bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Fe3+/Ag+ Co-Doped Nanometer TiO2 Photocatalyst with Sol - Gel Auto-Igniting Method
Authors: Shi Zai Feng , Guo Shu
Published: December 2011

To study the preparation of Fe3+/Ag+ co-doped TiO2 photocatalyst with sol-gel auto-igniting method, TiO2 powder was prepared with TiCl4 as raw material and the photocatalytic activity of doped TiO2 was examined with methylene blue (MB) as water samples, and a 15w low pressure mercury lamp as light source. Results showed that: the TiO2 co-doped with 0.02% (molar ratio) of Fe3+ and 0.5% (molar ratio) of Ag+ gives the highest photocatalytic activity. The according photodegradation rate constant of MB is 1.33 and 1.10 times of that with TiO2 and Fe/TiO2 separately.
Effects of Hair Fibers on Braking Friction Materials
Authors: Ma Yun Hai , Wang Bao Gang , Shen Sheng Long , Geng Xue Ying , Jia Hong Lei , Wen Shuang
Published: December 2011

In this experiment, the effects of hair fibers on friction and wear property, Rockwell hardness and impact strength of friction materials were examined. The results showed that friction coefficient increases and stabilizes and specific wear rates were decrease as the hair fibers were filled and, particularly, 1% of the hair fiber content had a significant effect in the friction material. As temperature was changed, the stability of the friction coefficient of friction materials can be improved, the Rockwell hardness decrease and the impact strengths increase by way of increasing the content of hair fibers. The worn surfaces of friction materials were examined by scanning electron microscopy and wear mechanisms were analyzed. So it’s a kind of quite good non-asbestos friction material.
Simulation and Experimental of Magnetron Sputtering Film Thickness Distribution
Authors: Wang Jin Xin , Han Ya Ping , Gao Xue Lian , Luo Ming Hai , Wang Shao Ze
Published: December 2011

A physical model of magnetron sputtering process was built, the distribution of film thickness on the substrate was deduced, and the data were analysised by using the Mathematica and Matlab. The results show that the distribution of the film thickness on the substrate is uneven and it is also influenced by the radius as well as the distance between the target and substrate. The results of experiment correspond fairly well with the theory. The relational expression provides a theoretical basis for evaluation and estimation of the film thickness.
Study of Solidification Microstructures of Multi-Principal High-Entropy Alloy FeCoNiCrMn by Using Experiments and Simulation
Authors: Ye Guo Xin , Wu Bo , Zhang Chao Hui , Chen Tuo , Lin Mao Hua , Xie Yong Jiang , Xiao Ya Xiang , Zhang Wen Jun , Zhang Li Kun , Zheng Zhen Huan , Wang Chen
Published: December 2011

The microstructures and the solidification processes simulation of multi-principal high-entropy alloy FeCoNiCrMn were studied by using both experimental and computational approaches. The microstructures were identified by methods of XRD, SEM and EDS. The solidification process was simulated by Scheil-Gulliver solidification model. The alloy mainly forms a single FCC solid solution, but Mn atoms, as well as Ni atoms tend to be enriched in residual liquid phase during the solidification process. These atoms show interdendritic segregation. Present experimental results and computational results are supported each other well.
Analysis on Tensile Properties of Stainless-Steel Fiber and Yarn Quality
Authors: Sun Yu Chai , Cheng Zhong Hao , Zhang Yan Mei
Published: December 2011

Stainless steel fiber is a new sort of soft industrial material developed in the past decades. The pure stainless fiber has a number of outstanding properties and is getting wider range of application in textiles which are used as industrial textiles. The tensile properties between stainless steel fiber and traditional textile fibers are quiet different. The property differences between stainless fiber and common textile fiber made the textile processing of stainless fiber difficult. Based on the testing of breaking force, breaking strength and breaking elongation rate, this paper analyzed the tensile characteristic of stainless fiber and discussed its effect on yarn quality.
The Twinning Modes of B2-B19′ Martensitic Transformation in NiTi Alloys - A Phase Field Study
Authors: Ke Chang Bo , Cao Shan Shan , Ma Xiao , Zhang Xin Ping
Published: December 2011

A three-dimensional phase field model applicable for the B2-B19′ martensitic phase transformation of NiTi alloys was developed to predict the twinning modes in the B2-B19′ transition. The phase field simulation results showed that by taking into account the transformation induced elastic strain, the martensite variants were self-accommodated and sheared along the specific interface in the entire transition stage for reducing the elastic energy, whether the formed interface between the variants belongs to twinning plane could be determined by calculating the minimum value of long range elastic interaction energy, Bpq. Through comparison with the existing analytical solutions, it is demonstrated that the phase field model can be used to predict the type I twinning modes in the B2-B19′ phase transition with good precision.
Thermodynamics Analysis in the Simulation Process of γFe → αFe Isothermal Transformation’s Grain Nucleation and Growth
Authors: Zhang Gen Yuan , Lv Dan Xia , Zhao Guan Xing , Zuo Fei
Published: December 2011

Physical simulation model of γFe → αFe grain nucleation & growth in isothermal solid-state transformation and the rule of grain nucleation & grain growth’s boundary migration are established. The Genetic Algorithm is introduced in the process of grain nucleation & growth. The grain boundary migration agrees with the theory of grain growth. The system free energy ΔG calculation formula is exported. The thermodynamic criterion of new nucleus growing up is that new grain average radius rc is bigger than theory critical average radius rc0 when ΔG is achieved ΔGmax, ΔG is continually decreased at the remaining transformation, the final energy ΔGf is less than initial energy at the end of transformation; be influenced by the limit of nucleation number N.
The Realization of Numerical Control Machining of 2D Parts Based on MasterCam FBM
Authors: Yun Zhi Dong , Dai Ming He
Published: December 2011

