Abstract: TiO2-SiO2 double-layer films are prepared on glass substrates by sol-gel method and dip dipping method. The effect of aging time, heat treatment temperature and molar content of TiO2 for the optical properties of the films have been studied on this paper. And on this basis TiO2-SiO2/SiO2 double-layer films have been prepared as well as the transmittances in the visible range of it have been studied. The results of this paper show that the transmittances of TiO2-SiO2 films in the visible range are reduced with the increasing of sol aging time, molar content of TiO2 and heat treatment temperature; The TiO2-SiO2/SiO2 double-layer films prepared on this basis have antireflective effect, and the average transmittances in the visible range of it are increased nearly 4%-5% more than glass substrate and the transmittance peak reached 100%; the surfaces of the films are smooth; in addition, the cut sides of UV of TiO2-SiO2/SiO2 double-layer films are moved to infrared with the increase of TiO2 content.
Abstract: The impact explosive temperature of reactive material is not only an important indicator to measure the ability of explosive reaction, but also a required parameter to carry out thermo-chemical calculation. So there is important practical significance to study the impact explosive temperature effect of reactive material. Based on one-dimensional shock wave, thermodynamics and physical chemistry theory, mathematical analysis model of impact explosive temperature vs. mass ratio of the reactive material is established. By MATLAB programming, the curve of impact explosive temperature vs. the mass ratio of PTFE/Al reactive material is received, which can be used to analyze variations. Fitting function equations is obtained by MATLAB CFTOOL. At last, the contrast of original calculation curve with fitting curve validates the appropriateness of the fitting function equations. From the view of impact explosive temperature effect, we suggest that the established model and research method can be applied to the dynamic properties research of other reactive material.
Abstract: From the origin of the copper clad aluminum wire, Discussed copper clad aluminum wire structure, performance, and an overview of the preparation process of the copper clad aluminum wire, Analysis copper clad aluminum wire applications and problem in applications, and finally summed up: As long as we solve good copper clad aluminum recycling, and to formulate product standards for copper clad aluminum wire, copper clad aluminum wire can become save a lot of copper resources, reduce raw material costs, and to promote the cable industry is continuing the development and creation of resource-saving society in China new type of conductor material.
Abstract: The process of synthesizing bauxite based β-SiAlON by using carbon silicon composite reducing agent was studied. Specimens prepared by mixing bauxite (Al2O3 68%), carbon black and silicon are nitrided at 1100~1550°C for 6h. The mass change ratio of the specimens are determined; Phase composition and microstructure of some specimens are examined by XRD, SEM and EDS. The results are compared with those of specimens using Si and C separately as reducing agent. It is found that at 1100~1200°C only Si reacts with N2 and SiO2 to form Si2N2O; At 1300~1400°C, C takes part in reduction-nitridation with subsequent formation of SiAlON; At 1450~1550°C, there is noticeable increase in β-SiAlON formation, the optimum temperature is 1500°C. The amount of β-SiAlON formed is higher and crystale growth is better than that of single reducing agent.
Abstract: The corrosion characteristics of various steels used by ocean wave energy equipment in sea water are investigated by electrochemical tests in this paper. The electrochemical experiments are carried out to research the corrosion rules of Q235, 20# steel, 16Mn and X42 through contrast experiments. Polarization curves and electrochemical impedance spectroscopy (EIS) are got by electrochemical workstation. Corrosion rates and corrosion potentials are analyzed from the polarization curves, and corrosion rules are founded. In addition, EIS is analyzed, and the analysis results are consistent with the results of polarization curves.
Abstract: The aim of this paper is to investigate the microstructural characteristics and creep resistance of Mg-(8-12 Wt. %) Zn-(2-6 Wt. %) Al alloys in order to get a better overall understanding of these series alloys. The results indicate that the alloys studied with the ratio of Zn/Al concentration between 2 and 3 exhibit high creep resistances, and the alloy ZA124 with the continuous network of τ precipitate along grain boundaries shows the highest creep resistance. The creep resistance of alloys decreases significantly due to eutectic phase, eutectics and β compounds appearing, especially the creep properties of alloys containing eutectic phase and β phase with lower Zn/Al concentration are obviously inferior to other alloys.
Abstract: During the process of laser cladding thin-walled components, warping deformation generated on the thin-walled components due to the difference between the change of temperature field and thermal expansion coefficient of materials. Through the micro-forging regulation, the internal stress of laser cladding layers changed, reaching the purpose of suppressing the warping plastic deformation generating on the thin-walled components. This paper utilized Ansys software to calculate the temperature field and stress field of the process of laser cladding 304 stainless steel regulated by micro-forging, and compared to the measurement result of the warp deflection and stress. The results indicated that reasonable effective micro-forging can effectively restrain the warp occurring on the thin-walled components treated by laser cladding.
Abstract: PAN and P(AN-co-MA) nanofibers have been successfully prepared by electrospinning. The mass concentration is 6%-12%, voltage of 15-25 kV, tip-to-collector distance is 25 cm. The morphology of the obtained samples was measured by a Scanning electron microscopy (SEM). The results showed that there were some large beads distributed on the PAN fiber skeleton when the spinning solution concentration is low. With the spinning solution concentration increased, the bead structure is gradually reduced. The fiber diameter increased with the concentration. For the synthetic reaction mixture P(AN-co-MA), it could obtain uniform nanofibers easily
Abstract: In order to study the corrosion characteristics of 16Mn and Q235B steel in natural seawater, the indoor contrast corrosion experiments are carried out in seawater by electrochemical method. Tafel polarization curves and electrochemical impedance spectroscopy (EIS) techniques are employed to investigate the corrosion electrochemical behavior of 16Mn and Q235B steel, which are acquired by electrochemical workstation. The results of polarization curves and EIS reveal the respective corrosion rules of 16Mn and Q235B steel in natural seawater. At last, the different influence of rust layer on the corrosion process of 16Mn and Q235B steel is analyzed contrastively.
Abstract: The metal parts laser shaping process dynamical identification is fulfilled by the method of experiment. Through step response experiments, mathematical models between the cladding height and the laser power, the scanning speed, or the powder flowrate are established respectively. Simulating experiments validate these identification models. From the identification models, the metal parts laser shaping process is understood, which is the basement for designing closed loop control in forming process and is significant to improve the quality of formed parts.