ZnO B2O3 SiO2 Research Articles

Key phase diagram experiments and thermodynamic modeling of the ZnO‒B2O3, ZnO‒SiO2, and ZnO‒B2O3‒SiO2 systems

AbstractThermodynamic modeling of binary ZnO‒B2O3 and ZnO‒SiO2 systems and ternary ZnO‒B2O3‒SiO2 system were carried out based on the critical evaluation and optimization of all available phase diagram and thermodynamic property data using the CALculation of PHAse Diagram (CALPHAD) method. To resolve the inconsistency among the available phase diagram data in ternary ZnO‒B2O3‒SiO2 system, key phase diagram experiment was carried out using classical quenching method followed by electron probe micro‐analysis and X‐ray diffraction phase determination. The liquid oxide solution was described using the modified quasichemical model accounting for a short‐range ordering behavior in molten oxide solution. Thermodynamic models with optimized model parameters were used to predict the phase diagram and thermodynamic properties of the ternary systems.

Structural, thermo-mechanical, optical and gamma-ray shielding properties of lead-free BaO–ZnO–B2O3–SiO2 and lead-based PbO–Bi2O3–K2O–SiO2 glasses

Lead-free BaO–ZnO–B2O3–SiO2 glass (BZBS) and lead-based PbO–Bi2O3–K2O–SiO2 glass (LS) were synthesized by melt quench technique. Glass samples were irradiated using 60Co gamma source up to 50 kGy dose to study the changes in structural, thermo-mechanical, optical and gamma ray shielding properties. Measured density values of both the glasses were greater than 4.0 g/cc. X Ray Diffraction (XRD) studies confirmed amorphous nature of prepared glasses before and after gamma irradiation. The structural changes induced by gamma irradiation were also investigated using Raman, Positron annihilation lifetime spectroscopy (PALS) and Electron Paramagnetic Resonance (EPR) spectroscopy. PALS data revealed increase in free volume/voids after irradiation. Defect studies carried using EPR spectroscopy confirmed formation of electron trap centre in BZBS glass, whereas in LS glass in addition to the electron trap centers, non-bridging oxygen hole centers (NBOHC) and peroxy radical defects were also observed. Investigations on thermo-mechanical properties demonstrated higher glass transition temperature (Tg), hardness and modulus of elasticity values for BZBS glass as compared to the LS glass, which were found to be decreased after irradiation because of radiation induced defects. Visible transparency and band gap for BZBS glass were found to be higher than that in LS glass. After irradiation, colour change, reduction in transparency as well as band gap, and red shift in absorption edge were observed due to the formation of defects in both the glasses. The values of radiation induced absorption (α) at three different visible wavelengths have been determined for 50 kGy dose using UV–Vis transmission data. Analysis of refractive index data showed around 12 % reflection losses for both the glasses. Annealing of irradiated samples using UV light source showed significant improvement in transparency. Linear attenuation coefficient (LAC) was calculated using XCOM program and experimentally measured using 60Co 1.33 MeV gamma ray. Linear attenuation coefficient of BZBS glass was around 0.20 cm−1 whereas for LS glass value was 0.24 cm−1. Half value layer thickness of prepared glasses was also compared with available standard materials and it was found that prepared glasses may be suitable for shielding of high energy gamma rays.

Accelerating densification of the terminal electrode with improved adhesion by sodium ions doping for MLCC copper paste

Glass frits effectively facilitate the sintering densification to produce high-density terminal electrodes, crucial for achieving high reliability of MLCC (Multilayer Ceramic Capacitors) devices. However, manufacturing terminal electrodes with high density and strong adhesion under low-temperature sintering condition still has enormous challenges. Herein, Na2O–BaO–ZnO–B2O3–SiO2 glass has been fabricated for low temperature sintering copper paste. We demonstrate that the densification degree and adhesion strength of the terminal electrode can be notably optimized by adjusting the Na2O content in the glass frit. The doping of Na+ in glass effectively improves the wettability of the melt on the copper substrate and the surface tension of the glass melt, enhancing the capillary force in the liquid phase sintering process. The rate of electrode densification is accelerated by the increase in capillary force, thus reducing the sheet resistance of copper film from 4.52 to 4.30 mΩ/□. Furthermore, with the increase in the Na+ content, the work of adhesion between glass and ceramic gradually increases, which effectively enhances the shear strength of the electrode from 19.66 MPa to 29.55 MPa. Our work provides novel insights for the design of glass compositions in the field of terminal paste.