Apply the function of FBM Mill and FBM Drill built in MasterCam to achieve the automatic NC programming and machining of solid parts.The feature modeling of parts is produced in Solidworks, and then converted to MasterCam. After the stock size of parts and FBM parameters are set, the features of parts are recognized automatically; and all of the 2D toolpaths of parts are automatically generated in a specified machine. Finally, the automatically generated NC toolpaths based on features are verified by simulating. FBM technology is adopted to eliminate the manual processes involved in identifying features for programming milling and drilling operations on solid parts, thus greatly increasing the efficiency and flexibility of programming, which is an effective method of achieving automatic NC programming.
650°C Long-Term Structure Stability Study on 18Cr10NiNb Heat-Resistant Steel
Authors: Yu Hong Yao , Chi Cheng Yu , Dong Jian Xin , Xie Xi Shan
Published: December 2011

The Nb-contained austenitic heat-resistant steel 18Cr10NiNb(TP347H) has been widely used as super-heater and re-heater tube material for modern ultra-super-critical (USC) power plants in the world. High temperature structure stability is considered to be one of the most important factors for long-term service. Long-term aging at 650 °C for this steel was conducted till 10,000 hours. Effect of aging time on microstructure was studied by means of SEM and TEM. Tensile tests were carried out after aging at 650 °C for different times. Experimental results show that MX phase and M23C6 carbides are major strengthening precipitates in this steel. With increasing of aging time, fine nano-size MX particles precipitate in grains and its size keeps about 50 nm till 10,000 h at 650 °C. Carbide M23C6 mainly precipitates at grain boundaries but coarsens quickly. Investigation results show that MX phase plays the most important strengthening effect in grains. The amount of MX phase increases with increasing of Nb and C contents. The effects of Nb and C contents on mole fractions of MX phase in 18Cr10NiNb steel have been calculated by using Thermo-Calc software.
Research Materials of Chills Effect on the Solidification Process of ZM5 Shell
Authors: Zhao Si Cong , Guo Er Jun , Wang Li Ping
Published: December 2011

A commercial software, MAGMASOFT, was used to simulate the ZM5 shell with different materials of chills. The calculated results of solidification are obtained. Shrinkage porosity is predicted by means of a built-in porosity criterion. It shows that using the different materials of chills, such as copper, gray iron and steel, a large amount of shrinkage porosity defects are formed in ZM5 shell. However, with graphite as the material of chills, shrinkage porosity defects of ZM5 shell can be effectively reduced.
Study on Infiltration Kinetics of High Temperature Self-Lubrication Composite by Pressure Infiltration
Authors: Wang Bin , Wang Yan Jun
Published: December 2011

In this paper, the kinetics of infiltration of 60Sn40Pb-10Ag molten solid lubricants into the TiC-Fe-Cr-W-Mo-V ordered porous sintering body were studied and the effective infiltration model which was used to analysis the kinetics of infiltration was established. The infiltration process was simulated by finite element method. The result showed that the main influence factors on the infiltration quality were the pressure ,the temperature and the time.
Effect of H2S/CO2 Pressure on the Corrosion Behaviors of L360QCS in the Environments Containing Elemental Sulfur
Authors: Zheng Shu Qi , Chen Chang Feng , Chen Li Qiang , Li Chun Yu
Published: December 2011

The weight-loss method was used to study the effect of H2S/CO2 pressure on the corrosion behaviors of L360QCS in the environments with the existence of elemental sulfur and H2S/CO2. The morphologies, compositions and structure of corrosion products formed at different partial pressures were studied by the means of SEM, EDS and XRD techniques. The results show that the existing of H2S/CO2 increases the corrosion rate sharply and the corrosion rate increase dependence on H2S/CO2 pressure. At low gas pressure the production is mainly cubic FeS crystal while that is square FeS crystal at high pressure.
Numerical Simulation of the Tunnel Oven with Fluent Software
Authors: Wan Ming Wei , Zhang Suo Huai
Published: December 2011

After the model of sterilization area was established, numerical simulate was completed with fluent software. Verified with certain conditions of hot air velocity, the laminar flow tunnel oven is able to meet the relevant requirements of GMP. Under different speeds of hot air, the tunnel oven vials’ relationship between temperature and time, combined with analysis of pressure distribution inside the oven. When the air speed range from 0.6m/s to 1.5m/s, the temperature of vials meet the requirements and the minimum effect of negative pressure to oven.
Study on Hot Processing Maps and Flow Instability of 1235 Al Alloy Treated by Different Methods of Purification
Authors: Fu Gao Sheng , Yan Wen Duan , Chen Hong Ling , Chen Gui Qing , Cheng Chao Zeng
Published: December 2011

