bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Characterization of Inorgano-Organo-Montmorillonites and its Adsorption Capacity for Phenol in Water
Authors: Ren Guang Jun , Sheng Kai
Published: November 2010

On condition that OH- / Al3+ molar ration was 2.4, inorgano and inorgano -organo- montmorillonites was synthesized by titrating Na-montmorillonite with hydroxyl aluminum solution. From powder XRD data, it was shown that the interlayer of montmorillonites was increased to 1.9 nm and over. The adsorption of Phenol by four modified montmorillonite samples was also studied and the results showed that the adsorbability of inorgano-organo- montmorillonites was much better than Na-montmorillonites. The adsorption dynamics follows the laws of Bangham and Langmuir. The relation between adsorbing quantity(qe ) and equilibrium concentration (Ce )tallies with the isothermal adsorption equations of Freundlich and Langmuir.
Study on Surface Quality of Lead Clad Tin Bimetal Continuous Casting by Air Pressing Core-Filling
Authors: Liang He , Zhao Yong Long , Zang Bo Lin , Liu Zhu , Liu Zeng Hui , Wu Chun Jing
Published: November 2010

To provide theoretical basis and practical guidance of preparing copper clad aluminum composite rods by directly continuous casting, low melting point materials of lead and tin were selected to prepare composite rods of external diameter Φ12mm and inner diameter Φ8mm through adopting air pressing core filled continuous casting processing. The orthogonal tests consisting of three factors of melting lead temperature, continuous casting speed and inflation pressure at three different levels were designed to obtain arrangements of optimal process parameters that affected surface quality of bimetal casting rods in principle. The experiments showed that composite rods have excellent surface quality under the condition of melting lead temperature,375 , continuous casting speed, 10 mm/min, and inflation pressure, 0.03MPa.
Stress Analysis and Formability of Sheets in Semi-Ball Bottom Cylindrical Deep Drawing
Authors: Chen Kang , Zhou Tao , Peng Cheng Yun , Chen Yuan Fang
Published: November 2010

Semi-ball bottom cylindrical deep drawing is different from the traditional deep drawing, since it is not only characteristics of traditional drawing, but also of bulging. According to the semi-ball bottom cylindrical deep drawing features, the stress conditions of the sheet in different regions have been analyzed by a mathematical modelling. In addition, the effects of processing parameters on the forming limit of the sheet in semi-ball bottom cylindrical deep drawing have been investigated by experimental method and simulation based on dynaform, respectively. It is found that the experimental results are consistent to that in simulation and the results show that the formability of the sheet is influenced greatly by the blank holder force, friction coefficient and thickness. With the blank holder force and friction coefficient decreasing and the thickness increasing, the bulging area can be expanded, which is beneficial to the improvement of the forming limit height of the semi-ball bottom cylindrical deep drawing parts.
Magnetic Field on Properties of Solid Lubricants Coating on High-Speed Steel Surface
Authors: Hou Suo Xia , Jia Xiao Ming , Wu Chao
Published: November 2010

The main factors that affect properties of solid lubricant coating on high-speed steel surface are the surface roughness and the weight of phosphate coating. The effect of magnetic field on high speed steel phosphate process is significant. It promotes the film and the different appearance and composition of the film. Because the ferric phosphate and dihydric phosphate in phosphate solution may be ordered arrangement by additional magnetic field, they can be deposited on metal surfaces quickly. That is to say that a certain intensity of the magnetic field can reduce the entropy of the phosphate processing system and speed up the formation of phosphate film. During phosphate treatment, the friction performance of high-speed steel coated with solid lubricant coating was significantly improved.
Preparation and Properties of Thin Walled Copper Tube by a Short Process Method
Authors: Yuan Bao Long , Wang Zi Dong , Li Xiang Ming , Wu Chun Jing
Published: November 2010

Thin walled copper tube is prepared in vacuum melting and argon protecting continuous unidirectional solidification equipment by a short process method. The size of the thin walled copper tube is ф39×1.8 mm. The effect of process parameters on the solidification structure and the surface quality of the thin walled copper tube is investigated. The mechanical properties and electrical properties are tested and analyzed. The results show that the thin walled tube with columnar crystal structure and good quality surface can be obtained continuously and stably under the most appropriate process of the melting temperature is between 1423K and 1453K, the cooling water volume is 0.2～0.5m3•h-1, the cooling distance is 50mm, the drawing speed is not higher 20m•h-1. The elongation can reach 60%, and conductivity can reach 102.6%IACS.
Study on Segmented Variable Blank Holder Force Method of Rectangular Box Drawing
Authors: Li Xi Ning , Jiang Cheng Yu , Wang Jian Ping , Wang Zhong Qi
Published: November 2010

The form of blank holder and the manner of blank holder force (BHF) on the complicated parts forming are very important. The blank holder of rectangle box forming was divided long straight segments, short straight segments and corners. The forming process simulation of rectangular box was conducted by FEM based on explicit algorithm, including single-piece blank holder with constant BHF, single-piece blank holder with variable BHF, segmented blank holder with constant BHF, segmented blank holder with variable BHF. The results were analyzed according to the thinnest level of the parts. The displacement in the Z direction of blank holder in the simulation was considered, and the method of determining segmented variable blank holder force (VBHF) was proposed. Finally rectangular box was obtained by rectangular box drawing system of segmented variable BHF on the basis of the simulation result.
Fatigue Failure of Silicon Nitride Ceramic Balls
Authors: Zhou Jing Ling , Chen Xiao Yang , Wu Guo Qing , Chen Jian Chun
Published: November 2010

