bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Surface Deflection Controlling in Cylinder Shallow Shell Forming
Authors: Sun Zhen Zhong , He Wei Feng , Chen Hai Bin
Published: November 2010

The surface deflection is an important disadvantage issue in the automobile outer panels forming. It can be controlled effectively through forming process. It is difficult to study the surface deflection because of the complexity of automobile panels. In this paper, a model of cylinder shallow shell is founded, and the measured method and evaluated standard of surface deflection for drawing parts are presented. The influence law of process techniques on surface deflection such as binder force, draw-bead, local force, and shape of blank-hold surface is achieved, which give a basic reference for controlling surface deflection.
Application and Analysis Chilling Ceiling Combined with Displacement Ventilation System in Office Buildings
Authors: Wang Ling , Qi Wei Yang , Liu Ri Chao , He Shun Jun
Published: November 2010

Using the method of computational fluid dynamics (CFD), numerically simulates office building with chilling ceiling /displacement ventilation (CC/DV) and analyzes indoor airflow velocity field, temperature field and thermal stratification height of the building. Consider that the CC/DV system can improve indoor air quality and save energy. And the CC/DV system could solve many constraints of displacement ventilation system. when the cooling load is large, due to the limit of air supply and temperature supply the displacement ventilation system can not be used, but the CC/DV system could well satisfied the requirement of body. The CC/DV system also has the problem of lower thermal stratification height because the chilling ceiling has a lower temperature.
Preparation of Nanometer Al (OH)3 Powder Using Coal Gangue by Polyacrylamide Dispersant-Carbonization Method
Authors: Tang Zhong Hua
Published: November 2010

Polyacrylamide after the molecule degradation is used as dispersant and the coal gangue as the raw material to prepare the nanometer Al (OH)3 powder in this paper. Calcining at high temperature to activate coal gangue and controlling the change of C2S crystal were adopted to prepare the self-pulverized material of coal gangue. When the aluminum component part is distilled with NaAlO2 form from the self-pulverized material of coal gangue by using 8% Na2CO3 solution, the high-pure superfine aluminum hydroxide powder is prepared by using the high efficiency dispersant carbonization method. When the influence factor that the high efficiency dispersant carbonization method prepares high-pure superfine aluminum hydroxide powder has been studied, it has been found that the optimum condition of the high efficiency dispersant carbonization method can prepare the high-pure superfine aluminum hydroxide powder. The average granularity of aluminum hydroxide powder that has been prepared is less than 100 nm and the purity is more than 99.9%, for a new way has been opened up for the high value utilization of coal gangue.
Process of Ni-P Electroless Deposition on SiCp/Al Composites from Acid Bath
Authors: Li Jian Zhong , Tian Yan Wen , Li Ying , Wang Xiang Rong
Published: November 2010

The initial nickel deposition for the direct electroless nickel plating on active SiCp/Al composites is critical. So it is necessary to investigate the process of the electroless Ni-P plating deposition on SiCp/Al composites by means of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). In addition, the mass gain/loss in the initial nickel deposition process was measured by using the electro-balance. The results show that after being treated using phosphoric acid and hydrogen peroxide, the compositions of SiCp/Al composites substrate contains Al, SiC and Al2O3. The Al2O3 film was gradually corroded by the plating solution. And then Ni-P coating was deposited on the substrate without Al2O3 film during the initial electroless plating process, which was mostly growing on the boundary between the SiC particles and the Al crystal of the activation substrate, and then came to two sides. After that, the Ni-P coating growth rate to cover with the SiC particles and Al crystals was prior to the Al2O3 film. The electroless plating was in company with the substrate corrosion, but the electroless plating rate catalyzed by the exchanged nickel was more than the substrate corrosion rate.
Microstructure and Mechanical Properties of High Strength Hot-Rolled TRIP Steel Containing Vanadium
Authors: Hou Xiao Ying , Xu Yun Bo , Wu Di
Published: November 2010

Laboratory hot rolling experiments on a low-carbon TRIP steel containing vanadium have been carried out to study the microstructure characteristics and mechanical properties. The results showed that the multiphase microstructure with ferrite, granular bainite and retained austenite could be obtained if the finish rolling initial temperature was properly decreased and the finishing temperature was controlled in the range of Ae3~ Ar3, and the tensile strength achieved 930 MPa or above. The average ferrite grain size was about 4.5 μm in this experiment, the vanadium nitrides and vanadium carbides precipitated dispersedly within ferritic grains or at grain boundaries, and the higher dislocation density existed in ferrite matrix. EBSD analyses revealed that the high angle boundaries accounted for a large proportion and the misorientation angles were within the interval between 29° and 60° mostly. When the finishing temperature was 800°C and the final air cooling temperature was 630°C, the steel had excellent mechanical properties, which was characterized by combination of high strength(about 930MPa), high elongation(21.7%), low yield/strength ratio(0.49) and as well as high work-hardening exponent(0.23).
Tribological Properties of Cu Based Friction Composites with In Situ Synthesized TiC Filler
Authors: Chen Bai Ming , Zhang Zheng Yu , Wang Ming Xu , Han Guo Cai , An Liang
Published: November 2010

