Applied Mechanics and Materials Vols. 541-542

Abstract: Removed at authors request

Abstract: Electron beam melting (EBM) has been recognized as a revolutionary manufacturing process. This layer-by-layer additive manufacturing process has shown great promise for fabrication of biomedical implants and aerospace components. This paper represents an investigation into the particle size distribution, morphology and flow-ability of Ti6Al4V powder used in EBM process. The effect of recycling of the powder on the chemical properties has been investigated. Results show that recycling increases the weight percentage of interstitial elements. The flow-ability and apparent density of the powder were measured before and after recycling process and no change was observed.

Abstract: To enhance anti-erosion property of artillery barrel and prolong the using period of the artillery, some new technologies are summarized and discussed in this paper, which including electric explosion spraying technology, hypersonic flame spraying technology and plasma surfacing. The experimental results show that the electric explosion spraying technology is a feasible method to prepare coating for the anti-erosion property of 100mm diameter artillery barrel.

Abstract: The effect of SO₃ on the mineral composition and performance of phosphoaluminate clinker was investigated by means of XRD, IR and SEM. Also, the compressive strength of clinker was performed. The experimental results showed that a certain amount of SO₃ would promote the formation of calcium phosphoaluminate mineral, which was good for the strength development of phosphoaluminate clinker. Moreover, the addition of SO₃ was benefit to the formation of C₄A₃ in phosphoaluminate clinker. So, the 5% dosage clinker owns a good strength development.

Abstract: As diamond wire saw machining device, the vibration characteristics of beaded rope has important implications on the processing quality and the service life. Based on it, this topic used the Galerk and complex modal method to research the changes of natural frequency of lateral vibration characteristics under different parameters, and comparative analyzed the effect of two methods on the natural vibration characteristics. Firstly, through an analysis on vibration mechanics model used complex modal method, the author obtained the exact solution of natural frequencies under different parameters, after that, utilized the Galerkin method to discrete the system vibration equations for getting the first N natural vibration characteristics. According to comparative analyzed the natural vibration characteristics of two algorithms, the results showed that, using appropriate Galerkin method will obtain more accurate solutions,as well as provide theoretical support on suppressing the vibration of beaded rope.

Abstract: The high-pressure water jet is utilized to perform impact test on coated surfaces with different hardness. The decoating effect is measured and the surface roughness change can be tested by White-light Interferometer (WLI). Also the microstructure of surface damage after impact test is analyzed. The result shows that when utilizing high-pressure water jet to clean the coating, it’s a better choice to start at the place where the coating is broken. The gap will be enlarged rapidly and the decoating velocity will increase linearly. Otherwise, the impact of water jet will cause surface damages and generate holes of particular shape. This kind of hole is flat in the middle, then forming a sunken district and apophysis successively along the radius outwards.

Abstract: Rare earth metal complexes have special characteristics, such as extremely narrow emission bands and high internal quantum efficiencies, which are suitable to be used as the emission materials, chemistry and biological technology. Ternary nano complex of terbium gatifloxacin phenanthroline was synthesized.The composition and structure of ternary complex were characterized by element analysis, Mass Spectrometry (MS), UltraViolet Absorption Spectrometry (UV) and fluorescence spectra(FS). The influences of solubility, thermal stability and luminescent properties of complex as well as addition of phenanthroline secondary ligands on the fluorescence spectra of the ternary complexes were studied. The results of fluorescence spectra analysis showed that partial energy was transferred from Characterization to terbium ions by intramolecular energy transfer processes, meanwhile, the addition of phenanthroline can effectively increase the luminescence intensity of terbium icons. The complex possessed well luminescence and showed characteristic emission peaks of Tb³⁺ under UV light excitation and emitted strong green fluorescence. Moreover, in an ITO/PVK/Tb(GFLX)₃Phen/Al device, Tb³⁺ ion can be excited by intramolecular ligand-to-metal energy transfer process. The main peak of emission at 545 nm is attributed to ⁵D₀→⁷F₂ transition of the Tb³⁺ ion, and this process results in the enhancing green emission. Biological actrivity properties of the rare earth complex was well studied.

Abstract: Activated carbon (AC) was reported as a promising catalyst to selectively produce phenolic compounds from biomass using the micro-wave assisted catalytic pyrolysis technique. In order to evaluate the catalytic performance of the AC under the traditional fast pyrolysis process, analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique was applied for the catalytic fast pyrolysis of biomass mixed with the AC. Polar wood was selected as the feedstock, and experiments were conducted to reveal the AC-catalyzed poplar wood pyrolysis behavior and product distribution. The results indicated that the AC was also effective for the phenolics production in the traditional fast pyrolysis process at 350 °C. It could promote the formation of phenolic compounds, and inhibit most of the other pyrolytic products. The maximal phenolics yield was obtained at the biomass to catalyst ratio of 1:4, with the peak area% over 50%.

Abstract: In this paper, the law of hydration expansion of polymer microsphere and the plugging rate of polymer microsphere under condition of different influencing factors such as hydration time, mass concentration, and permeability are studied. The applicable conditions are optimized as following: The optimum hydration time, mass concentration, and formation permeability through laboratory experiment is 5 days 3000 mg/L~4000 mg/L, permeability under 4 um² respectively. Finally, oil displacement experiment is carried out under laboratory conditions. The results show that the enhancement in oil recovery obtained in core flow experiment is about 7 %, which suggests that it has a wide application prospects in tertiary oil recovery.

Abstract: Using B, Mo, and Fe powders as raw materials, Mo₂FeB₂ cermets-steel clad material has been prepared on steel 45 substrate by means of in-situ reaction vacuum and liquid phase sintering technology, and the influence of heat treatment on microstructure and properties has been studied. The influence of heat treatment on microstructure, and distribution of elements of the cladding-substrate bonding interface area has been investigated by SEM, EDS. Results show that there is an excellent metallurgic bonding between the cladding layer and steel substrate both before and after heat treatment, and heat treatment not only brings the cladding material grain size and microstructure refinement but also increases the thickness of the transition layer.