Glass Layer Research Articles

Preparation and properties of SiC/SiC-SiYC with excellent water-oxygen corrosion resistance

In this study, the SiC/SiC-SiYC composites were fabricated via chemical vapor infiltration (CVI) combined with the reactive melt infiltration (RMI) process. The excellent infiltration of Si-Y alloy assisted in fabricating composites with a density of 2.94 g/cm3 and a porosity of only 2.0%. After 20 h of corrosion at 1300 °C in the water-oxygen environment, the generated oxide layer, consisting of a glass layer and a diffusion layer, effectively protected the composites, and the flexural strength retention is 114.2%. This study highlights the significant potential of Si-Y alloy as a modification phase that is resistant to water and oxygen. It also presents a novel approach for developing high-density ceramic matrix composites that are resistant to water-oxygen corrosion.

Impact Fracture Simulation of Laminated Glass Based on Thick Shell Elements and a Cohesive Zone Model.

Laminated glass is extensively used in automotive windshields, making it crucial to have a comprehensive understanding of its fracture mechanism to ensure driver and pedestrian safety in various windshield impact scenarios. Current research on the cohesive zone model of glass impact failure has encountered challenges related to accuracy and computational efficiency. This paper addresses these issues by utilizing the finite element software LS-DYNA, which integrates a cohesive zone model and thick shell (Tshell) elements to simulate and analyze the impact failure process of laminated glass. The combination of Tshell and cohesive elements was validated using a DCB example. Subsequently, the proposed method was applied to simulate the impact damage on an automobile's front windshield, providing valuable insights from the obtained results. Finally, the influence of curvature, the number of layers, and the thickness ratio of each layer were investigated, leading to some valuable conclusions. Firstly, an increase in the thickness of the upper glass layer correlates with a decrease in the peak acceleration of the dummy-head model due to the ductility of PVB material. Secondly, when a curvature exists, the arched configuration of the windshield promotes higher resistance against impact, consequently leading to increased peak acceleration.

Performance of LG window systems with different materials under extreme static loading

Laminated glass (LG) is created by bonding two or more glass layers together with one or more polymer interlayer(s). LG may significantly lower the risk of injury from broken glass because the polymeric interlayer retains the glass pieces, especially when subjected to explosive threats. Many interlayer materials have recently been used in LG panels, but the effects on the performance of glass thickness and type, interlayer thickness and type, and hybrid interlayers are not well known. In this work, we report on new implicit and explicit nonlinear finite element models for simulating pressurized water-chamber-like quasi-static tests. The numerical models were validated using 18 by 18 in. LG tests. This study shows that the resistance function of LG can be well predicted numerically and can be used as a tool to study the effects of various glass and interlayer types and configurations. Explicit solutions had a slightly greater resolution in predicting the fracture behavior and post-peak response and captured the distinct failure points of the inner and outer glass panes. Implicit calculations maintained high levels of accuracy and were orders of magnitude faster than the explicit simulations. Using the implicit method, a parametric study was conducted on 38 by 66 in. LG to determine the effects of glass and interlayer thickness, size, and layup configuration. The LG resistance function was improved within the pre-cracked stage by increasing interlayer thickness. Ionoplast SentryGlas® interlayers were shown to be the strongest of the three types considered. Additionally, unique hybrid interlayers were simulated and indicated that strength and bonding can be maximized using various hybrid configurations.

Photonic spin Hall effect-based ultra-sensitive refractive index sensor for haemoglobin sensing applications

A highly sensitive Photonic Spin Hall Effect (PSHE)-based layered sensor is proposed which detects changes in refractive index of biological sample. A simple and elegant design measures haemoglobin concentrations using Surface Plasmon Resonance (SPR) effect. It consists of a BK7 prism, a thin gold layer, an analyte layer of haemoglobin and BK7 glass as the substrate. The average angle sensitivity (SR) has been calculated and found to be 191°/RIU, 208°/RIU and 171°/RIU respectively for low, normal and high haemoglobin concentrations. The Figure of Merit (FOM) for the proposed structure is found to be 896RIU-1, 812RIU-1 and 3166RIU-1 respectively for low, normal and high concentrations of oxygenated haemoglobin.

Surface Activation of Calcium Zirconate-Calcium Stabilized Zirconia Eutectic Ceramics with Bioactive Wollastonite-Tricalcium Phosphate Coatings.