Silicon nitride ceramic ball surface is examined after failure with scanning electron microscopy. The profile of the fatigue spalling takes the shape of an ellipse. The failure cause, fatigue phenomenon and mechanics are analyzed. The research shows that subsurface cracks play a dominant role in the formation of spalling failure. These cracks originated from volume defects of the material, and propagate, to form fatigue spalls under the action of principal tensile stresses. The contours of equal tensile stress of Oxy plane underneath surface are elliptical. Subsurface cracks are shape of ellipses and spall is also of the elliptic shape. The principal tensile stress increases with increasing contact load, causing spall formation and reduction of rolling contact life.
Morphology Control of PbWO4 Crystals in Formamide/Water Solution
Authors: Guo Guo Long , Wang Yan , Yang Xiao Long , Huang Jian Hua
Published: November 2010

PbWO4 crystals were synthesized by homogeneous precipitation in formamide (FA)/H2O solution, where the content of FA was found to play crucial role in the morphology of the final products. PbWO4 crystals with various morphologies, such as pagoda, tetra-bipyramid, and bundle of rods, were obtained with an increase of the content of FA. The products were characterized by XRD and photoluminescence measurements.
Study on Current Transform Features of Single-Molecule C60 Based on Band Theory
Authors: Jing Guo , Jun Qiu Cheng , Fang Liu
Published: November 2010

This single-molecule C60 system with two atomic lines as left input electrode and right output electrode is calculated by simulation using the Green，s function method based on the density function theory. The characteristics of current transmission of single-molecule C60 which include I-V curve, current-temperature changing and transmission spectrum are given. The resonant switching is shown from the single-molecule C60 transmission spectrum, differential negative resistance (NDR) and the high ratio of current peak and current valley are also indicated from the I-V curve. The conclusions can be explained using band theory very well and finally the impact of temperature for current of this C60 single-molecule system is discussed etc.
Criterion for Dendrite Fragmentation of Steel under Imposition of Linear Traveling EMS
Authors: Chen Jin , Su Zhi-Jian , Nakajima Keiji , He Ji Cheng
Published: November 2010

In the fragmentation theory of T. Campanella et al, the local remelting of dendrite arms is induced by the solute-rich fluid flow. Based on this theory, the effects of linear EMS intensity and solute content on CET of steel are investigated. The conclusions are as follows: The criterion for dendrite fragmentation under linear EMS is derived based on dendrite fragmentation theory by T. Campanella et al. And the criterion is verified with steel experiments. It is valid for steel under the Linear EMS. Investigation is carried out on relation between critical volume fraction of solid and solute content at the time of dendrite fragmentation (CET occurrence). It is concluded that critical volume fraction of solid is small with low EMS intensity and it decreases with the increase of solute content (C, Mn). The reason is that it causes that flow in the mushy zone becomes small which leads to CET occurrence difficult.
Finite Element Analysis and Optimization of Deformation Behavior for Spur Gear Warm Forging Process
Authors: Xu Shu Bo , Jing Cai Nian , Sun Ke Ke , Ren Guo Cheng , Wang Gui Qing
Published: November 2010

Recent years have therefore seen growing interest in gear precision forging to net-shape form of forge bevel, spur and helical gears, as an alternative to conventional manufacturing. In this paper, gear precision forging processes are simulated by using metal forming finite element code DEFORM-3D. The investigations of gear precision forging processes are conducted with perform forging and final forging processes. The processes of completely closed-die forging, moving-die forging and central divided flow forging processes are investigated for spur gears. The effect of different processes on the distribution of effective stress in the workpieces and forging loads are given. The purpose of this study is to introduce a new method, a so-called floating-relief method which applied to the forging of spur gears. It indicated that the flowing properties of the gear billet have a higher improve than that of conventional forging process. And the forging load obtained by using this new precision forging technology is decline sharply. The floating-relief method for gear precision forging is a sound process in the practical application.
Fabrication and Mechanism of Titania Nanotube Arrays by Anodization in DMSO Electrolyte
Authors: Zhao Jian Ling , Kang Ying Ru , Wang Xi Xin , Tang Cheng Chun
Published: November 2010

Titania nanotube arrays were synthesized via anodic oxidization of titanium foil in dimethyl sulfoxide (DMSO) solution containing 2 wt% HF and 3 wt% H2O at 40 V. The microstructure of the arrays was characterized with scanning electron microscopy (SEM). The results show that morphology of titania nanotube arrays is evidently influenced by the anodization time, and with the extension of oxidation time, the better morphology could be obtained. The possible formation mechanism of titania nanotube arrays has been discussed.
Effects of a InGaAs Strained Layer on Structures and Photoluminescence Characteristics of InAs Quantum Dots
Authors: Yao Jian Ming , Kong Ling Min , Wang Shi Lai
Published: November 2010

The influences of a thin InGaAs layer grown on GaAs(100) substrate before deposited InAs self-assembled quantum dots(SAQDs) were experimentally investigated. Scanning electronic microscope (SEM) measurements show that the InGaAs strained layer may release the strain between wetting layer and QDs, and then enlarge size of QDs. When the thickness of InAs layer is small, the QDs are chained. Temperature dependent photoluminescence (TDPL) measurements show that the PL peaks of InAs QDs with In0.1Ga0.9As show much more red shift compared with the QDs directly deposited on GaAs matrix, and PL integral intensity enhances as T rises from 50K to 90K. We attribute this enhancement to the small potential barrier between WL and QDs produced by the InGaAs stained layer.
Preparation and Characterization on Self-Catalytic of SnO2 Nanowire Junctions
Authors: Xu Xiao Yong , Wen Zhong He , Wang Xian Zhong , Xiang Yun
Published: November 2010

