Particle Size Of Glass Powder Research Articles

Cost-effective way of improving the optical properties of phosphor-in-glass by adjusting the particle size of glass powder

The effects of silicate glass particle size and Y3Al5O12: Ce3+ (YAG: Ce3+) phosphor doping concentration on the optical properties of phosphor-in-glass (PiG) samples were investigated. When the average particle size of glass powder was 160, 100, 60, and 30 μm, the transmittance of silicate glass with a thickness of 0.6 mm was 68%, 78%, 62%, and 54%, respectively. With the mixing of 4 wt% YAG: Ce3+ phosphor in each component of silicate glass, the transmitted luminous flux of PiG gradually increased with the increase of transmittance, reaching a maximum of 179.5 lm. Simultaneously, we found that with the increase in transmittance, the photoluminescence (PL) intensity of PiG gradually decreased; however, the total luminous flux of PiG has independent of transmittance. When the doping concentration of YAG: Ce3+ phosphor was 4 wt%, PiG achieved a maximum efficient white light emission of 212.61 lm/W under blue laser excitation at 2.31 W. All results indicate the outstanding feasibility of the prepared YAG-PiG in high-power/high-brightness white light-emitting diodes (WLEDs).

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.

Recycling of Broken Waste Glass as Polyethylene Nanofiller for Electrical Insulating System

This work focuses on the preparation of a high-quality glass powder from the broken windowpane. The expected glass powder must show a high amount of silicon dioxide with fine particle size. The processing technique used in this work is coarse grinding and high-speed vibratory milling under a variety of conditions to get the best quality of glass powder. The particle size and particle size distribution were examined by using DLS technique. The chemical composition was examined by EDX together with FT-IR and XRF spectroscopies. The results showed that the wide range of particle size distribution occurred in all milling conditions, which approximately ranged from 0.3 to 7 µm, and the 270 min-milling time showed the smallest particle size of glass powder. The chemical analysis showed that the glass powder is rich in silica which contained about 70.47% of SiO2. After that, the various ratios of the glass powder/HDPE composites were formed by using the traditional casting method. The physical and electrical properties were investigated for all composites. The results showed that after adding glass powder into the HDPE matrix, the εr value significantly drops due to the inorganic filler suppressed polarization within the systems. For the resistivity, the ρ value significantly increases after adding glass powder to the HDPE matrix for all compositions because this filler promotes the hinder of electric current flow. Finally, it can conclude that the waste glass powder can use as a filler in the HDPE-based composite as better as the commercial SiO2 powder for the electrical insulting application.

Utilization of Waste Glass Powder as a Filler in Epoxy Resin Based Composite

This work focuses on the preparation of a high-quality glass powder from broken household waste glass. The expected glass powder prepared from household waste must show a high amount of silicon dioxide with fine particle size. The processing technique used in this work is coarse grinding and high-speed vibratory milling under a variety of conditions to get the best quality of glass powder. The particle size and particle size distribution were examined by using DLS technique. The chemical composition was examined by EDX together with FT-IR and XRF spectroscopies. The morphology of all glass powders was investigated by SEM. The results showed that the wide range of particle size distribution occurred in all milling conditions, which approximately ranged from 1 to 10 µm, and the 4 h-milling time showed the smallest particle size of glass powder. The chemical analysis showed that the glass powder was rich in silica which contained about 67% of SiO2. After that, the various ratios of the glass powder/epoxy resin composites were formed by using the traditional casting method. The physical, mechanical and electrical properties were investigated for all composites. The results showed that the Hv value of the glass powder/epoxy resin composites exhibited a much higher value than that of pure epoxy resin. For the electrical properties, after added 1 wt% of glass powder into the matrix, the εr and R significantly increased. The Eb value of the composite prepared from waste glass powder showed no significant difference from the composite prepared from commercial SiO2. So, it can say that the waste glass powder can be used as a filler in the epoxy resin-based composite as well as the commercial SiO2 powder for the electrical insulting application.

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.

Effects of glass on densification and interfacial bonding of LTCC co-fired Ag electrode

In this paper, the effects of particle size and content of glass additive on the sintering densification, interfacial bonding and electrical properties of silver electrode of LTCC were investigated. The particle size of glass powder would mainly affect the densification rate of electrode film and the uniformity of glass phase distribution. The content of glass played a key role in the density of electrode film, the distribution of glass phase and the interface bonding. When the relative content of glass was low, the glass phase could not wet the silver powder effectively. Thus, the silver film was not dense and the interfacial adhesion was weak. When the relative content was too high, there would be too much glass phase at the surface and interior of the electrode film, which would increase the silver film resistance. By adjusting the particle size and relative content of glass, the co-firing compatibility of LTCC and thick film silver electrode could be better realized. When the content of glass additive was 1.0 wt%, the sintered film illustrated the optimum performance of densified microstructure and low sheet resistance of 1.32 mΩ/sq.

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.