Low‐temperature co‐fired ceramic application of SmTaO4 and YTaO4 with ZnO‐B2O3‐SiO2 additive

AbstractIn this study, ZnO‐B2O3‐SiO2 (ZBS) glass was employed as a sintering facilitator, enabling low‐temperature sintering of SmTaO4 and YTaO4 ceramics. The influence of varying quantities of ZBS glass on sintering behavior and phase composition was investigated to reveal the low‐temperature sintering mechanism. ZBS glass exhibits favorable wetting behavior on the SmTaO4 and YTaO4 ceramic matrices and dramatically decreases the initial shrinkage temperature of ceramics throughout the sintering process. Composited with 20 wt. % ZBS and sintered at their optimal sintering temperature, the composite ceramics of SmTaO4 and YTaO4 possess favorable microwave dielectric properties: εr = 8.46, Q×f = 15,723 GHz, and τf = –6.68 ppm/°C (at 14.339 GHz), and εr = 4.21, Q×f = 18,939 GHz, and τf = –18.92 ppm/°C (at 15.512 GHz), respectively.

Effect of (Fe0.8Cr0.2)2O3 pigment on the optical properties of ZnO–B2O3–SiO2 glass-based coatings for double-glass photovoltaic modules

Solving technical issues of light pollution, thermal protection, color aesthetics, and weathering resistance for the coating layer used in double-glass photovoltaic modules of a solar panel, new coating materials were produced using ZnO–B2O3–SiO2 glass frit and (Fe0.8Cr0.2)2O3 pigment. In this work, the crystal structure, the microstructure, the distribution of Fe and Cr elements, the diffusion of element Fe, the adhesion and the optical properties of the coatings have been characterized. The surface roughness of the coatings has a more significant alteration when the (Fe0.8Cr0.2)2O3 content is greater than 49 wt%. For the coating doped with 46 wt% (Fe0.8Cr0.2)2O3, the amount of Fe diffused into the glassy phase gradually increases from 0.17 wt% to 0.54 wt% as the heat-treatment temperature increased from 650 °C to 720 °C. The effects of (Fe0.8Cr0.2)2O3 pigment content and heat-treatment temperature on the optical properties of coatings were explained mainly from the coatings surface roughness, Fe-redox induced pore formation, Fe-diffusion, and formation of large defects surfaced for the coatings.

Microstructure and dielectric properties of low-temperature sintered MgO-based ceramics at millimeter wave and terahertz frequencies

Low-temperature co-fired ceramics (LTCC) applied in millimeter/microwave and terahertz frequencies (5G/6G) have attracted a lot of attention recently. In this study, MgO-based dielectric ceramics were successfully sintered at 950∘C with the sintering aids: x wt.% of LiF fluoride ([Formula: see text], 4, 6, 8, 10) and 0.5[Formula: see text]wt.% of BBSZ (Bi2O3–B2O3–SiO2–ZnO) glass. BBSZ glass was introduced as another sintering aid to facilitate the sintering and densification. Crystalline structure and micro-morphology were investigated and analyzed. Dielectric properties ([Formula: see text], [Formula: see text], [Formula: see text]) at millimeter/microwave and terahertz wave frequencies were also studied. The ionic characteristics of Mg–O bond ([Formula: see text]), the lattice energy (U) and the bond energy (E) were calculated and analyzed. It is suggested that the optimal [Formula: see text], where [Formula: see text], [Formula: see text][Formula: see text]GHz (@12[Formula: see text]GHz) and [Formula: see text][Formula: see text]ppm/∘C at millimeter/microwave range. When the frequency was up to terahertz (1.0[Formula: see text]THz), the [Formula: see text] values were 8.8–9.35 and the tan[Formula: see text] were [Formula: see text]–[Formula: see text]. The experimental results indicated that the low-temperature sintered MgO-based ceramics have potential for millimeter/microwave and terahertz communication applications.

Gamma radiation shielding properties of (x)Bi2O3–(0.5 – x)ZnO–0.2B2O3–0.3SiO2 glass system

Abstract Lead (Pb)-based materials are very effective in radiation shielding due to their high density of Pb. However, they pose health risks to humans because of the toxicity of lead. As a result, the investigation of radiation shielding properties of various lead-free glass materials has drawn a lot of attention from researchers. In this work, the γ radiation competence of the Bi2O3–ZnO–B2O3–SiO2 glass network was investigated, for the first time in the 0.015–15 MeV energy range, using Phy-X/PSD and XCOM software systems. The results showed that 45Bi2O3–5ZnO–20B2O3–30SiO2 glass sample has the highest linear attenuation coefficient, mass attenuation coefficient, and effective atomic number, and it has the lowest half-value layer, tenth-value layer, and mean-free path. Therefore, 45Bi2O3–5ZnO–20B2O3–30SiO sample is more effective on γ ray shielding than 10Bi2O3–40ZnO–20B2O3–30SiO, 20Bi2O3–30ZnO–20B2O3–30SiO, 30Bi2O3–20ZnO–20B2O3–30SiO, and 40Bi2O3–10ZnO–20B2O3–30SiO samples. The comparison of the results with the literature also revealed that the 45Bi2O3–5ZnO–20B2O3–30SiO glass sample is even more effective than some of Bi2O3-based glass systems, which were recently developed in the literature, by at least a factor of 2.