In this work, we have developed and characterized a ceramic composite based on a core of directionally solidified calcium zirconate-calcium stabilized zirconia (CZO-CSZ) eutectic composite coated with a bioactive glass-ceramic. The aim is to research new orthopedic implants as an alternative to conventional 3Y-TZP bioinert ceramics. The CZO-CSZ eutectic rods were grown from the melt of rods of CaO-ZrO2 in the eutectic composition using the laser floating zone technique (LFZ). The mechanical results indicated that directional eutectics prepared with this technique exhibited good mechanical strength and significant hardness and toughness. The LFZ technique was also used to melt the bioactive coating previously placed by dip coating on the CZO-CSZ rod surface. Depending on the thickness of the coating and the applied laser power, an alloying or coating process was achieved. In the first case, the coating was diluted with the surface of the eutectic cylinder, leading to the segregation of the calcium zirconate and zirconia phases and the formation of a bioactive phase embedding zirconia particles. In the second case, a layer of ceramic glass was formed, well attached to the eutectic cylinder. These layers were both studied from the microstructural and bioactivity points of view.

HfC[sbnd]HfO2[sbnd]SiO2 nanocomposite ceramic coating formed on TiAlNb medium-entropy alloy by LPDS: Microstructure evolution and ablation behavior

HfCHfO2SiO2 nanocomposite ceramic coating was prepared on the TiAlNb medium-entropy alloy by a novel one-step liquid plasma-assisted particle deposition sintering (LPDS) method to improve the ablation resistance. Meanwhile, PEO coatings were prepared as a comparison at different voltages (400 V, 450 V, 500 V). When the PEO coating fabricated at 500 V was ablated for 360 s, the peeling area was the largest at 41.05 %, which was 2.3 times larger than the PEO coating (400 V, 18.03 %). However, the HfCHfO2SiO2 nanocomposite coating exhibits no surface peeling. The surface particles of the coating were sintered together, reducing the presence of pores and enhancing the structure density. Additionally, a large amount of HfO2 and stable HfSiO4 particles were embedded in the amorphous SiO2 layer, which improved the melting point and stability of the glass layer while reducing oxygen permeability. The formed HfSiO4 after ablation acted as “nails”, effectively suppressing the generation of cracks.

Thermal performance of an innovative double-skin ventilated façade with multistep-encapsulated PCM integration

The simultaneous occurrence of nighttime insulation requirements and daytime overheating risks in a single day is a concern of buildings that is often overlooked. This study introduces a novel approach utilizing a dual-phase change materials (DPCM) layer in a double-skin ventilated glazing façade (DSPVGF) to store and release energy through photothermal conversion. This technology facilitates heat removal during the day via a ventilation layer and the reduces long-wave radiation through a vacuum glass layer. The thermal performance of DSPVGF is evaluated under a temperate continental climate characterized by significant diurnal temperature variations. Emphasis is placed on considering the net solar energy gain of DSPVGF. The results demonstrate that DSPVGF outperforms ventilated façades utilizing air or PCM, exhibiting the lowest heat transfer rate of 30.03 W. Optimal DSPVGF configurations for climates with substantial temperature fluctuations are identified, including a DPCM melting temperature of 28 °C and 16 °C, a thickness of 36 mm, and multistep placement by turn according to a height-to-width ratio of 200D. Daytime ventilation with a flow velocity of 1.09 m·s−1 is confirmed as the most effective passive cooling strategy.

Zero-Mode Waveguide Nanowells for Single-Molecule Detection in Living Cells.

Single-molecule fluorescence imaging experiments generally require sub-nanomolar protein concentrations to isolate single protein molecules, which makes such experiments challenging in live cells due to high intracellular protein concentrations. Here, we show that single-molecule observations can be achieved in live cells through a drastic reduction in the observation volume using overmilled zero-mode waveguides (ZMWs- subwavelength-size holes in a metal film). Overmilling of the ZMW in a palladium film creates a nanowell of tunable size in the glass layer below the aperture, which cells can penetrate. We present a thorough theoretical and experimental characterization of the optical properties of these nanowells over a wide range of ZMW diameters and overmilling depths, showing an excellent signal confinement and a 5-fold fluorescence enhancement of fluorescent molecules inside nanowells. ZMW nanowells facilitate live-cell imaging as cells form stable protrusions into the nanowells. Importantly, the nanowells greatly reduce the cytoplasmic background fluorescence, enabling the detection of individual membrane-bound fluorophores in the presence of high cytoplasmic expression levels, which could not be achieved with TIRF microscopy. Zero-mode waveguide nanowells thus provide great potential to study individual proteins in living cells.