Based on the theory of processing map proposed by PRASAD, the power dissipation maps, the hot deformation instability maps and the hot processing maps of 1235 Al alloys treated by different methods of purification were built, and the effects of purification and deformation conditions at elevated-temperature on hot workability of 1235 Al alloy were analyzed. At the same time the optimum processing region and flow instability region were determined. The results show that the hot processing map of 1235 Al alloy has two instability zones in the temperature range of 300-500°C and in the strain rate ranging from 0.01s-1to 10.0s-1up to a true strain of 0.7, that is, one zone lying in the range of lower temperature and higher strain rate, the other zone in the range of higher temperature and mid strain rate. The purification effect has significant impact on hot workability of the alloy. It is found that the optimum processing region of 1235 Al alloy treated by high-efficient purification treatment is present in the range of higher temperature and lower strain rate zone, and its power dissipation efficiency is about 46%; while the optimum processing region of 1235 Al alloys treated by conventional refining treatment is present in the range of mid-temperature and lower strain rate zone or in the range of higher temperature and strain rate zone, and its power dissipation efficiency is about 23-29%. The results of observation of the deformation microstructure of 1235 Al alloy are in accordance with that of the hot processing maps of the alloy, thus showing that the calculation results of the hot processing maps are reliable.
Performance Evaluation of SHY-99 Coating for Carbon Steel Water-Cooler
Authors: Chen Bing , Li Xiao , Fan Yu Guang
Published: December 2011

Special SHY-99 anti-corrosion coatings are used for newly developed heat exchange equipment, to resist corrosion and leakage problem of carbon steel water-cooler. The anti-corrosion properties of coatings were examined with routine test methods, Scanning Electron Microscope (SEM), electro kinetic potential polarization curve method and immersion testing method. The results show that physical properties of coatings are in accordance with national standards, the microstructures of coatings are uniform and tight, the coatings are combined tightly with base metal, and the coatings show excellent corrosion resistance in water of water cooling system.
Preparation and Characterization of Paclitaxel Imprinted Silica Nanoparticles
Authors: Li Jian Hua , Zheng Zong Jian , Fu Shao Ping , Zhu Jing Bo
Published: December 2011

Highly selective molecularly imprinted layer-coated silica nanoparticles for paclitaxel were synthesized by molecular imprinting technique with a sol–gel process on the supporter of silica nanoparticles. The morphology of the obtained polymers was characterized by scanning electron microscopy (SEM). The binding properties of the imprinted polymers were evaluated through the equilibrium rebinding experiments. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymers with equilibrium dissociation constants of 0.0509 g•L-1and 0.0094 g•L-1, respectively. Paclitaxel and its analogue were employed for selectivity tests. The results indicated that the imprinted polymers exhibited good selectivity and specificity toward paclitaxel.
Effect of Negative Bias Voltage on Corrosion Resistance of TiN Coating Deposited by MAIP
Authors: Yuan Lin , Gao Yuan , Zhang Wei , Wang Cheng Lei , Ma Zhi Kang , Cai Hang Wei
Published: December 2011

In this study, TiN coatings were deposited on 201 stainless steel by multi-arc ion plating (MAIP). The effect of negative bias voltage on the surface microstructure, hardness, phase structure and the corrosion resistance of the coatings were investigated by SEM, hardness instrument, XRD and electrochemical measurement. The number and size of droplets decreased when the negative bias voltage increased from -100 V to -300 V. But when the substrate bias increased to a certain value, there were some pits appeared. The hardness increased at first and decreased later with the increasing of the negative bias voltage. When the negative bias voltage was -200 V, the hardness was the highest. The intrinsic hardness of TiN film was 2195HV. In 3.5% NaCl solution, the corrosion resistance of TiN coatings samples were improved slightly compared with 201 stainless steel. In l mol/L H2SO4 solution, the corrosion resistance of -100V sample was the best, the corrosion resistance of -100V coating sample was increased 486 times compared with untreated 201 stainless steel.
Nb-C Alloyed Layer Prepared on TiAl Alloys by Plasma Treatments and its First-Principles Investigation
Authors: Liu Xiao Ping , Ce Pei Lin , Wang Zhen Xia , He Zhi Yong
Published: December 2011

A Nb-C alloyed layer formed on TiAl by plasma Nb alloying followed by carburization was investigated. The alloyed layer was characterized using SEM, TEM, XRD and GDS. Effects of Nb alloying and the carburizing atmosphere on microstructure of Nb-C alloyed layers were analyzed. The forming mechanism of the Nb-C alloyed layer was verified using first-principle calculation. The results reveal that the Nb-C alloyed layer is composed of NbC and Nb2C. An addition of niobium in TiAl accelerates the diffusion of carbon atoms in the Nb-alloyed layer, leading to a thicker alloyed layer with higher carbon content. The carbon concentration and diffusing depth increase with methane gas. First-principle calculation shows that the forming energy of Nb-C duplex-treated TiAl is lower than those of single carburized TiAl and Nb-alloyed TiAl.
Characteristics of Surface and Interface of Mercury-Stannum Reactive Wetting at Room Temperature
Authors: Liao Xuan Mao , Zhu Ding Yi
Published: December 2011

Mercury-stannum reactive wetting behaviors were studied by the sessile drop technique at room temperature, and wetting surface and interface were also studied respectively by methods of field emission scanning electron microscope (FESEM) and XRD. It showed that mercury droplets wetted completely on the stannum substrate, on whose surface up-and-down cellular structures were generated, and two metallographic microstructures of intermetallic compounds, Hg0.1Sn0.9 and Hg1.25Sn8.75, were produced in wetting interface.
Synthesis and Characterization of Lamellar Nanostructured Yttrium Films Using Lyotropic Liquid Crystalline Templates
Authors: Guo Rui Jie , Sha Xiao Juan , Cao Lei Lei
Published: December 2011