Multiple branched SnO2 nanowire junctions have been synthesized by thermal evaporation of SnO powder. Their nanostructures were studied by transmission electron microscopy and field emission scanning electron microcopy. It was observed that Sn nanoparticles generated from decomposition of the SnO powder acted as self-catalysts to control the SnO2 nanojunction growth. Orthorhombic SnO2 was found as a dominate phase in nanojunction growth instead of rutile structure; The branches and stems of nanojunctions were found to be an epitaxial growth by electron diffraction analysis and high-resolution electron microscopy observation. The growth directions of the branched SnO2 nanojunctions went along the orthorhombic [110] and [1—,10]. A self-catalytic vapor–liquid–solid growth mechanism is proposed to describe the growth process of the branched SnO2 nanowire junctions. Introduction
Study on Strip Winding Machine for Prestressed Cold Forging Die
Authors: Wang Qiang , Zhang Xian Ke , Wu Qian , Zhou Yue
Published: November 2010

The strip wound die for cold forging operation is prestressed by the thin high-strength steel strips, which is characterized by the strength that is twice or more than that of the conventional compound die, as well as the achievement of even higher stiffness. In this paper, a special strip winding machine is designed and developed to manufacture the prestressed strip wound die. The structure and function of this machine is described in detail. FEM study on the frame of the machine is carried out to prove the feasibility of the design. The total tension will be determined by the constant tension which is equal to the friction force generated by the clamping device, and the variable tension which is generated by the AC servo motor in the uncoiler device. Controlling strategy and the framework of tension controlling system are also presented.
Synthesis and Magnetic Properties of CoFe2O4 Nano-Particles
Authors: Chen Xiao Yun , Li Hua , Su Yue Zeng , Huang Zi Shan , Liu He Zhou
Published: November 2010

Spinel CoFe2O4 nano-particles were synthesized by hydrothermal traditionally and Ethylene Glycol (EG) assisted hydrothermal process originally. The effects of reaction temperatures from 140°C to 200°C, different OH- provider and EG/water ratio on the nano-particles’ structure, morphology and magnetic properties of composition were studied by X-ray diffractometer (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The possible mechanism for the effects on the properties was also discussed in details. The results showed that NaAC as OH- provider and higher EG/water ratio in solvent were benefit for getting smaller CoFe2O4 nano-particles. And existence of EG is also important to remove the α-Fe2O3 phase.
Wood-Polymer Composite Prepared by In Situ Synthesis of Copolymer within Wood and its Dimensional Stability
Authors: Li Yong Feng , Jiang Chi , Lv Duo Jun , Dong Xiao Ying , Liu Yi Xing
Published: November 2010

In order to improve the value-added applications of low-quality wood, a novel Wood-Polymer Composite was fabricated by in-situ synthesis of copolymer from monomers within wood porous structure. The structure was characterized with SEM and FTIR, and its dimensional stability was also tested. The SEM observations showed that copolymer filled up wood pores and contact tightly with wood matrix, indicating strong interactions between them. FTIR analysis indicated that when the monomers copolymerized in situ wood porous structure, they also reacted with wood matrix by reaction of hydroxyl groups and ester groups, indicating chemical bond between the two phases, which is agreement with SEM observations. The volume swelling efficiency and contact angle of such composite were higher than those of wood, respectively, indicating good dimensional stability involving volume swelling efficiency and contact angle. Such composite could be potentially applied in fields of construction, traffic and indoor decoration.
Water Permeability of Polyvinyl Alcohol (PVA) Fiber Reinforced Cementitious Composites
Authors: Liu Shu Guang , He Cun , Yan Chang Wang , Zhao Xiao Ming
Published: November 2010

The water permeability of cementitious composites containing polyvinyl alcohol (PVA) fiber, fly ash (FA) and silica fume (SF) is studied in this paper. The parameters studied include volume fraction of PVA fiber, cement substitution with fly ash and cement substitution with both silica fume and fly ash. The research findings show that with the increase of volume fraction of PVA fiber, the penetration depth of cementitious composites is decreased. The penetration depth increases with the addition of FA and SF. Conclusions were drew that PVA fiber, FA and SF have an obvious influence on the water permeability.
Preparation of EG-g-MWCNTs and Antistatic Poly(Ethylene Terephthalate) Nanocomposites
Authors: Wang Ruo Xi , Wang Hua , Tian Xing You , Yan Qing , Zheng Kang , Wang Lei
Published: November 2010

Antistatic Poly(ethylene terephthalate) (PET) materials had been successfully prepared through solution-blending incorporation of ethylene glycol-graft-Multi-walled carbon nanotubes (EG-g-MWCNTs). MWCNTs were first carboxylated and then esterified with EG to yield EG-g-MWCNTs. The FT-IR spectra, TEM images, Raman spectra, TGA curves and electrical conductivity were investigated, which indicated that the agglomeration degree of MWCNTs has been reduced and the conductivity keeps as high as 4.278 S/cm after the modification of EG. On the other hand, EG-g-MWCNTs dispersed well in EG, which was one of the synthetic monomers for PET, and thus ensured its good compatibility with PET. As a result, the electrical conductivity of PET/EG-g-MWCNTs nanocomposites (0.1 wt%) was seven orders of magnitude higher than pure PET and reached the antistatic level.
The Research on the Mechanical Property of CBF/PP Composite Board
Authors: Zhu Fei Fei , Zhong Zhi Li , Guo Zong Fu
Published: November 2010

