽  
Jovana Stanojev ◽  
Slobodan Birgermajer ◽  
Milena Radojevic ◽  
Jovan Matovic

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 129
Author(s):  
Marcos Soldera ◽  
Sabri Alamri ◽  
Paul Alexander Sürmann ◽  
Tim Kunze ◽  
Andrés Fabián Lasagni

All-purpose glasses are common in many established and emerging industries, such as microelectronics, photovoltaics, optical components, and biomedical devices due to their outstanding combination of mechanical, optical, thermal, and chemical properties. Surface functionalization through nano/micropatterning can further enhance glasses’ surface properties, expanding their applicability into new fields. Although laser structuring methods have been successfully employed on many absorbing materials, the processability of transparent materials with visible laser radiation has not been intensively studied, especially for producing structures smaller than 10 µm. Here, interference-based optical setups are used to directly pattern soda lime substrates through non-lineal absorption with ps-pulsed laser radiation in the visible spectrum. Line- and dot-like patterns are fabricated with spatial periods between 2.3 and 9.0 µm and aspect ratios up to 0.29. Furthermore, laser-induced periodic surface structures (LIPSS) with a feature size of approximately 300 nm are visible within these microstructures. The textured surfaces show significantly modified properties. Namely, the treated surfaces have an increased hydrophilic behavior, even reaching a super-hydrophilic state for some cases. In addition, the micropatterns act as relief diffraction gratings, which split incident light into diffraction modes. The process parameters were optimized to produce high-quality textures with super-hydrophilic properties and diffraction efficiencies above 30%.


Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 488
Author(s):  
Oumaima Nasry ◽  
Abderrahim Samaouali ◽  
Sara Belarouf ◽  
Abdelkrim Moufakkir ◽  
Hanane Sghiouri El Idrissi ◽  
...  

This study aims to provide a thermophysical characterization of a new economical and green mortar. This material is characterized by partially replacing the cement with recycled soda lime glass. The cement was partially substituted (10, 20, 30, 40, 50 and 60% in weight) by glass powder with a water/cement ratio of 0.4. The glass powder and four of the seven samples were analyzed using a scanning electron microscope (SEM). The thermophysical properties, such as thermal conductivity and volumetric specific heat, were experimentally measured in both dry and wet (water saturated) states. These properties were determined as a function of the glass powder percentage by using a CT-Meter at different temperatures (20 °C, 30 °C, 40 °C and 50 °C) in a temperature-controlled box. The results show that the thermophysical parameters decreased linearly when 60% glass powder was added to cement mortar: 37% for thermal conductivity, 18% for volumetric specific heat and 22% for thermal diffusivity. The density of the mortar also decreased by about 11% in dry state and 5% in wet state. The use of waste glass powder as a cement replacement affects the thermophysical properties of cement mortar due to its porosity as compared with the control mortar. The results indicate that thermal conductivity and volumetric specific heat increases with temperature increase and/or the substitution rate decrease. Therefore, the addition of waste glass powder can significantly affect the thermophysical properties of ordinary cement mortar.


2020 ◽  
Author(s):  
Iskender Akkurt ◽  
Kadir Gunoglu ◽  
Recep Kurtuluş ◽  
Taner Kavas

Heritage ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 524-540
Author(s):  
Philippe Colomban ◽  
Gulsu Simsek Franci ◽  
Farahnaz Koleini

In the late 19th century, ancient tombs were discovered near the village of Vohemar at the northeastern point of Madagascar, and subsequent excavations during the French period (1896–1945) revealed the presence of a major necropolis active from ~13th to 18th centuries. Some artefacts (Chinese ceramic shards and glass trade beads) recovered from these excavations was sent to France and now in part belong to the collection of the Musée d’Histoire Naturelle, Nimes. Carnelian and glass trade beads were analyzed with a mobile Raman spectrometer, which identified different materials (soda-lime glass, quartz/moganite, carnelian/citrine, chalcedony) and coloring agents (Naples yellow, cassiterite, amber chromophore, transition metal ions, etc.). The results are compared with those obtained on beads excavated at different sites of Southern Africa and at Mayotte Island, and it appears that (most of) the beads come from southern Asia and Europe. The results confirmed the role that northern Madagascar played within the maritime networks of the Western Indian Ocean during the 15th–16th century.


