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The effect of Dysprosium concentration has been studied in glasses of the system 30 SiO2 + 30 Li2O + (40−x) B2O3 + x Dy2O3 glass system where x = 0.5, 1, 2.5, 5 and 10 mol%. FT-IR studies were performed to understand the functional groups of the network involved in the host glass. The optical band gap is found in the range of 3.84–3.5 eV. From the absorption spectra, the experimental data were compared with the theoretical data computed by Judd–Ofelt theory. Nephelauxetic ratio (β) and bonding parameters (δ) computed using the absorption spectrum. The Judd–Ofelt parameters (Ω2, Ω4, and Ω6) obtained demonstrates the covalent and asymmetric nature of dysprosium ions. From the visible emission spectra, the intensity ratios were calculated from yellow to blue and the relative differences were discussed based on the concentration of Dy3+ ions. CIE chromaticity coordinates were calculated for all glass samples. A CIE chromatogram shows a glass containing 0.5 mol% Dy2O3 with color coordinates X = 0.32 and Y = 0.33 with the highest emission intensity. These glasses have great potentials for lasers and white LEDs (Light-Emitting Diode) applications.

Cold-crucible induction melting (CCIM) technology has been intensively studied as an advanced vitrification process for the immobilization of highly radioactive waste. This technology uses high-frequency induction to melt a glass matrix and waste, while the outer surface of the crucible is water-cooled, resulting in the formation of a frozen glass layer (skull). In this study, for the fabrication of borosilicate glass waste form, CCIM operation test with 60 kg of glass per batch was conducted using surrogate wastes composed of Cs, Sr, and Nd as a representative of highly radioactive nuclides generated during spent nuclear fuel management. A 60 kg-scale glass waste form was successfully fabricated through melting and draining processes using a CCIM system, and its physicochemical properties were analyzed. In particular, to enhance the controllability and reliability of the draining process, an air-cooling drain control method that can control draining through air-cooling near drain holes was developed, and its validity for draining control was verified. The method can offer controllability on various draining processes, such as molten salt or molten metal draining processes, and can be applied to a process requiring high throughput draining.

Rare earth (RE)-containing crystals have been investigated as media for the immobilization of RE fission products from nuclear waste streams. During reprocessing of spent nuclear fuel, fission products including REs, alkalis, and alkaline earths released from the fuel. One viable option to immobilize the RE fission products is to incorporate them into chemically durable crystalline phases in specific waste forms. This study summarizes the crystal structures and synthesis methods of six RE-containing compounds that have applications in remediation of RE fission products. These compounds include oxyapatite (AE2RE8(SiO4)6O2), oxychloride (REOCl), borosilicate (RE3BSi2O10), pyrochlore (RE2M2O7), monazite (REPO4), and perovskite [REMO3] where AE denotes alkaline earth metals and M denotes transition metals. This review provides an overview of literature on the usage of these six compounds for immobilizing RE fission products and summarizes different synthesis methods for producing these compounds. Comparisons of structural parameters with different REs in each compound are also discussed.

Mo–57Si–10B (at.%) coating was prepared by the spark plasma sintering (SPS) technique on a 2D woven Cf/SiC composite, and the oxidation behavior of the bare and the coated Cf/SiC samples at 1300 ​°C were investigated. The coating was composed of a fine MoSi2/MoB/SiO2/Mo2B5 out layer and the inner SiO2 interface layer. The mass gain percentage was approximately 0.25% after oxidation at 1300 ​°C for 100 ​h. The coated Cf/SiC substrate was effectively protected, owing to the rapid formation of the dense and protective borosilicate layer on the coating, the excellent microstructure stability of the coating and the inner SiO2 interface layer.

In this report, we have systematically evaluated the role of boron in regulating the degradation, apatite formation and antibacterial properties of bioactive glasses by substituting SiO2 with B2O3 in S53P4 based glass composition. The structural analysis of the glasses has been carried out using neutron diffraction and Raman spectroscopic techniques. The structural analysis of S53P4 base glass has revealed the presence of silicate and phosphate units in the form of Q2Si, Q3Si and isolated Q0P units. With the increasing replacement of SiO2 with B2O3, Raman spectroscopy revealed the formation of non-ring metaborate units and borate rings consisting of both BO3 and BO4 units at the expense of Q2Si and Q3Si units. Furthermore, DSC, HSM and dilatometry results confirmed that the sinterability parameter (Sc) and fragility index (m) values of borosilicate bioactive glasses help in achieving superior sintering and thermal processing without devitrification. Additionally, in vitro SBF immersion studies revealed an accelerated release of Si4+ and Ca2+ ions from the borosilicate glasses. In vitro antibacterial assays against E.coli bacterial inoculum illustrate the critical role of B2O3 in the bioactive glass composition.