The lamellar nanostructured yttrium films on α-Al2O3 substrates were successfully synthesized by electroless deposition using the lyotropic liquid crystalline templating strategy. The reaction of hydrazine hydrate and Y3+ dissolved within the aqueous domains of the lyotropic liquid crystalline phase produced the nanostructured yttrium films. The low-angle X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM) indicated that the as-resulted films possessed lamellar regular array of nanochannels with periodicity of 6 nm. With well-defined nanochannels and higher surface areas, the nanostructured films may find applications in the field of electronic materials.
Low Cycle Fatigue Behavior of Spray Formed Superalloy Rings
Authors: Xu Wen Yong , Zhang Guo Qing , Li Zhou
Published: December 2011

Low cycle fatigue behavior of spray formed superalloy GH738 at 650°C has been investigated under fully reversed total strain-controlled mode. When strain amplitude (Δεt/2) is between 0.32% and 0.4%, cyclic stress response is stable under fully reversed constant total strain amplitude. The stabilized hysteresis loops narrowing sharply to a straight line indicates that the alloy exhibits typical elastic strain. The crack initiates single site from the surface. When strain amplitude is between 0.6% and 1.0%, cyclic hardening is observed until fracture. The tendency for hardening is found to increase with strain amplitude. The hyperesis loops expand gradually, which indicates that plastic deformation happens during cyclic deformation process. The crack initiates multi-sites from the surface. The cyclic strain-stress relationship of spray formed GH738 at 650°C can be illustrated by Δσ/2 =2017(Δεp/2)0.1489.The total strain-life function can expressed by Δεt/2=0.0071(2Nf)-0.0781+0.0647(2Nf) )-0.4914.
Effect of Phase Composition and Microstructure of Oxide Scale on the Corrosion Resistance of SS400 Hot Rolled Strip
Authors: Zhou Xian Liang , Zhu Min , Hua Xiao Zhen , Ye Zhi Guo , Cui Xia , Nie Lun
Published: December 2011

Different phase compositions and microstructures of oxide scales were formed on the surface of SS400 hot rolled alloys by employing various heat treatment processes. Cyclic wet-dry immersion corrosion test, electrochemical impedance spectroscopy were used to investigate the corrosion resistance of strips with scales fabricated by different heat treatment processes. The results reveal that difference in the corrosion resistance of the various scales is due to the difference in the grain size of Fe3O4phase. Furthermore, the difference in the corrosion resistance of different oxide phases, exhibited by various scales, also render the strips to give various corrosion behaviors. It is surmised that the strip with oxide scale, which consist of a small mount of the outer layer Fe2O3phase distributed continuously and a large quantity of the inner layer Fe3O4phase with the fine grain size, and possess nice compactness, continuity, integrity in the morphology structure, has the best corrosion resistance.
The Study about Environmentally-Friendly Passivation Technology Process and Performance on Brass Surface
Authors: Xu Hong Yin , Li Li
Published: December 2011

The paper through the synergy before mixed Phytic acid and Sodium molybdate, Sulfosalicylic acid, Organic silane, and add the active substances PEG, Optimize the Passivation liquid formula of Brass surface, Phytic acid is the main ingredient, study the affection of Phytic acid Passive film Corrosion resistance on the three main Passivation conditions: Passivation temperature, time and Passivation solution PH value. The results show that，Phytic acid passivation film process recipes as follows：Phytic acid (quality score 50%) 2~5ml/L, sodium molybdate 4~8g/L, organic material 10~30ml/L, sulfosalicylic acid 3~7g/L, polyethylene glycol 2~6g/L, deactivated temperature 30~35°C, pH value 5, deactivated time 60s. The test showed that，the phytic acid passive film can obviously enhance the anti-corrosive performance on the brass surface, its corrosion resistance proportion chromates passive film is fairly good.
Growth Characteristics of Pulse Electrodeposition Fe-Si Layer
Authors: Yang Hai Li , Wu Li , Tang Guo Zhang , Li Yun Gang , Zhang Yu Zhu
Published: December 2011

Fe-Si layer was prepared on silicon steel substrate from KCl-NaCl-NaF-SiO2 molten salts by pulse current at different time. The quantitative Si concentration depth profile, surface morphology and phase structure of the layer were studied by glow discharge optical emission spectroscopy, atomic force microscopy and X-ray diffraction. The layer growing process was analyzed from nucleation process, growth pattern and microstructure. It was observed that the Fe-Si alloy nucleated in the way of three dimensional conical shape and initially grew in the orientation of matrix, then gradually adjusted to the lowest energy state. With deposition time going on, the phase structure of the layer changed in the order of -Fe (Si) →α-Fe (Si) ＋Fe3Si →Fe3Si
Microstructure and Oxidation of 55%Al-Zn-Si Hot-Dip Coatings Deposited on Low Carbon Steel at High Temperature
Authors: Zhou Biao , Jin Feng , Luo Qun , Li Qian , Chou Kuo Chih
Published: December 2011

The high temperature oxidation and microstructure evolution of 55%Al-Zn-Si coated sheets were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD). After oxidation, the coatings consisted of three phases including ZnO, Fe2Al5, and FeAl from topcoat to the substrate. The different diffusion rate of Fe and Al result in forming voids at the interface of intermetallic layer and the substrate. A good agreement has been reached between the experimental data and the calculation from Chou diffusion model, which has a good predicted function. Moreover, the characteristic oxidation time and the apparent activation energy were obtained.
The Study of Acid Doped Polyaniline Anticorrosive Coatings
Authors: Xu Hong Yin , Li Li
Published: December 2011