The Cu based friction composites using graphite as solid lubricant with different weight rations of Ti, i.e. 8 wt.%, 12 wt.%, 16 wt.%, 20 wt.%, were sintered by powder metallurgy (P/M) method. The structure of the composites was characterized by X-ray diffraction (XRD) and the tribological properties was studied on block-on-ring tester. XRD results verified presence of TiC phase which was in-situ synthesized through reaction of Ti and graphite in the composites, and the content of TiC was increased with the increased Ti content. The in-situ synthesized TiC phase which was fine and distributed uniformly improved tribological properties of Cu based friction composites significantly. The hardness, wear rates and friction coefficient of composites were increased with increasing amount of in-situ synthesized TiC.
The Study of Effects of Temperature on Contact Strengths of Thick-Walled Cellular Solids
Authors: Xie Fang , Liu Zuo Min
Published: November 2010

In order to investigate the effects of temperature on the contact strengths of the thick-walled cellular solids, materials of H59 brass was chosen for the preparation of cylindrical specimens which contain single pore, double pores, three pores and four pores respectively. The contact strengths of these specimens were determined in a YE-600 hydraulic testing machine at 20°C (room temperature) and 300°C respectively. The experimental results show that: the temperature had great effect on contact strength of the thick-walled cellular solids, mainly reflected in loading capacity and deformation, when the temperature increased from 20°C to 300°C, the loading capacity of the solids were reduced by 10.94 to 14.85% and the corresponding deformations were increased by 97.50 to 108.33%, which depended on the micro-pores structures. Furthermore, the effects of temperature on cracks out-look mainly reflected in cracks deepening with temperature. When the temperature increased from 20°C to 300°C, the depth of the cracks increased about 78 to 110%, which also depended on the micro-pores structures. However, temperature had little effect on the initiating position of the cracks for all micro-pores structures discussed from 20°C to 300°C.
Comparative Study on Four Different Methods for Measuring the Dynamic Modulus of Elasticity of Acer Mono Wood
Authors: Xu Hua Dong , Wang Li Hai
Published: November 2010

The dynamic modulus of elasticity (MOE) of forty one small Acer mono clear wood specimens was tested via stress wave, ultrasonic wave, edgewise vibration and flatwise vibration method respectively in laboratory. Then the static MOE of these specimens was measured with static bending test. The correlations between dynamic and static MOE were analyzed using linear regression method, and the difference of various methods was discussed using paired t test. The results show that the dynamic MOE of wood measured by four methods described above are higher than the static MOE, but their linear correlation is significantly strong. Thus, it is feasible to estimate static MOE using these four methods. Additionally, the mean of paired difference between static MOE and dynamic MOE tested by flatwise vibration method is least, and the correlation highest. Therefore, it is better to use flatwise vibration method to estimate static MOE of wood.
Design Allowable for Durability Analysis of Advanced Composites
Authors: Fan Xue Ling , Qin Wen Jun
Published: November 2010

An allowable design method is presented, along with its experimental validation, to obtain engineering-standard design allowable for fatigue life evaluation of advanced composites. A small sample test method for stress/life curves was established to overcome these issues based on the regression analysis theory. Statistically-based design values, such as the B-basis value, the Anderson-Darling test statistic and the observed significance level, were obtained depends on the characteristics of the composite material test data. For evaluation of the fatigue life of advanced composites, the S-N curve-fitting parameters are obtained using the linear heteroscedastic regression method based on experimental data. Another advantage of this method is that all the test data at different stress levels can be analyzed coinstantaneously, which greatly saved the experimental efforts and specimen for confidential statistical results. Finally, an experimental test program has been conducted on typical laminate composites to generate statistically meaningful data for durability design. The numerical results show that the proposed method can be used as a guide to obtaining design allowable for durability analysis of advanced composite structures.
Effect of Ammonia Etching on Catalyst Nanoparticles Formation for Growth of Aligned Carbon Nanotubes
Authors: Li Gang
Published: November 2010

