bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimized Asphalt Mixtures for Noise Reduction in Lithuanian Roads
Authors: Vaitkus Audrius , Andriejauskas Tadas , Čygaitė Laura , Židanavičiūtė Jurgita
Published: September 2014

In the world of growing economy and population, the need of transportation is rapidly increasing also raising problems of noise pollution. Environmental noise levels are increasing in parallel with increasing traffic flows resulting negative effects for society, wildlife and economy. The article gives an overview about the main transport noise source tyre/road noise, its generation mechanisms and influencing factors. One of the most effective and promising tyre/road noise solutions is low noise pavements, which has different noise reduction approaches. Low noise asphalt pavements and theoretical noise reduction principles are analysed in the paper as well as the development experience of particular low noise asphalt pavements for Lithuanian conditions.
Interactive Effects of Salt and Drought Stresses on Seed Germination of Ammopiptanthus mongolicus in Northwest China
Authors: Shen Xiao Xue , Chai Min Wei , Li Rui Li , Qiu Guo Yu
Published: September 2014

A study quantifying the role of the interactive effects of salt and drought stresses, generally co-occurred in deserts, on seed germination in Ammopiptanthus mongolicus was conducted in a constant temperature incubator. The experiment consisted of seven levels of salinity stress (0, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8% NaCl) as well as six drought stress levels (0, -0.2, -0.4, -0.8, -1.6 and-2.0 MPa PEG). Accordant to our expectations, the interactive effects of salinity and drought stresses were additive on seed germination percentages, germination rate, and germination energy; significant decreases were seen in all of them in response to increases in salt and/or drought stresses. Furthermore, regression coefficients of salinity (β1) were higher than drought (β2), indicating that salinity was the first factor, and drought was secondary for salt and drought mixed stresses.
Suggestions of Earthquake Action Value under Different Design Life
Authors: Jiang De Bao , Gu Xiao Jing
Published: September 2014

This paper has analyzed earthquake with different design life and 50 years with the same design basis of probability guarantee, proposed seismic design life under different reference values recommended.
Research on Visualization of Characteristic Parameters of Ionosphere
Authors: Wang Zhe , Ma Qing Jin , Shen Cun , Fan Jing , Jiang Chun Hua , Zhou Chen
Published: September 2014

In this article, the author uses computer graphics visual programming method and visually expresses ionospheric characteristic parameters. Firstly, the significance of visualization of ionospheric characteristic parameters was described, then visualization process and methods were discussed, and finally the results of visualization of ionospheric parameters in typical conditions were given. The results show that visualization method of ionosphere characteristic parameters can directly reflect ionospheric electron density, electron temperature and other parameters, which is conductive to an intuitive understanding of various physical phenomena in ionosphere.
Indirect-Direct Band Gap Transition by Van Der Waals Interaction Engineering in MoS2/WS2 Bilayer Heterojunction
Authors: Cao Hai Ning , Zhang Zhi Ya , Si Ming Su , Zhang Feng , Wang Yu Hua
Published: September 2014

First principles calculations based on the density functional theory (DFT) are employed to estimate the electronic structures of bilayer heterostructure of MoS2/WS2. The dependences of the band structures on external electric field and interlayer separation are evaluated. The external electric filed induces a semiconductor-metal transition. At the same time, a larger interlayer separation, corresponding to a weaker interlayer interaction, makes an indirect-direct band gap transition happen for the heterojunction. Our results demonstrate that electronic structure tailoring of two-dimensional layered materials should include both spatial symmetry control and interlayer vdW interactions engineering.
Analysis of Stability of Mine Airflow
Authors: Cui Chao , Xie Xian Ping , Luo Wen Gui , Wang Ting Jun , Li Jian Gong , Tan Xing Yu , Yin Xiao Yu , Su Mei Wei
Published: September 2014

Firstly, the causes of mine air flow instability were analyzed in this paper, then the paper applied fuzzy mathematics method and got construction method of the membership function of airflow stability. Wind resistance of shaft and lane, natural wind pressure, operating conditions of fan and other random disturbance conditions are defined by membership function of relative stability degree of mine airflow. This paper provided a quantitative analysis method for the mine airflow stability.
Study on Force Characteristics of Ultrasonic Vibration-Assisted Sawing Ceramics with Diamond Blade
Authors: Xiang Xin , Shen Jian Yun , Hu Zhong Wei , Xu Xi Peng
Published: September 2014

In the present research work, a new precision sawing technique is proposed, by which the ceramic workpiece is ultrasonically vibrated along the blade radial direction during the sawing operation using a diamond blade. In this study, experiments are conducted to study the sawing force characters of ultrasonic vibration-assisted sawing (UVAS) and conventional sawing (CS). The influences of the sawing parameters on the sawing force and force ratio are investigated. The results show that the sawing force in UVAS is smaller than those in CS. It was found that applying ultrasonic vibration to the sawing operation decreased the normal sawing force 18%-38% and tangential sawing force by 10%-25%. The force ratio in UVAS is lower than that in CS, which reveals that diamonds are easier to cut into the ceramic workpiece and the material machinability is improved.
A Three-Dimensional Fractal Analysis Method for Ground Monocrystal Sapphire Surface
Authors: Wang Qiu Yan , Liang Zhi Qiang , Wang Xi Bin , Zhao Wen Xiang , Wu Yong Bo , Jiao Li , Xie Li Jing
Published: September 2014