Low-temperature sintering and phase component modulation of 0.95MgTiO3–0.05CaTiO3 microwave dielectric ceramics

This study prepared glass doped 0.95MgTiO3–0.05CaTiO3 (95MCT) ceramics with excellent microwave dielectric properties via phase constituent regulation. Based on XRD and semi-quantitative analysis, it is found that the types of glass, addition amounts of glass, and sintering method can introduce different phase compositions. With the aid of the low softening point for glass materials and the liquid phase sintering mechanism, the 95MCT ceramics can be densified at a relatively low temperature. Meanwhile, based on the mixture rule, adjusting the proportion of each phase structure by altering the sintering method, the optimum temperature (1200 °C) for 95MCT ceramics is reduced by about 200 °C without deteriorating performance. Typically, the 95MCT ceramic doped with 1 wt % ZnO–B2O3–SiO2 glass demonstrates excellent microwave dielectric properties: εr = 18.3, Q × f = 50824 GHz (@7.9 GHz).

Sintering behavior, microstructure and dielectric performance of Al2O3 ceramic with addition of new Bi2O3‒B2O3‒SiO2‒ZnO glass

Sintering behavior, microstructure and dielectric performance of Al2O3 ceramic with addition of new Bi2O3‒B2O3‒SiO2‒ZnO glass

Effect of properties and crystallization behavior of BaO–ZnO–B2O3–SiO2 glass on the electrical conductivity of Cu paste

AbstractThe extensive application of multilayer ceramic capacitors provides an attractive development for terminal electrode pastes. However, the growing requirement for advanced glass materials used in terminal electrode pastes is substantiated. Therefore, to advance the development of electrode pastes, better development and deeper exploration of glass powder are required. Here, a series of BaO–ZnO–B2O3–SiO2 (BZBS) glasses were prepared by melt‐quenching technique, which are used to investigate the effect of the introduction of BaO on structure and properties of the ZnO–B2O3–SiO2 (ZBS) glass. With the introduction of BaO, the relative amount of [BO4] was much less, which made the glass network structure loosen, decreased the glass transition temperature (Tg) and increased the coefficient of thermal expansion of the glass. The decreasing contact angle was observed on the surface of a barium titanate (BaTiO3) substrate. When the BaO content was around 3–7 mol%, the stability of ZBS glass frit could be strengthened by inhibiting the precipitation of Zn2SiO4 crystal. In addition, to further characterize the effect of glass on terminal electrode paste, BZBS glass powder was adopted to prepare copper electrode paste, which was printed on the BaTiO3 substrate and subsequently fired at 800°C for 10 min. With the related copper paste containing ZBS glass doped with 7 mol% BaO, the optimum value of acid resistance and sheet resistance (1.99 mΩ) were exhibited, at which the coated copper paste formed a dense conducting layer.

Synthesis and magnetic properties of low-temperature sintered, LMZBS glass-doped dense NiCuZn ferrites

Doping has been used to control the microstructure and optimize the magnetic properties of low-temperature co-fired ceramics. In this study, the growth mechanism of (Ni0.2Cu0.2Zn0.6O)1.03(Fe2O3)0.97 ferrites doped with Li2CO3–MgO–ZnO–B2O3–SiO2 (LMZBS) glass and sintered at 920 °C was investigated. X-ray diffraction showed that all the samples had a single-crystalline phase structure, with no secondary phases generated. Scanning electron microscopy showed that LMZBS glass exhibited a dense microstructure with a reduced number of pores. The glass promoted a compact ferrite crystal structure formation under low-temperature conditions. The magnetic properties of the ferrites were also improved considerably. Specifically, the permeability of the NiCuZn samples was improved from 320.75 to 547.01 at 0.001 GHz. The sample with 0.25 wt% LMZBS exhibited a saturation magnetization of 4066.973 Gauss and high saturation flux density (Bs = 278.2 mT) and remanence (Br = 151.2 mT). Overall, the LMZBS glass promoted NiCuZn ferrites with uniform and compact microstructure and excellent magnetic properties.