This topic in the reaction temperature, reaction time for 5 °C for 7 hours, aniline and ammonium persulfate mole ratio of 1:1 conditions, main research on synthesis of concentration of reactant polyaniline performance, yield, the influence of electric conductivity. By ir, conductivity meter, scanning electron microscope (sem) analysis of samples, and the results show that when the yankees salicylic acid concentration sulfonylureas 0.15-0.25 mol/L, ammonium persulfate concentration 0.1-0.2 mol/L got when the production rate is higher, anticorrosive performance is good polyaniline coatings.
Coupled Magnetic Field Enhanced Arc Ion Plating: Process, Plasma and Deposited Film
Authors: Lang Wen Chang
Published: December 2011

Based on the interaction mechanism of the plasma and the magnetic field, this paper has proposed the deposition process of coupled magnetic field to enhance the arc ion plating. Meanwhile, it has also analyzed the distribution, the polarity and the configuration of coupled magnetic field combining with the finite element simulation. The influence of coupled magnetic field on the distribution, the ionization rate, the surface quality of film and the deposition rate of arc ion plating has been also systematically discussed in this paper. What’s more, the reduction mechanism of coupled magnetic field for the marco-particles on film surface has been also proposed. The studies have shown that the DC coupled magnetic field can not only improve the focusing properties and the transmission uniformity of plasma, but also enhance the collision between ions and improve the ionization rate of plasma and the excitation illumination intensity of ions as well as improve the ion density. With the increase of the strength of DC coupled magnetic field, the number and the size of marco-particles on film surface have been greatly reduced and the deposition rate of film has been exponentially increased. The plasma has been gradually focalized and diverged under the influence of pulsation coupled magnetic field and formed the plasma with a dynamic distribution, which has enhanced the interaction between the plasma and the marco-particles as well as further purified the marco-particles.
Progress in Ice-Phobic Coating
Authors: Zhang Shu Ting , Wang Hui , Wang Lei
Published: December 2011

This paper summarizes the test method of ice-phobic coating adhesion strength and the progress in coating material. Ice adhesion strength of several commercial ice-phobic coatings were tested for Pratt & Whitney, and result indicated that reformative silicone R-2180 show significantly improved reduction in ice adhesion when compared to several different commercially available silicone-based ice-phobic coatings. It would be valuable in future studies to measure the surface energies of the several materials tested to determine any correlation between the ice adhesion and surface energy of the coating.
Electroless Deposition of Nickel on the Surface of Silicon Carbide Crucible from Alkaline Bath
Authors: Xiao Fa Xin , Shen Xiao Ni , Xie Jing Pei , Yang Di Xin , Ren Feng Zhang , Wang Ai Qin
Published: December 2011

This work aims to eliminate contamination of the surface of crucible with silicon carbide during fusion preparation sample of the X-ray fluorescence analysis used in relation to electroless Ni–P plating process on the surface of SiC crucible in the alkaline bath. The structure, morphology and component of the coated layers were clarified by means of XRD, SEM and EDAX. Also, the electrochemical measurements was carried out to characterize the reduction mechanism of Ni deposition. The bath compositions were nickel sulfate 20 g/L, sodium hypophosphite 30 g/L, sodium citrate 10 g/L，ammonium chloride 20 g/L, containing a mixed additives of thiourea, sodium lauryl sulfate and coumarin. The thickness of coating was 3.47 μm after plating for 15 min from this bath at 318 K. The coating is relatively dense and smooth and has a nodular surface morphology. The uniform Ni–P film is a mixture of microcrystalline of Ni5P4 and crystalline phases of Ni in the alkaline bath, with the components of 4.74%P and 95.26%Ni. The nickel deposition reaction occurs at -1.07 V appropriately with the peak current density of 32 mA/cm2 and the electrochemical deposition of nickel is mainly controlled by the electrochemical process.
Electrochemical Studies on the Passivation Behavior of Cu-Ni-Fe Alloy in Borate Buffer Solution at pH 8.4
Authors: Zhou Qiong Yu , Wang Yi , Zhong Qing Dong
Published: December 2011

Cu-Ni-Fe alloy-layer was prepared by the method of copper oxide- nickel oxide mixed powder deposited on the surface of mild steel samples and then treated under high temperature and hydrogen gas atmosphere. Polarization techniques and Mott-Schottky analysis in conjunction with the point defect model (PDM) have been used to investigate the semiconductor properties of the passive films formed on the surface of Cu-Ni-Fe alloy layer in borate buffer solution at pH 8.4. The results showed that the passive film formed on the surface was more compact, highly protective with higher heating temperature. Carriers density and vacancies diffusion coefficient of the passive film formed on Cu-Ni-Fe alloys decreased with higher heating temperature. The vacancies diffusivity is about magnitude of 10-20m2•s-1 in borate buffer solution at pH 8.4.
Post-Weld Oxidation Behavior of AA6061 Al Alloy
Authors: Che Lah Nur Azida , Jalar Azman , Othman Norinsan Kamil
Published: December 2011