B4C modified HfB2-SiC coating for C/C substrate was designed to expand the application of HfB2-SiC based coating in low-medium temperature environment. The oxidation protection behavior of HfB2-SiC based ceramic coatings with and without B4C at 1073, 1273 and 1473 K was tested and analyzed. The experimental results reveal that the oxidative damage of HfB2-SiC coated C/C reduces by over 20% after introducing B4C, which may be due to the protection of borosilicate glass with more suitable viscosity during oxidation. Meanwhile, B4C can improve the oxidation protection ability of HfB2-SiC coating best at 1473 K. And the introduction of B4C can reduce the mass loss of HfB2-SiC coated C/C sample by 77.6% after oxidation for 58 h at 1473 K. The fluidity of glass film becoming better with temperature-rising, and the fluid borosilicate glass layer makes the coated samples have the best anti-oxidation properties at 1473 K among these three temperatures.

Nickel-supported CHA-type zeolites with different framework compositions including borosilicate, gallosilicate and aluminosilicate were synthesized. The effect of heteroatoms in the framework on th...

Embedding all-inorganic cesium lead halide CsPbX3 (X=Cl, Br, I) perovskite quantum dots (PQDs) PQDs into glass is one of the most effective strategies to improve their optical, thermal and chemical stabilities. Herein, by using PbO instead of PbBr2 as the lead source, it is effective to lower the melting temperature and reduce the volatilization pollution from lead halide raw materials. Thus, a high-purity CsPbBr3 PQDs embedded glass with 71.5 % PLQY was successfully prepared. The thermal stability, and photo-aging properties were also improved. By simply changing the halogen element, the red and blue CsPbX3 PQDs embedded glasses were successfully prepared. The white LED fabricated by coating obtained green/red CsPbX3 PQDs embedded glass on a blue chip displays high color gamut of 121.9 % NTSC standard and >91.1 % Rec. 2020 standard, which embodies the great potential of PQDs embedded glass in lighting and display fields.

Most research activities in the nuclear mining industries are directed to separation of heavy and radioactive minerals from rocks and sediments. This process is completed without utilizing tailing and mineral waste materials. Tailing materials containing radioactive wastes are considered as a major environmental problem; especially with increasing the exploration of metals and lower grade mineral deposits. In the present work, borosilicate glass could be prepared for immobilizing these nuclear wastes in the designing compositions by melting at 1200–1250 °C. NaI (TI) gamma-ray spectroscopy system was used to detect 238U, 232Th, 226Ra, and 40K concentrations in tailing materials and prepared glass to emphasize their safe dose. The produced glass was characterized by XRD, SEM, FTIR, and UV spectrophotometer. Vickers hardness and leaching properties were also studied. The results showed that compact - structured glass with high durability towards groundwater was obtained. All studied environmental parameters indicated that the glass radiation dose was lower compared to international averages, thus the glass can be safely used in nuclear waste immobilization.

This paper investigates the Digital Glass Forming (DGF) process for printing transparent fully-dense borosilicate structures. In this process, glass is deposited by laser heating the intersection of a continuously fed filament with the workpiece. The laser provides control of the surface temperature but thermal diffusion through a low-thermal conductivity filament limits deposition rates. Introducing the laser from the side is shown to deliver energy directly to the glass that will form the interface with the workpiece. This permits the filament to deform the molten zone and significantly improves deposition rates.

In a biomedical drug delivery system, liquid medication is provided to the patient through a saline solution, administered in tiny drops. The spread of the medicine in the solution is an essential aspect for the solution to become homogeneous. The present study introduces a combined pump and active–passive mixer arrangement consisting of dual piezoelectrically actuated 1-degree of freedom (DOF) Aluminium cantilever beams. The free end of each beam is attached to a borosilicate glass tube set-up that works as both pump and a mixer. The setup consists of two vertical tubes, connecting channels, a glass bulb, and a coiled tube. When the piezoelectric actuated cantilever beam is excited by an excitation voltage, it deflects and vibrates along with the glass tube arrangement resulting in the vertical tubes pumping liquid from the two separate glass containers due to the mechanical vibratory movement. The connecting channels pass the pumped fluid into the vibrating glass bulb and the coiled tube where these two liquids mix. We tested the mixing executions of four different geometries, G-1 – G-4, based on changed δ (coil curvature ratio), p (pitch), and n (number of windings). Initial pumping was started at 90 VP-P input voltage for all geometries, and the observed flow rate and velocity were 2.91 ml min−1 and 0.9160 mm min−1 for G-1 geometry. A UV–visible spectrophotometer was used to evaluate the mixing execution by measuring the solution's absorbance values before and after mixing.

