bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the Effect of Resin Content on Buckling of Laminated Composite Plates
Authors: Cheng Qi You , Huang Jian Ping , Ling Ai Min , Feng Zhi Zhuang
Published: October 2014

Aerospace applications of composites involve components that are relatively thin plate or shell like structures, thus requiring the consideration of buckling as one of the many possible failure modes. To study the effect of the resin volume fraction on stability of composites, a finite element method based on micromechanics and classical lamination theory has been established to compute buckling loads of simply supported symmetric laminated composite plates subjected to the load of in-plane axial compress and shear load, respectively. The analysis procedure includes a Micromechanical finite element analysis that predicts the elastic modulus of lamina and a finite element linear buckling analysis that predicts buckling load of the composite plates. Three kinds of resin volume fraction that are equal to 44 percent, 47 percent, and 50 percent respectively are considered. The results show that the resin volume fraction has obvious influence on the stability of composite plate. The plate exhibits a relatively large increase in buckling load, about 12 percent, when the resin volume fraction increases by 3 percent. It is finds that the bending stiffness that has an obvious influence on the stability is an incremental function of elastic modulus and cubic thickness. The elastic modulus will be decreased slightly with the increase of resin volume fraction. However, the thickness of the plates is proportional to resin volume fraction.
Hybrid Energy Storage System Used in the New Energy
Authors: Ma You Jie , Lu Hong Kun , Zhou Xue Song
Published: October 2014

New energy generation parallel operation is an effective way for large-scale development and utilization of new energy generation. The instability of new energy, however, can bring a series of negative influence to stability of power grid. Adjusting the power fluctuations of new energy generation, achieving real-time output stable control, is one of the key technologies of stable operation. The hybrid energy storage system, including lithium ion battery and super capacitor, can reduce the fluctuation effectively. Then it can make new energy generation steady run. In addition, it can reduce the volume, weight and cost of the energy storage system compared with the single battery or super capacitor energy storage.
Synthesis of Sponge-Like Material for the Extraction of Fluoroquinolones in Milk
Authors: Yang Xun , Han Ye Hong , Wang Li Hui
Published: October 2014

The new sponge material was prepared by the copolymerization of polystyrene and methacrylic acid. The polystyrene seed was prepared by two-step seed swelling polymerization. Scanning electron microscopy images showed that the sponge material were clumps with porous morphologies. The adsorption behaviour of the sponge material was analysed by detecting pefloxacin and enfloxacin in milk samples. Under the optimized conditions, good linearity was obtained in the range 0.05-10.0 μg g−1, with a correlation coefficient (r2) of ≥ 0.9991. The recoveries at three spiking levels ranged from 85.6 to 106.9% with relative standard deviations (RSDs) of ≤6.6%. The sponge material could be applied to the rapid screening of Pefloxacin and enfloxacin in complicated milk-product matrices.
Wearing Performances of Superfine Profiled Acrylic Fiber/Silk Interwoven Fabric
Authors: Wang Yu Jue , Xu Jian Feng , Shen Hong Wei , Jiang Ya Fen , Zhang San Xing , Lin Xue Liang , Zhang Hong Xia
Published: October 2014

Dralon superfine profiled acrylic interwoven with traditional spun silk .There are 9 kinds of interlaced fabric. We discussed that in same condition of finishing and fabric weave (3/1right twill),different picking shuttle between superfine profiled acrylic and spun silk have a impact on fabric performance of moisture absorption, air permeability, drape, crease recovery and warmth retention. The results showed that: fabric has better wearability when silk and acrylic picking proportion is 1:5(That is the content of acrylic is 61.16%).
Study on the Light-Proofness of Double-Layer Curtain Fabrics
Authors: Yu Di Mei , Fan Li Xia , Zhang Hong Xia , Zhu Chen Yan
Published: October 2014

To provide the technical support for developing the highly light-proof decorative fabrics. Based on the weaving rationale of jet-weaving technology of electronic dobby jacquard, 2 type of double-layer fabrics was designed from weft arrangement ration, fabric count and yarn type, then tested on related performance including light-proofness. This dissertation combines all results of the fabric performance tests. Designed with 140 ends/cm, 72 picks/cm, weft arrangement ratio 2:1:1, and FDY silk as weft yarn, the highly light-proof drapery fabrics can achieve soft texture, lustrous surface and excellent light-proofness, which can satisfy the customers.
Adsorption of Alcohols onto Zinc Selenide (ZnSe) Crystal Surface
Authors: Christy Alfred A.
Published: October 2014

Adsorption behaviour of ZnSe, a popular material used in the manufacture of crystals for total internal reflectance techniques was studied for the adsorption of alcohols from dichloromethane solutions using infrared spectrometry. A series of n-alcohols were used in this study. The results show that the integrated area for the hydrogen bonded OH stretchings decrease and suggests that there is a continuous adsorption of alcohol molecules onto the ZnSe crystal by breaking the hydrogen bonds between alcohol molecules in solution.
Development of a New Type of Metal Matrix for Porous Metal Bonded Diamond Grinding Wheels
Authors: Dai Qiu Lian , Luo Can Bin , You Fang Yi
Published: October 2014