Welded AA6061 Al alloy using ER5356 (Al-5Mg) filler was oxidized in flowing air gas for 40hrs at 600oC at a total pressure of approximately 1 atm. The morphology and microstructure of welded joint after exposure was characterized by using optical metallurgy microscopy and Scanning Electron Microscope (SEM). Different oxide morphologies and textures were observed on parent and fusion metal due to the differences of the alloying element. The oxidation mechanism represented a complex reaction occur where the morphology and phase formation of the oxide shows the protective oxide scales showed the protective oxide were developed on parent metal side, meanwhile non-protective oxide scale formed on fusion metal of the welded Al alloy. It can be concluded that the welded area failed to resist oxidation behavior compared to the parent metal. The differ results are discuss in term of microstructure changes caused by high temperature oxidation exposure and alloying element.
Model Tests Study on the Bending Properties of the External Pre-Stressed Combination Box Girders with Corrugated Steel Webs
Authors: Hu Juan , Sun Xiao Yi
Published: December 2011

In order to study actual work performance of the external pre-stressed combination box girder with corrugated steel webs, and to analyse the integral stress of box girder influenced by the corrugated steel webs, and understand the construction of the type combination box girder, this document studied the model test of the external pre-stressed combination box girder with corrugated steel webs, tried to find out the bending rule for the combination box girder and the model test result influenced by the different connections style. And the model test result was based on the assumption of “flat section” and within the elastic range, when the concentrated loads loaded on the box girder, the deflection was linear with the loads, and the corrugated slab stress was zero, which indicated the slab can not bended and the moment was supported by the top and the bottom slab, and the corrugated slab only supported the shear, and the shear lag effect only influenced local area. The conclusion of the model test will provide the reference for the bending capacity research, design and construction.
Study on the Thermal Degradation Kinetics of Modified Chloroprene Rubber Adhesive Dedicated to Bonding UHMWPE and 45# Steel
Authors: Hu Ping , Luo Qin Qin , Pan Meng
Published: December 2011

Modified neoprene adhesive dedicated to bonding UHMWPE and 45# steel was prepared. Thermal analysis with TG-DTG curve was determined and its thermal decomposition kinetics was studied. The result show that the thermal degradation process of CR/MMA/CPE/MgO adhesive is a three-step reaction and the its thermal degradation starting temperature is 200°C and complete decomposition temperature is 570°C. The first mass loss stage is 0.6 order chemical reaction and its average activation energy E is 19.21kJ/mol and pre-exponential factor A is 3.68×102. The second mass loss stage is 3 order chemical reaction and its average activation energy E is 82.14kJ/mol and its pre-exponential factor A is 1.52×108. The third mass loss stage is 3 order chemical reaction and its average activation energy E is 55.07kJ/mol and pre-exponential factor A is 1.33×105.
Influence of Inclusion on Fatigue Performance Evaluation of High Strength Transmission Shaft Steel
Authors: Xue Huan , Kuang Lan Xiang , Li Rong Feng , Ge Rui
Published: December 2011

Along with the improvement of surface defect and decarburizing problem, the non-metallic inclusion becomes one of the most important factors which influence the fatigue performance evaluation of metallic material. To quantitatively study this problem, two group of high strength transmission shaft steel with different inclusion level are selected to do the comparison fatigue test using stair case method. Experimental data shows that the inclusion of the metallic material will observably affect its fatigue performance. The comparative large size of Al2O3 inclusions with tip edge angle was found by stereo-scan and energy spectrum analysis, which were the sources of micro crack and lead the final fracture.
Effects of Low-Voltage Pulsed Magnetic Field and Pouring Temperature on Solidified Structure of Al-4.5%Cu Alloy
Authors: Zhou Quan , Chen Le Ping , Yin Jian
Published: December 2011

The solidified structure refinement of Al-4.5%Cu under the action of low-voltage pulsed magnetic field (LVPMF) was investigated in the paper. The influences of different pulse voltage and pouring temperature on solidified structure of Al-4.5%Cu alloy were studied. The results show that solidified structure of Al-4.5%Cu alloy can be refined greatly by LVPMF processing. The dendrite growth is restrained and the microstructure is changed from larger dendrite grains to smaller nondendritic grains, and with certain parameters, the equiaxed, non-dendritic grains are gained in the alloy. With the increase of pulse voltage, grain size of the alloy decreases, and the primary phase degrades from developed dendrites into rose-like or spherical crystals. The decrease of pouring temperature enhances the refinement effect of LVPMF processing. With 150 V pulse magnetic field treatment, grain size of the alloy decreases, primary phase degrades and refines gradually with the decrease of pouring temperature.
Mechanical Properties of Carbon Cathodes during Aluminium Electrolysis
Authors: Liu Qing Sheng , Fang Hui
Published: December 2011

Based on the service ambient with aluminium electrolysis condition, the evolution of compressive strength, elastic modulus and stress-strain curve of carbon cathode samples under various conditions are investigated by experimental simulation method; the deterioration mechanism of the mechanical of carbon cathode is also studied. Results show that different carbon cathode materials and ambient conditions have great influence on strength and elastic modulus of carbon cthode. The mechanical properties such as compressive strength and elastic modulus of carbon catodes can be degraded by the erosion of sodium and molten salt during aluminium electrolysis, that has been confirmation by the SEM and XRD analysis.
Inclusion Removal at the Free Surface of Steel Bath by Bubble Flotation
Authors: Jiang Fang , Cheng Guo Guang
Published: December 2011