In this research, Nd2O3 doped sodium borosilicate glasses were produced using a standard melt quench technique. Various characterization techniques, such as XRD analysis, FTIR spectroscopy, density analysis, absorption and photoluminescence spectroscopy measurements, were used to investigate the synthesized glassy samples. XRD spectra demonstrated the amorphous existence in the studied glasses. FTIR analysis was used to determine the stretching and bending vibrations of various borate groups. The high molecular weight of Nd2O3 and the broader ionic radius of Nd3+ ions resulted the rise in molar volume (Vm) and density (ρ) with inclusion of Nd2O3. The optical band gap was observed to shrink with increasing Nd3+ ion concentrations. The intensity of Nd3+ emission spectra improved from 0.5 mol per cent to 1.0 mol per cent with Nd2O3 material and the concentration quenching was reported at concentrations higher than 1.0 mol percent. The emission spectra of the synthesised glass shows three notable peaks found at 902 nm (4F3/2→4I9/2), 1063 nm (4F3/2→4I11/2) and 1334 nm 4F3/2→4I13/2 of Nd3+ ions transitions.

Metallic mirror coatings with high reflectivity using Au thin films deposited onto a Borosilicate BK7 glass substrates by a sputtering technique using ionic coating system (KIC-1A) were investigated. In order to facilitate the process of calculating the relationship between deposition duration and thin film thickness to reach to a certain thickness, so we have described and calculated the relationship between deposition duration and thin film thickness by theoretical analysis and then simulated by polynomial function. This study showed the relationship between the reflection and thin film thickness, where the highest value of the reflective coatings of 90.5% was obtained at thin film thickness of 153 nm.

There are several ways to create optical filters on glass, such as the low-cost sol-gel coating. However, to make this process even more effective and flexible, a laser instead of a conventional furnace process was used to anneal the borosilicate glass samples. In previous studies, it was demonstrated that it is possible to generate similar refractive indices and film thicknesses with a CO2 laser as with the furnace method. In this study, TiO2-coated borosilicate glasses are annealed with a CO2 laser. In particular, the main goal is to scan a large processing area (up to 475 x 468 mm2) and to achieve process speeds comparable to those in the furnace process. Microscopic images show a homogeneous layer and an ellipsometrically determined refractive index comparable to the reference sample from the furnace (laser sample: 2.32; furnace reference: 2.20). With a suitable process setup, it is therefore possible to process glass efficiently on an industrial scale.

Thermoluminescence glow curves of gamma-irradiated Samarium doped lithium borosilicate glass were investigated. The number of overlapping peaks is determined using the Repeated Initial Rise (RIR) method. The glow curves were deconvoluted into four overlapping peaks. The trapping parameters such as activation energy E, frequency factor (s), and kinetic order (b) for each peak are determined. The obtained results indicated that the Lithium borosilicate glass doped with Samarium has four electron trap levels with the average activation energies of 0.82,1.01,1.21, and 1.31eV, respectively. Thermal fading analysis of the individual peaks based on the deconvolution data is performed. The obtained results showed high thermal fading of the first peak while high thermal stability of the second and third peaks compared with the other peaks. These results could be used to explain some observed properties such as high thermal fading and light sensitivity for such thermoluminescence material. Moreover, the obtained results may be helpful to minimize the fading corrections in the dosimetric applications.

In this work, Eu3+-doped CsPbCl2Br1 in borosilicate glass was successfully synthesized by the melt quenching annealing technique and crystallization method. This work reports a novel Eu3+-doped CsPbCl2Br1 perovskite quantum dots (QDs) glass with high sensitivity for optical temperature sensing. The relation of fluorescence intensity ratio (FIR) with the temperature was studied in the temperature range of 80–440 K. Notably, the maximum absolute temperature sensitivity (Sa) and relative temperature sensitivity (Sr) of Eu3+-doped CsPbCl2Br1 perovskite QDs glass can reach as high as 0.0315 K–1 and 3.097%/K, respectively. Meanwhile, Eu3+-doped CsPbCl2Br1 QDs glass demonstrates good water resistance, excellent thermal and cold cycling stability performance. The Eu3+-doped QDs glass materials can bring inspiration to the future exploration of rare earth ion-doped QDs glass material on the application of optical temperature sensing in the future.

To elucidate the crystal growth process of hematite in high-temperature lead-free multicomponent alkali borosilicate glass, which is essentially important to control the color of red overglaze enamels, frit and hematite mixture is heat-treated and subjected to microscopic observations. Hematite particles slightly grew due to sintering at low temperature. Once the glass matrix formed near the softening point of frit, hematite dissolved into glass fluid. Hematite crystal growth concomitantly ensued with decrease in the number of hematite particles via Ostwald ripening as the temperature increased. The grown particles exhibited an anisotropic morphology with straight outlines reflecting crystal planes, the morphology of which is completely different from those grown by sintering and particles prior to heating. These results suggest that comprehensive understanding of frit and hematite from the perspectives of glass science and chemistry as well as powder technology are important to truly control the color of red overglaze enamels.

In the process of magnetorheological polishing of planar optical elements, in order to solve the problem of uneven material removal rate and improve the polishing efficiency of planar optical eleme...