Design and analysis of an optical planar waveguide using Invar as core and silicon nitride as cladding layer to control birefringence

Abstract The main problem with optical planar waveguide is thermal stress which arises when layers inside the planar waveguide get fused together with different coefficient of thermal expansion (CTE) and due to variation in thermal properties, the problem of thermally induced strain and birefringence occurs inside the waveguide glass layer. In proposed work, the mathematical analysis of thermal induced stress and the thermal strain in waveguide glass layer is calculated. ‘C’ software is used for analysis of an optical planar waveguide to calculate the thermal stress. By using material properties of Invar (64 % iron-36 % nickel alloy) and silicon nitride (Si3N4) an optical planar waveguide is designed. Here when silicon nitride (Si3N4) is used as a cladding layer and Invar (64 % iron-36 % nickel alloy) as a core layer in an optical planar waveguide, the problem of birefringence get eradicated as zero thermal stress was achieved.

The effect of plasma treatment on the mode II interlaminar fracture toughness of Glass/Epoxy laminates

Despite the key advantages of fiber-reinforced polymer composites, such as high specific strength and stiffness, these materials are characterized by low interlaminar fracture toughness. This study aims to investigate the effect of dielectric-barrier discharge (DBD) plasma treatment of glass fibers on the mode II interlaminar fracture toughness (GIIC) of glass/epoxy composite laminates. To this aim, first, end-notched bending (ENF) specimens were fabricated using the vacuum infusion process. During the laminating process of the specimens, the two adjacent glass layers at the top and bottom faces of the pre-delamination were exposed to an atmospheric DBD plasma for different exposure times (R: reference specimens without plasma treatment, PT2: specimens with two rounds of treatment, and PT5: specimens with five rounds of treatment). Afterward, the ENF specimens were subjected to three-point bending loading according to ASTM D7905 standard. The results showed an increase of ∼ 51% and ∼ 56% in GIIC for PT2 and PT5 specimens compared to the reference specimens (R), respectively. The Fourier-transform infrared spectroscopy (FTIR) analysis indicated that the plasma treatment did not generate new functional groups at the surface of glass fibers; therefore, there was no increase in the chemical bonding strength of the fibers to the resin. However, scanning electron microscopy (SEM) revealed that the plasma treatment increased the adhesion of the glass fibers to epoxy by removing sizing of the glass fibers and increasing the surface roughness of the fibers. The results of the present study showed that the plasma treatment can be considered as a cheap, easy-to-use, cost effective and scalable method for toughening laminated composites instead of the costly and difficult methods such as electrospun nanofibers and z-pinning.

Assessment of Photocatalytic Nano-TiO2 Mortars’ Behavior When Exposed to Simulated Indoor Conditions of Glazed Buildings

The application of nano-TiO2 as a photocatalytic agent in buildings’ internal surfaces has recently attracted attention to mitigate microorganism growth, soiling, and contamination in indoor environments. This work aimed at comparing the Rhodamine B (RhB) dye degradation efficiency of three different mortar compositions subjected to simulated internal radiation, in which nano-TiO2 (10 wt% of binder mass) was dispersed by ultrasonic and mechanical methods. Mortar specimens were produced with white Portland cement, hydrated lime, sand, and water in different volume proportions of 1:1:6 (cement:lime:sand), 1:3 (cement:sand), and 1:4 (cement:sand). The first stage of the research evaluated samples exposed to the natural outdoor environment and proved the efficiency of specimens’ photoactivity when covered by a glass layer. The second and principal phase of the study simulated indoor conditions in glazed buildings through artificial weathering in which the composition of 1:1:6 was mechanically dispersed and exhibited the highest global color change (ΔE) values for RhB staining. The main finding of the study was that the mortars exposed to simulated indoor conditions presented high ΔE grades, classified as easily perceived by the human eye. This demonstrates the photocatalytic efficiency in an internal building environment that receives radiation through a glass surface.

Effect of polyurethane matrix and steel fiber in combination with glass fiber or basalt fiber on the properties of hybrid composite laminates

Abstract Polyurethane is a versatile polymer with a high degree of toughness and ductility used in a wide variety of applications. In this study, two-part thermoset polyurethane was used as a matrix material to prepare hybrid and non-hybrid composites. Hybrid laminates were prepared by combining either glass fiber or basalt fibers with steel fibers. The mechanical properties of prepared composite specimens were characterized and scanning electron microscope (SEM) observation was performed around the fracture region of the tested specimens. The results revealed a significant increment in tensile strength, and flexural strength in BS1-PU (8 layers of basalt-1 layer of steel) hybrid laminate by 357.74 % and 64.59 %, respectively, compared to steel fibers reinforced polyurethane composites. Furthermore, GS4-PU hybrid composite (5 layers of glass-4 layers of steel) achieved an improvement in tensile strain by 12.07 %, flexural strain by 25.32 %, and absorbed energy by 18.21 %, compared to glass fibers reinforced polyurethane composite. Moreover, the SEM observations revealed that the replacement of some basalt and glass layers with steel layers leads to a positive hybridization effect of the overall produced hybrid composites.

