Advanced Materials Research Vol. 898

Abstract: This paper briefly reviews the overseas and domestic research status of the mechanics of hetero film-substrate interface based on molecular dynamics simulation, on this basis building the accurate model of diamond coatings/WC interface and executing the molecular dynamic simulation, exactly measuring the adhesive strength of the diamond coatings/WC interface, finally exploring the influence of interface scales on the adhesive strength of the diamond coatings/WC interface and verifying the feasibility of studying the microscopic structure by molecular dynamics simulation to characterize the mechanical properties of macrostructure, which has important significance for optimizing deposition process of diamond coatings to improve the adhesive strength of the interface.

Abstract: NiCoCrAlY coating with high density was prepared on the surface of the magnesium alloy by cold spraying. Compared with the magnesium alloy prepared by the methods of the semi-continuous casting, the wear resistance and wear mode were analyzed by the experiments. The results showed that, under the dry friction condition, the conditions of the weightlessness of wear of NiCoCrAlY coating were better than that of the magnesium alloy. After the frictional experiment for 20 minutes, the weightlessness of wear of NiCoCrAlY coating was 10mg. Compared with that of the magnesium alloy, the weightlessness of wear was lower than 28%. Consequently, the NiCoCrAlY coating had the capacity of the weightlessness of wear resistance. By the comparisons of the every samples friction morphology, the wear modes of the NiCoCrAlY coating were adhesive wear and abrasive wear. And the wear modes of magnesium alloy were also adhesive wear and abrasive wear with corrosive wear and fatigue wear.

Abstract: In this work, a magnetic polymer electrolyte composed by agarose as polymer matrix, NMP as solvent and NiO/TiO₂ mixed nanoparticles as modifier was investigated and employed in the solid-sate dye-sensitized solar cells (DSSCs). The influence of NiO/TiO₂ mixed nanoparticles on the morphology and ionic conductivity of the polymer electrolyte was studied by SEM and electrochemical impedance spectra. From SEM analysis, the mixing of NiO with TiO₂ nanoparticle in polymer electrolyte leads to smooth surface of the polymer electrolyte films. The polymer electrolyte modified by mixed nanoparticles with NiO: TiO₂ ratio of 1:4 shows the maximum ionic conductivity of 6.64×10^-3 S·cm^-1. From photovoltaic performance study, the increase of NiO: TiO₂ ratio in polymer electrolyte leads to an improvement in light-to-electric conversion efficiency. The optimal photoelectric efficiency is achieved at NiO: TiO₂ ratio of 1: 4. Besides, after treatment under an external magnetic field, the DSSC modified with NiO: TiO₂ ratio of 1: 4 exhibits a better photovoltaic performance than that of DSSC without magnetic field treatment.

Abstract: Highly active titanium modified 3D mesoporous material Ti-TUD-1 with different Si/Ti molar ratios (10, 25, 50 and 100) were synthesized using TEA as a template and TEAOH as an auxiliary template. The Ti-TUD-1 materials were characterized by means of XRD, TEM and UV-vis DRS. The results showed that Ti was successfully incorporated in the framework of TUD-1 by forming Ti-O-Si bonds. The catalytic activities were tested in a high pressure micro reactor using FCC diesel and the results showed that the HDS efficiency of Ti modified TUD-1(Si/Ti=50) was better than TUD-1, as high as 98.15%.

Abstract: In order to improve fatigue life of wheel steel, LF-VD secondary-refining process is done with Al-deoxidation and slag of high basicity, high Al₂O₃ content and low oxidizing property. Inclusion content would be influenced by [Al]_s, [Mg], [Ca] in molten steel. It is found that Al₂O₃ inclusions, which are the products of Al-deoxidation, would react with [Mg], [Ca] in molten steel to transform into CaO-MgO-Al₂O₃ complex inclusions, which is the key for the enhancement of fatigue performance for wheel steel.

Abstract: High conductive and polymer composite has good electrical, mechanical and electrochemical properties which is a scalable, multi-functional composite material. It is widely used in electric vehicles, power storage and military fields. This article treats graphene as the working electrode self-supporting film and prepares the structures of the reduction of graphene-polypyrrole-Sulfonated graphene three-layer composite membrane using Polypyrrole electrochemical deposition method. From the electricity microscope, we can observe that the composite film have a closely structure which improves the electrical conductivity and mechanical properties of highly conductive polymer material. Finally, this paper studies the electrical properties of the composite film by the way of electrical experiment. From the experiment, we can conclude that in the voltage driver of 1V, the composite film has a better driving performance which can reach a rate of 198 / s. Its cycle life is up to 8000 times. This provides a new method for preparation and study of graphene conductive polymer composite.

Abstract: Hot ductility behaviors of HRB600 vanadium-containing steel rebar was study with thermal simulation test and the fracture was observed and analyzed by scanning electron microscope (SEM). The result shows that, the contraction ratio of cross sectional area (Z) in 1050°C - 1300°C was more than 60%, tensile sample showed good ductility; Z in 750°C-1000°C was less than 60%, tensile sample showed brittle, namely third brittle zone. Then third brittle zone should be avoided or minimize stays in the development process of continuous casting and hot rolling. The fracture mode and the morphology of fracture surfaces were different at different temperatures.

Abstract: Isothermal compression test at constant strain rate for Cr-77.5Nb alloy were performed on Gleeble simulator with conditions of deformation temperature from 800 to 1200°C and strain rate from 0.001s^-1 to 0.1s^-1. The influence of deformation parameters including temperature, strain rate and strain related with flow stress during hot deformation were investigated and the constitutive relation of Cr-77.5Nb alloy was established by stepwise regression method. The result of error analysis shows that the constitutive relation established has high accuracy and can well characterize the hot deformation behavior of this alloy.

Abstract: In this paper, a novel yellow-emitting oxynitride phosphor Sr_3-2xSiO_5-6xN_4x: yCe³⁺, yLi⁺ (0 x 0.33, 0.01 y 0.04) has been reported. The XRD patterns illustrate that the partial substitution of (SiN)⁺ for the (SiO)²⁺ is feasible and the major phase of synthesized samples is isostructural with Sr₃SiO₅. Under blue light excitation, the oxynitride phosphor shows a broad emission about 557 nm, contributing to the 4f5d transition. The PL intensities show a blue shift as the increase of nitrogen content (the locations of peaks move from 559 nm to 549 nm).

Abstract: Isocyanate-terminated prepolymer was synthesized by reaction of polyether polyols with toluene diisocynate and was modified by CaO and hydroxyl silicone oil, then solvent-free moisture curable heavy anti corrosion PU coating was prepared. The structure of cured coating was characterized by FTIR spectra and SEM. The mechanical properties, water tolerance, water contact angle of cured coating were analysed. The results showed that the solvent-free moisture curable heavy anti corrosion PU coating had the best combination property with 5% polyether polyols N210, 4% CaO and 4% hydroxyl silicone oil.