The effect of LaB6 (7, 10, and 14 vol pct) addition on oxidation behavior of spark plasma-sintered ZrB2–20 vol pct SiC composites involving heating under non-isothermal condition till 1400 °C, and isothermal and cyclic exposures at 1300 °C to 1500 °C have been examined. The mass gain of the composite with 14 vol pct LaB6 is found as the highest during non-isothermal oxidation, whereas it appears as the least on isothermal exposure for 24 hours at 1400 °C or 1500 °C. The mass gain after 24 cycles of 1-hour exposure at 1300 °C to 1500 °C is found to be lower than that recorded under isothermal condition for all the composites, with the difference decreasing with LaB6 content. The oxidation exponent (n) is found to decrease to near parabolic rate law with the increase in cyclic exposure temperature. The parabolic rate constant (kp) is found to decrease with the increase in LaB6 content after a few cycles of exposure at all the investigated temperatures. The oxide scales formed on isothermal exposure at 1400 °C or 1500 °C have shown a thin La2Si2O7 layer with borosilicate glass (BSG) as the outer layer, followed by layers containing BSG along with coarse and fine ZrO2, and a SiC-depleted ZrB2 layer. The oxide scales formed during cyclic exposure contain an outer compact layer comprising BSG, La2Si2O7, and ZrSiO4, followed by ZrO2 + BSG. Additionally, a SiC-depleted layer is found at the oxide–composite interface on cyclic exposure at 1500 °C for 24 hours, and at 1400 °C for 100 hours. The outer compact layer appears to have a critical role in protection against oxidation, with kp decreasing with the increase in its thickness.

State-of-the-art abrasion resistance of glass ceramic coatings (GCCs) is set by dense, low closed porosity, defect- and micro-stress-free microstructure since GCCs have low fracture toughness. Tita...

Ca10(PO4)6F2 (CaFAp) is one of the potential matrices for the immobilization of fluoride containing waste. Studies on the substitution of Nd to CaFAp are carried out to explore the solubility limit of Nd in CaFAp. A series of Ca10-xNdx(PO4)6F2 with x = 0–1.2 compositions were synthesized by solid state reaction route. The product was found to form on heat-treatment at 973 K/4h in air. The product was characterized by X-ray diffraction (XRD), FTIR, Raman spectroscopy and thermo-gravimetric analysis followed by differential thermal analysis (TGA-DTA). Results obtained in this study shows the solid solubility limit of Nd is

Aluminum-containing raw materials for the synthesis of aluminum-borosilicate glasses for E-glass fiber should be rationally chosen to comprehensively assess their effect on the glass melting processes. The characteristic properties of the chemical, phase, and granulometric composition of the raw materials such as metallurgical alumina, non-metallurgical alumina, disthene, and kaolin were under study. It was revealed that the type of aluminum-containing raw materials significantly influenced the rate of glass formation processes and heat consumption required for these processes. The efficiency of aluminum-containing raw materials is influenced by the following factors: the phase composition, which determines the sequence and rate of phase transformations, as well as the heat-absorbing ability of the furnace batch and glass melt. The most energy-efficient material is non-metallurgical alumina of the White Alumina brand. Using it facilitates saving energy resources for glass formation processes from 2.64% to 16.30% as compared with other types of aluminum-containing raw materials. The use of kaolin proves to be the least efficient due to the additional energy consumption for the process of destruction of the crystal structure of kaolinite, the reduced thermal conductivity of the batch, and the thermal transparency of the borosilicate glass melt.

Application-specific optical glass properties are achieved by utilizing complex material compositions. This can be problematic in reactive plasma-assisted deterministic surface processing since a non-volatile surface layer may form depending on the glass composition, which affects the etch rate and thereby the local etching depth. In this investigation, a model algorithm is proposed to tackle some restrictions in applying fluorine-based plasma jet as etching tool utilized for freeform surface machining of optics made of complex glass composition, like borosilicate crown glass (e.g., N-BK7®). In this regard, firstly an analytical model is proposed for estimating the depth-dependent etch rate function. Subsequently, a recursive simulation algorithm is introduced for convolving the derived depth-dependent etch rate function with the given dwell time matrix to simulate a deterministic freeform generation process. By the proposed simulation algorithm, the impeding influence of the residual layer on the reduction of etching depth is computed prior to a real experiment in order to scale the local dwell time to ensure the targeted local removal. Finally, the simulated freeform shape is compared with the corresponding result of an etching experiment to validate the feasibility of the proposed approach.

The glass system was fabricated using traditional procedures. Fourier Transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), and radiation techniques were used to characterize the glasses. In an experiment, XRD was used to assess the system’s amorphous state. As the density of the manufacturing glasses rises, the molar volume declines. Borosilicate network is unaffected due to incorporation of BaO. With incorporation of BaO, FTIR results show a conversion from BO3 to BO4. The gamma ray shielding constraints were defined using the Phy-X software. Finally, adding BaO to the glass network improved the gamma shielding characteristics. As a result, this glass system should be used to shield against radiation.