In the present work, physical model experiments were carried out to clarify the inclusion removal at the free surface of steel bath. Polyethylene particles were used to simulate the non-wetting inclusions like alumina and silica. The influence of gas flow rate and bubble size on the inclusion removal at the free surface was evaluated. It is demonstrated that not all particles are removed when they arrive at the free surface of liquid bath, and those which are not removed will get back to the bath. It is found an annular particle layer is formed by the removed particles at free surface, which can capture other particles arriving at the free surface. However, the attachment of particles to the annular particle layer is not stable, and re-entrainment of particles occurs at high gas flow rate. It is shown the overall particle removal is determined by a balance of removal and re-entrainment. The particle removal constant increases with the increase in the gas flow rate, but decreases with the increase in bubble size. The equilibrium concentration of particles increases with the increase in gas flow rate and bubble size.
Prediction of the Tertiary Structure of α-Glycosidase from Aspergillus niger by Homology Modeling
Authors: Wang Fa Xiang , Wang Qin Yun , Liu Yong Le , Yu Jian
Published: December 2011

α-Glucosidases play critical role both in primary metabolism and in glycoconjugate biosynthesis and processing. In this paper, the reasonable three-dimensional molecular model of AglA was generated by homology modeling. This modeled protein is divided into five major structural domains, and the catalytic domain is classical (β/α) 8 barrel with the active site pocket positioned at its C-terminal side. With analyses of conserved residues and overlay of homology structures, the residues Tyr 662, Tyr527, Glu521, His238 and Tyr235 was predicted as the main substrate binding sites, and residues Asp490, Glu493 and Asp660 were deduced to be the acid/base catalytic residues.
Fractals and Catastrophe Analysis of Fatigue Crack Propagation for Sample by Plastic Deformation
Authors: Yao Yu Xin
Published: December 2011

Fractals and catastrophe analysis are applied to analyze photos of the law of crack of three sets of fatigue samples under different stress cycles. The results indicate that the law of crack has fractal characteristics. For undestroyed samples, the law of crack appears and develops, and the fractal dimension tends to be constant eventually. For destroyed samples, fractal dimension development is divided into four stages, that is, increasing gradually, increasing stably, decreasing stably and decreasing rapidly to the approximate value of one. When rupture occurs, the catastrophe point is the corresponding number of stress cycle.
Application of GM Yield Criterion in Plastic Zone of ModeⅠCrack and Burst Pressure for Pipeline
Authors: Zhao De Wen , Li Can Ming , Lan Liang Yun , Zhang Shun Hu
Published: December 2011

Based on GM yield criterion, the analytical solutions for shape and size of mode I crack tip plastic zone and the burst pressure for X70 pipeline steel are derived. Comparing the solutions with those based on Mises and Trasca criteria shows that under plain strain condition the area of plastic zone on GM is between Tresca and Mises solutions, and very close to Mises one. Among the areas Tresca’s is the largest and Mises is the smallest and all three zones are dumbbell shaped. However, for pipeline burst pressure based on Tresca criterion is the smallest and that on Twin shear stress criterion (TSS) is the largest, those on GM and Mises are also very close to each other and lie between Tresca and TSS results.
Discussion of the Evaluating Criterion of 400°C Low Cycle Fatigue Life under Multiaxial Stress States
Authors: Zhang Wen Xiao , Gao Guo Dong , Mu Guang Yu
Published: December 2011

By the investigation of the 400°C low cycle fatigue behavior of 4 kinds of notched cylindrical specimens made 2.25Cr-1Mo stee1. The high temperature low cycle fatigue life was evaluated by the criterons of equivalent range. The results show that equivalent criterion for evaluating high temperature low cycle fatigue life has its experimental and theoretical foundation, but further investigation is still needed．
The Lattice Stability of Ti, Zr and Hf in an Ultra-Soft Pseudopotential Method of the First-Principles
Authors: Tao Hui Jin , Yin Jian
Published: December 2011

The lattice constants, total energies and densities of states of Ti, Zr and Hf in ⅣB group with different crystalline structures have been calculated, and the results have been compared with the results of the projector augmented wave (PAW) method in first-principles, CALPHAD and experiments. It is found that the results of lattice stability in this paper agree completely with those of the PAW method in first-principles and agree well with those of CALPHAD. Further analyses of lattice stability from electronic structures show that the crystalline Ti,Zr and Hf with hcp structures have the obvious character of stable phases, but fcc and bcc structures have the character of metastable and unstable phases, agreeing with the results of total energy calculations. It is found from the analyses of atomic populations that the transiton numbers of electrons from the s state to the p and d states for the hcp, fcc and bcc crystals decrease with the increase in elemental period, and the transiton number of electrons from the s state to the p state decrease dramatically, but the transiton from the s state to the d state increase dramatically, leading to much more number of electrons in the d state than that in the s or p state, stronger cohesion or higher cohesive energy between atoms in heavy metals and accordingly the stabler lattice in these heavier metals.
Experimental Investigation of the Phase Equilibria of Al-Zn-Ti System in Al-Rich Corner at 400 °C
Authors: Luo Qun , Jin Feng , Li Yang , Li Qian , Zhang Jie Yu , Chou Kuo Chih
Published: December 2011

The phase equilibria in Al-rich corner of the Al-Zn-Ti ternary system at 400 °C were determined by means of optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS) and X-ray powder diffraction (XRD). The results showed that this section consisted of three ternary-phase regions, namely, L+(Al)+τ, Ti2Al5+τ+(Al) and Ti2Al5+TiAl3+(Al). The XRD patterns and EDS confirmed that a Ti2Al5-structured phase with containing 4 at.% Zn was stable at 400 °C. Furthermore, the ternary new phase (τ phase) was identified in samples and in equilibrium with (Al), Ti2Al5 and liquid, respectively.
The Electronic Properties of Al-, P-Doped and Al, P Co-Doped Boron Nitride Nanotubes
Authors: Sun Miao , Wu Gong Lian , Ye Ting , Zhang Hui , Yang Zhao Di , Li Ze Sheng
Published: December 2011