In this paper, a new type of aluminum bronze was used to substitute for the traditional tin bronze as the bonding matrix of the porous diamond wheel. Effects of hot pressing sintering temperature, the amount of Al and Fe on the mechanical properties of aluminum bronze based bond were studied by means of orthogonal test. A new kind of pore inducer with spherical shape was chosen. Effects of pore inducer size and processing parameters on the pore morphology and the mechanical properties of the porous metal bonds and diamond composites were studied. Experimental results revealed that theTRSof the new type porous aluminum bronze based bond and diamond composites increased by 119% and 258% respectively compared to the traditional porous tin bronze based bond and diamond composites. Also, stronger bonding between the metal bond and diamond grits was observed.
Investigation of the Field Emission Stability of Sphere-Like Diamond Microcrystalline-Aggregates Films
Authors: Gao Jin Hai , Li Zhen , Zhang Wu Qing
Published: October 2014

The sphere-like diamond microcrystalline-aggregates were fabricated by microwave plasma chemical vapor deposition (MPCVD) method. The ceramic with a Ti metal layer was used as substrates. The fabricated diamond microcrystalline aggregates were evaluated by Raman scattering spectroscopy, x-ray diffraction spectrum (XRD), scanning electron microscopy (SEM). The field emission properties were tested by using a diode structure in a vacuum. A phosphor-coated indium tin oxide (ITO) anode was used for observing and characterizing the field emission. It was found that the sphere-like diamond microcrystalline-aggregates films exhibited good electron emission properties. The turn-on field was only 0.55V/μm, and emission current density as high as 11mA/cm2 was obtained under an applied field of 2.18V/μm for the first operation. After several cycling operations, the field emission tended to stable characteristics of current versus voltage. The stability evolvement and mechanism are investigated relating to microstructure of the sphere-like diamond microcrystalline-aggregates films.
Coaxial Poly (Phenylene Vinylene)/Carbon Nanotube Nanocomposites
Authors: Zhou Yi , Wang Xiao Ping , Li Wen Yi , Li Hui , Tian Ming , Wang Xia
Published: October 2014

Coaxial nanocomposites were prepared by in–situ chemical polymerization of 4– dibromomethyl–2,5–2–octyloxy phenylene in the presence of multiwall carbon nanotubes. The morphology, microstructure and thermal and electrochemical properties of the resulting nanocomposites were investigated by scanning electron microscopy, Fournier infrared spectroscopy, thermal gravimetric analysis and cyclic voltammetry. The results indicated that the nanocomposites with uniform core-shell structure exhibited higher thermal stability than neat poly (phenylene vinylene). Furthermore, energy storage ability of these coaxial nanocomposites as electrode materials for supercapacitor was evaluated.
Microwave Absorption of Double-Layer Absorber Based on Nanocomposite BaFe12O19/α–Fe and Nanocrystalline Alloy Fe0.2(Co0.2Ni0.8)0.8 Microfibers
Authors: Shen Hao , Shen Xiang Qian , Li Min , Liu Hong Bo , Wang Zhou
Published: October 2014

In this paper, the prepared nanocomposite BaFe12O19/α-Fe microfibers and nanocrystalline magnetic alloy Fe0.2(Co0.2Ni0.8)0.8 microfibers are used as absorbents in the double layer structure for microwave absorption. The double layer absorbers with a total thickness of 2.0 mm, in which various matching and absorbing layers are designed, and their absorption properties are estimated. The results show that the absorbers with the matching layer of nanocomposite BaFe12O19/α-Fe microfibers have a very high microwave absorption performance. The absorption bandwidth (the reflection loss (RL) less than-20 dB) reaches 5.8 GHz ranging from 12.2 to 18 GHz, and the minimum RL value is-61.2 dB at about 15.2 GHz with 0.9 mm matching layer and 1.1mm absorbing layer respectively.
Optimization of the Preparation Technology of TiO2 Nanotubes
Authors: He Yun Bing , Fan Hong Bo
Published: October 2014

As for the low yield and high consumption of electrolyte in conventional anodization for TiO2nanotubes, several schemes were proposed to optimize the unit yield. The anode surface area per unit volume of electrolyte and the homogeneity of the electric field are found to affect the unit yield of well-structured TiO2nanotube besides voltage, F-and water content, reaction time and temperature, etc. Experimental results show that the unit yield over the cylindric electrodes quadruples in comparison with conventional anodization, which is attributed to higher anode surface area and homogeneous electric field. And SEM image indicates that well-structured TiO2nanotube arrays are fabricated. Thus it can be concluded that the unit yield could be increased by the method proposed in this paper and that our work provides a reference for the bulk preparation of TiO2nanotube and the energy-saving and emission-reduction in the process.
Electromagnetic and Microwave Absorption of Nanocrystalline Alloy Fe0.2(Co0.2Ni0.8)0.8 and Nanocomposite SrFe12O19/Ni0.5Zn0.5Fe2O4 Microfibers
Authors: Li Min , Wang Zhou , Liu Hong Bo , Shen Xiang Qian
Published: October 2014

Magnetic nanocrystalline alloy Fe0.2(Co0.2Ni0.8)0.8 microfibers and nanocomposite SrFe12O19/Ni0.5Zn0.5Fe2O4 microfibers are used as the absorbents in the double-layer structure for microwave absorption. The double-layer absorbers with a total thickness of 2 mm consisting of Fe0.2(Co0.2Ni0.8)0.8 and nanocomposite SrFe12O19/Ni0.5Zn0.5Fe2O4 microfibers are designed, and their microwave absorption properties are predicted based on the electromagnetic parameter measurements. The results show that the double-layer absorber with the absorption layer of SrFe12O19/Ni0.5Zn0.5Fe2O4 microfibers and the thickness of 0.6 mm has the best microwave absorption properties, with the bandwidth ( the reflection loss less than −10 dB) of 7.3 GHz ranging from 10.7 GHz to 18 GHz, and the maximum reflection loss of −71.4 dB at 12.1 GHz.
High Performance Supercapacitors Electrode Derived from the Pine Needles
Authors: Wang Pei Yu , Zhang Guo Heng , Jiao Hai Yan , Zheng Xiao Ping
Published: October 2014

In this paper, Pine needles (PNs) were used to synthesize porous activated carbon by the carbonization and activation processes. The material for PNs were carbonized at 600 °C and activated at 800 °C(denoted as AC-800) show typical amorphous character, and display porous structures with high specific surface areas 2729 m2/g via XRD and BET measurements. As the electro-active material, AC-800 electrode exhibit ideal capacitive behaviors in aqueous electrolytes, and the maximal specific capacitance is as high as 286 F/g at the current density of 1 A/g. Furthermore, AC-800 electrode shows excellent electrochemical cycle stability with ~94 % initial capacitance being retained after 2000 cycles. The desirable capacitive performances enable the PNs to act as a new biomass source of carbonaceous materials for high performance supercapacitors and low-cost electrical energy storage devices.
First Principle Study on the Electronic Structure of Borides
Authors: Chai Yong Quan
Published: October 2014

This study utilizes accurate first principle method to conduct a comparative study on he electronic structure of multiple borides. State density of the borides is also summarized. It is found that lanthanum boride has special electronic structure characteristics. Therefore, it is presumed that there is high superconducting transition temperature (Tc) in lanthanum boride. This study is able to provide asignificant theoretical reference for further experimental research.
Study of Nucleation of CVD Diamond by DC Arcjet Method
Authors: Li Bin , Wang Ying , Zhang Qin Jian , Li Hong , Lu Fan Xiu , Shi Yan Chao , Li Jia Jun , Chen Guang Chao
Published: October 2014

Arcjet plasma enhanced CVD was used to grow diamond. Nucleation of diamond was studied at the early stage of growth cause. The micro-structural probes (transmission electron microscope (TEM), high resolution electronic microscope (HREM), selected area diffraction (SAD) and electron energy loss spectra (EELS) were used to characterize the nuclei. It was found that nuclei formed following the amorphous carbon formation. The critical nucleus size was deduced to be less than 20 nm. The growth of nucleus would form the network-like structure. The incubation period of nucleation was deduced as 6–8min under the condition of high concentration of CH4 in H2.
A Portable Human Skin Tester Based on Resistance and Capacitance Measurement
Authors: Yang Bin , Dong Yong Gui
Published: October 2014

A portable tester for accessing the electrical properties of human skin surface is reported. A pair of interdigital electrodes (IDE) that contact directly with the human skin, is used as the sensing element. The impedance of the sensing system is modeled as a resistance and a capacitance in series. A square wave signal is applied so that impedance of the IDE is measured in a charging/discharging way. The response voltages of the IDE at two excitation frequencies, 10 kHz and 600 Hz, are measured successively during one measurement cycle. Since the equivalent capacitance of skin performs different frequency-dependent property other than the resistance, their values can be resolved from the measured response voltages. A microprocessor-based system is implemented as a prototype battery-powered portable unit for household measurements. Good repeatability and satisfied accuracy have been obtained by experimental results.
Ultrafast Dynamics of Sub-Wavelength Periodic Surface Structuring during Femtosecond Laser Processing of Dielectrics
Authors: Yuan Yan Ping , Chen Ji Min , Liu Fu Rong
Published: October 2014

A femtosecond laser pulse duration is shorter than many physical/chemical characteristic times, which makes it possible to control electron dynamics such as ionizations and electron densities. This study expermetally investigtes the effects of laser fluence on sub-wavelength periodic surface structuring based on ultrafast laser electron dynamics control. A quantum model for the sub-wavelength periodic surface structuring is also proposed, which considers both the wave properties in the photon particle-properties based plasma model for photon-electron interactions and transient localized changes of material properties. It shows that the laser fluence strongly affects the ablation crater shapes. The prediction of ablation crater shape and periodicity is in agreement with experimental data.
Analysis of Defect Modes in One-Dimensional Photonic Crystal with a Dielectric-Superconducting Pair Defect
Authors: Gao Jin Xia , Wu Ji Jiang
Published: October 2014

One-dimensional dielectric photonic crystals (PCs) with complex substitutional defect layers, consisting of superconducting (SC) and dielectric sublayers are theoretically studied. The influence of the incidence angle on the photonic gap spectra is theoretically analyzed. The pronounced difference in the transmittivity spectra of the PCs with right-handed (RH) and left-handed (LH) positions of the superconducting defect sublayer with respect to the dielectric defect sublayer is demonstrated. It is observed that, for the case of RH SC defect sublayer, the position of the defect mode and the transmittivity at the defect mode frequency strongly depend on the thickness of the superconducting sublayer as well as on the temperature. But the defect modes of the PCs with LH SC defect sublayer are nearly invariant upon the change of the thickness of the superconducting sublayer and the temperature.
Photo-Aging of Coating Based on Mixture of TDI and N75
Authors: Tan Jian Hong , Zhang Sheng Tao , Xiang Bin , Wang Shi Qin , Zhang Guo Qing
Published: October 2014

The photoaging of coating based on toluene diisocyanate (TDI) and N75 was investigated though artificial light exposure. The properties of studied polyurethane coatings, such as film gloss loss and discoloration were examined at some aging interval. In addition, scanning electronic microscopy (SEM) and Fourier transform infra-red spectroscopy (FTIR) were used to measure the morphology and chemical change of coatings before and after exposed under UV light. It was found that the addition of N75 had a significant effect on the discoloration of polyurethane coating. Furthermore, SEM images showed that greater degradation occurred in the coating without N75. These findings were also supported by the results obtained from FTIR analysis and gloss loss. The above results suggested that a mixed curing agent system with a mass ratio of TDI to N75 between 5:5 and 3:7 be a possible substitute of pure N75 for weather resistance PU coatings.
The Application of Optical Emission Spectrum in Copper Film Deposition by RF Magnetron Sputtering
Authors: Li Jia Jun , Shi Yan Chao , Liu Hao , Chen Guang Chao
Published: October 2014

Optical Emission Spectrum (OES) was utilized to monitor the deposition procedure of copper film byradio frequency (RF) magnetron sputtering.The plasma was found to contain Ar, Ar+, Cu and Cu+ when Argon was the working gas. The OES intensity of each composition increased with the increase of the input power of sputtering. Furthermore, intensity of Cu was higher than that ofAr, Ar+ and Cu+. The mechanical property of as-deposited Cu film was measured by scratch test method. It was found that with the increase of the input power, the adhesion strength possessed the maximum value while the square resistance decreased and surface roughness obviously. Theory calculation shows these properties were connected to kinetic energy of atoms in the plasma.
Preparation of Hollow Nickel Ferrite Microspheres and their Magnetic Properties
Authors: Li Jing Jing , Zhao Yun , Li Han Sheng , Wu Qin , Jiao Qing Ze
Published: October 2014

Hollow nickel ferrite microspheres with a diameter of about 1.5 to 2.5 μm were synthesized using an emulsion-based solvothermal method in combination with calcination at 550°C. The structures and morphologies of the nickel ferrite microspheres were characterized using an X-ray diffractometer, a transmission electron microscopy and a field emission scanning electron microscopy. Magnetization measurement was carried out using a vibrating sample magnetometer at room temperature. The saturation magnetization and coercivity of nickel ferrite microspheres could reach 19.41 emu/g and 202.28 Oe, respectively. Hollow nickel ferrite microspheres might be used as catalysts, magnetic materials and microwave absorbers.
Study on Design and Mechanism of a New Invisible Cloak for Visible Light
Authors: Zhao Jing Bo , Yao Hong , Jiang Juan Na
Published: October 2014

In order to realize the macroscopic objects invisible in the visible region, according to the law of refraction, total internal reflection law and symmetry reduction transformation method, a new type of visible light stealth cloak was designed. The cloak was prepared using the ordinary homogeneous and isotropic glass materials, which can guide the light around the hidden region, and the direction of propagation of light has not changed. Thus the macroscopic object achieve the perfect stealth. The invisible cloak in air environment for arbitrary polarized visible light have stealth features, easy processing, low cost, has potential application value.
Synthesis and Copper Sorption of Chestnut-Shell-Pigment/SiO2 Composite
Authors: Su Ping , Zhou Mi , Qi Jian Hua , Kan Huan , Yao Zeng Yu
Published: October 2014

The chestnut shell pigment/SiO2 composite was prepared by co-precipitation and thermal insolubilization and used to remove Cu (II) from water. The effect of the ratio of chestnut-shell-pigment to SiO2 on the removal efficiency was studied. The sorption experiments were examined by batch method. The optimal initial pH of the copper solution ranges from 4 to 6. The equilibrium data were fitted with the Langmuir than the Freundlich, and the sorption mechanism of Cu (II) suits to the former. The maximum sorption capacity derived from the Langmuir was found to be 18.87 mg g−1. The composite behaves an excellent potential for copper removal.
Preparation and Performance Study of Li1.02(Fe0.8Mn0.2)PO4/C by Ti Doping
Authors: He Rui , Liu Zhen Fa , Zhang Li Hui , Zhang Yan Liang
Published: October 2014

Ti dopping Li1.02(Fe0.8Mn0.2)PO4/C (Ti=0.01,0.03,0.05,0.07) was prepared by high temperature solid-state method ,with LiH2PO4, LiCO3, FeC2O4.2H2O , Mn (CH3COOH)2.4H2O TiO2 as raw materails. Glucose (C6H12O6) as carbon soures join in the mixture when ball milling. The structure and morphology of the samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). CHI660B electrochemical workstation was used to study the electrochemical performance of cathode material. The well-crystallized LiFePO4/C composite with homogeneous small particles was obtained after reacting at 700°C for 10h.
Effect of Freeze/Thaw Cycles on the Physical Properties of Selected Building Stones
Authors: Pavlík Zbyšek , Fořt Jan , Pavlíková Milena , Žumár Jaromír , Černý Robert
Published: October 2014

Effect of climatic loading on the physical properties of three different kinds of sandstone is investigated. The studied materials were used for masonry and ornamental parts of historical buildings over a long time period.The application of sandstone for building construction in the Central European region can be traced to the 14thcentury and ends in the 19thcentury, where the static function took over reinforced concrete. The samples of researched sandstones are exposed to the freeze/thaw cycles and the effect on materials performance is evaluated using measurement of several physical parameters. On the basis of obtained results, the materials behavior at real service conditions can be assessed, which is a necessary information for their practical usage in the reconstruction works on the historical monuments.
Palladium Supported on Mesoporous Silica via a Two-Step Method as an Efficient Catalyst for Suzuki-Miyaura Coupling Reactions
Authors: Wang Pei Yu , Zhang Guo Heng , Jiao Hai Yan , Zheng Xiao Ping
Published: October 2014

In this paper, palladium-containing SBA-15 (Pd/SBA-15) was synthesized via a two-step method. In this procedure, Pd nanoparticles of 3-5 nm in size have been synthesized by formalin reduction method and incorporated into mesoporous SBA-15 silica during hydrothermal synthesis. The resulting nanocomposite with 1.20 wt% Pd loading was achieved with highly dispersed and uniform palladium nanoparticles. The catalytic activity of the Pd/SBA-15 nanocomposite was used as a catalyst for the Suzuki-Miyaura coupling reactions. The Pd/SBA-15 nanocomposite exhibited excellent catalytic activities and reuse ability in air for the Suzuki-Miyaura coupling reactions.
Application of the CBR Method for Adding the Design Process of Module Manipulators
Authors: Ociepka Piotr , Herbuś Krzysztof , Gwiazda Aleksander
Published: October 2014

The paper presents the method basing on engineers knowledge and experience for aiding the process of designing module manipulators. The method, proposed by the authors, is based on the CBR method (Case Based Reasoning). CBR is a method of problem solving that bases on the searching for analogies (similarities) between a currently solved design task, and earlier cases, that adequately described, are stored in a computer memory. The paper presents the algorithm and formalized description of the developed method. It has been also presented its scope, and method of functioning are illustrated on the example of the designing module manipulators.
Performance and Differential Costs Analysis in a Two Echelons Repair System with Infinite Servers Queues
Authors: Ferreira Manuel  Alberto M. , Filipe José António , Coelho Manuel
Published: October 2014

Using infinite servers queues systems parameters, focused on its busy period, the performance and the differential costs of a two echelons repair system are analyzed through a model constructed with this goal. This kind of repair systems may be useful, for instance, in the operation of a fleet either of aircraft, or of shipping or of trucks
E-Commerce and Intelligent Agents in Virtual Enterprises
Authors: Coroiu Adriana Mihaela
Published: October 2014

Intelligent agents have an important role when we are talking about a virtual enterprise. Its role has been widely discussed over the years. Electronic commerce has been gaining momentum and is already quite popular among common consumers. The paper tries to combine these ideas and develop other aspects that arise from here. The tests and the simulation results show what and how can be some consequences related to e-commerce, with direct implications of intelligent agents in a virtual enterprise.
Energy Efficiency Process for Manufacturing Crank Shaft
Authors: Park Hong Seok , Nguyen Trung Thanh
Published: October 2014

Increasing energy efficiency of the manufacturing process is one of the solutions to resolve the ecological issues, save manufacturing cost, and reduce environmental impacts. In crank shafts manufacturing process chain, the potential of energy saving is great due to the induction heating line and heat loss from the process. This paper proposes the method to increase energy efficiency of induction heating line which spends most of the energy in a whole crankshaft manufacturing process. To reduce the heat loss from work piece, an insulating system was designed through the analysis of heat flow. The optimization of the heating parameters was done based on the simulation model with the multi criteria optimization method. In addition, this work also addresses a concept of holistic optimization approach to decrease energy consumption in the manufacturing process of crankshaft. The optimization approach in conjunction with design of experiment, analytical method, regression, and the robust optimization algorithm was applied in order to systematically optimize manufacturing processes. The optimization process aims to identify significant process parameters, determine potential solutions, and obtain optimal parameters. The energy flow of sub-process, including heating line, shearing, and forging is carried out in terms of a holistic approach, i.e. in consideration of the interrelationship between energy consumption and relevant criteria (cycle time, manufacturing costs, product quality). The optimized results show that the induction heating line can increase 14.8% in energy efficiency, of which 9% is due to the effect of insulating cover and 5.8% is due to process parameter optimization and the forging process chain can reduce approximately 10% in energy consumption. This paper contributes to improve the energy efficiency of the crank shafts manufacturing process.
Comparison of Long-Term Ageing Duration of Binary Ag-Cu Alloys
Authors: Labisz Krzysztof
Published: October 2014

Silver alloys, due to its specific properties are widely used in different branches of industry, with approximately 95% of the world silver production is used in the photographic industry and for jeweller production. Moreover Poland is a significant producer of silver in the world, and takes the 6th place on the list of the world's silver producers with the KGHM Polish Copper Company production on the first place among global companies providing silver on the market, with an annual production at 1281 tones. Because of this impotent role of silver, this work presents microstructure and mechanical properties investigations results of the long aged Ag-Cu alloys used mainly for mint monetary production. The purpose of this work was to determine the microstructural changes after 32 and 40 year of natural ageing time, with appliance of transmission electron microscopy as well as light microscopy. A very important issue - one of the investigations directions is also the possibility of study of spinodal decomposition process, which occurred in this alloy. After the long-time ageing of the material, there are detected morphological different areas of the Ag-α and Cu-β phase. As an implication for appliance in real conditions - as coin metal, or in electronic and chemical industry branches, there is the possibility of application of long term ageing for mechanical properties improvement by natural ageing method. Some other investigations should be performed in the future, but the knowledge found in this research shows an interesting investigation direction, where a low cost but long term treatment operations can be applied.
Influence of the Degree of Cold Drawing on the Microstructure and Properties of Pipes Used for Dampers
Authors: Simion Petru , Istrate Bogdan , Munteanu Corneliu , Dia Vasile , Avram Petru , Imbrea Marius Stelian
Published: October 2014

Dumpers are the main components of the suspension system with vertical oscillations role in the absorption of the automobile. The combination of suspension coil with dumper is forming the main body of the suspension system. Shock absorber pipe is mainly used for production of motorcycles, cars (sedan) car shock absorber, is the size of the relatively high precision seamless pipe products, its manufacturing costs and lower selling prices relatively seamless, with excellent cost performance, got the car and motorcycle manufacturing industry recognition, are gradually replacing the use of seamless pipes in the area.
The cold work process of pipes drawing consists of reducing the cross-section of a pipe by pulling the pipe through series of conical dies. The metal pipe drawing technology has been widely used to manufacture fine pipes. The influence of the degree of cold drawing on the mechanical properties of the carbon steel material were studied using the tensile test and hardness test experiments in order to replicate the service condition of the pipes used for automotive dumpers. Microstructure analysis were perfomed using optical analysis on a LEICA 5000DMI microscope up to 1000X magnitude and SEM images with a dual beam QUANTA 200 3D FEI SEM scanning electron microscope. The purpose of the work is to observe the main effects of the degree of reduction at different gradations by analysing the microstructure and mechanical proprieties behavior. The study used the stress-strain relationship of the tensile test experiment to study the effect of the degree of cold-drawing deformation on the yield strength and tensile strength properties of the dumpers used in automotive industry. The toughness of the low carbon steel used for the dumper manufacture reduces as the degree of drawing deformation increases. The ductility of the material also reduces with increasing degree of rawing deformation. The yield strength of the material was observed to reduce with increasing degree of cold-drawing, an indication of reduction in the ductility and the tensile strength of the material reduced with increasing degree of cold-drawn deformation. After high degrees of cold deformation by drawing, the hardness proprieties are increasing highlighted by cold-straining.
Cladding of Inconel 625+WC Composite Coatings Using a Direct Diode Laser
Authors: Janicki Damian
Published: October 2014

In the present study, a high power direct diode laser (HPDDL) was used to deposit composite coatings consisted of Ni-based superalloy Inconel 625 matrix and of WC reinforcement particles with a volume fraction of 60%. The influence of parameters, such as laser power beam (heat input) and WC particles size in the cladding powder on the coatings microstructure and erosion wear properties was investigated. The coatings were examined by optical metallography and scanning electron microscopy. The results showed that direct diode laser cladding provides non-porous coatings with homogeneous distribution of WC particles and very low degree of WC dissolution during cladding process. Erosion resistance of the composite coatings decreases with the size of WC particles decreasing.
Friction Studies over Idlers Sprayed with Al2O3 Powder Using Athmosferic Plasma Spraying Method
Authors: Avram Petru , Istrate Bogdan , Imbrea Marius Stelian , Lozneanu Marian Vasile , Paulin Constantin , Munteanu Corneliu
Published: October 2014

In military and mining industry are many machine elements – in our case idlers (for tanks, conveyors, and any others machineries which are using transmissions system which are subjected of coverage with low friction proprieties powder. These machine elements (idlers) must have low friction coeficient, because the functionality of the entire transmissions systems depends on them. Also the maintenance costs are very high, that is why we proposed to studies how to improve the performances of this machine elements. Researches in surface engineering allow the obtaining of new systems of materials by coating the basic material surface with other material having superior friction properties. In order to improve the machine elements durability, wear resistance, friction, we proposed to obtain a new system of materials using Atmospheric Plasma Spraying – with Sulzer 9MCE equipment. We have chosen the steel type 34CrNiMo6, MOCN class, STAS 691 - 880 as basic material and we coated it with Al2O3 powder. We made the samples and we tested them. The analysis has been made with Tribometre, which produces some data which link us to a low friction coeficient. The Al2O3 coating deposited on steel substrate is uniformaly deposited on the based steel, and need to be polished to decrease the friction coeficient. The results showed that the new material has a better microstructure than the basic material and its physical and mechanical properties have been improved.
Characteristics of Hybrid Coating Deposited by PVD and PACVD Process
Authors: Lukaszkowicz Krzysztof , Galeja Justyna , Paradecka Agnieszka , Borylo Paulina
Published: October 2014

Deposited on hot work tool steel substrate coating system composed of AlTiCrN film covered by diamond-like carbon (DLC)-based lubricant, was the subject of the studies. The AlTiCrN and DLC layers were deposited by PVD lateral rotating ARC-cathodes (LARC) and PACVD technology on the X40CrMoV5-1 respectively. This paper provides an analysis of the microstructure, mechanical and tribological properties. Several surface sensitive techniques and methods, i.e. High Resolution Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM), Raman spectroscopy and ball-on-disk were used to performed study of the coating. TEM investigation shows an amorphous character of DLC layer. It was found that tested AlTiCrN layer has nanostructural character with fine crystallites. In sliding dry friction conditions the friction coefficient for the investigated elements is set in the range between 0.02-0.04. The investigated coating reveals high wear resistance. The coating demonstrated good adhesion to the substrate.
Study Concerning the Cutting Tool Wear at Drilling of the Stainless Steel X20Cr13
Authors: Vlase Aurelian , Iacob Marius , Blăjină Ovidiu , Darie Vlad
Published: October 2014

The researches in the cutting domain have as purpose the cutting process economic optimization. This paper studies the cutting tool wear at drilling of the stainless steel X20Cr13. The experimental data and their subsequent processing represent the original contribution of the authors to the estimation of polytropic exponents and to the assessment in terms of structure of the calculus relation of the cutting tool wear. The obtained relationship of the cutting tool wear on the tool putting surface at drilling of the steel X20Cr13 permits the determination of the wear on the putting surface, in the case of a couple: stainless steel X20Cr13 - Rp5 high-speed spiral drill, depending on the work parameters and the cutting conditions. Putting the condition of wear limitation, from the obtained relation, the cutting speeds are exactly given. The paper also contains graphs for the variation of the tool wear with parameters of the cutting technology. The results can be taken into consideration in the educational studies and in the theoretical technical research. They can be implemented in the manufacturing activity.
Study about the Calculus Relation of the Cutting Moment at Widening of the Stainless Steel X20Cr13
Authors: Blăjină Ovidiu , Iacob Marius , Vlase Aurelian , Darie Vlad
Published: October 2014

This paper studies the cutting moment at widening of the stainless steel X20Cr13. The structure of the cutting moment relation was modified with respect to the relation available in the technical literature for common steels. The tool speed was included in the calculus relation. The experimental data and their subsequent processing represent the original contributions of the authors to the estimation of polytropic exponents and to the assessment in terms of structure of the calculus relation of the cutting moment. The paper also contains graphs for the variation of the cutting moment with parameters of the cutting technology. The graphs are drawn based on the analytic relationship of the cutting moment, obtained in the paper, using the mathematical software Maple. The results presented in this study can be taken into consideration in the educational studies and in the theoretical technical research. Also, they can be readily implemented in the manufacturing activity. Our further studies aim these problems for another steels classes.
Microwave Differential Thermal Analysis Technique of the Fe2O3+BaCO3 Homogeneous Mixture
Authors: Savu Sorin Vasile
Published: October 2014

The microwave differential thermal analysis (MW-DTA) is a new procedure to evaluate the materials, barium ferrite type M in this paper, according to the phenomena appeared during the material heating. The paper presents a new evaluation technique which is faster and with low energy consumption. The microwaves are used to heat the material, two infrared pyrometers for monitoring the temperatures on the material surface and a temperature regulator where the data are recorded for evaluation. The material, a homogeneous mixture of Fe2O3+BaCO3, is a ceramic material with good absorbance properties, so the heating will be pure microwave heating. The results and the DTA graphic is automatically generated by the temperature recording device based on the data sensed by the infrared pyrometers. The paper presents technical aspect regarding to the microwave heating and temperature measurement in microwave field and how to make differential thermal analysis in microwave field.
Comparative Study Concerning the Generation of some Circular Grooves by Cold Rolling with Wedge Tools and Cutting
Authors: Iacomi Doina , Iordache Daniela Monica , Nitu Eduard Laurentiu
Published: October 2014

The economic context and the current guidelines of research and achievement of complex profiles are focussed on choosing that process which leads to obtaining high quality pieces with minimum costs. Circular grooves are complex surfaces often encountered on pieces in machine construction. They can be processed either by cutting or by cold plastic deformation.
This paper presents by comparison a series of characteristics of a circular profile obtained by two different processes: profiled turning with radial feed and cold rolling with two wedge tools. The characteristics analysed refer to the roughness of the profile obtained, the microstructure and micro-hardness of the superficial layer generated. In the experiments two types of materials with different compositions and properties were used: cementing steel AISI 1015 and improving steel AISI 5140, usually used for the construction of pieces with circular grooves. Processing by rolling was performed with two types of wedges: with a long area of deformation and low slope angle and with a short area of deformation and high slope angle.
The results of the study allow establishing the conditions to apply each one of the two processes analysed, highlighting their advantages and disadvantages, as it results from the comparison of the characteristics of the profile obtained.
The Influence of the Blank Holder Force on Material Thinning during Forming of a Rectangular Part Made from Tailor Welded Blanks
Authors: Albut Aurelian , Ciubotariu Vlad Andrei
Published: October 2014

The current work deals with numerical simulation connected to forming of a rectangular shaped part made from tailored blanks, having the welding line positioned symmetrical with respect to the part geometry. The objective was to study the relation between the blank holder force applied during forming and the thinning of the parents materials. All the parameters are fixed except the blank holder force, its variation will cause variation of the material thinning. The presented work is trying to demonstrate the important role of the blank holder force on the material thinning during the deep drawing process. It must be mentioned that both materials from the welded structure are having the same thickness (1mm). The Dynaform 5.8.1 software is used to simulate the forming process. The part obtained after each simulation is analyzed and measured to quantify the on the material thinning. All the parameters are maintained fixed except the blank holder force. The obtained results for five different binder forces (5, 10, 30, 50, 70 kN) were compared to realise the behaviour of the tailor welded blanks during deep drawing process. In the final part of this paper conclusions regarding the influence of the blank holder force on the material thinning are presented.
The Method of Substitutive Circles Family: Application in Catia Design Environment for Gear Shaped Tool Profiling
Authors: Berbinschi Silviu , Frumuşanu Gabriel Radu , Teodor Virgil Gabriel , Oancea Nicolae
Published: October 2014

Tools which generate by enveloping using the rolling method may be profiled using various methods. The substitutive circles family method is a complementary method developed based a specifically theorem, in which is determined a family of circles associated with the blank’s centrode, family which envelop the profile to be generate. The method assumes the determination of the circles family, transposed in the rolling process between the blank and tool centrodes. In this paper is proposed an algorithm for curling surfaces in enveloping, associated with a pair of rolling circular centrodes. The graphical algorithm is based on the representation of the circles family enveloped the blank’s profile. It is generated the circles family transposed on the centrode associated with the gear shaped cutter and is determined a new position of contact points with the blank. The assembly of these points forms the profile of the gear shaped cutter. The numerical data proof the proposed method quality.
Spiroid Gear with Composite Profile of the Worm – Hob Mill Tool
Authors: Totolici Sofia , Teodor Virgil Gabriel , Baroiu Nicuşor , Berbinschi Silviu
Published: October 2014

The spiroid gears are known and used due to their performances: increased gear ratio; reduced overall dimensions; the simplicity of the construction; increased carrying capacity on the gear flanks etc. The gears construction demand assurance of a certain geometry of the worm, which constitutes, in the same time, the basics for the generating tool of the spiroid wheel. In this paper, a worm with a composite profile is proposed. The profile is composed by an assembly of circles arc, in order to increase the length of the flank active zone. This design is intended to increase the contact length between the flanks of the spiroid worm and spiroid wheel, in order to decrease the contact pressure between the two parts and to improve the gear function process.
Structure and Properties of the Aluminium Alloy AlSi12CuNiMg after Laser Surface Treatment
Authors: Tański Tomasz , Dobrzański Leszek Adam , Pakieła Wojciech , Labisz Krzysztof , Roszak Marek , Tomiczek Błażej
Published: October 2014

The investigations results concern the influence of laser heat treatment on the structure and mechanical properties of aluminium alloy, where the mutual relationships were tested and presented in this paper. The aim of this investigations was to improve the mechanical and wear resistance properties of the top surface layers of the aluminium alloy AlSi12CuNiMg by remelting and feeding the tungsten carbide powder in to the molten material and next quick solidification. The powder of tungsten carbide has been introduced in the liquid metal using gravity feeder at a constant rate of 3 g/min. In order to remelting the aluminium alloy surface, there has been used the high power diode laser HPDL, with an applied power of the laser beam in the range between 1.6 kW and 2.0 kW. The linear laser scan rate of the beam was set as much as 0.4 m/min. As a result of laser treatment of aluminium alloy a composite layer with higher hardness and enhanced wear resistance compared to the base material has been obtained.
Mechanism of Laser Surface Modification of the Ti-6Al-4V Alloy in Nitrogen Atmosphere Using a High Power Diode Laser
Authors: Lisiecki Aleksander
Published: October 2014

The influence of the nitrogen content in argon/nitrogen gas mixture on mechanism of titanium nitrides formation during laser surface processing of titanium alloy Ti6Al4V with high power diode laser was investigated. The phase composition and microhardness on cross-section of surface layers were analyzed and described. It was found that the nucleation of TiN dendrites in nitrogen rich atmosphere (at least 75 % of N2) takes place on the liquid/gas boundary as a result of the reaction between molten titanium and gaseous nitrogen. The subsequent growth of titanium nitride dendrites (crystallization) proceeds into the liquid metal (weld pool), perpendicularly to the top surface. High length of the titanium nitride dendrites up to 180÷250 μm in the surface layer produced in pure nitrogen atmosphere indicates also very rapid rate of dendrites growth in the molten titanium. The tendency to form titanium nitrides during laser surface processing of the investigated titanium alloy falls dawn with the decrease of nitrogen content in the gas mixture.