The pig is the most widely used large animal model in Europe, with cardiovascular research being one of the main areas of application. Adequate refinement of interventional studies in this field, meeting the requirements of Russel and Burchs’ 3 R concept, can only be performed if blood-contacting medical devices are hemocompatible. Because most medical devices for cardiovascular interventional procedures are developed for humans they are tested mostly for compatibility with human blood. The aim of this study was therefore to determine whether there are differences in behavior of porcine and human platelets when they come into contact with glass, which was used as an exemplary thrombogenic material. For this purpose changes of platelet count, platelet volume and platelet expression of the activation markers CD61, CD62P and CD63 were measured using a modified chandler loop-system simulating the fluidic effects of the blood flow. Minipig and human platelets showed significant differences in number and volume, but not in activation after 4–8 min exposure to glass.

In the dry etching of borosilicate glass (BSG), the process gas reacts with the impurities of borosilicate glass and forms a non-volatile compound layer on the surface. This surface compound layer (SCL) makes it difficult to control the surface morphology and device structure dimension with precision and significantly influences the etch rate. We examined the influence of SCL on the etch rate of quartz and BSG and discussed its etching mechanism depending on the thickness of the SCL. The formation of SCL was dominated by both the plasma gas composition and substrate material, and the etching regime can be defined by the thickness of the SCL. A thin SCL was formed on the BSG by CF4/Ar gas plasma etching, and the etch rate was suppressed by the SCL. A significantly thin SCL was formed on the quartz specimens under in same etching conditions, and a direct etching reaction was occurred. As the ratio of physical etching gas (Ar) increased, both the ion energy flux and the physical ion bombardment increased and consequently improved the etch rate. The SCL plays the role of an F radical supplier, while the thick SCL reduces the etch rate because it takes time for the etchants to transit from the surface to the interface. The SCL acts as a barrier in the etching reaction, which could be adjusted by the regulation of the etching gas composition or the plasma parameters, such as the inductive power and the bias power of the RIE reactor. [2021-0071]

In this work, the effect of varying content of B2O3 with respect to SiO2 on mechanical and bioactivity properties have been evaluated for borosilicate bioactive glasses containing SiO2, B2O3, CaO and P2O5. The bioactive glasses have been synthesized using the sol–gel technique. The synthesized glasses were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and Field Emission Scanning electron microscopy (FESEM). These bioactive glasses were fabricated as scaffolds by using polymer foam replication method. Subsequently, in vitro bioactivity evaluation of borosilicate bioactive glass was done. Based on the XRD and energy-dispersive X-ray spectroscopy (EDS) results showing good apatite-formation ability when soaked in simulated body fluid (SBF), one of the bioactive glass (BG-B30 containing 30 mol% B2O3) was selected for further study. The compressive strength of the bioactive glass scaffolds was within the range of trabecular bone. However, it was found near the lower limit of the trabecular bone (0.2–12 MPa). Therefore, BG-B30 scaffold was reinforced with carbon nanotubes (CNTs) to allow for mechanical manipulation during tissue engineering applications. The compressive strength increased from 1.05 MPa to 7.42 MPa (a 606% increase) after reinforcement, while the fracture toughness rose from 0.12 MPa √ m to 0.45 MPa √ m (a 275% increase). Additionally, connectivity of the pores in the CNT reinforced BG-B30 scaffolds were evaluated and the pores were found to be well connected. The evaluated properties of the fabricated scaffolds demonstrate their potential as a synthetic graft for possible application in bone tissue engineering.

We report the unique growth of nanofibers in silica and borosilicate glass using femtosecond laser radiation at 8 MHz repetition rate and a pulse width of 214 fs in air at atmospheric pressure. The nanofibers are grown perpendicular to the substrate surface from the molten material in laser-drilled microvias where they intertwine and bundle up above the surface. The fibers are few tens of nanometers in thickness and up to several millimeters in length. Further, it is found that at some places nanoparticles are attached to the fiber surface along its length. Nanofiber growth is explained by the process of nanojets formed in the molten liquid due to pressure gradient induced from the laser pulses and subsequently drawn into fibers by the intense plasma pressure. The attachment of nanoparticles is due to the condensation of vapor in the plasma.

Lampworking is a valuable skill for students in Chemistry and others in science, technology, engineering, and math (STEM) related fields. The activity described here provides instructors the resources to both learn and teach the fundamentals of lampworking. Soft glass, which can be shaped and fused with a Bunsen burner, is used to improve the accessibility of this activity. The Bunsen burners have been modified so that the angle of the flame is between 45 and 60° rather than 90° relative to the base. This modification significantly improves the lampworking experience according to student feedback. Students ranging from Freshmen to Seniors have participated in this activity. This activity introduces students to skills that can be later used with borosilicate glass for scientific glassblowing projects. This activity is both educational and fun for students in STEM fields as well as nonscience majors. Furthermore, this is an excellent professional development opportunity for educators.