Oxygen blocking enhancement of HfB2-SiC coating using HfB2-HfSi2 alloyed composite powders by self-propagating high-temperature synthesis

To suppress the oxidation loosening of HfB2-SiC coating, the HfB2 was alloyed with HfSi2 in the form of composite powders through self-propagating high-temperature synthesis (SHS) technique, which was then used to prepare HfB2-HfSi2-SiC coatings. Compared to the 60HfB2-SiC coating, the 60(HfB2-HfSi2)SHS-SiC coating exhibited lower oxidation activity and better inert oxygen blocking at 1700 °C. The addition of HfSi2 promoted the homogenization of the Hf-oxides distribution on the glass layer and the formation of the protective phase HfSiO4, further inhibiting oxygen diffusion. The 60(80HfB2-20HfSi2)SHS-SiC coating exhibited optimal oxygen blocking protection after oxidation at 1700 °C, with 87.96% and 92.33% reductions in oxygen permeability and carbon loss rate, respectively.

ANSYS investigation of solar photovoltaic temperature distribution for improved efficiency

<p>A computational analysis of the influence of varying solar module material properties on operating temperature is presented and related to electrical conversion efficiency through the devised method. By varying the properties of density, specific heat capacity, and isotropic thermal conductivity for each material that comprises a solar module, density, and specific heat capacity were found to have the greatest influence on decreasing the operating temperature when increased by a factor of 50% for the glass layer, resulting in a decrease in temperature of 5.33 °C. Utilizing the devised method, which is based on the work of Palumbo, this temperature decrease was correlated to an electrical efficiency increase of 3.08%.</p>

Effects of Different Primers on the Bond Strength to Properly and Excessively Etched Ceramic-coated Zirconia.

To determine the effects of various primers on the immediate and long-term bond strength of ceramic-coated ultratranslucent zirconia that is properly or excessively etched. Ceramic-coated zirconia plates were etched with 9.5% hydrofluoric acid (HF) for 2 or 5 minutes, after which the surface morphology and elemental composition were examined. The etched specimens were treated with different primers including methacryloyloxydecyl dihydrogen phosphate (MDP)-only containing primer, silane-only containing primer, MDP and silane-containing ceramic primer as well as MDP and silane-containing adhesive system. For surface contact angle and shear bond strength (SBS) data, the difference between groups was evaluated by one-way analysis of variance (ANOVA) and three-way ANOVA factorial analysis, respectively. The statistical significance level of 0.05 was set and the Tukey test and the Dunnett-T3 test were used for post-hoc multiple comparisons. Excessive etching (9.5% HF for 5 minutes) led to overconsumption of the glass layer and exposure of zirconia substrate compared to proper etching (9.5% HF for 2 minutes). Among different primers, the surface contact angle of the silane-only containing primer group was the lowest. The silane-only containing primer and MDP and silane-containing ceramic primer produced higher shear bond strength of properly and excessively etched ceramic-coated zirconia, respectively, both before and after thermal aging. The silane-only containing primer and MDP and silane-containing primer can obtain better immediate and long-term shear bond strength for properly and excessively etched ceramic-coated zirconia, respectively.

Properties of Multi-Component Fire Extinguishing Systems Based on Light Bulk Materials

To extinguish flammable liquids, it is suggested to use a multi-component fire extinguishing system consisting of two layers. The first layer is designed to ensure the buoyancy of the fire extinguishing system. It is suggested to use crushed foam glass as the material of this layer. As the material of the upper layer, it is suggested to use light dispersed materials with increased thermal insulation properties. As such materials, the use of exfoliated perlite and vermiculite is justified. To increase the insulating and cooling properties of the fire extinguishing system, wetting of the upper layer with water is used. Bulk density, buoyancy in heptane and moisture retention of crushed foam glass, expanded perlite and vermiculite were experimentally determined. The insulating properties of binary layers of foam glass + perlite and foam glass + vermiculite were studied. The heights of the layers of dry and wet bulk materials necessary for extinguishing heptane were determined experimentally. A conclusion was made about the advantages of the proposed fire extinguishing system based on light bulk materials compared to the existing fire extinguishing means.