The electronic properties of Al-, P-doped, and Al, P co-doped in a (6, 6) BN nanotubes were obtained using the first principle calculation based on the density functional theory. For the doped BNNTs, the structures are with ignorable deformation observed around the doping atoms. The analysis of the formation energies shows that aluminum replacement to be favorable, particularly in the case of the low concentration, and the stability of nanotubes has nothing to do with the doping position. The electronic band structure and DOS for the systems of Al-, and P-doped BNNTs all behave as impurity-doped widegap semiconductor. And as to the P-doped BNNTs, the conductivity becomes stronger with the higher concentration. Whereas, the results of the system of Al, P co-doped BNNTs illustrate that the electronic properties of nanotubes have nothing to do with the doping positions of impurity atoms.
Quantitative Process Risk Analysis Based on Dynamic Simulation of Gas Gathering Process
Authors: Fu Jian Min , Zhao Dong Feng , Zhang Chao , Liu Yi
Published: December 2011

After nearly fifty years of development, HAZOP (Hazard and Operability study /analysis) has become the most widely used process hazard identifications method, basically covering all areas of petrochemical industry. As technology advancing and people continuing to increase safety requirements, HAZOP quantitative analysis has become a major trend. This paper gives an integration of traditional HAZOP procedure with Dynamic Simulation to quantify the HAZOP deviations and improve the operability of action required. A natural gas gathering process is selected to the application example. Uses the advanced process simulation software ASPEN HYSYS to set the modeling of the gas gathering process, and carry out the dynamic modeling in the light of main problems, and combing the dynamic simulation analysis gets the quantitative analysis results.
Quantitative Analysis of the Content of Substituent Group in Difunctional Polysiloxane
Authors: Sheng Chun Qi , Qu Zhi Rong , Jiang Jian Xiong , Lai Guo Qiao
Published: December 2011

In the present work, a new method for the analysis of the substituent group content in silicones by automatic elemental analyzer has been developed. Because of the number of substituent group effect on the physical and chemical properties about polysiloxane very much, its analysis by traditional techniques is tedious and costly. The novelty of this study relies on the fast and universal application of the automatic elemental analyzer to the quantitative analysis of the substituent groups. With this purpose, analysis of the quality percentage content of C and H in four different kinds of difunctional polysiloxane in automatic elemental analyzer, then compute the formula weight of a basic structure unit to deduce the content of the substituent group. The result was validated by 1H NMR.
The Cracks in the Residential Dwellings and their Treatment
Authors: Luo Ju Gang , Zhang Jin Yang , Xu Shan Jie
Published: December 2011

Cracks of different severities will appear on the beams, precast panels and building blocks and those found in current residential dwellings belong to the cracks due to temperature- shrinks and will not impact the structural safety mainly, nevertheless, they affect the appearance and decorative qualities, even cause leaking. Measures shall be done to treat them economically and practically.
Strengthen Mechanism of Hard-Drawn Cobalt-Base Elastic Alloy
Authors: Zheng Xiao Hui , Liu Gui Min , Du Jian Hua
Published: December 2011

The microstructure and tensile properties of cobalt-base elastic alloy Co40NiCrMo are investigated. The results show that, fcc structure is the crystal structure of Co40NiCrMo alloy after solution treatment and hard-draw. The slipping and twinning are the modes of plastic deformation during the hard-draw. Twinning is the main deformation mode of Co40NiCrMo alloy after hard-draw when more deformation is made.
Hydrogen Atom Adsorption on α-Al2O3(0001) Surface from First Principles
Authors: Hu Jian Gong , Zhang Yi Sheng , Jia Li Chao , Zhu Bin , Yang Hong Guang , Zhan Qin
Published: December 2011

First-principles calculation based on the density functional theory in the generalized gradient approximation was adopted to systematically investigate the α-Al2O3(0001) surface structure and the adsorption of H atom on the α-Al2O3(0001) surface. The calculations show that the O atop site is the energetically most favorable adsorption site at low coverage: at the H coverage of 1/6 ML (monolayer), the adsorption energy reaches up to7.61eV; in the regime of higher H coverages, the H atoms prefer to form atom cluster on the α-Al2O3(0001) surface, and the adsorption energy on the α-Al2O3(0001) with a pre-adsorbed H atom gets smaller, which illustrates that α-Al2O3that can prevent the penetration of hydrogen. With the increase of H coverage, the dipole moment reduces, which leads to a large decrease in the work function.
Microstructure and Mechanical Properties of TiB2/Al Composites
Authors: Chen Shuai , Zhao Yu Tao , Jin Hua
Published: December 2011

Abstract:TiB2/Al composites were prepared by the melt in situ reaction fabrication using Al-3B master alloy and Ti powder as the reactive materials. The phase composition and the microstructure of the as-prepared composites were investigated by XRD, SEM. The results indicate that the reinforcements are TiB2 and a small amount of Al3Ti. TiB2particles are in the shape of irregular polygon or rectangle, and its size is 0.5-2μm. Compared with the matrix material, the ultimate tensile strength, microhardness of as-prapred composites increase by 51%, 68.8%, 85.2%, and 33.4%, 43.8%, 55%, respectively. However, the elongation decrease with the volume fraction of the reinforcements increased.