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:In this study, Ag3Sn nanoparticles were synthesized using the redox method and incorporated into SAC305 solder at varymg mass ratios (0, 0. 1 %,0.15%,0.2%)to investigate their impact on the microstructure, wettabihty, and rehabihty of the solder. The physical phase and morphology of the Ag3Sn nanoparticles were characterized by X-ray diffractometer and scanning e!ectron microscope, whUe the microstructure of the solder jonis was observed using a metallograplic microscope. Subsequently, the solder jonis were aged at 150 C for different durations(0, 50, 100, 150, 200 h), and the interfacaal intermetalic compound (IMC) layer thickness was measured usng Image J software to caiculate the growth coefticienr. Resuits indicate that the addition of an appropriate amount ofAg3Sn nanoparticles to SAC305 solder enhances wettabiiity, refines the microstructure, and inhibits IMC layer growth. As aging progresses, the Cu6Sn5 nntermetanic compound layer transitions from scalloped to pknar, accompaned by the appearance of the Cu3Sn nntermetanic compound aye. The optimal performance was observed with the addition of 0. 15 w. % Ag3Sn nanopartides to SAC305 solder, r esulting n improved wettabiity(spreading area of 167. 447 mm2), minimal growth coefficient(0. 04), and enhanced microstructural refinement [ABSTRACT FROM AUTHOR]

Cu6Sn5-xAg alloys (x = 0, 3, 6; %, mass fraction) were synthesized using Ag as a dopant through a high-temperature melting technique. The microstructure of the alloy was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and other equipment, while the hardness of the alloy was measured to investigate the impact of Ag addition on the structure and microstructure of the Cu6Sn5 intermetallic compound. This study explored the influence of varying Ag contents on the properties of Cu6Sn5 intermetallic compounds, with calculations based on first principles revealing the mechanical properties and density of states of η′-Cu6Sn5 and its Ag-doped systems. The results indicated that Cu6Sn5-xAg alloys predominantly existed in three distinct forms, all exhibiting large masses without any impurities or precipitates. First-principle calculations demonstrated that Ag substitution in certain sites suppressed the anisotropy of the Young's modulus of Cu6Sn5, particularly in the Cu1, Cu3, Sn1, and Sn3 positions, while the effect was less significant at the Cu2, Cu4, and Sn2 sites. The introduction of Ag through doping enhanced the covalent bonding within the η′-Cu6Sn5 structure, promoting the formation of a stable (Cu, Ag)6Sn5 structure. [ABSTRACT FROM AUTHOR]

This study reports magnetic graphene oxide composite microspheres (MGO) were firstly synthesized via one step miniemulsion polymerization. α-FeOOH rods were then loaded onto MGO via a facile hydrothermal method to prepare α-FeOOH@MGO, which was served as the photocatalyst for the Fenton reaction. Subsequently, the properties of the resulting α-FeOOH@MGO were characterized by FT-IR, XRD, SEM, VSM and UV-vis DRS analysis methods. The influence of various parameters was investigated, such as dye type, dye concentration, H2O2 dosage, catalysts dosage and pH of MO solution during heterogeneous photo-Fenton processes. Under visible light irradiation, the degradation rate of MO, MB and CR could reach 99.96%, 98.47% and 99.97% in 40 min, respectively. Six cycle experiments confirmed that the α-FeOOH@MGO possessed a satisfied stability and recycling ability. In addition, the photocatalytic reaction mechanism was also revealed by the Mott-Schottky plot, band structure and trapping experiments of active species. [ABSTRACT FROM AUTHOR]

In this paper, Ag3Sn nanoparticles were prepared by chemical method and added into SAC305 solder in different proportions to explore the effects of the Ag3Sn on the wettability, melting performance, metallographic structure, and mechanical property of the solder. The results show that a small amount of Ag3Sn nanoparticles were able to reduce the wetting time, increase the maximum wetting force, and expand the spreading area. The melting performance was also improved. Ag3Sn nanoparticles were also found to significantly refine the solder structure in the metallographical. The best comprehensive performance was achieved with the addition of 0.5% Ag3Sn nanoparticles. These Ag3Sn nanoparticles effectively improved the morphology of the IMC at the interface and effectively reduced the thickness of the IMC layer. The addition of nano Ag3Sn increased the diffusion activation energy and stabilized the interface. Moreover, the growth of the IMC layer was inhibited by 0.5% Ag3Sn, as indicated by aging results. The addition of Ag3Sn nanoparticles increases the tensile strength and Vickers hardness of the solder joint. When the amount of Ag3Sn nanoparticles was 0.5 wt%, the tensile strength reached the maximum of 17.45 MPa. The microhardness value of the solder is greatly increased, which reaches 311 HV. Finite element simulation showed that the service life of the solder was prolonged by adding the appropriate amount of Ag3Sn nanoparticles. The paper demonstrates a method of "nano" solder paste preparation. Results show that the addition of Ag3Sn nanoparticles plays an important role in the interfacial reaction and mechanical properties between the SAC solder and Cu substrate. [ABSTRACT FROM AUTHOR]

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This study investigated the influence of codoping with Ge and GeO2 on the nonlinear coefficient α and the breakdown voltage EB of TiO2-Nb2O5-SrCO3 varistor ceramics. Ge-GeO2 codoping notably changed the microstructure of the TiO2-Nb2O5-SrCO3 ceramics, increased α, and decreased EB. When the doping contents of Nb2O5 and SrCO3 were 0.1 and 0.2 mol%, respectively, the optimum doping content of 0.25 mol% Ge and 0.75 mol% GeO2 exhibited high α (11.6), low EB (13.8 V/mm), and high grain-boundary barrier ΦB (0.96 eV). These results are superior to previous findings. In addition, Ge and GeO2, which function as sintering aids, reduced the sintering temperature caused by the low melting point. The optimal sintering temperature was 1260°C for the TiO2-Nb2O5-Sr CO3 ceramics doped with Ge and GeO2. [ABSTRACT FROM AUTHOR]

This study investigated the effect of elemental crystal Ge or/and GeO 2 doping on the microstructure and varistor properties of TiO 2 –Ta 2 O 5 –CaCO 3 varistor ceramics, which were prepared via the traditional ball milling–molding–sintering process. X-ray diffraction, scanning electron microscopy, scanning transmission electron microscopy-energy dispersive X-ray spectroscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy demonstrated that co-doping with Ge and GeO 2 changed the microstructure of TiO 2 –Ta 2 O 5 –CaCO 3 ceramics, thereby increasing the nonlinear coefficient and decreasing the breakdown voltage. The optimum doping concentrations of Ta 2 O 5 , CaCO 3 , Ge, and GeO 2 exhibited the highest nonlinear coefficient (α =14.6), a lower breakdown voltage ( E B =18.7 V mm −1 ), the least leakage current ( J L =10.5 μA cm −2 ), and the highest grain boundary barrier ( Φ B =1.05 eV). In addition, Ge and GeO 2 function as sintering aids, which reduce the sintering temperature because of their low melting points. [ABSTRACT FROM AUTHOR]