Glass Powder Particles Research Articles

Hollow cylindrical three-dimensional nonlinear photonic crystal for annular beam generation

We present a hollow cylindrical three-dimensional nonlinear photonic crystal for annular beam shaping. By inducing a modification with the near-infrared femtosecond laser inside lithium niobate, we experimentally achieve second-order nonlinear optical coefficient modulation in three dimensions. The center dark spot ratio of the generated annular beam can be adjusted by varying the hollow ratio of the cylindrical structure. To demonstrate the controlled linear variation of the annular distribution, we generate annular beams with center dark spot ratios ranging from 0 to 0.7. Furthermore, we illustrate the feasibility of the generated annular beam in optical trapping by manipulating glass powder particles with diameters of 4–10 μm in water. Our hollow cylindrical structure owns effective control of beam dark spot ratio, while providing a tool for generating annular beam.

Chemical strengthening of glass powder particles

It is well known that chemical strengthening of glass brings the benefit of increased fracture strength. Despite extensive research on processing and mechanics at the macroscale, the effectiveness of chemical strengthening on glass elements with all three dimensions in the micrometer regime remains largely unexplored. Here, we develop a novel process for chemical strengthening of micrometer-sized spherical glass powder particles and study the fracture behavior of these particles with in-situ particle compression tests inside a scanning electron microscope. Cross-sectional microscopy and energy dispersive spectroscopy measurements confirm ion exchange and show an increase in diffusion depth with an increase in processing time and temperature. We report a higher fracture strength for chemically strengthened powder particles compared with the as-received ones. We show that the increase in fracture strength is associated to the compressive residual stress resulting from ion exchange during chemical strengthening.

The Influence of Excitation Method on the Strength of Glass Powder High-Strength Cementitious Materials

Recycling economy and the re-utilization of solid waste have become important parts of sustainable development strategy. To improve the utilization rate of waste glass, glass powder high-strength cementitious material (GHSC) was prepared by replacing part of the cement in the cementitious material with ground waste glass powder. Firstly, the effect of glass powder particle size on the flexural and compressive strength of GHSC was investigated by the gray correlation method, and the optimal grinding time was obtained. Additionally, the effect of the magnitude of steam curing temperature and the length of steam curing time on the compressive strength and flexural strength of GHSC was investigated, and the mechanism of the effect of the curing regime on the strength was explored by examination of the microstructure. Finally, to simplify the curing process of GHSC, the effects of Ca(OH)2 and Na2SO4 as excitation agents on the compressive strength and flexural strength of GHSC at different dosing levels were compared. The results showed that glass powder with a particle size of less than 20 μm would improve the compressive strength and flexural strength of the specimen. Steam curing can significantly improve the flexural strength and compressive strength of GHSC specimens. At a steam curing temperature of 90 °C for a duration of three days, the compressive strength and flexural strength of GHSC increased by 76.7% and 98.2%, respectively, compared with the standard curing specimens. Ca(OH)2 and Na2SO4 as excitation agents significantly enhanced the compressive and flexural strengths of GHSC under standard curing conditions.

Mechanical strength and microstructure of ultra‐high‐performance cementitious composite with glass powder substituted cement/silica fume

AbstractUltra‐high‐performance cementitious composite (UHPCC) incurs higher economic costs and resource wastage due to its high cement/silica fume (SF) content. The paper aims to achieve sustainability and environmental friendliness of UHPCC by substituting cement/SF with glass powder (GP). The influence of various GP particle sizes and substitution levels on the mechanical properties of UHPCC was investigated. X‐ray diffraction and scanning electron microscopy were employed to analyze the impact of GP on the hydration process of UHPCC from a microscopic perspective. In addition, the internal damage pattern of GP‐UHPCC was simulated by the RFPA3D program. The results show that the addition of GP could achieve superior fluidity than GP‐0. Compared to conventional UHPCC, GP‐20 exhibits improved strength, initial flexural toughness, and residual flexural toughness. Furthermore, finer GP particle sizes contribute to enhanced matrix strength and flexural energy absorption capacity to some extent. Additionally, the incorporation of 5%–20% GP leads to an increase in the characteristic peaks of hydrated lime and C‐S‐H gel, which are beneficial to improving the internal microstructure of the matrix. Based on the RFPA3D program, the crack area, principal stress distribution, and acoustic emission energy of specimens with 15%–25% GP substitution levels were significantly higher than those of specimens with low substitution levels (0%–10%). Generally speaking, a GP substitution level of 15%–25% is found the most effective range for improving strength, and toughness behavior in this study.