Preparation of fully dense and magnetically controllable CaO-Al2O3-SiO2-Na2O-Fe3O4 glass ceramics by hot pressing

Fully dense and magnetically controllable glass ceramics was successfully synthesized by method of hot pressing using CaO-Al2O3-SiO2-Na2O glass powder and Fe3O4 powder as raw materials. The influences of sintering temperature and time, content and particle size of Fe3O4, as well as particle size of glass powder on the densification and magnetic properties of samples were investigated. It was found that the saturation magnetization gradually increased with increasing magnetite content. In addition, the samples containing smaller size magnetite particles had a higher coercivity. However, for samples using smaller size glass powder, magnetite particles could partially dissolve into the glass matrix, which led to the decrease of saturation magnetization and the increase of coercivity. It was also concluded that the precipitation of crystalline phase from smaller size glass powder caused the decrease of degree of densification, and after decreasing the sintering temperature, the degree of densification of product was enhanced.

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.

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.

Review—Phosphor Plates for High-Power LED Applications: Challenges and Opportunities toward Perfect Lighting

In the past decades, solid-state lighting based on phosphors as energy converters has been a fast-growing industry. Phosphor-converted white light-emitting diodes (pc-wLEDs) enable high-power applications and miniaturization; for this, the phosphor must have good stability and high efficiency. In order to satisfy this demand, phosphor plates have been proposed instead of conventional organic-based phosphor binders. In this review, such phosphor plates are categorized according to their synthesis methods, and the advantages and disadvantages of each category are detailed. In addition, we describe the major aspects of phosphor plates that require improvement for applications in high-power devices. For the fabrication of high-power LEDs, the phosphor configuration, color purity, porosity, and particle size of glass powders are key properties to enhance the luminescence efficiency and reduce the generation of heat inside wLED packages, thereby improving thermal stability.

Improved the quality of the glass/glass laser bonding through the optimization of glass powder size in planetary ball mill

ABSTRACTGlass paste for laser bonding is composed of low melting point glass powder, organic carrier and additives. As the particle size of glass powder is increasing, the crack defects of glass frit film growing and it is not conducive to the encapsulation air tightness. This work has succeeded in optimizing processing parameters of ball milling and investigating the effect of different parameters on powder particle size through orthogonal test. The result show that ball-to-powder ratio (weight ratios) has the primary influence on the particle size. An optimized ball-to-powder ratio of 3:1 exhibits the best performance. The best performance of glass powder which milled by optimization parameters can be attributed to the quality of glass/glass laser bonding. The grinding glass frit film has not appeared cracks after laser bonding, and the shear strength values is higher than the not grinded.

EFFECT OF GLASS POWDER ON ACID RESISTANCE OF ENAMEL COATING

Enamel glaze was added with glass powders of different sizes and masses and fired into enamel coatings on the surface of low-carbon steel. Acid resistance of the enamel coatings in H2SO4 solution was analyzed by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and mass loss of acid corrosion. As was discovered in research, the acid corrosion quantity in the enamel coatings decreased with the decrease in the particle size of the glass powder when the particle size of the additive glass powder reduced from 100[Formula: see text][Formula: see text]m to 1–2[Formula: see text][Formula: see text]m and heated the prepared enamel coatings in the H2SO4 solution until 80[Formula: see text]C and kept for 48[Formula: see text]h. When the additive amount of the glass powder increased from 5% to 20%, the surface of the enamel coating was smooth and flat with good glossiness and without defects like obvious bubbles and cracks, and the acid corrosion quantity decreased with increase in the additive amount of glass powder, which decreased from 43.24[Formula: see text]mg/cm[Formula: see text]d to 4.28[Formula: see text]mg/cm2.d, satisfying the acid-proof performance requirements of industrial enamel coatings.

Preparation of Poriferous Glass Bodies by Useless Glasses Partial Sintering Process

The porous glass has a high chemical, thermal, and mechanical resistance, which results from a rigid and incompressible silica network. In the present manuscript, porous glasses were prepared and characterized by partial sintering of waste glasses. Polyvinyl alcohol was added as a binder to the glass powder and the mixture was uniaxially cold pressed under two different forces, followed by sintering at 850°C. The effects of thermal history, particle size of glass powder, binder content, and applied pressing forces on pore size and total porosity of fabricated porous glasses were investigated, and final products with the average porosity of 25% were prepared. The average pore size of the specimens was determined using mercury porosimetry. The morphology of the porous glasses was observed by scanning electron microscopy. The results showed that the average pore size of the samples decreased by increasing binder content due to better compaction of the mixed powder.

Crystallization behavior of bismuth oxide nano-glass studied via in situ transmission electron microscopy

The substitution of bismuth oxide for lead in glass and decreasing the particle size of glass powders to the nanoscale have both attracted considerable interest as techniques for decreasing the maximum firing temperature and alleviating environmental problems. However, crystallization during firing is an issue that needs to be solved. In this study, we investigated the sintering behavior of nanosized bismuth oxide glass and the mechanism of its crystallization. The crystallization behavior during sintering was analyzed by hot-stage microscopy. The microscopic sintering interaction between individual nanoglass particles was observed by in situ transmission electron microscopy. The glass softening and densification starting temperatures were dramatically decreased when decreasing the particle size from micro to nanoscale. Based on this study, the bloating of nanostructured bismuth oxide glass starts at 370°C. This corresponds with the dissociation temperature of bismuth oxide. Therefore, the bloating phenomenon during the sintering of the nanoglass powder is attributed to the thermal dissociation of bismuth oxide.