In this study, the ballistic behavior of protective armor plates (PaP) obtained by curing between high structural strength AA7075-T651 aluminum plates by reinforcing with glass balls of two different rubber mixtures whose damping properties were developed with carbon nanotube and glass bubbles fillers were investigated. A total of six PaPs at 27, 30, and 35 mm heights were prepared using two different matrix damping rubbers. High-strength liner rubber used in air bellows is vulcanized on the front and back surfaces of PaPs. Between the PaPs, Ø15.875 and Ø6.747 mm, borosilicate glass balls were placed in a particular arrangement that coincides with the middle of the matrix rubber and does not have any gaps. Liner rubber cured on the front face has managed to hold the energy by forming a layer like clothing around the bullet cores. Glass balls between PAPs play an essential role in the energy absorption of GB-filled mixtures. In contrast, in MWCNT-filled mixtures, they act as a second damping element. The ballistic performance of PAPs prepared with multiwalled carbon nanotubes was determined to be better than those prepared with Glass Bubbles. Thanks to the superior mechanical properties and high aspect ratio of MWCNTs, the penetration and swelling heights of the matrix damping rubbers prepared to have excellent results compared to glass bubbles. With the increase in the thickness of the PaPs prepared with MWCNTs, the deformation effect of the penetration depth and bulging height created by the bullet on the anterior and posterior surfaces decreased. As the thickness of PaP increased from 27 mm to 35 mm, penetration depth decreased by 38%, and bulging height reduced by 35%. The amount of penetration and swelling increased in PaPs using rubber filled with glass bubbles. As the plate thickness increased, the damping feature decreased and the glass balls were activated, and the bullet was stopped.

Fracture toughness is an important index in safety evaluation for materials and structures. Its convenient and accurate characterization has attracted extensive attention. For small specimens, traditional testing methods of fracture toughness are not suitable due to limitations in sample size and shape. In this work, a new formula is proposed to determine the fracture toughness of glasses using scratch tests with a Vickers indenter based on dimensional analysis and finite element analysis. Fracture toughness of glasses could be calculated with elastic modulus, crack depth of scratched materials and normal force applied during the scratch tests. The effects of plastic deformation and interfacial friction between the Vickers indenter and scratched materials are considered, and the crack shape is consistent with experimental observations. The proposed formula is verified by comparing the fracture toughness of soda-lime and borosilicate glasses obtained from scratch tests with those obtained via indentation tests. This work provides an alternative method to determine the fracture toughness of glass materials.

During the thermoplastic forming of TC4 alloy parts, the surface of TC4 alloy billets will be severely oxidized, so it is necessary to prepare anti-oxidation lubrication coating on the surface of billets. By comparing the standard free energy of formation of TiO2 and taking the intermediate value of mass percentage of the corresponding oxide in some literatures, the appropriate oxides such as 44.0% SiO2, 25.0% B2O3, 10.0% Na2O, 7.5% CaO, 6.8% MgO, 1.7% Al2O3 and 5.0% TiO2 were selected to prepare the borosilicate glass powder with high temperature solid-state reaction method. Then, the glass coatings with thickness of 0.15-0.3 mm were prepared on the surface of ϕ17.5 mm × 7.5 mm TC4 alloy cylindrical samples, by dip coating method with the glass powder. It is found that the glass coating has excellent high temperature oxidation resistance by oxidation experiments holding for 2 hours at different temperatures from 500 to 1050 °C. The observations of surface morphology and phase of the glass coating by SEM and XRD found that the glass coating particles with holes between each other, began to melt into amorphous phase at 650 °C. With the increase of temperature, especially above 850 °C, the glass coating gradually melted into a compact film composed of CaMgSi2O6 and a small amount of CaMg(SiO3)2 or Na(AlSi3O8). It can tightly enwrap the substrate and physically isolate oxygen from the furnace gas, so can effectively prevent TC4 billets from oxidation in the range of hot working temperature.

Using electron microscopy and electron probe X-ray fluorescence microanalysis, we have studied chemical and structural changes in the zone of high-temperature contact between 08Cr18Ni10Ti steel and model alkali alkaline earth borosilicate waste form materials for radioactive waste immobilization. The results demonstrate that high-temperature contact with molten waste form materials considerably speeds up corrosion of the metal and that corrosion on the steel surface leads to segregation of corrosion products and the formation of iron chromium spinel and metallic nickel grains under the glass layer. The oxidation product layer has the form of a borosilicate glass-filled porous network. The thickness of this layer depends on the chemical composition of the borosilicate waste form material because the oxidized components of the steel differ in solubility and because the viscosity of the molten waste form material, determining the diffusion rate of the components, varies with composition.