The effect of ammonia etching (AE) pretreatment on the formation of catalyst nanoparticles from homogeneous Ni films deposited by sputtering coater for carbon nanotubes (CNTs) growth is investigated systematically. It is shown that the size and distribution of the nanoparticles depend mainly on the AE pretreatment temperature and time. It is observed that Ni catalyst film is agglomerated by AE pretreatment, resulting in the formation of Ni nanoparticles. We have found a critical temperature and time for AE pretreatment processes to obtain catalyst nanoparticles with the appropriate size and high density. The densely aligned CNTs were successfully grown at 800-850 °C on such nanoparticles by thermal Chemical vapor deposition (CVD).
Fabrication and Characterization of a Feldspar-Alumina for Dental Ceramic
Authors: Zhang Guang Lei , Qin Guo Qiang , Zhang Yuan Hua , Cheng Pu , Shao Chang Tao
Published: November 2010

Feldspar-alumina dental ceramics were produced by impressed sintering method and characterized by X-ray diffraction and scanning electron microscope techniques. The machinability of the obtained alumina ceramics was evaluated by grinding capacity in the simulative grinding experiment. The results show that an appropriate amount of feldspar additive can reduce the sinter temperature and improve density, bending strength and machinability of alumina dental ceramics. Under 10 wt% feldspar and 1450 °C sinter temperature, the relative density and bending strength of ceramic reached 93.62% and 235MPa, respectively.
Research on Stamping Forming and Spring-Back of Automotive Panel
Authors: Chen Xiu Long , Shan Huai Bo , Liu Xi Hua , Wang Gui Lian
Published: November 2010

In order to solve spring-back problem of the stamping forming process, A method for stamping forming and spring-back process simulation of automotive panel by finite element technologies was proposed. The solid model of automobile right side strengthening panel was created in UG software and transmitted to Dynaform. The stamping forming and spring-back process simulation were realized by using Dynaform. The distribution of strain, the variety of the sheet thickness and the spring-back were analyzed. The maximum stress or strain, the minimum thickness and the maximum spring-back were obtained. The simulation results can reflect the real stamping forming of the strengthening panel, and forecast the possibly spring-back value in stamping process. This research can optimize the stamping process and provide strong references for the design of the automotive panel die.
Preparation and Characterization of Cu Nano-Powders by Hydrothermal Decomposition and Hydrogen Reduction Process
Authors: Li Zai Yuan , Gao Yun , Jin Duo , Liu Jie , Zhai Yu Chun
Published: November 2010

In this paper, Cu nano-powder was used to reduce CuO nano-powder by hydrogen reduction process, which was prepared by hydrothermal decomposition method taken CuSO4•5H2O and NaOH as raw materials. The reaction conditions of CuO nano-stick were that concentration of CuSO4 liquor was 0.1mol•L-1, concentration of NaOH liquor was 5mol•L-1, dropping speed was 50ml•min-1, pH value of reacting terminal was 12, stirring speed was 1200 r•min-1, reacting temperature was 60°C, reacting time was 30min. The CuO stick longness was 200nm, diameter was 30nm. The reaction conditions of CuO nano-boll were that dropping speed was 50ml•min-1, pH value of reacting terminal was 7, stirring speed 100 r•min-1, reacting temperature was 80°C, reacting time 30min. The diameter of CuO nano-ball was 50~100 nm. The Cu powder was prepared with materials CuO tick by hydrogen reduction in closed circular system. The higher the temperature, the reaction speed is faster. Hydrogen reduction time was 400s in reacting temperature 240°C. The Cu powder’ size was less than 100nm.
Preparation and Characterization of Ni90Ag10 Composite Nano-Powders by Chemical Co-Precipitation Hydrogen Reducing
Authors: Li Zai Yuan , Gao Yun , Jin Duo , Liu Jie , Zhai Yu Chun
Published: November 2010

The Ni(OH)2-Ag2O powders were prepared with materials NaOH, NiNO3•6H2O and AgNO3 by chemical co-precipitation method. The reaction conditions were that Ni2+ solution concentration 0.0943mol•L-1 and Ag+ solution concentration 0.0943mol•L-1 in the Ni2+-Ag+ composite solution concentration, the NaOH solution concentration 4mol•L-1, dropping speed of the NaOH solution 50ml•min-1, the pH value of reacting terminal 13, the stirring speed 1200r•min-1, the reacting temperature 25°C, the reacting time 60min. Ni(OH)2-Ag2O composite powders’ size was 2-50nm. Ni-Ag composite powders were prepared with materials Ni(OH)2-Ag2O composite powders by hydrogen reduction in closed circular system. Ni-Ag composite powders’ size was 2-40 nm.
Construction of Discarded Refrigerator Recycling System Based on Reverse Logistics in Harbin
Authors: Li Yan , Xu Heng Qin
Published: November 2010