Laser powder bed fusion spatters of Zr-Cu-Al-Nb metallic glass

Understanding the morphology, composition and structural changes experienced by metallic glass powder particles upon laser powder bed fusion (LPBF) is the first step towards evaluating the impact of spatter generation on part quality and on feedstock degradation. This study presents the characterization of Zr-Cu-Al-Nb spatter particles by means of scanning and transmission electron microscopy with automated crystallographic orientation mapping and energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. The powder exposed to the LPBF environment exhibits an average surface composition similar to the original feedstock, but with a rougher morphology. The typical spatter encountered in the remaining lack-of-fusion is a vapour-entrained particle, which probably underwent partial melting leading to the formation of α-Zr(O) dendrites, and “big-cube” Cu2Zr4O nanocrystals in its heat affected zone. In the present work, spatter characteristics are discussed considering glass properties and their connection to lack-of-fusion defects is addressed.

Experimental Study of Sulfate Erosion Resistance of Cementitious Sand with Waste Glass Powder

In order to save natural resources and protect the natural environment, the relevant performance of waste glass powder as a building material must be enhanced. In general, volcanic ash activity is enhanced through grinding the glass powder particles to a specific degree of fineness, thereby improving the overall strength of cementitious sand. Our current need is to study the effects of replacing standard sand with glass powder of varying particle size and dosage range on its resistance to sulfate erosion as well as the corresponding mechanisms. To further examine the durability properties of glass powder cementitious sand, this study uses glass powder of 100–200 mesh and 200–500 mesh to create cementitious sand samples, replacing 10% and 15% of standard sand with equal volume. After curing for 28 days in a standard curing room, the samples are submerged in tap water and a 5% concentration of sodium sulfate solution for 30, 60, 90, 120, and 150 days. Subsequently, the mass loss rate, flexural strength, and compressive strength are measured to reflect the sulfate erosion resistance of the cementitious sand samples containing glass powder. The findings indicate that the flexural and compressive strengths of cementitious sand with waste glass powder experience a swift decline in strength during the pre-erosion stage and a slow decline or even an increase in strength during the post-erosion stage as erosion age progresses. As the glass powder dosage increases, there is a noticeable decrease in the flexural and compressive strengths, in which the doping of 200–500 mesh doped with 15% of glass powder has the worst effect on the resistance to sulfate erosion. As the particle size increases, both flexural and compressive strengths significantly improve, suggesting that sulfate erosion properties are gradually enhanced. The primary reason for this phenomenon is that when glass powder substitutes fine aggregate, the activity develops more slowly in the initial stage, primarily filling the pores and cracks. However, the activity increases rapidly later, more fully integrating with the cement mortar in sodium hydroxide’s hydration product to create dense hydrated calcium silicate crystals. This enhances the overall strength of the sample, filling the pore structure within the system, and is more conducive to resisting the erosion effect of sulfate ions on the sample.

State of the Art on Waste Glass Powder as Supplementary Cementitious Material

As a new type of high-performance concrete material, glass powder (GP) concrete is beneficial to the environment and concrete performance. However, the specific application method still needs to be studied. This paper introduces the structure theory of glass and the mechanism by which glass powder affects concrete. Through experiments, the effects of glass powder particle size, content, alkali content, and other factors on alkali-silica reaction (ASR) expansion, mechanical properties, and durability of concrete are compared. It is proven that glass powder can be used as a gel material in concrete. The existing problems in the research are summarized, and the latest research perspectives and methods are suggested.

Preparation, aging behavior and interface bonding of cordierite glass-ceramics as veneer porcelain for Si3N4 ceramics

In this work, aiming at developing veneer porcelain for Si3N4 dental ceramics, the cordierite glass-ceramics were prepared via the sintering method and the effects of glass powder particle size and accelerated aging time on the structure and properties of cordierite glass-ceramics were investigated. With the milling time extension, the glass powder particle size decreases and becomes more uniform, the sintering property, bending strength and fracture toughness increase and then decrease. The cordierite glass-ceramics prepared from glass powder with ball milling time of 10 h exhibit the optimum performance which meets the standard requirements for dental ceramics. Accelerated aging test was conducted in distilled water at 134 °C and 2 atm. After accelerated aging for 10 h, the performance of the samples still can meet the standard requirements, suggesting good stability and anti-aging properties. Effects of HF acid etching and oxidation treatment of Si3N4 ceramics on the microstructure, bonding strength and failure mechanism of the cordierite glass-ceramics/Si3N4 ceramics interface were assessed. HF acid etching can effectively improve the surface roughness of Si3N4 ceramics, and the interface exhibits a mixed failure mode with a bonding strength of 8.49 MPa.

Foam glass production from waste bottle glass using silicon cutting waste of loose abrasive slurry sawing as foaming agent

This study created foam glass from waste bottle glass employing silicon cutting waste (SCW) of loose abrasive slurry sawing as the foaming agent. The influence of affecting parameters, namely sintering temperature, glass powder particle size, SCW dosage, heating rate, holding time, were investigated. The produced foam glass was characterized to examine its microstructure, bulk density, compressive strength, porosity, and thermal conductivity, and was compared with that produced using silicon carbide (SiC) reagent as the foaming agent. The results indicated that under the optimal conditions of sintering temperature of 775 °C, glass powder particle size of 0.15 mm, SCW dosage of 1 wt% (the D50 of SiC in SCW was ca. 10 μm), heating rate of 10 °C/min, and holding time of 30 min, the produced foam glass had a compressive strength of 4.1 MPa, bulk density of 0.56 g/cm3, porosity of 78%, and thermal conductivity of 0.16 W/m·k; these properties meet with standards for thermal insulation materials. In contrast, using SiC reagent with a D50 of ca. 22 μm revealed 900 °C as the optimal sintering temperature, which yielded foam glass having a compressive strength of 5.4 MPa, bulk density of 0.67 g/cm3, porosity of 73%, and thermal conductivity of 0.2 W/m·k. By using SCW as the foaming agent, foam glass is able to be produced under comparatively low temperature and has favorable properties. In addition, the simultaneous waste valorization of waste bottle glass and SCW can be achieved.

Effect of glass powder on the mechanical and drying shrinkage of glass-fiber-reinforced cementitious composites

Ordinary Portland concrete (OPC) is characterized by low tensile strength and low toughness. These properties can be improved by adding glass fiber (GF). However, the alkaline environment of the pore solutions adversely affects the durability of GF. First, the effect of GF addition on the mechanical properties and fluidity of cement mortar was investigated. It was found that the fluidity decreased, and the flexural strength increased with an increase in the GF content. The incorporation of GF had little effect on the compressive strength of mortar. The optimal volume dosage of GF was 2 %. Then, Experiments were conducted to study the effects of glass powder (GP) characterized by different particle sizes and dosages on the fluidity, mechanical properties, and strength activity index (SAI) of glass-fiber-reinforced cementitious composites (GFRC). The results revealed that the fluidity, flexural strength, and compressive strength of GFRC containing GP increased with a decrease in the GP particle size. The flexural and compressive strength of GFRC first increased and then decreased with an increase in the GP content. The SAIs values of all GFRC specimens were more than 75 %, except GPI-25. Finally, the effect of the GPIV (GP of the optimal particle sizes) content on the drying shrinkage and pore structure of GFRC was studied. It was observed that the addition of GP into GFRC resulted in a reduction in the drying shrinkage, and the drying shrinkage of GFRC decreased with an increase in the GPIV content. The pore volume (0.5–50 nm) of GFRC decreased with an increase in the GPIV content. GP in GFRC consumed calcium hydroxide (CH) to produce calcium silicate gel. This helped reduce the extent of corrosion of GF by CH. Waste glass is processed into GP and added into mortar or concrete to replace parts of cement to reduce cement consumption and carbon dioxide emission. This helps protect the environment. GP is a promising agent for the fabrication of glass-fiber-reinforced cementitious composites.

INFLUENCE OF LIQUID FOAMING AGENT DISTRIBUTION ON THE FORMATION OF FOAM GLASS POROUS STRUCTURE

It was shown that the use of liquid-phase foaming agents is promising for the synthesis of foam glass. The dynamics of the change in the glass particles size in the process of batch obtaining was studied. It was shown that additional grinding of glass powder particles occurs during the mixing process. The influence of the time of the batch mixing on the structure of the foam glass was investigated. It was shown that the density of the obtained foam glass is directly proportional to the batch mixing duration. Changes in the structure of the material associated with the processes of distribution of a liquid foaming mixture on glass powder particles during mixing and subsequent changes in the dynamics of the glycerol thermal destruction processes were described.

Piezoresistive Sensor Based on Micrographite-Glass Thick Films.

A new Pb-free glass containing several oxides (Bi2O3, B2O3, SiO2, Al2O3 and ZnO) with sintering temperature reduced down to 600 °C has been developed for applications in a piezoresistive pressure sensor. Using this low sintering temperature glass, it was possible to fabricate micrographite-based pastes and piezoresistive films without losses of graphitic material during the sintering. Good adherence of the films onto alumina substrates was observed and attributed in part to the reactions of ZnO and Bi2O3 with alumina substrates. Piezoresistive films with uniformly distributed micrographite particles were produced using sodium carboxymethyl cellulose (NaCMC) in aqueous solutions during the preparation of pastes. NaCMC plays a decisive role in interactions between micrographite particles and glassy matrix, providing good wettability of glass powder particles and homogeneous distribution of MG particles in the pastes. Finally, excellent repeatability of the sensor response to the applied deformations was verified in cycling experiments when the sample was submitted to 1000 load/release cycles. These results demonstrated very high stability of the sensor response (within ±1%), and also evidenced high stability of the film under the cyclic strain loads and good film adherence to the substrate.

Effect the Ratio and Particle Size of Glass Powder from Fluorescent Tubes Waste on Electrical Properties of PVA-Glass Composites

The polymer composites used in the present study were made of polyvinyl alcohol (PVA) as a matrix and glass powder as a filler. The glass powder was obtained from fluorescent tubes waste. The solution casting method was used to fabricate PVA/glass powder composite. Three groups of samples were prepared. The first was prepared by using PVA with the addition of glass powder (sieved less than 20 μm) in proportions 10, 20, 30, 40, and 50 %. The second: the mixing ratios of PVA and glass powder were 80% and 20%, respectively. The third: The mixing ratios of PVA and glass powder were 60% and 40%, respectively. In Both previous groups, the added glass powder used was sieved with sizes less than 20, 45, 105, and 125 μm. For all samples, the following properties were measured at room temperature: DC electrical conductivity, dielectric constant, electrical conductivity, and dissipation factor. The last three properties were measured with a range of frequencies from 1kHz to 5MHz. DC conductivity increases with increasing of glass powder. It was found that the highest conductivity values are for samples composed of glass powder with a particle size of less than 45 μm for both ratios of glass 20% and 40%. It is also noticed that within most frequencies, the sample with 30% glass has the largest dissipation factor. At 20% filler of glass powder, it is noted that the highest values of the dielectric constant are for samples composed of glass powder with a particle size of less than 45 μm and 125 μm. Below 1 MHz, the effect of glass powder particle size on the AC conductivity is minimal. It is found that the samples containing glass powder (less than 125 μm and 105 μm), have similar and lowest dissipation factor. At 40% filler of glass powder, it is noted that the lowest values of the dielectric constant are for samples composed of glass powder with a particle size little than 105 μm.