The three composite boards which were made of continuous basalt fiber (CBF) and polypropylene fiber (PP) in different fiber ratios were researched on this paper. The manufacturing forming process included blending, carding, web formation, laminating and compression molding orderly. The tension and bending properties were investigated experimentally, and then dual variance analysis was used to show the significant difference of the mechanical property in the transverse and longitudinal orientation as well the appreciable impact of different fiber ratios to the mechanical property. The results show that the difference of the tension and blending strength in the same direction, among composite boards in different fiber proportions, is about 1~10Mpa; the difference in the same fiber proportion, between transverse and longitudinal, vary within a wide range from 10Mpa to 30Mpa. The results of variance analysis have also proved the conclusion, the difference between transverse and longitudinal is more significant than the difference among different fiber proportions. In the similar study, the significance hadn’t been seen sufficiently, so this paper provides reference to the actual application of the composite board.
Preparation and Properties of Al2O3 Ceramic Reinforced Mo-Based Composites by Al(NO3)3 Precursor
Authors: Xu Liu Jie , Wei Shi Zhong , Zhang Guo Shang , Li Ji Wen , Ma Xiang Dong , Dai Bao Zhu
Published: November 2010

To enhance the wear resistance of molybdenum alloys, Mo-based composites reinforced by Al2O3 ceramic particles were developed. Using Al(NO3)3 aqueous solution and MoO3 as raw materials, the Molybdenum powders mixed with Al2O3 particles were prepared by liquid-solid incorporation, drying, pyrolysis of Al(NO3)3 and deoxidation of MoO3 by H2. And then the Mo-based composites with 3-10vol.% Alumina were prepared by compaction and sintering at 1840°C. The morphology of the Molybdenum powder and microstructure of the composites were analyzed by SEM and XRD. The micro-hardness, density and wear property of composites were researched. The results showed that α-Al2O3 ceramic particles and Molybdenum matrix compose the composites. With the increase of Alumina content, the molybdenum powders become fine and rule, the grains of composites become fine, the microhardness of Molybdenum matrix increases, and the density first increases and then decreases. The friction coefficient of composite is scarcely affected by the alumina content. While the wear weight of the composite decrease with the increase of Alumina content. There are obvious plow furrow and abrasive dust on the worn surface, showing the abrasive wear characterization.
Preparation of Rigid Polyurethane-Imide Foams
Authors: Sang Xiao Ming , Chen Xing Gang , Hou Gui Xiang , Yu Shou Wu
Published: November 2010

A novel rigid polyurethane thermosetting foam is synthesized via the reaction of isocyanate terminated polyimide prepolymers with polyether polyol(4110), and deionized water and n-pentane are used for blowing agents simultaneously. The prepolymers and polymers are characterized by conventional methods and -NCO conversion rate, characteristic structure and morphology are also studied. The results show that the optimal condition of polymerization of polyimide prepolymers is under 60 oC for 30min. FTIR data show that the imide groups have been achieved successfully. The rigid polyurethane-imide foams prepared by this technique possess the cell diameter ranging from 1.5mm to 2.5mm and bubbles distributing equably.
Preparation and Test of Polyurethane Foam Composites with Alkali Lignin/Renewable PUF
Authors: Li Chang Yu , Liu Li Li
Published: November 2010

The polyurethane foam composite was prepared by alkali lignin and renewable polyurethane foam (PUF). The thermal stability as well as compression property was studied. It was obtained from the TG curve and the DTG curve that the initial decomposition temperatures of polyurethane foam composites with 10% renewable PUF and without renewable PUF were 560.25K and 574.13K,respectively, which showed the renewable PUF affacted the thermal stability of the polyurethane foam composite. The compressive strength (σ10)was from 203kPa to 125 kPa , which were affacted by the dose of the renewable PUF.
Mechanical Property Effect of Na2SO4 on Cement-Reclaimed Asphalt Pavement Mixture
Authors: Wang Hai Feng , Ma Bao Guo , Yin Xiao Bo
Published: November 2010

According to the system of asphalt pavement cold in-place recycling(APCIR), added proper Na2SO4 into different designed reclaimed asphalt pavement(RAP), the mechanical property effect of Na2SO4 on cement-reclaimed asphalt pavement mixture was studied. It showed that early strength of RAP rose with adding more Na2SO4. After adding Na2SO4, the strength of RAP in 5d would increase 12% than that RAP without adding Na2SO4, this technology will play the important role in asphalt pavement repairment.
Discovery of Zr-Al-Ca-O Phase in Zr-Al-Ca-O-N Composites and its Synthesis
Authors: Wang Rong Lin , Sun Jia Lin , Bu Jing Long , Wang Zhi Fa
Published: November 2010