Relationship Between Properties of Floating Systems and Flammable Liquids in the Stopping Their Burning Technology

The contributions balance of isolation and cooling effects relative to the liquids surface to slow down their evaporation and to achieve safe vapor concentrations is determined. The influence of liquids characteristic temperatures and their water solubility on this process is considered. It is proven that the long-term effect of such means is provided by systems based on closed-pore floating solid materials (for example, foam glass). It is proposed to increase the foam glass low isolation and cooling capacity either by coating it with an inorganic gel or by wetting it with water. Smaller evaporation retardation coefficients by gel were obtained for liquids with the higher water solubility. A 5–6 times greater cooling capacity of the wet foam glass than dry foam glass was obtained for both polar and non-polar liquids. A smaller cooling effect is observed for liquids with a higher vaporization heat and is similar for both the use of the dry and wet foam glass. It was found that for low-boiling non-polar liquids, the evaporation slowing down is more effectively achieved by using isolation effects, and for high-boiling polar and non-polar liquids - by using cooling effects. It is proved that the fire extinguishing effect by applying the foam glass layer on the flammable liquid surface occurs in a similar way for liquids with close equivalent cluster lengths and not flash temperatures.

Piecewise power law approximation of the interlayer relaxation curve for the long term viscoelastic fractional modeling of laminated glass

Laminated glass is composed of glass layers coupled by thin polymeric films which, being highly viscoelastic, influence the bending response over time. Here, an approximation of the polymer relaxation curve is proposed by means of continuously-connected power law branches. In the bi-logarithmic stress-time plane, this corresponds to a piecewise trilinear path, which well reproduces the experimental tests on most commercial polymers. A power law is naturally suited to be modeled via fractional calculus, as the Boltzmann convolution integral coincides with the definition of fractional derivative. However, the piecewise characterization through multiple power laws requires to properly extend the Grünwald–Letnikov integration scheme for fractional differential equations. For the paradigmatic case of a simply supported three-layer laminated beam, numerical results show an excellent correspondence with experiments under long duration loads. The comparison with the classic Prony series approach highlights, on the one hand, how calibration of material parameters is simplified; on the other hand, how the fractional approach is computationally more efficient and stable, even when the integration time step is wide enough to follow long term phenomena.

The role of tin and iron in the production of Spanish copper red glass from the 19th to the 20th century

Little is known about the materials used in the manufacture of red window glass in the 19th and the first decade of the 20th century. Here, we have studied fragments from eight Spanish glasses from the 19th and 20th centuries. The red glasses consist of a single layer of red glass on a colourless glass substrate. The chemical composition, oxidation state, nature of colourants and crystalline precipitates were determined by a selection of microanalytical techniques. In the study, we have found that the red colour of the glass is due to the presence of Cu0 nanoparticles, the red glass layer has lower calcium content than the substrate glasses, which we found favours copper being present in the glass predominantly in Cu+. They also contain tin and iron while lead, described in historical and modern documentation, was absent. Tin must have been added to the glass as a Sn2+ compound and acted as a reducing agent for copper. Iron is also a well-known reducing agent, but does not act as such in the red glasses studied here. However, it may have facilitated the reduction of copper to Cu0 by promoting its incorporation into the glass as Cu+ rather than Cu2+.

Antioxidant performance and oxidation mechanism of a liquid silicon infiltration (LSI) SiC–Si coating at an ultra-high temperature of 1873 K

A novel SiC–Si coating with a high amount of net-like distributed Si was fabricated on the graphite substrate by liquid silicon infiltration (LSI) method to improve the oxidation-resistant performance. The mass gain of this LSI coating after 300 h oxidation at 1873 K was only 3.018%, suggesting an excellent static antioxidant property at 1873 K. The detailed oxidation mechanism of this LSI coating was explored in this work. It was found that the high amount of Si with the net-like distribution in this LSI coating promoted the passivation growth of SiO2 glass layer and prevented the SiO2 glass from crystallizing into cristobalite. In addition, the Si in this coating retarded the active oxidation and enhanced the coating stability. In contrast, the infiltration (VSI) SiC–Si coating presented an apparent mass loss, and the pack cementation (PC) SiC coating showed the catastrophic failure. The oxidation mechanisms of these two coatings were also discussed against the backdrop of the LSI coating with high antioxidant performance.