Conventional characterization methods of grinding surface using surface roughness parameters, e.g., Ra, depend on either the resolution of the measuring instrument or the length of the sample. But fractal dimension (FD) as a scale-independent fractal parameter is effective to evaluate the ground surface at any length scale and represent lots of surface phenomenon at its relevant length scales. In this paper, a three-dimensional (3D) box-counting fractal analysis method is used to investigate ground surface morphology of monocrystal sapphire by calculating 3D fractal dimension of the ground surface. The results obtained show that fractal dimension decreases with the increasing surface roughness. For the ground surface with higher fractal dimension, its microtopography is more exquisite with minor defects. Once the fractal dimension become smaller, deep cracks and pronounced defects are exhibited in ground surface. Moreover, the ground surface obtained in ductile mode has much higher fractal dimension than that in brittle mode. Therefore, the fractal analysis method has the potential to reveal the ground surface characteristics of monocrystal sapphire.
Studies on Grinding Conditions Affecting the Quality of Soft Magnetic Powder Cores
Authors: Ueno Tomoyuki , Tokuoka Terukazu , Nishioka Takao , Ohashi Kazuhito , Tsukamoto Shinya
Published: September 2014

Soft magnetic powder cores are made by pressurizing and molding pure iron powder covered with insulation film. The material is used as a component of electro-magnetic converter parts essential for automobiles, home electric appliances and electronic equipment. The material permits downsizing and higher performance of such equipment. The recent severer requirements for performance and dimensional accuracy need a new processing technology that warrants the required level of both magnetic performance and surface quality of the material. However in general, processing - grinding - soft magnetic powder cores can give rise to degradation of magnetic performance and/or chipping or plucking of the ground surface due to the mechanical damage of the insulation film and/or loss of structural particles from the material due to the increase in grinding resistance. The authors performed basic studies for various grinding conditions and wheels that could possibly affect the quality of the material with a view to eliminating these problems. As a result, factors that affect the surface quality were identified, and a method that warrants a higher surface quality was proposed.
Investigation on Properties of Magnesia Grinding Wheels Used in Silicon Wafer Grinding
Authors: Hao Bing Jun , Dong Zhi Gang , Gao Shang , Kang Ren Ke , Guo Dong Ming
Published: September 2014

This paper presents the results of an experimental investigation on molar ratios of MgO/ MgCl2 affecting the hardness of magnesia grinding wheels, which is one of the most important properties. Magnesite grinding blocks of different ratios of MgO/MgCl2 were prepared. The surface Rockwell hardness of which was tested under the same curing conditions. By an integrated assessment of the experimental studies of hardness and component, it is recognized that the molar ratios of MgO/MgCl2 can significantly affect the properties of magnesia grinding wheels. With the increase of MgO/MgCl2 molar ratio, hardness of the specimens increases. Scanning electron microscopy (SEM) studies on grinding blocks of different ratios indicated that micro needle shaped crystal structure of phase 5 are mainly responsible for hardness development. Finally the optimal recipe was selected in consideration of the characteristics of the silicon mechanical chemical grinding (MCG), which was verified to be effective by the following grinding experiment.
Essential Research in Machining Difficult-to-Machine Materials for Advancing MQL Cutting Technology with a Newly Developed Coated Tool
Authors: Shimada Syunki , Kohzaki Masao
Published: September 2014

This study is developing environmentally friendly cutting technologies of difficult-to-machine materials by MQL (Minimum Quantity Lubrication) cutting with Ti-B coated tools. In this research, we performed cutting experiments of difficult-to-machine materials in dry, MQL and wet conditions with non-coated tools. Cutting resistance in the MQL cutting was almost the same as that in the wet cutting. Moreover, damage of the cutting tool was not observed after the MQL cutting. Therefore the MQL cutting is expected to become an advanced cutting technology by using Ti-B coated tools because Ti-B film had high temperature lubricating properties and high wear resistance.
Effect of Coolant Supplied through Grinding Wheel on Residual Stress of Grinding Surface
Authors: Nakatsuka Nagatoshi , Hirai Yudai , Kusakabe Atsushi , Yao Yasuhiro , Sasahara Hiroyuki
Published: September 2014

We explored the effect of supplying coolant from the inner side of a grinding wheel on the residual stress caused by grinding. Effect of depth of cut on grinding temperature and residual stress was also studied. Results clarified that grinding with an internal coolant supply induced a larger compressive residual stress compared to a conventional external grinding fluid supply when depth of cut was large. In addition, grinding temperature in the internal grinding fluid supply was lower than in the external grinding fluid supply, as measured by infrared thermograph camera. Findings suggested that large compressive residual stress was obtained in the case of the coolant supplied from the inner side of the grinding wheel because temperature was lower than external coolant supply.
An Innovative Cooling Method for Grinding Process Based on Heat Pipe Technology
Authors: Chen Jia Jia , Fu Yu Can , He Qing Shan , Zhang Wei , Zhu Yan Bin
Published: September 2014

The core idea of the existing cooling methods in grinding process is making a large quantity of coolant into the contact zone. However, the practical quantity of coolant injected in the grinding zone is limited, and the large amount of coolant employed can cause pernicious effect to human health and the environment, and will largely increase the expenses. In order to solve this problem, an environmental friendly idea about enhancing heat transfer in the contact zone based on heat pipe technology is put forward in this paper. The new system, heat pipe grinding wheel (HPGW), based on this high-efficiency cooling technology is developed and its heat transfer principle is illustrated. Eventually grinding experiments with HPGW were carried out to verify the cooling effect by comparing with non-HPGW in grinding plain carbon steel. Results show that using HPGW can significantly reduce the grinding temperature with no coolant.
Tribo-Electrochemical Performance of Polycrystalline Silicon during ECMP Simulating Process
Authors: Zhai Wen Jie , Wang Jin Hu
Published: September 2014

The tribo-electrochemical performance of polycrystalline silicon was studied by Tafel polarization curves and electrochemical impedance spectroscopy (EIS), based on which the electrochemical mechanical planarization (ECMP) simulating test was done to investigate the effects of applied potentials on friction and material removal rate (MRR) with an ECMP simulating tester. According to the research, a suitable anode polarization potential is advantageous to promote the forming of passivation film with better corrosion inhibition in alkaline CeO2 polishing liquid, and forming of passivation film on silicon surface can increase both the friction between polishing pad and specimen and the MRR of silicon. This result provides theoretical supports and experimental bases for ECMP of silicon wafer to increase its polishing efficiency.
A Controllable Material Removal Strategy Considering Force-Geometry Model in Marine Propeller Five-Axis Belt Grinding
Authors: Wang Yong Qing , Hou B. , Ma Q. , Liu H.B. , Sheng Xian Jun
Published: September 2014

Belt grinding is characterized by elastic contact grinding. Generally, the non-uniform material in complex machining area could be removed by repeated grinding or longer dwell-time grinding to obtain the required grinding capacity, which leads to low efficiency, difficult dimension accuracy control and poor surface quality. It should be considered thoroughly surface geometry, grinding force and system stiffness in surface belt grinding. Belt grinding parameters can be then dynamically adjusted. This paper focuses on controlling material removal efficiently and uniformly in marine propeller belt grinding. The material removal process is modelled considering elastic contact between grinding wheel and workpiece. Then, a grinding depth and grinding dwell time control strategy of surface belt grinding is proposed based on rigid-flexible coupled analysis. The variable feed grinding experiments were carried out on the developed five-axis CNC belt grinding machine integrated measuring and machining. The marine propeller with cast aluminum bronze (ZCuAl8Mn13Fe3Ni2) was employed to validate the proposed controllable material removal strategy. It is shown that the proposed strategy is feasible and efficient.
Research on Performance of Fixed Abrasive Tools of Polishing 6H-SiC Wafers
Authors: Lu Jing , Hu G.Q. , Huang G.Q. , Fang C.F. , Xu X.P.
Published: September 2014

6H-SiC single crystal substrates are considered to be suitable for thin film growth of semi-conductive GaN with wide energy bandgaps, because the lattice mismatch between 6H-SiC and GaN is quite small compared with sapphire substrates. However, the process of SiC wafer prior to epitaxial growth is quite difficult due to its high hardness and chemical stability. The chemical mechanical polishing (CMP) is typically performed in semiconductor device planarization, but the polishing slurry is not environmental friendly and the polishing efficiency is very low. In this paper, polishing experiments were conducted on 6H-SiC wafers using a flexible fixed abrasive film fabricated by sol-gel technique. Other three fixed abrasive tools bought from the different companies were also chosen in these experiments. Abrasive wear resistance on the different tools was observed with the increase of polishing time. Studies were also made on the surface micrographs and roughness of the 6H-SiC wafers polished by the four different tools in order to evaluate the tool performance. The results indicated that poor wear resistance of abrasive were showed in tool C and D, less abrasive worn out in the sol-gel polishing film and tool B. The surface quality of 6H-SiC wafer polished by the sol-gel polishing film was much better than the other three tools, and it attained the lowest surface roughness Ra=0.003 μm.
Keywords: Sol-Gel polishing film; Fixed abrasive tools; 6H-SiC wafers
Deformation and Removal Characteristics of Multilayered Thin Film Structures in Nanoscratching and Diamond Lapping
Authors: Kang Cheng Wei , Huang Han
Published: September 2014

The deformation and removal mechanism of a multilayered thin film structure involved in nanoscratching and diamond lapping processes were investigated. The results obtained from the two processes were compared, in terms of deformation characteristics and surface finish. It was found that both nanoscratching and lapping demonstrated similar characteristics. This work provides insight into the deformation and removal of a thin film multilayered structure under mechanical loading, and thus the outcome is of value for developing the efficient machining process for such structures.
Experimental Study on the Cutting Performance of In Situ Fabricated TiB2 Toughened TiN-Based Composite Ceramic Tool in Turning Stainless Steel
Authors: Liu Han Lian , Shi Qiang , Huang Chuan Zhen , Wang Li Mei , Zou Bin , Yang Zhi Hong
Published: September 2014

A new developed TiN-TiB2 ceramic cutting tool material (marked as TBN5) with high comprehensive mechanical properties was fabricated by the in-situ integration synthesis process. The cutting performance of TBN5 tool in continuously turning the austenitic stainless steel 1Cr18Ni9Ti was experimentally investigated; the failure modes and failure mechanisms of the cutting tool TBN5 were analyzed combined with its mechanical properties. Aiming at the materials removal amount, the optimal cutting parameters of TBN5 tool in turning 1Cr18Ni9Ti were firstly obtained by the orthogonal tests; and then with this cutting parameters, the cutting performance of TBN5 compared to the commercial tools LT55 and SG4 was studied. The results showed that the advanced tool TBN5 could get longer tool life than LT55 and SG4; the main failure modes of TBN5 were flank wear, breakage and the flaking of main cutting edge. The scope of its flaking was smaller and diffusion wear was not obvious, which was related to the higher fracture toughness and the higher thermal conductivity of TBN5.
A 5-Axis Coordinated CNC Grinding Method for the Flank of a Non-Coaxial Helical Micro-Drill with the Cylinder Grinding Wheel
Authors: Liang Zhi Qiang , Jian Hong Chao , Wang Xi Bin , Zhao Wen Xiang , Zhang Su Yan , Otani Yusuke , Xue Si Yi
Published: September 2014

Micro-drilling become more widely used from precision mechanics to electronics. Nowadays, the main commercial tools are planar point micro-drills. However, that geometry often causes a high thrust force, high temperature, and rapid wear during micro-drilling. Furthermore, it is difficult to adjust the four flank surfaces to accurately intersect at one point, particularly when the drill diameter becomes smaller. To solve this problem, non-coaxial helical drills points have been proposed by some researchers, and is characterized by a continuous helical flank instead of the piecewise planar flank. Its drilling performance is improved compared with planar drill point. This study presents a 5-axis coordinated CNC grinding method of the non-coaxial helical drill flank. Mathematical models of the drill flank and its engagement line between cylinder grinding wheel and drill tool are established, and then the path of the grinding wheel with respect to the drill tool is obtained. In order to verify the availability of the proposed methods, three dimension (3D) grinding simulation of non-coaxial helical drills with diameter 0.5mm was carried out using the CAD software, and then were fabricated on a 6-axis Makino CNC tool grinder. The ground micro-drills examined by 3D laser scanning microscope show good identity with the simulated result. These indicate that the manufacturing model presented in this paper provides a practical and efficient method to grind the flank of a non-coaxial helical micro-drill.
Future Prospects for CMP Equipment - Design Considerations According to Substrate Size and Shape
Authors: Jeong Hae Do , Kim Hyoung Jae , Choi Hon Jong
Published: September 2014

CMP Technology is still expanding its application field to realize planarization of complicated structures for More-Moore and More-than-Moore devices. The CMP equipment has been developed based on simple rotary motion but with more sophisticated systems for 300mm wafer applications. This paper deals with future prospects of the CMP equipment for micro-and nanopatterns on different types of substrate which are recently on demand to meet technological requirements. These industrial environments make equipment makers grow out of insisting rotary type motions anymore and get new opportunities. This paper describes basic design considerations according to substrate size and shape, and shows a couple of examples for not only large sized wafer, display panels and printed circuit boards, but also thin, flexible and continuous films. Finally, we hope that the design considerations for future CMP equipment make many discussions and solutions to achieve higher quality and throughput in the field.
Modeling and Simulation of Surface Topography Evolution in Electrical Discharge Machining (EDM)
Authors: Zhou Tian Feng , Ma Li Zheng , Liang Zhi Qiang , Wang Xi Bin
Published: September 2014

This paper aims to quantify the effects of the machining condition on the surface topography in electrical discharge machining (EDM), including pulse current, pulse duration and so on. Firstly, the heat source of a single electrical pulse is defined by Gauss distribution, and the thermal effects of machining parameters on the workpiece material erosion are simulated by Finite Element Method (FEM) package ANSYS. Then, the crater size of a single pulse is numerically simulated based on the thermal model of a single pulse discharge. Furthermore, the superposition of multiply craters created by continuous pulse discharges in a random distribution is calculated by MATLAB software program, so that the evolution of the surface topography can be obtained with the combination of FEM simulation and topology calculation. In this way, the surface roughness is quantitatively calculated from the specified EDM parameters.
Performance of EC-PCD Made of Boron Doped Diamond as an Electrode for EDM of Cemented Carbide
Authors: Chen William , Iwai Manabu , Ninomiya Shinichi , Suzuki Kiyoshi
Published: September 2014

Electrically conductive PCD (EC-PCD), which was made of electrically conductive diamond particles, was applied to an electrode for EDM. In this study, properties of EC-PCD electrode in the EDM of cemented carbide were investigated and the results were compared with those of copper-tungsten (Cu-W) electrode and standard PCD (S-PCD) electrode. In terms of EDM speed, 35μm/min with Cu-W electrode, 15μm/min with S-PCD electrode and 22μm/min with EC-PCD were recorded. As for the electrode wear rate, though Cu-W electrode wore by 20-30%, S-PCD and EC-PCD did not wear at all and even the electrode length became longer by several micro meters. Roughness value of the EDMed surface was Rz=8μm with both Cu-W and S-PCD, while it was Rz=3μm in the case of EC-PCD. From the above, it was found that EC-PCD showed excellent performance in the electrode wear rate and the roughness of the EDMed surface, though EDM speed was 0.7 times of Cu-W electrode.
Research on Material Removal Mechanism of Single Grit Cutting Based on FEM Simulation
Authors: Yan Lan , Jiang Feng , Fang Cong Fu
Published: September 2014

Grinding process can be considered as micro-cutting processes with irregular abrasive grits on the surface of grinding wheel. The study of grit-workpiece interaction through single grit cutting was an important contribution to describe material removal process in the grinding process. This paper presented a finite element simulation model for the analysis of AISI D2 cutting process using alumina abrasive grit. Finite element simulations of AISI D2 single grit cutting processes were performed using AdvantedgeTM software. Results of material deformation, forces, the critical depth of cut, temperature and material removal rate were discussed.
Usage of Industrial Robots as Flexible Handling Devices Supporting the Process of Three Dimensional Conductive Pattern Generation
Authors: Buschhaus Arnd , Franke Jörg
Published: September 2014

Due to their vast number of benefits, plenty of complex and miniaturized three dimensional molded interconnect devices are developed. One especially demanding process step during their manufacturing is the geometrical exact creation of the conductive pattern layout on the different substrates’ faces. Therefore, sophisticated and flexible technologies like laser direct structuring or printing processes can be used, which are subject to multiple research activities, concentrating for example on coating materials or process parameters. An additional aspect is the necessity of providing a flexible and sufficiently accurate handling device, which three dimensionally moves the substrate relative to the process nozzle applying the coating material. For this task industrial robots could be used, which inherit multiple beneficial features. One main drawback of using this type of kinematic is their relative low absolute accuracy of a few hundred microns, which is not sufficient for moving the substrate during the process with the needed accuracy.
On Technological Uses of Local Strain Patterns of the Commercial Zr-Nb Alloys
Authors: Zuev Lev B. , Zykov Ilya , Barannikova Svetlana A.
Published: September 2014

Plastic flow localization behaviour has been investigated in commercial Zr alloys used in the nuclear power industry. The type of deformation localization pictures corresponding with the stage preceding material fracture is described. Proposed is a method for assessing the reserve ductility of the metal subjected to deformation in rolling of thin-wall Zr alloy tubes by examining the local strain patterns.
Kinetics Flash Cathodoluminescence in Crystals with Nonstationary Defectiveness
Authors: Lisitsyn Viktor M. , Karipbayev Zhakyp , Stepanov Sergey , Trefilova Larisa , Dauletbekova Alma , Polisadova Elena F. , Omelkov Sergey
Published: September 2014

The present paper is devoted to the study of the kinetics of luminescence flash in LiF-WO4 crystals and development of the model to describe the kinetics of cathodoluminescence growth under pulsed excitation.
Study of the Effect of Butylenes Content in Butane Fraction on Butane Dehydrogenation Process
Authors: Kasyanova L.Z. , Karimov E.Kh. , Karimov O.Kh. , Dmitriev Yuri K.
Published: September 2014

The paper shows the effect of butylenes concentration in feedstock on the process of dehydrogenation of butane into butylenes using chromia-alumina-potassium catalyst. Butylenes as contained 1 to 7 % wt. in butane slip completely without hindering the process of converting of butane.
The Synthesis of Iodbenzimidazoles and Iodbenzoxazoles via Iodination of Arenediazonium Tosylates
Authors: Hong Nguyen T.T. , Trusova Marina E.
Published: September 2014

The present study describes a synthesis of a series of iodine-benzimidazole and iodine-benzoxazole derivatives. The new and cheap method for its obtaining is developed. All compounds were characterized by physical, chemical, analytical and spectral data.
Formation of Coatings on Titanium Substrates Obtained from Mixtures of Tungsten and Cobalt Salts Using Shaped-Charge Explosion
Authors: Li Julia , Kulkov Sergey , Kozulin Alexander A. , Kinelovskii Sergey A. , Kulkov Sergey N.
Published: September 2014

In this paper the coatings on the titanium substrate surfaces obtained by the shaped-charge synthesis have been investigated. The shaped-charge synthesis was carried out using mixtures with specially synthesized complex salts containing W and Co. The studies included X-ray analysis, X-ray fluorescence analysis, and the measurements of coating microhardness. The relationship between mechanical properties of coatings and their phase and structural state has been determined.
Development of Coupled Model of SHS-Extrusion
Authors: Mekhanich I.V.
Published: September 2014

In this paper mathematical model of self-propagating high-temperature synthesis combined with extrusion was proposed and investigated. The problem was solved in one-dimensional formulation with consideration of viscous, thermal and concentration stresses. Evolution of temperature, density was investigated.
Math Modeling of Vacuum Conductive Timber Drying
Authors: Goreshnev M. , Litvishko E.
Published: September 2014

The article is devoted to the mathematical modeling of vacuum conductive timber drying. Analysis of known mathematical models allowed revealing their advantages and disadvantages. The modeling block diagram based on the drying periods is proposed. Lykov’s equations have been selected to solve heat and mass transfer problems. The comparison of experimental and calculated data has been conducted.
Quasi-Static Loading of Single Crystal Plasticity Analysis
Authors: Yanz Anton Yu. , Teplyakova Ludmila A.
Published: September 2014

This paper is devoted to one of the crystal plasticity physical theories for description of the crystalline solid behavior under high strains. The boundary value problem is formulated to consider uniaxial compression of aluminum single crystal. The numerical experiment data were obtained during the solving of this problem, which analysis shows good accordance with the full-scale experiment.
Structure Formation of Sulfur-Based Composite: The Model
Authors: Kiselev Denis G. , Korolev Evgeniy Valerjevich , Smirnov Vladimir
Published: September 2014

In material science the simultaneous application of theoretical examination, experimental and numerical studies are often required. This is especially true for modern composite materials with extra inter-boundary nanoscale layers. Thickness of layers is usually about tens of nanometers, while diameters of particles of filler are about several hundreds of nanometers. Thus, during the theoretical study and numerical experiments the size and properties of inter-boundary layer must be taken into account. The proper choice of the model is the key factor for the adequate results of simulation. In the present work we have derived such a model. The system under investigation – disperse-filled composite material with inter-boundary layers of different properties – is represented by particle system; these classes of models can be characterized by high generality. Initial equation for the law of motion is sequentially extended with terms which account for different phenomena – conservative binary interaction, non-conservative interaction with environment, interaction with planar boundaries and non-conservative particle-particle interaction via inter-boundary layer. The reduction of the law of motion to the system of ordinary differential equations had opened the possibility for utilization of the vast majority of numerical algorithms for the prediction of the structural properties of nanomodified sulfur-based composite.
The Influence of Thermal Diffusion on the Redistribution of Alloying Element between the Coating and Base under Surface Heating
Authors: Kryukova Olga N. , Chepak-Gizbrekht Maria
Published: September 2014

The problem has been analyzed on alloying elements redistribution between the coating (containing Cr and N) and the substrate (Si) in condition of surface heating. The model takes into account the effect of thermal diffusion on the redistribution of elements. The analytical solution of the particular linearized problem about redistribution of elements in the substrate coating is presented. It is shown that the thermal diffusion significantly affects the impurity distribution, resulting in the appearance of supersaturated or depleted regions.
Two-Temperature Two-Dimensional Model of Underground Shale Heating by Electromagnetic Field
Authors: Martemyanov Sergey M. , Maslov Alexei L.
Published: September 2014

A two-dimensional two-temperature model of shale stratum heating by high-frequency electromagnetic field is proposed. The heat exchange between solid rock and gas contained in pores is shown to significantly affect temperature field characteristics. The stratum gas filtration and reaction heat effects are taken into account as a first approximation.
Heat and Mass Transfer in Viscous Fluid Flows in Open Cavities with Moving Boundaries under Cooling the External Contour
Authors: Krainov A.V. , Pashkov E.N. , Yurovskiy P.G.
Published: September 2014

The paper presents the numerical research heat mass transfer and hydrodynamics in the motion of viscous fluid in the rectangular cavity in the consideration of the crystallization process. The hydrodynamic Figure of viscous fluid and temperature fields obtained. The impact of hydrodynamic parameters and geometrical characteristics for forming crystallization front is studied.
Investigation of Genotoxicity of Gold Nanoparticles Prepared by the Electric Spark Dispersion Method
Authors: Plotnikov Evgenii , Zhuravkov Sergey P. , Gapeyev Andrew , Plotnikov Vladimir , Martemiyanov Dmitry
Published: September 2014

The paper presents the results of investigations of genotoxicity and morphological characteristics of nanoscale gold particles prepared by the electric spark dispersion method in a water medium. To investigate the properties we used comet assay, transmission electron microscopy, thermal desorption of nitrogen (BET). It was revealed, gold particles did not cause DNA damage at low concentrations (0.01 - 0.1 mg/ml) and detectable level of genotoxicity of gold nanoparticles is observed at concentrations of 0.3 mg/ml and above.
Correct Multilevel Discrete-Continual Finite Element Method of Structural Analysis
Authors: Akimov Pavel A. , Belostosky Alexandr M. , Mozgaleva Marina L. , Aslami Mojtaba , Negrozov Oleg A.
Published: September 2014

The distinctive paper is devoted to correct multilevel discrete-continual finite element method (DCFEM) of structural analysis based on precise analytical solutions of resulting multipoint boundary problems for systems of ordinary differential equations with piecewise-constant coefficients. Corresponding semianalytical (discrete-continual) formulations are contemporary mathematical models which currently becoming available for computer realization. Major peculiarities of DCFEM include universality, computer-oriented algorithm involving theory of distributions, computational stability, optimal conditionality of resulting systems and partial Jordan decompositions of matrices of coefficients, eliminating necessity of calculation of root vectors.
Investigation of the Influence of Hydroimpulsive Mechanism Design Parameters on the Formed Impulse
Authors: Tsygankova Maria
Published: September 2014

The following article considers mathematic modeling of hydroimpulsive power systems. Using the MATLab software environment the author studies the influence of design parameters on the formed impulse. Consequently a new headless hydroimpulsive power mechanism is offered and described in detail and a basic diagram is given. This system can be used for designing new hydroimpulsive rock-drilling machines to intensify the process of drilling.
Partial Discharges Characteristics in Oil Shale of Various Deposits
Authors: Koryashov Ilia A. , Lopatin Vladimir V. , Bukharkin Andrey A. , Martemyanov Sergey M.
Published: September 2014

Attention to oil shale processing as unconventional energy source grows significantly. Electrical discharge phenomena application allows creating new efficient technology. Dynamics of PD basic characteristics of voltage in oil shale is described in this paper. Thermodestruction with abnormally high rate is occurred and caused by PD activity. Critical PD incept under low electrical intensity due to oil shale porosity, anisotropy and heterogeneity. PD induce treeing with following electrothermal breakdown. Organic content has influence on electrical discharges phenomena in oil shale. Therefore, the detailed study of PD, treeing and breakdown in oil shale allows developing an efficient method of inferior solid fossil fuels processing.
Materials of New Generation in Nuclear Power Industry
Authors: Shamanin Igor , Bedenko Sergei , Gubaydulin Ildar , Novikova Nataliya
Published: September 2014

The results providing advantages of thorium-232 as a reproducing nuclide in comparison with uranium-238 as a part of nuclear fuel of new generation reactors are presented. The explanation of the effects which were found earlier in numerical simulation of parameters of open thorium - plutonium nuclear fuel cycle is offered. Scientific and technical solutions allow considering the possibility of including thorium-232 in the fuel of nuclear reactors, which are based on existing design solutions, and beginning the design of new generation materials: a new generation of fuel rods and fuel assemblies, where the isotope uranium-238 will be completely replaced with thorium-232.
Structure and Properties of Surface Layers Obtained by Atmospheric Electron Beam Cladding of Graphite-Titanium Powder Mixture onto Titanium Substrate
Authors: Lenivtseva Olga G. , Golovin Evgeniy , Samoylenko Vitaliy V. , Mul Daria , Golovin Dmitriy
Published: September 2014

The cladding of titanium and graphite powders on the cp-titanium workpieces using the electron beam injected to the atmosphere provided the formation of the surface layers with a high content of high-strength carbide particles. The main structural components in cladded layers are α-Ti (αʹ-Ti), titanium carbide and graphite. Electron beam current is the main technological parameter defining a thickness of the hardened layer. An increasing beam current ranged from 20 to 23 mA leads to the cladded layer growth up to 2.9 mm. However, in this case a significant decrease of the microhardness level and the wear resistance level of the cladded layer is not observed. An average microhardess value of the hardened layer is of 430 HV. Under the conditions of friction against fixed abrasive particles, a wear resistance level of the cladded layers is by 32-45 % larger than that of cp-titanium.
The Application of Radio Frequency Magnetron Sputtering for Fluoropolymer Surface Modification
Authors: Malchikhina Alena I. , Bolbasov Evgeny N. , Tverdokhlebov Sergei I.
Published: September 2014

The paper investigated the properties of the multilayer system: metal with polymer layer modified by radio frequency magnetron sputtering of a solid target made from hydroxyapatite. The material of the polymer layer is thermoplastic copolymer of tetrafluoroethylene with vinylidene fluoride. The roughness parameters of metal, polymer, and hybrid substrates are determined using atomic-force microscope. Calcium phosphate coatings increase the surfaces roughness of polymer and metal materials, thus presenting a stimulating factor for the attachment and proliferation of osteogenic cells. Wettability of the coatings was investigated by the “sit” drop method of the “Krüss Easy Drop” installation by measuring the effective contact angle. The hydrophobic polymer surface becomes hydrophilic after modification and the surface free energy increases.
Effect of Gaseous Medium Pressure on Plasmadynamic Synthesis Product in the C-N System with Melamine
Authors: Shanenkov I.I. , Sivkov Aleksandr , Pak Alexander Y. , Kolganova Yu.L.
Published: September 2014

The possibility of plasmodynamic synthesis in the carbon-nitrogen system when using melamine as a precursor is described in the paper. The system based on the capacitive energy storage, which allows simultaneously powering the two opposite-directed coaxial magnetoplasma accelerators, is developed. The effect of gaseous medium in the processing chamber of the system on the synthesis product is investigated by applying such techniques as X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). It is demonstrated that an increase in nitrogen pressure results in the structural and morphological changes in the synthesized sample, which might be caused by the increased carbon nitride yield and a great number of the appearing C-N bonds.
A Decrease of Residual Stresses in the Elastic-Plastic-Creep Medium at Temperature Influence
Authors: Polonik Marina V. , Rogachev Egor E.
Published: September 2014

Within the linear theory of elastic-plastic body we carried out the modeling of technological process of annealing: slow heating stage, the holding stage under constant temperature and slow cooling step. Holding stage is simulated with consideration of creeping properties of materials. Boundary value problems are examined and patterns responsible for the removal of residual stresses at temperature influence are described. An analytical solution is found. It is proved that the holding stage is essential for describing the process of residual stress relief.
Principal Indicators for Efficiency Assessment of Resource Management in Foundry Production
Authors: Vidayev Igor G. , Martyushev Nikita V. , Sidorenko Tatyana V. , Ivashutenko Aleksander S.
Published: September 2014

The article gives a short target analysis of efficiency assessment as applied to casting techniques. Basic principles of efficiency assessment are defined. Efficiency criteria are proposed to optimize and quantify the efficiency of various prospective and existing foundry technologies. Functional, energy and resource criteria are selected as prime criteria. However, as shown in the article, energy criteria are the most common for comparison and assessment of manufacturing practices. The article reflects the fact that consumption of electrical, mechanical and other kinds of energy in socially-relevant production may be highlighted as an important indicator of technification in modern society development. The study leads us to the conclusion that the most common indicator of technification of any kind (social, informational, manufacturing, etc) is the efficient use of social time.
Morphological, Physical and Chemical Characteristics of Biocompatible Nano-Sized Carbonate-Substituted Hydroxyapatite
Authors: Trubitsyn Mixail Aleksandrovich , Dat Doan Van , Le Van Thuan , Gabruk N.G. , Oleynikova I.I. , Shuteeva T.A.
Published: September 2014

Hydroxyapatite and its compounds are important and promising inorganic biomaterials that can be used in dentistry and bone surgery due to its biocompatibility with the bone tissue of a living organism. The paper presents the synthesis of carbonate-substituted hydroxyapatite powders and studies their morphology, physical and chemical characteristics and biocompatibility in vivo. The synthetic carbonate-substituted hydroxyapatite are biocompatible, and they do not cause degenerative changes in the surrounding tissues. The result of this research suggests that the carbonate-substituted hydroxyapatite is promising biomaterial for orthopedic and dental prosthetics.
Preprocessing of Coefficients for Reusable Continuous Wavelet Transform
Authors: Khamukhin Alexander A. , Khamukhin Alexey A.
Published: September 2014

The division into two stages of the Continuous Wavelet Transform (CWT) computing is proposed. This is expedient in circumstances when CWT is repeated many times, e.g., for online detection of nonstationary signal singularities. It is shown that the preprocessing of wavelet coefficients in the first stage can significantly reduce computing time required in the second stage. The comparative estimation of the runtime reduction in the second stage of CWT calculation is deduced.
Theoretical Study of the Heat of Transport in a Liquid Ni50Al50 Alloy: Green-Kubo Approach
Authors: Evteev Alexander V. , Levchenko Elena V. , Belova Irina V. , Abdank-Kozubski Rafał Leszek , Liu Zi Kui , Murch Graeme E.
Published: September 2014

We analyse the formalism of transport in a binary system especially focussing on a detailed consideration of the heat of transport parameter characterizing diffusion driven by a temperature gradient. We introduce the reduced heat of transport parameter Qc*' which characterizes part of the interdiffusion flux that is proportional to the temperature gradient. In an isothermal system Qc*' represents the reduced heat flow (pure heat conduction) consequent upon unit interdiffusion flux. We demonstrate that Qc*' is independent of reference frame and is practically useful for direct comparison of simulation and experimental data from different sources obtained in different reference frames. Then, we use equilibrium molecular dynamics simulations in conjunction with the Green-Kubo formalism to study the heat transport properties of a model of the liquid Ni50Al50 alloy at three state points within the temperature range 1500 – 4000 K. Our results predict that in the liquid Ni50Al50 alloy in the presence of a temperature gradient Ni tends to diffuse from the cold end to the hot end whilst Al tends to diffuse from the hot end to the cold end.
Stress Field in Rolls under Load – Measurement and FEM Calculations
Authors: Zybill Christian , Schubrikoff Erich , Goryany Vyacheslav , Hinnemann Michael , Buch Johannes
Published: September 2014

A stress analysis for cast compound rolls is presented. Stress is divided into components as residual stress, stress implied by load, stress implied by torque, Hertz’ian contact stress and thermal stress. Furthermore, heat transfer is considered. Residual stress is measured and a 3D representation is given. All further stress components are calculated by FEM calculations. The data allow a complete description of the roll behavior in operation.
Dry Shearing of Micro-Alloyed Steels
Authors: Steinbach Frank , Güner Alper , Tekkaya A. Erman
Published: September 2014

In the production process of sheet metal parts, oil is widely used as lubricant, not only in sheet metal forming but also in shearing and blanking. Due to environment, health and cost reasons, the absence of lubricants is an aim for future production as it has initiated for machining in the last years. For lubricant-free shearing, it has to be known if there is an influence on the process itself when using oil or not. To find this out, experiments are carried out with a small testing device installed in a tensile testing machine and a blanking tool installed in a servo press. With the small device it is possible to make a piercing process with a circle punch of 16 mm diameter. The blanking tool produces a larger cut part with different holes and open cuts. Without lubricant, there is no difference in the maximum shearing force for the small device while the stripping force is higher and the cut edge zones differs slightly. Using oil or not has a small effect on the force using the blanking tool.
Investigations on the Effect of Ultrasonic Vibration in Cylindrical Cup Drawing Processes
Authors: Kim Sang Woo , Lee Young Seon
Published: September 2014

This paper presents experimental and numerical investigations on the effect of ultrasonic vibration on cylindrical cup drawing processes of a cold rolled steel sheet (SPCC). An experimental apparatus to superimpose high frequency oscillation on deep drawing processes was constructed by installing ultrasonic vibration generators consist of piezoelectric transducer and resonator to the die. Conventional and vibration-assisted cylindrical deep drawing tests were carried out for various drawing ratios, and the limiting drawing ratio (LDR) was compared. In order to evaluate the contribution of ultrasonic vibration to the reduction of friction between tools and a material quantitatively, finite element analyses were carried out. Through a series of parametric analyses, friction coefficients which minimize the differences of punch load histories between the experiment and simulation were determined. The results showed that the application of ultrasonic vibration make for improving LDR by reducing the friction between tools and the material, effectively.