Zr-Al-Ca-O-N composites were prepared in N2 atmosphere at 1600 oC with Ca-PSZ and AlN powders as raw materials. Zr-Al-Ca-O phase was synthesized in air atmosphere at 1600 oC with Al2O3, ZrO2 and CaO powders as raw materials. Phase constitution of these composites was investigated by XRD and EDS analyses. The results show that Zr-Al-Ca-O phase exists in Al-CaO-ZrO2-N2 systems ceramic and Zr-Al-Ca-O phase can be synthesized in air atmosphere at high temperature with Al2O3, ZrO2 and CaO powders as raw materials.
The Effect of the pH Value of Wood on the Curing Reaction of Low Toxic Urea-Formaldehyde Resin
Authors: Zhu Li Bin , Gu Ji You , Zhang Yan Hua , Shen Jun
Published: November 2010

The differential scanning calorimetry(DSC) was used to study the curing reaction of low toxic UF resin with poplar, birch, larch powder in different pH value. The results showed that the effect of different wood flour and its pH value on the curing reaction of UF resin was not the same. Along with the increase of the pH, the peak temperature and the onset temperature was raised; the peak temperature and the onset temperature of poplar was higher than that of the birch. The tempera- ture of the curing reaction of UF resin modified by melamine was higher than the UF resin without modification.
Development of IPMC Actuator for Flapping Motion of Dragonfly
Authors: Cheng Tai Hong , Xuan Dong Ji , Li Zhen Zhe , Shen Yun De
Published: November 2010

The Ionic Polymer-Metal Composites (IPMC) actuator as electro-active polymers is well known for the fast and flexible bending actuation in the electric fields. In this paper, the IPMC actuator is fabricated and designed for realization of biomimetic flapping motion of dragonflies. The resonant frequency of a wing of anisoptera(dragonfly) was calculated by using finite element method and experimental frequency response function. Flapping motion of zygoptera(dragonfly) was considered in resonant frequency of the designed wing structure. The experimental results show that the IPMC wing structure of dragonfly has a good flapping performance in resonant frequency.
Sputter-Deposited Nano-Metal Films in a Short Period for Electromagnetic Shielding Textiles
Authors: Du Wen Qin , Yu Fei , Qi Hong Jin
Published: November 2010

For continuous production of electromagnetic shielding fabrics, in short time, 3 min., copper, silver, tin and nickel were used to fabricate the coating by magnetron sputtering. By analysis and comparison of depositing rate, dB value and SEM images, the multi-layer displays an inhibition of the electromagnetic shielding effectiveness (ESE), which may resulted from the metal contact potential. It is found that the ESE of the multi-layer rely on the continuity of the bottom layer structure. The bridge-linking of the top layer particles seems lead to the slight increase in particle continuity in the lower layer and hence the ESE of the multi-layer increases somewhat compared to the single silver layer obtained for less time. After the screening experiment, silver has been chosen to fabricate single coating on the PET fabric. The fabric prepared by optimizing parameters has excellent ESE and potential application.
Preparation and Characterization of Poly(Lactic Acid)/Ethylene Glycidyl Methacrylate Copolymer Blends
Authors: Tsou Chi Hui , Li Ya Ming , Yao Wei Hua , Yeh Jen Taut
Published: November 2010

Both tensile and tear strength values of PLAxEGMCy blown-film specimens in machine and transverse directions improve significantly and reach the maximum values as their EGMC contents approach an optimum value of 6 wt%. The melt shear viscosity values of PLAxEGMCy resins measured at varying shear rates are significantly higher than those of the PLA resin and increase consistently with their EGMC contents. FT-IR analysis suggest that the carboxylic acid groups of PLA molecules react with the epoxy groups of EGMC molecules during the reactive-extrusion processes of PLAxEGMCy specimens. Further DMA and morphological analysis of PLAxEGMCy specimens reveal that EGMC molecules are phase-separated with PLA molecules at EGMC contents equal to or more than 2 wt%, since distinguished phase-separated EGMC droplets and tanδ transitions were found on fracture surfaces and tanδ curves of PLAxEGMCy specimens, respectively. Possible reasons accounting for the above interesting properties of the PLA/EGMC specimens are proposed in this study.
Investigation of Microstructure and Property of Fe3Al/Al2O3 Composites
Authors: Jiang Tao
Published: November 2010

The Fe3Al/Al2O3 composites were fabricated by pressureless sintering process. The Fe3Al intermetallics compounds powders were fabricated by mechanical alloying and heat treatment, then the Fe3Al powders and Al2O3 powders were mixed and the Fe3Al/Al2O3 composite powders were prepared, so the Fe3Al/Al2O3 composites were fabricated by sintering process at 1700oC for 2h. The phase composition and microstructure of Fe3Al intermetallics compounds powders produced by mechanical alloying and heat treatment were investigated. The phase composition, microstructure and mechanical properties of the Fe3Al/Al2O3 composites sintered bulks were investigated. The XRD patterns results showed that there existed Fe3Al phase and Al2O3 phase in the sintered composites. The Fe3Al/Al2O3 composites sintered bulks exhibited the homogenous and compact microstructure, the Fe3Al particles were homogenously distributed in the Al2O3 matrix, the mean particles size of Fe3Al intermetallics was about 3-5μm. The Fe3Al/Al2O3 composites exhibited more homogenous and compact microstructure with the increase of Fe3Al content in the Al2O3 matrix. The density and relative density of the Fe3Al/Al2O3 composites increased gradually with the increase of Fe3Al content. The fracture strength and fracture toughness of the Fe3Al/Al2O3 composites increased gradually with the increase of Fe3Al content. The elastic modulus and hardness (HRA) of the Fe3Al/Al2O3 composites decreased gradually with the increase of Fe3Al content.
Microstructure and Properties of Fe-Based Laser Cladding Coatings Reinforced by In Situ Synthesized Multiphase Ceramic Particles
Authors: Li Gui Hua , Zou Yong , Zou Zeng Da , Dong Xu Wei
Published: November 2010