Waste press mud in enhancing the performance of glass powder blended cement

Due to the significant environmental damages caused by cement production, the use of blended cement has gained greater attention. This paper explores the novel use of solid waste from the sugar industry namely press mud (PM) and waste glass powder (GP) as cement replacement in ternary blended cement. The ternary blended cement consists of 20% GP and the influence of PM at various cement replacement levels between 5 and 20% was investigated. The fresh, strength, sorption, morphological, and thermogravimetric characteristics of the ternary blended cements were evaluated. The results showed that the incorporation of 10% and 15% of PM could improve the consistency, early and later age strengths, exhibit similar flexural strength and reduce the sorptivity of the GP binary cement mortar. The morphologies were also observed to have improved by reducing of voids, facilitating reaction of GP particles, and contributing additional hydration products. This was confirmed by thermogravimetric analysis results, whereby more hydration products were found in cement-GP-PM ternary cement pastes. In overall, the suitable integration of PM could improve the properties of ternary blended cement containing GP while reducing the usage of cement.

Study on the Effect and Mechanism of Alkali–Silica Reaction Expansion in Glass Concrete

The suppression of ASR expansion hazards of glass concrete has always been a key and hot issue in the research of glass concrete. According to the ASTM C1260-14 fast mortar rod method, glass sand and glass powder act as fine aggregate and auxiliary cementing material, respectively. The changes in expansion rate with different amounts of glass sand content and different particle sizes of glass powder in mortar rods were compared, and the effects of glass sand content and the glass powder particle size on the expansion of ASR were analyzed. SEM was used to compare and analyze the microstructure of mortar rods to explore the mechanism of ASR expansion of glass concrete, and the results showed that the addition of glass powder had a certain inhibitory effect on ASR expansion. The larger the particle size of glass powder was, the better the inhibition effect on ASR expansion and the longer its duration. Compared with the three groups of experiments of 0–13 μm, 13–38 μm, and 38–75 μm, it was found that the influence of the glass powder particle size on the expansion of ASR was weaker than that of dosage. The inhibitory effect of glass powder on ASR expansion is related to the fact that glass powder is more involved in pozzolanic reaction in the early hydration process.

A novel dental re-mineralizing blend of hydroxyethyl-cellulose and cellulose nanofibers oral film loaded with nepheline apatite glass: Preparation, characterization and in vitro evaluation of re-mineralizing effect

The present investigation aimed to prepare and evaluate an innovated re-mineralizing oral films made from a blend of hydroxyethyl-cellulose (HEC) and cellulose nanofibers (CNF), loaded with nepheline fluorapatite glass powder. Evaluation of film thickness, folding endurance, disintegration time, surface pH, ions release, together with SEM were carried out. In vitro re-mineralizing effect of the prepared film on demineralized teeth was examined. Results revealed the uniformity in thickness of films, folding endurance more than 300, and the disintegration times more than 24 hrs. The pH values were nearly neutral and high concentrations of calcium and fluoride ions were released. SEM showed a uniformity of glass powder particles distribution. Results of enamel micro-hardness (VHN) and ultra-morphology revealed that there was a significant increase in mean VHN after the remineralization for 15 and 30 days compared to the demineralized specimens. The innovative prepared films are effective approach for remineralization of early demineralized tooth lesions.

Characterizations and Modeling the Influence of Particle Size Distributions (PSD) of Glass Powder on the Mechanical Behavior of Normal Strength Concrete

In this study, a comprehensive experimental investigation and modeling were carried out to examine the impact of two different grain size distributions of glass powder (GP) ((55 µm GP-B)) in various percentages up to 30% on the mechanical characteristics of concrete at different testing ages (7, 28,56, and 91 days). The experimental data observed were utilized to develop different models for characterizing the compressive, splitting, and flexural strength behavior of concrete modified with GP. Results indicated that, up to 25% of cement replacement with GP, the difference in particle size of GP does not have a substantial impact on the mechanical performance of concrete if it is less than 135 μm. Irrespective of GP particle size and the curing days, the increasing percentage of GP replacement up to 10% for compressive strength and up to 15% for splitting and flexural tensile strength tends to marginally reduce compressive, splitting, and flexural tensile strength at 28 days by 4%, 8%, and 6%, respectively. The developed models were found to be well predicted by curing ages, water to binder ratio (w/b), and GP content. Based on the model parameters, the percentage of GP to partially replace cement is much more effective than the particle size of GP, w/b, and curing time in changing the mechanical properties of normal strength concrete. The analytical results were in good agreement with the experimental investigation.

Effect of immersion time of glass powder on mechanical properties of concrete contained glass powder as cement replacement

Abstract The goal of this work is to investigate the effect of immersion time of glass powder (GP) in water before mixing it with the other concrete ingredients on the fresh and hardened properties of concrete. Six immersion times (0, 1, 2, 3, 6 and 12 h) were investigated with different amount of GP as cement replacement (0, 2.5, 5, 10 and 20%). The dissolution of GP in water leads to form more Na ions than Ca ions, because Na ions have less mobility than Ca ions. The concentration of Na decreased as a function of immersion time as it bonds with the SiO2 on the surface of GP particles. Immediately after putting the glass powder in the water, the workability of concrete decreased with the increase of GP content due to the sorption of water molecules on GP particles. As the immersion time increased the workability of concrete increased with the amount of glass powder due to the bleeding effect of the water from the GP. The optimum compressive strength was obtained at 2.5 and 5% GP mixes and at 3 h and 6 h immersion time. At early age, the higher compressive strength is originated from the double effect of the development of pozzolanic reaction due to the increase of the free ions in the water before mixing with the concrete and the packing filling effect of glass powder. The densification of the transitional zone between the cement paste and the aggregate leads to higher compressive strength of concrete. Later, at long curing time, the increase of the compressive strength is correlated to the progress of the pozzolanic reaction of the GP.

Improvement of early-age properties for glass-cement mortar by adding nanosilica

Poor early-age performance (e.g. lower early strength, longer setting time) is an important technical challenge for the application of blended cementitious materials containing low reactivity or high volumes of supplementary cementing materials. In this study, the mechanism of using nanosilica (NS) to improve the early-age properties for cement mortars blended with glass powder (GP) and glass aggregates has been investigated. The results indicate that the addition of NS into glass-based cement mortar largely improved the early stiffening which was dependent on high specify surface area of the NS rather than cement hydration. Combining the use of NS and GP was conducive to compensate the delayed setting times and the strength losses caused by the incorporation of GP. These beneficial behaviors were associated with the physical, acceleration, pozzolanic and pore refinement effects of NS. In terms of heat of hydration, the inclusion of NS intensified and accelerated the appearance of the third exothermic peak (AFt to AFm) due to the absorption of sulfate ions by the increased C-S-H formation. Also, the total hydration heat liberated was found to correlate linearly with the corresponding early-age compressive strength. Microstructural analysis suggest that NS significantly helped to densify the microstructure of the GP blended cement matrix and improved the interface between the GP particle and the binder matrix. This was verified by the contribution of NS on refining the coarse pore size caused by the use of GP as a replacement of cement.

Reactivity of Glass Powder in Aqueous Medium

Recycled glass powder (GP) has recently been widely used as a complementary cementitious material to replace a part of the Portland cement in concrete. However, unlike the chemistry of the Portland cement hydration, more studied and mastered, the mechanism of GP reaction that occurs in-situ during the mixture hydration, is less studied. To overcome this, a first study was focused on the reactivity of the anhydrous glass powder surface over time and its effect on physico-chemical and mechanical properties of concrete. The results showed a very good stability of GP surface. Actually, Portland cement mortars incorporating 20% GP at different ages exhibited the same required properties. The second step, which is the subject of this paper, consists of studying the behavior of GP alone in water and identifying species likely to involve in the hydration reaction in presence of the cement. pH of suspensions and chemical composition of leachates were monitored respectively by pH-meter and inductively coupled plasma mass spectrometry (ICP-MS) as a function of contact time, water-to-solid mass ratio (W/S) and GP particle size. Results reveal an instantaneous increase of pH after mixing GP with water resulting in the passage of surface alkali ions in the solution. Moreover, an enhancement of silicon content in solution is observed suggesting a partial dissolution of the glass network. The dissolution rate increases with increasing W/S ratio and decreasing particle size. Thus, dissolved silica species would react with portlandite from cement hydration explaining good mechanical properties generally observed in concrete containing GP at long term. Accordingly, due to its high amorphous silica content, GP could be an excellent alternative for conventional supplementary cementitious materials such as fly ashes which are not locally available.