Effect of TiO2 on the sintering temperature and dielectric properties of Li2O–MgO–ZnO–B2O3–SiO2 ceramic composites for LTCC applications

Effect of TiO2 on the sintering temperature and dielectric properties of Li2O–MgO–ZnO–B2O3–SiO2 ceramic composites for LTCC applications

Dielectric Breakdown Strength and Energy Storage Density of CCTO-ZBS Electroceramic

The effect of ZnO-B2O3-SiO2 (ZBS) glass additives to the microstructure and electrical properties of CaCu3Ti4Oi2 (CCTO) electroceramic has been successfully investigated in this research. CCTO and ZBS glass additives were prepared via solid state reaction and melt quench techniques, respectively. Raw materials of both CCTO and ZBS were wet mixed separately for 24 hours, dried overnight and the CCTO powder was calcined at 900 °C for 12 hours using an electrical carbolite furnace. After that, the ZBS powder was melted at 1400 °C for 2 hours using an elevator hearth furnace. The ZBS glass was grinded to form fine powder. Different weight percentages (0, 1, 3, 5, 7 and 10 wt%) of ZBS glass powder were added into CCTO (CCTO-ZBS powders), then the powders were wet mixed for 24 hours. The CCTO-ZBS mixtures were dried overnight, compacted at 300 MPa using hydraulic pressure of 6 to 9 mm diameter and 1 to 2 mm thickness (for dielectric properties test) and at 200 MPa of 50 mm diameter and 3 mm thickness (for dielectric breakdown strength test), then sintered at 1040 °C for 10 hours using an electrical carbolite furnace. The addition of a small amount of ZBS glass about 1 wt% was able to increase the dielectric constants (33.99%) and reduce the dielectric loss (5.14%) of CCTO measured at 1 MHz. This addition has also increased the relative density to the maximum value (95.90%), helped the formation of single phase of CCTO, increased the grain size (0.35%) and reduced the porosity as compared to pure CCTO. Meanwhile the dielectric breakdown strength (58.0%) and volumetric energy storage density (80.9%) has also improved with 7 wt% of ZBS glass addition.

Sintering behavior and properties of Li2O–MgO–ZnO–B2O3–SiO2 ceramic composites for applications in low temperature co-fired ceramic (LTCC) technologies

Herein, the Li2O–MgO–ZnO–B2O3–SiO2 (LMZBS) ceramic with low sintering temperatures were prepared via the traditional solid-state method, and the Mg2SiO4/LMZBS ceramic composite was prepared by adding Mg2SiO4 ceramic, and the results showed that the properties of LMZBS ceramic was improved upon addition of Mg2SiO4 ceramic. The sinterability, microstructure, dielectric properties, mechanical properties and coefficient of thermal expansion (CTE) of composite were determined. The crystal structure was determined using X-ray diffraction, and Mg2SiO4, Mg3B2O6, Mg2B2O5 were the main phase. The 20 wt% Mg2SiO4 ceramic sintered at 900 °C exhibited superior performance: $${\varepsilon }_{\rm{r}}$$ of 6.97, Q value of 1732 at 10 GHz and flexural strength of 206 MPa, and CTE value of 10.06 ppm/°C. The composite was also found to match well with the Ag electrode in an investigational study. These properties have made the Mg2SiO4/LMZBS ceramic composite great candidates in low-temperature co-fired ceramics technology.

Evolutionary mechanism of YBO3 whisker and its effect on the properties of YIG ferrite joint brazed by Bi2O3–B2O3–SiO2–ZnO glass

The Bi2O3–B2O3–SiO2–ZnO glass braze was used to bond the Yttrium iron garnet (YIG) ferrite. The (i) microstructure evolution and (ii) mechanical and dielectric properties of YIG/YIG joints were investigated. The results show that the bonding of YIG ferrite with Bi2O3–B2O3–SiO2–ZnO glass braze was effective at brazing temperature. There were nearly free of defects. At the YIG/glass interface, gray YBO3 whiskers, gray layered YBO3, and black block Fe2O3 phases were observed due to the reaction of the glass braze and YIG ferrite. As the brazing temperature or holding time increased, the gray layered YBO3 phase turned into YBO3 whisker gradually. This is because the B–O bonds of [B3O9] ring in the unit cell of the layered YBO3 are broken and evaluated to [BO4] in the cell of YBO3 whisker. The shear strength reached a maximum of 65 MPa for the joint brazed at 725 °C because of the enhancement effect of YBO3 whisker and Fe2O3 phases. The relative dielectric constant of the joint brazed at 700 °C was about 16, which was close to that of YIG ferrite. Moreover, the dielectric loss of this joint was about 0.005.