The Fe-based composite coating reinforced by in situ synthesized multiphase ceramic particles has been successfully prepared by laser cladding preplaced powder on 42CrMo steel. The experimental results of X-ray diffraction and scanning electron micrograph indicate the coating is consisted by γ-Fe phase and Fe-Cr fine phase which possesses the better oxidation resistance and corrosion resistance. In-situ synthesized V(C,N), Cr2B3 and Cr3C2 particulates which are uniformly distributed in the composite coatings. The wear test showed that these reinforcement particulates improved significantly wear resistance of the coatings. The wear mass loss of the coating is about one tenth of the 42CrMo substrate. Laser cladding layers have better oxidation resistance. The oxide scale of the coatings is one eighth of the substrate through 750 constant temperature for 120h oxidation.
Effects of Different Pretreatments of Wood Fiber on Mechanical Properties of Biodegradable Composite
Authors: Wu Yi Qiang , Qin Zhi Yong , Qing Yan , Li Xin Gong
Published: November 2010

Biodegradable composites of polylactic acid reinforced with wood fiber were fabricated by using twin screw extruder followed by the injection molding machine. The effects of different pretreatments of wood on mechanical properties of the biodegradable composite were discussed. The nature of composites were also examined through scanning electron microscope and Infrared Spectrum Analysis, the results reveal that both acid and stearic acid could be used as effective surface modifier for wood fiber/polylactic acid system, the composite system by adding Benzoic acid, the tensile strength has improved greatly, and about stearic acid composite system, the impact strength has improved significantly; After alkali treatment, coupling agent treatment and combination of alkali treatment and coupling agent treatment, and the use of alkali treatment and the coupling agent treatment is the best, follow by alkali treatment.
A Simple Experimental Method to Simulate the Fracture and Faults in Earthquakes
Authors: Kida Katsuyuki
Published: November 2010

In the present work we present the results of a simple laboratory experiment which fulfils the mechanical conditions of formation of fracture and faults in earthquakes and also helps us understand the relation between inter- and intraplate earthquakes. Although many experimental investigations have been undertaken in an attempt to understand this relationship, they were not successful due to the difficulty in duplicating the conditions causing earthquakes using experimental methods. We discovered that the stress field around a subsurface crack growing under rolling contact fatigue fulfils the mechanical conditions of a plate subduction boundary, and also that subsurface crack branching is similar to the fracture of earthquake faults.
Coated Hydrophilic Thin Film on Glasses Using Freeze Drying-Assisted Sol-Gel Technique for Self-Cleaning Building Materials
Authors: Lin Tao , Zhang Xiang Chao
Published: November 2010

Titanium dioxide thin film has been successfully synthesized deposited on ITO glass substrates by the sol–gel dip-coating method using freeze drying technique. The precursor and TiO2 film were characterized using XRD, AFM and UV-vis absorption spectra analysis technologies. The XRD result demonstrates that the TiO2 film is well crystallized and consists of anatase phase only with (101) plane. The morphology of the nanoparticles of TiO2 thin film is spherical shape with grain size of 30.1 nm in average diameter and the surface of the TiO2 film is smooth. There is a strong wide UV absorption band around 387 nm and the calculated band gap (Eg) value of the TiO2 thin film is about 3.18 eV. The water contact angles for the thin film was only about 12°. The freeze drying-assisted sol-gel technique offers a novel process route in treating hydrophilic glasses for self-cleaning building materials and would be widely application for building energy saving.
Fabrication and Mechanical Characterization of nmSiO2/EP Composites by Shock Wave Method
Authors: Lin Guang Yi , Qu Dian Wei , Fu Yong Xiang
Published: November 2010

A systematic study has been carried out to investigate matrix properties by introducing nmSiO2 fillers into an epoxy resin matrix. The study has revealed that with shock wave method, nanoparticle infusion brings about superior mechanical properties to the matrix than what is usually given by the other method. The nmSiO2 is dispersed in a high-energy liquid shock wave pressure processing. The resulting structural composites have been tested under tensile loads to evaluate mechanical properties. Shock wave mixing utilized high-energy, high voltage transient shock wave in the water medium to process the material lying in the focal area. Nanoparticles tend to reduce void content of the nanocomposites and thus translate into increased mechanical properties. Focused, the influence of the high-energy shock wave method on the mechanical properties of nanocomposite were systematic studied. Using different processing conditions, the experiments were done to find the best processing. Overall, shock wave method is shown as a promising methode for preparation of aerospace epoxy composites.
Factors Effect on Grain Refining of Nanocrystalline Copper Fabricated by Explosive Loading and its Dynamic Mechanical Property
Authors: Wang Jin Xiang , Zhou Nan , Zhao Zheng
Published: November 2010

By the method of severe plastic deformation at high strain rate of coarse-grained copper under explosively dynamic loading, nanocrystalline(NC) copper was fabricated. The deformation process were simulated recur to Ls-Dyna3d finite element program , the effects of the strain on the degree of grain-refining were analysed. Finally, the dynamic mechanical properties of the NC copper were researched recur to split Hopkinson pressure bar(SHPB). The results show that it is feasible to fabricate nanocrystalline copper by explosively dynamic plastic deformation of coarse-grained copper and the grain size of the NC copper can be controlled less than 100 nanometer; higher strain at high strain rate is beneficial to the grain refining; the distribution of the grain size is not uniform along the loading direction; dynamic yield strength of the NC copper enhences with the decreasing of the average grain size and increasing of the strain rate.
Study on Electrodeposition of Ni-Graphite Composite Coatings in Sulfamate Bath
Authors: He Xiang Zhu , Zhang Xiao Wei , Zhou Xin Li , Fu Zhi Hong
Published: November 2010

This paper presented the composite coatings of nickel with graphite particle on the aluminum substrate using a nickel sulfamate bath. Effects of graphite particle concentration on the surface morphologies of the composite coatings were investigated. The inclusion of graphite particle into metal deposits was dependent on many process parameters, including particle concentration, current density, pH and temperature. Results of SEM and XRD demonstrated that graphite particle had successfully deposited on that nickel matrix; besides, the surface morphology of coatings obtained from sulfamate bath containing 2g/L graphite particle dispersed more uniformly than the ones with higher concentration.
Energy Properties of Building Structures Subjected to Strong Earthquake
Authors: Zheng Jin , Chen Bo , Ye Chun Yang
Published: November 2010

The evaluation on energy characteristics of earthquake-excited building structures with seismic protection devices is actively carried out in this study. The mechanical model of passive friction dampers is first introduced and the dynamic model of building-damper system is proposed. The evaluation criteria of energy responses are developed and applied to the earthquake response mitigation of a real multi-story building incorporated with friction dampers. The observations indicate that the earthquake-induced vibration of the structure can be substantially suppressed and the proposed energy evaluation criteria can be effectively utilized in the examination on seismic mitigation performance.
Interface Study of Short Mullite Fiber Reinforced Al-Cu-Si Alloy Composites
Authors: Long Jian Ping , Li Wei , Chen Shan Hua , Lin Jin Hui , Zeng Ying
Published: November 2010

Short mullite fiber reinforced Al-Cu-Si alloy composites were produced by squeeze casting. The interfacial microstructure and microchemistry of the testing composites were studied by means of X-ray diffraction (XRD), transmission electron microscope (TEM) and energy disperse spectrum (EDS) equipped with TEM, respectively. It is shown that chopped mullite fibers in the composites are polycrystalline in structure composed of many fine mullite crystal particles which are orthorhombic in structure with lattice constants of a = 0.749 nm, b = 0.927 nm and c = 0.581 nm based on electron diffraction (ED) analysis and high resolution transmission electron microscope (HRTEM). There are much denser dislocations in the near vicinity of both fiber/matrix interface and silicon/matrix interface. But interfacial reaction products at fiber/matrix interface in (3Al2O32SiO2)/Al-4.0Cu-5.0Si composites have not been observed yet.
Structural Transformation of Aluminum Nanowires during Solidification
Authors: Zhou Guo Rong , Guo Zhong Quan , Teng Xin Ying
Published: November 2010

The computer simulation of the structural evolutions of Al nanowires on cooling has been carried out based on the embedded atom method potential. The infinite Al nanowire was modeled by super-cell with a one-dimensionally periodical boundary condition along the [001] direction. The simulation results indicate that the microstructure of Al nanowires changed from amorphous to helical multi-shelled structure along with the drops of cooling rate. The helical multi-shelled structure possesses some features of amorphous structure, but it is more stable than the later. Moreover, the Al nanowires still keep the helical multi-shelled structure even if the cooling rate decreased to 1010 K/s.
Design Method for Braiding Process and Structure Parameters of Three Dimensional Two-Step Tubular Braided Preform
Authors: Gao Yan , Li Jia Lu
Published: November 2010

The properties of composites reinforced by three dimensional braided preform are determined by braiding structure significantly. The main objective of this paper is to develop a general methodology for the determination of the design and analysis of three dimensional two-step braided tubular preform. The arrangement pattern of axial yarns with various finenesses is derived for the uniform braiding structure of preform, which offers a possibility for achieving preferable interior structures of braided tubular preforms. Then, the general structure parameters, including the interrelation between surface braiding angles and interior braiding angles and the fiber volume fraction, are investigated in some detail. The results derived from this paper can provide a useful method for the design of 3D two-step tubular braided preform.
Deposition of ZnO:Al Thin Films by Ultrasonic Spray Pyrolysis
Authors: Dong Lin , Pei Teng Fei , Li Hong Qing , Xu Da Yan
Published: November 2010

Transparent conducting Al-doped ZnO films were prepared by ultrasonic spray pyrolysis technique on amorphous glass substrates under atmospheric environment with substrate temperature ranging from 350 to 500 , and Al/ZnO molar ratio of 1, 3 and 5 %. The impacts of the substrate temperature and doping level on structural, optical and electrical properties of the ZnO:Al thin films were investigated. The texture coefficient calculated from XRD data indicates that the substrate temperature at 450 and the doping level of 3 at.% is beneficial for crystal growth along (002) orientation. The Band gap (Eg) and Urbach parameter (E0) deduced by the optical absorption edge increases and decreases with the increase of Al doping level, respectively. The increase in sheet resistance is assumed to be associated with the decrease in preferential orientation and formation of Al2O3-x clusters.
Study on Material Selection and Manufacturing Process of Wind Turbine Blades
Authors: Xu Jin , Zhang Wei , Wang Chun Xia
Published: November 2010