2004 ◽  
Vol 836 ◽  
Author(s):  
Ki-Hyun Kim ◽  
Young-Gab Chun ◽  
Byung-Ok Park ◽  
Kyung-Hoon Yoon

ABSTRACTCIGS nanoparticles for the CIGS absorber layer have been synthesized by low temperature colloidal routes. The CIGS absorber layers for solar cells have been prepared by spray deposition of CIGS nanoparticle precursors (∼20 nm) in glove box under inert atmosphere. An automatic air atomizing nozzle spray system with computer controlled X-Y step motor system was used to spray. The nanoparticle precursor CIGS film was deposited onto molybdenum-coated soda-lime glass substrates (2.5 cm × 5.0 cm) heated to 160°C. The film thickness in the range of 2 μm ± 0.3 μm was attained by spraying of 3 mM colloidal over an area of 12.5 cm2. The coalescence between particles was observed in the CIGS absorber layer under post-treatment of over 550 °C. This is related to the reactive sintering among the nanoparticles to reduce surface energy of the particles. The CuxSe thin film, formed on Mo film by evaporation, improved adhesion between CIGS and Mo layers and enhanced the coalescence of the particles in the CIGS layer. These are closely related to the fluxing of Cu2Se phase which has relatively low melting temperature. The CdS buffer layer was deposited on the CIGS/Mo/soda-lime glass substrate by chemical bath deposition. The CIGS nanoparticles-based absorber layers were characterized by using energy dispersive spectroscopy (EDS), x-ray diffraction (XRD) and high-resolution scanning electron microscopy (HRSEM).


2005 ◽  
Vol 865 ◽  
Author(s):  
P. D. Paulson ◽  
S. H. Stephens ◽  
W. N. Shafarman

AbstractVariable angle spectroscopic ellipsometry has been used to characterize Cu(InGa)Se2 thin films as a function of relative Ga content and to study the effects of Cu off-stoichiometry. Uniform Cu(InGa)Se2 films were deposited on Mo-coated soda lime glass substrates by elemental evaporation with a wide range of relative Cu and Ga concentrations. Optical constants of Cu(InGa)Se2 were determined over the energy range of 0.75–C4.6 eV for films with 0 ≤ Ga/(In+Ga) ≤ 1 and used to determine electronic transition energies. Further, the changes in the optical constants and electronic transitions as a function of Cu off-stoichiometry were determined in Cu-In-Ga-Se films with Cu atomic concentration varying from 10 to 25 % and Ga/(In+Ga) = 0.3. Films with Cu in the range 16–24 % are expected to contain 2 phases so an effective medium approximation is used to model the data. This enables the relative volume fractions of the two phases, and hence composition, to be determined. Two distinctive features are observed in the optical spectra as the Cu concentration decreases. First, the fundamental bandgaps are shifted to higher energies. Second, the critical point features at higher energies become broader suggesting degradation of the crystalline quality of the material.


2014 ◽  
Vol 22 (13) ◽  
pp. 16493 ◽  
Author(s):  
Masaaki Sakakura ◽  
Kouhei Yoshimura ◽  
Torataro Kurita ◽  
Masahiro Shimizu ◽  
Yasuhiko Shimotsuma ◽  
...  

1994 ◽  
Vol 9 (2) ◽  
pp. 476-485 ◽  
Author(s):  
D.M. Kulawansa ◽  
L.C. Jensen ◽  
S.C. Langford ◽  
J.T. Dickinson ◽  
Yoshihisa Watanabe

We report scanning tunneling microscope images of gold-coated fracture surfaces of soda lime glass and fused silica in the mirror region. The scans show a variety of nanometer scale features that are attributed to fracture phenomena at this scale. We find considerable similarity to the structures observed in regions of extensive crack branching (e.g., “mist”). The density of these features increases as one progresses away from the crack origin toward the mirror-mist boundary. Comparisons are made between soda lime glass and fused silica, revealing differences in the local deformation behavior of these two materials. Self-similarity of the observed structures is probed by measurements of the fractal dimension, Df, of the surfaces created in soda lime glass near the mirror-mist boundary, where we observe 2.17 > Df > 2.40.


Sign in / Sign up

Export Citation Format

Share Document