Influence of Li2O–MgO–ZnO–B2O3–SiO2 glass doping on the microwave dielectric properties and sintering temperature of Li3Mg2NbO6 ceramics

Li3Mg2NbO6 + x wt% Li2O–MgO–ZnO–B2O3–SiO2 (LMZBS, x = 2, 4, 6, 8, 10) microwave dielectric ceramics with the rock-salt structure were primarily investigated by the traditional solid-state method. The microstructures, microwave dielectric properties, and sintering characteristics were studied systematically according to the doping concentration and sintering temperature. It could be seen that the LMZBS glass effectively lower the sintering temperature of Li3Mg2NbO6 ceramics from 1250 to 925 °C with microwave dielectric properties changing as a function of the amounts of the LMZBS glass. The experimental results showed that 4 wt% LMZBS glass enabled Li3Mg2NbO6 ceramics sintered at 925 °C for 4 h to have excellent microwave dielectric properties: er = 16.02, Q × f = 56,455 GHz, τf = − 18.81 ppm/°C. Therefore, Li3Mg2NbO6 ceramics doped with LMZBS glass meet the requirements of low-temperature co-fired ceramics.

Effect of LMZBS glass on the microstructure and microwave dielectric properties of monocelsian ceramics

BaAl2Si2O8–Li2O–MgO–ZnO–B2O3–SiO2 (BAS-LMZBS) glass ceramics were prepared through the solid-state route. The phase transformation, microstructure, bulk density and microwave dielectric properties of (1-x)BaAl2Si2O8-xLMZBS(x = 0.1–0.4) the glass ceramics were examined. The effects of the LMZBS additive as a mineralizer on the hexagonal-to-monoclinic transformation were investigated by X-ray diffraction and scanning electron microscope. All of the hexagonal phases were converted into monoclinic phases when x = 0.1, and it was found that LMZBS glass affected the densification of the ceramic samples. Monocelsian was successfully prepared, and its sintering temperature was reduced from above 1400 °C–870 °C by adding LMZBS glass. Excellent microwave dielectric properties (εr = 7.31, Q × f = 48,926 GHz and τƒ = −48 ppm/°C) were obtained at 870 °C. This sample shows great chemical compatibility with Ag electrodes and can be a promising candidate for practical applications of low-temperature, co-fired ceramics.

Microwave dielectric properties of low-temperature-fired MgNb2O6 ceramics for LTCC applications.

MgNb2O6 ceramics doped with (Li2O–MgO–ZnO–B2O3–SiO2) glass were synthesized by the traditional solid phase reaction route. The effects of LMZBS addition on microwave dielectric properties, grain growth, phase composition and morphology of MgNb2O6 ceramics were studied. The SEM results show dense and homogeneous microstructure with grain size of 1.72 μm. Raman spectra and XRD patterns indicate the pure phase MgNb2O6 ceramic. The experimental results show that LMZBS glass can markedly decrease the sintering temperature from 1300 °C to 925 °C. Higher density and lower porosity make ceramics have better dielectric properties. The MgNb2O6 ceramic doped with 1 wt% LMZBS glass sintered at 925 °C for 5 h, possessed excellent dielectric properties: εr = 19.7, Q·f = 67 839 GHz, τf = −41.01 ppm °C−1. Moreover, the favorable chemical compatibility of the MgNb2O6 ceramic with silver electrodes makes it as promising material for low temperature co-fired ceramic (LTCC) applications.

Effect of the melting conditions on the properties of glasses in the system PbO–ZnO–B2O3–SiO2

Effect of the melting conditions on the properties of glasses in the system PbO–ZnO–B2O3–SiO2

Performance model for tempered anti-glare LCD cover glass

A novel manufacturing process for anti-glare (AG) coating is proposed for the LCD cover glass that is purposed to significantly improve the durability of AG film, which is widely implemented in commercial products designed for outdoor use. The proposed coating method is implemented in the screen-printing process, which precedes the glass-tempering process, entails application of ZBS (ZnO-B2O3-SiO2) to the glass surface during the silk screen-printing process, and achieves the desired level of performance through the tempering process. We also implemented the experimental results to establish the primary design parameters and derive the formulae necessary to develop a performance model that can predict the haze, roughness, and transmittance of the cover glass, which are representative specification of cover glass. Experimentation was used to subsequently verify the proposed method and the performance model.