Phosphate glasses have several advantages over traditional silicate-based bioglasses but are inferior in the crucial step of cell attachment to their surface. Here, as a proof of concept, we analyze fibroblast attachment to the phosphate glass surface subjected to basic treatment and silanization. Silicate (S53P4)- and phosphate (Sr50)-based bioactive glasses were either untreated or surface-treated with basic buffer and functionalized with silane. The surface-treated samples were studied as such and after fibronectin was adsorbed on to their surface. With both glass types, surface treatment enhanced fibroblast adhesion and spreading in comparison to the untreated glass. The surface-treated Sr50 glass allowed for cell adhesion, proliferation, and spreading to a similar extent as seen with S53P4 and borosilicate control glasses. Here, we show that surface treatment of bioactive glass can be used to attract cell adhesion factors found in the serum and promote cell–material adhesion, both important for efficient tissue integration. publishedVersion

The effect of additives of P2O5 on the solubility of molybdenum in the amorphous part of glass and on the phase composition of the crystallized part of the highly alkaline glasses of the Li2O–(Na2O–K2O)–B2O3-SiO2 system was studied. The comparison of the phase composition of samples with or without phosphorus prior and after annealing allowed to determine the change of solubility of molybdenum in the amorphous part of the samples and to evaluate the thermal stability of the synthesized glass-ceramic materials. It was found, that for the compositions without phosphorus and the samples without lithium, when molybdenum is added at the synthesis stage, almost all of the molybdenum is included only in the crystalline molybdates. The study has shown an increase in the solubility of molybdenum only in the structure of lithium-containing glasses with phosphorus.

Low-alkali borosilicate glasses are widely used in electronic packaging applications due to their low dielectric constant, low dielectric loss and excellent matching of thermal expansion coefficient to silicon. This paper presents information about structural, thermal and dielectric investigations of low-alkali borosilicate glass compositions for potential electronic packaging applications. Different bulk borosilicate glass samples were fabricated by conventional melting and quenching technique followed by powder processing. Total alkali oxide content in the composition was kept at 2–3 wt% to achieve high dielectric performance. The glass structure was investigated by Fourier transform infrared spectroscopy. X-ray diffraction analysis was employed to investigate crystallization behavior. Thermal properties were investigated by a heating microscope as well as a push-rod dilatometer. The dielectric properties were investigated by an impedance analyzer at room temperature. The results indicated that the glass structure connectivity has a significant effect on thermal and dielectric properties. Reduced glass structure connectivity due to the lower amount of tetrahedral BO4 units resulted in decreased bulk density, dielectric constant and characteristic temperatures as well as glass transition temperature (Tg). Sample D is a promising candidate for electronic packaging application due to its excellent matching of thermal expansion coefficient (3.3 ppm/°C) to Silicon, relatively low softening point (720 °C) and Tg (450 °C), low dielectric constant (4.07) and low dielectric loss (0.0029).

The fabrication and spectroscopic characterization of varying content of Y3+ doped bismuth titanate borosilicate glasses by the melt quenching technique are described. The nature of glass system composition was established using XRD spectra analysis. The manufactured glasses’ molar volume reduced while their density and refractive index continued to increase. UV transmission, absorption, polarizability, and basicity are all found to be highly sensitive to Y2O3 content. The optical bandgap and Urbach energy have been discussed in detail. It was observed that, as Y2O3 increase, the optical bandgap increases, while Urbach energy decreases. Based on the results of the calculations of molar Refractivity, molar polarization, polarizability, optical basicity and dispersion, the fabricated glasses are thought to be very semi-covalent. Metallization of the present glasses are increased.

Spray pyrolytic deposition (SPD) of titania films on borosilicate glass substrates has been carried out using oxime-modified titanium(IV) isopropoxide, [Ti(OiPr)2{ONC(CH3)2}2]. Thermal study of the...

The International Simple Glass (ISG) spherical particles were prepared by Ar–H2 radio-frequency (RF) plasma, the effect of experimental parameters on the volatilization and size distribution of spherical particles was studied. The results show that the spherical powders can be obtained by RF plasma. The spheroidized powders (112 μm) have a smaller diameter than starting particles (124 μm). The high spheroidization (98%) was achieved under low flow rate of carry gas and low feed rate. In addition, the volatilization of B2O3 and Na2O are 23.48% and 56.36%, respectively. The higher feed rate and flow rate of carry gas, the lower volatilization of B2O3 and Na2O and well-spheroidization rate. Meanwhile, the particle surface is not completely smooth at low flow rate of carry gas. The distribution of elements was studied by Electro-probe Microanalyzer (EPMA), which shows the distribution of element is nearly homogeneous that provides a possibility for subsequent research.

Understanding the impact of bismuth cations on the optical properties of borosilicate glass is significant for manipulating borate glass applications. In this paper, the influence of bismuth cations on both structural and optical properties of borosilicate glass doped with NiO was investigated. Different glass samples, containing different amounts of Bi2O3 and a constant amount of NiO, were prepared and studied. Infrared (IR) analysis was carried out to study the internal structure within the investigated glass samples. Optical absorption studies were performed to investigate the impact of Bi2O3 content on optical properties of the BiBaNiB-glasses. Astonishingly, with Bi2O3 addition, an absorption band at 380 nm has appeared. Moreover, this band is overlapped with the Urbach edge; which regularly produced an artificial edge-like feature at ~450 nm. A detailed deconvolution protocol has been implemented for an appropriate understanding of these spectra and unraveling the hidden Urbach edge. Optical band gap energy, linear and nonlinear refractive index for each BiBaNiB sample were calculated. Furthermore, the metallization criterion was calculated to examine the metallic or insulating nature of the BiBaNiB-glasses. The values of the nonlinear third-order susceptibility and nonlinear refractive index were increased with Bi2O3 doping. The BiBaNiB-glasses exhibited outstanding stability and optical band gap than the pristine glass sample, which makes it possible for practical applications.

It is fundamentally important to investigate the interfacial friction between softened glass and rigid molds for controlling the product quality in glass hot forming techniques. However, the underlying mechanism has not been fully understood in terms of the contribution of viscous dissipation to the viscoelastic friction of softened glass. In this paper, a dry rotary sliding scheme using the ball-on-disc pair is employed to investigate the high-temperature friction characteristics of a typical borosilicate crown glass N-BK7 from 500 °C to 660 °C . Experimental results show that the friction coefficients in the steady stage remarkably increase with the applied temperatures. For softened glass, friction could originate from adhesion, ploughing and dissipation. Furthermore, with careful estimations on both the scratch deformation frequency and the induced flash temperature during sliding, the increase in friction coefficient with temperature is well correlated with the loss modulus ratio, which presents the viscous energy dissipation by macroscale ploughing. Additionally, the friction coefficients at 500 mm/s are slightly larger than those at 250 mm/s, because the effect of more frictional heat prevails. Lastly, the influences of temperature and frequency shifting on the loss modulus ratio are summarized to explain the experimental evolution of friction coefficient. It is confirmed for N-BK7 glass that the dependences of friction coefficients on temperature and sliding velocity, also follow the classical superposition master curve of viscoelastic friction.

Direct laser ablation allows high-quality processing, precision, and cutting of complex shapes. Unfortunately, this technology is usually not considered as the primary candidate for cutting and milling of glasses due to low processing speeds. Thus, laser-based rear side drilling and crack generation techniques are chosen instead. However, we report on the milling and cutting of borosilicate glass plates with high average power and high pulse repetition rate picosecond laser. We optimised laser processing parameters for the efficient direct material ablation and employed water-assisted ablation to improve the ablation efficiency and the cutting speed of borosilicate glasses. The laser process was realised through a thin flowing water film, which was formed by spraying water mist on the surface of the workpiece. Firstly, we characterised thin water film parameters, such as film thickness, flow velocity, and defined a working area with constant processing conditions. Next, we optimised laser processing parameters for both processing environments: ablation through the thin water film and in air. Under optimal parameters, ablation through the thin water film was much more effective, increasing the cutting speed of 420 μm thick glass plates nearly ten times – from 0.52 to 5 mm/s. Furthermore, the morphology of the cuts was improved as well: cut wall roughness and edge chipping were reduced, spatter deposition was avoided in the vicinity of the cut. We investigated the milling of 130 to 1700 μm wide and 50 to 500 μm deep grooves with a maximum depth-to-width ratio of 3.8. Findings revealed that the ablation efficiency increase provided by the water layer did not depend on the depth or the width of the groove and remained constant. Therefore, it became possible to predict the ablation efficiency through the thin water film by knowing the ablation efficiency in air and an absolute ablation efficiency difference between two processing environments.

The mid-spatial frequency error and high-spatial frequency error on the optical glass component surface limit the development of high-power laser devices. By heat-treatment in wet atmosphere, the surface can be smoothed spontaneously under the action of capillary force, which is positive to improve the quality of optical components. In this paper, the finite element simulation model of the glass surface smoothing process is established based on the level-set method. The factors affecting the smoothing process, such as morphology wavelength and viscosity, are analyzed by simulation. A series of surface smoothing heat-treatment experiments for borosilicate glass were carried out to verify the effectiveness of improvement on surface quality through heat-treatment. Finally, the reasons for the discrepancy between theory and experiment are investigated through the simulation, and the effects of wavelength and the water content in the material are further investigated.

Borosilicate glass has potential application in the vitrification of high-level waste; therefore, its radiation durability attracts extensive attention. Borosilicate glass samples were irradiated w...