The materials and structural characteristics of several kinds of wind turbine blades are introduced and analyzed as well as the advantages and disadvantages of blades composites in this paper. Then the manufacturing technologies between traditional and high-quality composite wind turbine blades are studied and compared in this paper.
In Situ Fabrication and Properties of Mg2Si/AZ91D Magnesium Matrix Composites
Authors: Wang Xiao Ying , Zhao Yu Tao , Chen Gang , Zhang Song Li , Cheng Xiao Nong
Published: November 2010

Mg2Si/AZ91D magnesium matrix composites are fabricated from AZ91D-Al2(SiO3)3 system by direct melt reaction method. The effects of the variation Al2(SiO3)3 addition contents to the microstructures and mechanical properties of the composites are investigated. The results show that the amounts of Mg2Si particles are increased and the structures of AZ91D magnesium alloy are refined with the Al2(SiO3)3 content increasing. When the additional content of Al2(SiO3)3 is 3wt.%, the tensile strength of the composite reaches 178.6MPa, which is increased by nearly 14.5% than that of AZ91D matrix alloy.
Applications of Biorthogonal Non-Tensor Trivariate Wavelet Traits in Construction Engineering Management
Authors: Lv Yan Hui , Yu Yu Min
Published: November 2010

Wavelet analysis is a popular subject in science research. The notion of univariate orthog- -onal wavelet packs is generalized. First, the notion of biorthogonal nonseparable trivariate wavelet packs is proposed and a procedure for constructing them is presented. Next, the biorthogonality pro- -perty of trivariate wavelet packs is investigated, and three biorthogonality formulas of wavelet packs are established. Moreover, it is shown how to gain new Riesz bases of space from these wavelet packs.
Surface Intergrity of Inconel 718 under MQL Condition
Authors: Che Haron Che Hassan , Ghani Jaharah Abd , Kasim Mohd Shahir , Soon T.K. , Ibrahim Gusri Akhyar , Sulaiman Mohd Amri
Published: November 2010

The purpose of this study is to investigate the effect of turning parameters on the surface integrity of Inconel 718. The turning parameters studied were cutting speed of 90, 120, 150 m/min, feed rate of 0.15, 0.25, 0.25mm/rev and depth of cut of 0.3, 0.4, 0.5 mm under minimum quantity lubricant (MQL) using coated carbide tool. surface response methodology (RSM) design of experiment using Box-Behnken approach has been employed consisting of various combination of turning parameters Surface roughness, surface topography, microstructure and the micro hardness of the machined surface were studied after the machining process. Feed rate was found to be the most significant parameter affecting the surface roughness. The optimum parameter was obtained with Ra equal to 0.243 µm at cutting speed of 150 m/min, feed rate of 0.25 mm/rev and depth of cut of 0.3mm. A mathematical model for surface roughness was developed using Response Surface Methodology. The effect of turning parameters and factor interactions on surface roughness is presented in 3D graphical form, which helps in selecting the optimum process parameters to achieve the desired surface quality.
Open-Air Storage Time Impact on Performance of PSP Used as Concrete Admixture
Authors: Lin Yu Qiang , Shi Yan , Li Jia Zheng , Yang Hua Quan
Published: November 2010

Paper studies on phosphorus slag powder(PSP) processed from phosphorus slag with different open-air storage time, analyses the changes in the performance of PSP and the impact on properties of cementitious materials. The results showed that with the growth of open storage time, vitreous structure of PSP would gradually be decomposed, part of the vitreous would transform into crystal form. Density of powder would diminish and ignition loss increase. Activity of PSP would slowly decreases, and the activity differences main reflected after 90d. Concerning on the point of concrete strength rating, 10 years phosphorus slag can still be used. The above provide a basis for resource utilization of phosphorus slag with long storage time.
Preparation and Mechanical Properties of Polyurethane Elastomer with Two Soft Segments of HTPB/PTMG
Authors: Tao Hai Tao , Liu Xi Jun , Ma Tie Ning
Published: November 2010

In this paper, a series of polyurethane elastomers (PUE) were prepared employing casting method using toluene diisocyanate (TDI), hydroxy-terminated butadiene-acrylonitrile copolymer(HTBN) and polytetrahydrofuran glycol (PTMG) as the main raw materials, and using 2,4- and 2,6- dimethylthioaromatic diamine (DMTDA) as a chain extender. The effects of the content of NCO in PUE (NCO%), mass ratio of HTBN/PTMG, molecular weight of PTMG, dosage of chain extender and heat treatment on the mechanical properties of PUE were studied. The results showed that the lower molecular weight of PTMG and the higher heat treatment temperature were both favorable for increasing the mechanical properties of PUE. When the mass ratio of HTBN/PTMG was 35:65, NCO% was 6.0%, molar ratio of NCO/NH2 was 1.20 and heat treatment time was 2h at 115 , the mechanical properties of PUE were best.
Application of the Calculator Technique in the Ability about the MMCs of the Anti-Vibration
Authors: Gao Hui Ting , Meng Song He , Cao Zhan Yi , Xu Li Na
Published: November 2010

According to the dissipation energy principles of plastic Three-dimensional finite element analysis of antiseismic capability of Fe/Zn composite by the finite element software ANSYS. It is the very first time to study responds process of earthquake of metal layer composite. Observed in “Time Hist Postpro” that biggest stress of Fe is lower than the yield intensity of Fe, the biggest stress of Zn is bigger than the yield intensity, Fe supports load and Zn absorbs energy are proved. It is provided to the theories for the system of the new material according to.