As an important part of the social logistics, reverse logistics plays an important role in socio-economic development. In this paper, we took discarded Haier refrigerator as the object of study, and investigated the operating conditions of electrical appliance industry and recycling situation of discarded appliances enterprises in Harbin. Through the reference to the domestic and international recycling technology of discarded refrigerators, we analysed the haier home appliance in financial crisis in Harbin, introduced the concept of reverse logistics and constructed the recycling system of Haier refrigerators based on reverse logistics. After the analysis of the system, we find out its feasibility and practical operability and prospect the future research of logistics industry.
Effect of TSCR Process on Cold Rolling Texture of Fe-3% Silicon Steels
Authors: Yu Yong Mei , Zhang Yuan Xiang , Li Chang Sheng , Wang Guo Dong
Published: November 2010

The effect of hot rolling parameters including different hot rolling reduction, soaking time of ingots and chemical composition on cold rolling texture by TSCR process was studied. The result indicates that α fibers and γ fiber texture were affected by hot rolling reduction, and oriented density αfibers texture increases with hot rolling reduction rate increasing, and the texture components is same in the surface and different in the center. The strength of γ fiber texture, from {111}<110>to {111}<112>, is decreasing trendency for ingot soaked for 10min and 20min. however, changing trendency from {111}<110>to {111}<112> in 1/8 thickness and 1/4 thickness of cold rolling strip for ingot soaked for 30min. The volume fraction of {111}<112> is rising with the ingot soaked time and the maxium is 3.5 percent, and the volume fraction of {111}<112> is higher in every layer of cold rolling strip whose chemical composition includes Sn than without Sn, the volume fraction of {111}<112> is higher in 1/8 and 1/4 layers than the surface and center layers.
Experimental Investigation of Heat Transfer Enhancement of the Heat Pipe Using CuO-Water Nanofluid
Authors: Li Dong Dong , Zhao Wei Lin , Liu Zong Ming , Zhu Bao Jie
Published: November 2010

This paper presents an experimental investigation of the heat transfer characteristics of the heat pipe with CuO-water nanofluid. For this purpose, CuO nanoparticles of 30 nm size were dispersed in distilled water to form stable suspension containing 0.1% ~ 2.0% mass concentrations of nanoparticles, and then the heat pipe was produced after CuO-water nanofluid was added in it as the working fluid. Experimental results show that the use of CuO-water nanofluid hold a lower start-up temperature and shorter start-up time for the evaporation section of the heat pipe compared to distilled water. Their heat transfer performance of the evaporation section and condenser section has been improved than that of distilled water. The heat transfer coefficient of nanofluid is higher than that of the base liquid and found to increase by 29.4% and 125.0% for the mass concentration of 0.5% compared with the heat pipe using distilled water while the input power ranging from 15W to 45W. By examining the thermal resistance, it was found that the thermal resistance has been significantly decreased compared with the heat pipe with distilled water. The thermal resistance of heat pipe using CuO-water nanofluid at a mass concentration of 0.5% is 0.36K/W when the input power is 45W, while the thermal resistance of heat pipe using distilled water is 0.80K/W. Further analysis indicates that the heat pipe using CuO-water nanofluid at 1.0% mass concentrations has the best heat transfer performance.
Study of Synthesis and Properties of Spinel LiNi0.4Mn1.5Cr0.1O4 as Cathode for Lithium Ion Batteries
Authors: Liu Guo Qiang , Liu Guang Yin , Shi Xiao Yan
Published: November 2010

Spinel compound LiNi0.4Mn1.5Cr0.1O4 was synthesized at different reaction temperature. The optimum temperature was 900 0C. The product exhibited good electrochemical properties. It delivered capacity of 128.2, 124.1 and 116.8 mAh g-1 at 0.2, 0.5 and 1C, respectively. The capacity retention was 98%, 99% and 99% after 30 cycles, respectively. The electrochemical property of compound LiNi0.4Mn1.5Cr0.1O4 was better than that of LiNi0.5Mn1.5O4.
Progress in the Preparation of Composites Based on the Nonmetallic Fractions Recycled from Waste Printed Circuit Boards
Authors: Liu Wei Qiao , Wang Xing Xing , Lei Wei Ning , Shang Tong Ming , Zhou Quan Fa
Published: November 2010

From the use of renewable resources and environmental protection, recycling of waste printed circuit boards (PCBs) receives wide concerns as the amounts of scrap PCBs increases dramatically. However, the recycle technology for waste PCBs in China is still immature. Previous studies focused on metals recovery, but resource utilization for nonmetallic fractions (NMFs) is relatively fewer. In this paper, the physical properties of the recovered nonmetallic powder is briefly introduced. The preparation of composites including organic and inorganic composites through the recycling NMFs was reviewed. In addition, the research directions of preparation of composites based on recycling NMFs were put forward. