Key Engineering Materials Vol. 509

Abstract: Forming Limit Diagram of AZ31 magnesium alloy in different forming methods was researched in this paper. Experiment equipment and processes were improved successfully. Some tests and experiments (including tensile test, punch test and electromagnetic forming experiment) of AZ31 magnesium alloy sheet were done. Forming Limit Diagram of electromagnetic forming was established successfully. It could promote the application of magnesium alloy sheet in electromagnetic forming. Forming Limit Diagram of static forming was established successfully. It was very useful for the application of magnesium alloy sheet in other forming methods. The difference between these Forming Limit Diagram showed that electromagnetic forming obviously improve forming ability of the magnesium alloy sheet.

Abstract: Three-dimensionally (3D) ordered macroporous ZnO film was fabricated on a glass slide by layer-by-layer depositing and hydrolysis of Zn(CH₃COO)₂ using 3D-ordered latex film as template followed by calcination at 450 °C for 2 h to remove the organic template. The as-prepared 3D-ordered macroporous ZnO film was characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), diffusive reflectance UV-visible absorption spectra (DRUV-VIS), photoluminescence (PL), and photoelectrochemical measurement. Its photocatalytic activity was evaluated by the photocatalytic degradation of crystal violet (CV) aqueous solution at ambient temperature under the irradiation of simulated solar light. It was found that the 3D-ordered ZnO film exhibits efficient photocatalytic activity for photodegradation of CV under the irradiation of simulated solar light.

Abstract: In this paper, the distribution of magnetic forces of uniform pressure coil and the electromagnetic shaping with die of aluminum alloy 1060 surface parts will be researched using the finite element method. The results show that: Uniform pressure coil can produce a uniform magnetic pressure on the sheet; The springback after electromagnetic aimed stamping is smaller than the springback after normal stamping; Before achieving the best results, with the discharge energy increases, springback will be smaller; with greater punch and die clearance, greater energy will be needed to achieve the best effect; Too large discharge energy will lead sheet bounce after punch, springback increases.

Abstract: Transparent oxide glass is the ideal luminescent host materials used in luminescence, optical communication, fiber optic amplifiers and other areas in the future as its stable physical and chemical properties, high rare-earth ion solubility and easy forming, etc. In this paper, SiO2-TiO2-SrO-SrF2-Sm2O3 glasses with different content of fluorine were prepared by the melting-quenching method. Influence of fluorine on the structure and luminescence properties of the glass were studied by Fourier transform infrared spectroscopy, X-ray fluorescence spectrometer, UV-visible spectrophotometer and fluorescence spectrometer. The results show that there is a new peak at 930 cm-1 in IR spectra because of fluorine, and the intensity of the peak increases with the increases of fluorine content. The glass absorbed ultraviolet rays strongly, and transmitted light well in visible spectra region. The strongest absorption peak is around 403 nm. Fluorine content doesn’t affect the positions and shapes of peaks in excitation and emission spectra, but the luminescent intensity increases with the increase of fluorine content.

Abstract: ZnO:Al thin films were deposited on low-iron glass substrates (size: 1100×1400 mm2 ) in an in-line sputtering system, using ZnO:Al ceramic targets. The initially smooth films exhibit high transparencies (T≥85% for visible light) and excellent electrical properties (carrier concentration N=3.810×1020cm-3, mobility μ=20.47 cm2/V•s). The films, etched by diluted HCl for different time, appear roughness morphology with suitable angles and crater structure, used for controlling the light scattering properties of the textured ZnO:Al films. Moreover, the electrical properties are not affected by the etching process. Thus, it is possible to optimize separately the electro-optical and light trapping properties. The textured ZnO:Al films (haze 21.2%, 550 nm) were used as front contacts for amorphous silicon thin film solar cells prepared by PECVD, 6.5% conversion efficiency were obtained.

Abstract: Lminescent glass is widely used in building, energy saving, emergency lighting and art crafts; The energy consumption for global illumination is rising year by year, and the energy consumption has become a global problem; the research of luminescent glass is important for the developing of the energy-saving light. In this paper, the glass of the P2O5-ZnO-SiO2 system was used as matrix material, the matrix material was doped with yttrium aluminum garnet crystals containing Ce (YAG:Ce phosphors) and then were sintered for the preparation of the luminescent glass. Using X-ray diffraction and fluorescence spectrometer, the effects of the doping quantity, sintering temperature and sintering time on luminescent properties were studied. The results show that, for the P2O5-ZnO-SiO2 glass, excitation at 340 nm and 468 nm, produced emission at 544 nm; Doping quantity, sintering temperature and sintering time affect intensity of emission peak, but do not affect the position of emission peak.

Abstract: The computer aid simulation of optical properties of thin films has been used to optimize SiO2/TiO2/SiO2 multilayer films to obtain high transparent films in this paper. The maximum transmittance at the visible light wavelength range is proper criteria for optical films optimizing design. The effect of design parameters (film thickness and refractive index) on optical properties of SiO2/TiO2/SiO2 multilayer films were also discussed in detail. According to the result of optimization, high quality SiO2/TiO2/SiO2 multilayer film with a maximum of > 99% at visible light wavelength range can be achieved on the glass.

Abstract: Eu₂O₃ doped boron silicate glass appearing phase separation have been prepared and characterized. The heat treatment temperature was determined by DTA, the microstructure and optical properties of the glass were studied by SEM and fluorescence spectra. The adding of Eu₂O₃ restrained the phase separation and crystallization of the glass. Eu ions exist in the glass samples as the Eu³⁺ ions, rather than the Eu²⁺ ions. As the heat treatment temperature increases, the phase separation region increased gradually, and the luminescent intensity increases.

Abstract: In this paper, optical, the chemistry stability, and glass transformation, softening temperature were studied on Bi2O3-SiO2-ZnO-B2O3 system glass doped with 2wt.%、4wt.%、6wt.% and 8wt.%TiO2. The results showed that glass surface has no stripes and defects with transmittance between 20%-50%. Moreover, with the increasing of Ti content, the results of the experiments indicated that the metal oxides TiO2 could enhance the glass chemical stability most clearly, and regulate the glass transformation temperature.

Abstract: Li₂O-Al₂O₃(La₂O₃)-TiO₂-P₂O₅ glass-ceramics were fabricated through heat-treatment of the original glass. The differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical workstation were employed to study the structural, morphology and electrical properties of the samples heat-treated at different temperatures. The results showed that: the glass-ceramics consist of the dominating LiTi₂(PO₄)₃ phases, trifle AlPO₄, TiO₂ and unknown phases. With the heat-treatment temperature increasing from 700 °C to 1100 °C, the structure of glass-ceramic become denser and grain grew, lithium ion conductivity increased quickly and subsequent cut down gradually. While the specimen was obtained by crystallization at 900 °C for 12 h, the total conductivity of glass-ceramic material come up to the maximum (5.85 ×10^-4 S•cm^-1) at 25 °C. This inorganic solid electrolyte has a potential application in lithium batteries or other devices.