RETRACTED ARTICLE: Application of partial sintering of waste glasses for preparation of porous glass bodies

Porous glasses were prepared by partial sintering of waste glasses. Polyvinyl alcohol was added as a binder to the glass powder and the mixture was un-axially cold pressed under two different forces, followed by sintering at 700 °C. The effects of thermal history, particle size of glass powder, binder content and applied pressing forces on pore size and total porosity of fabricated porous glasses were investigated and final products with the porosity of 15–32 % were prepared. The average pore size of the specimens was determined using mercury porosimetry. The morphology of the porous glasses was observed by scanning electron microscopy. These produced porous glasses can be used for selective and accurate filtration.

Effect of Heat Treatment Schedules and Glass Powder Particle Size on Glass Infiltration in Porous Alumina Preforms

Glass infiltrated alumina is one of the popular materials for fabrication of dental prostheses. Achieving complete and uniform glass infiltration is important to achieve desired properties in dental prostheses. This study examined the role of various factors on glass infiltration in sintered porous alumina preforms (porosity ~ 27%). Observations on infiltration in porous alumina samples at a heating rate of 3°C/min at 1100°C for 2 h showed residual glass on the surfaces of the samples indicating incomplete infiltration. Rapid heating of the samples to the peak infiltration temperature by introducing the samples into a preheated furnace resulted in complete infiltration of glass into the samples in <90 min. In addition to heating rate during infiltration, influence of soaking duration and the particle size of glass powder on glass infiltration were also examined.

Crystallization Behavior of Lithium Iron Phosphate Glass Powders in Different Atmospheres

Crystallization behavior in different atmospheres (air, Ar, and 7% H2/Ar) of lithium iron phosphate glass (33Li2O–33Fe2O3–1Nb2O5–33P2O5 (LFNP)) powders with different sizes of 2–1000 μm was examined. The crystallization peak temperature (Tp) in Ar and 7% H2/Ar decreased with decreasing the particle size of glass powders, but the value of Tp in air was independent of particle size. The crystallized glass obtained by heating to Tp showed the formation of the α‐Li3Fe2(PO4)3 and LiFePO4 crystalline phases. Fe2O3 crystals were formed only in the inside of crystallized glass plates in the heating in air. The crystallization of LiFePO4 was largely enhanced in the particle size of <2 μm during the heating in Ar and 7% H2/Ar atmospheres. The main crystallization mechanism in LFNP glass was found to be surface crystallization. Significant shrinkages were observed for glass compacts (pellets) in the heating in 7% H2/Ar. These results suggest that controlling particle sizes and atmospheres enables the design the morphology of LiFePO4 crystals in LFNP glass.

Effect of frit size on sintering, crystallization and electrical properties of wollastonite glass-ceramics

Wollastonite glass-ceramics were prepared through pressureless sintering. The sinterability of the prepared samples of the glassy powder in the system (SiO 2–CaO–Na 2O–Fe 2O 3–WO 3) was investigated in the temperature range 720–900 °C and soaking time of 180 min. The influence of the increase in the glass powder particle size on the sinterability and dielectric properties of the glass-ceramic samples was studied. The sintered specimens were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) methods. XRD analysis revealed that wollastonite was the main crystalline phase in the sintered glass-ceramics. Dielectric properties such as dielectric constant and dielectric loss were measured via a network analyzer at 10 GHz. It was observed that the increase of the glassy powder particle size improved the sinterability and dielectric properties of the glass-ceramic specimens. Wollastonite glass-ceramics with 16 μm particle size had maximum constant and minimum loss (ε r = 10.10 and tan δ = 0.005) compared with the other glass-ceramics.

Study on Low Temperature Sintering Behaviour of CaO-B<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub> Glass Ceramics

CaO-B2O3-SiO2 glass ceramics were prepared by powders of different particle sizes. The relationship between CBS powder characteristics and structures was studied by XRD and SEM, and the effect of powder characteristics on sintering properties, dielectric properties at 10GHz, thermal properties (CTE) were investigated to obtain low-temperature sintered glass ceramics. The results showed that the median particle size of glass powders reduced, sintered temperature and apparent porosity decreased. But at the same time, bulk density and thermal expansivity increased. The sample with the powders of D50=2.34μm could be sintered at 850 with the density about 2.615g•cm-3 and the water absorption about 0.16%. Having a dielectric constant of 6.16 and a dielectric loss of 1.9×10-3 at 9.98GHz, the sintered sample could satisfy the requirements of the substrate materials used in LTCC in some fields.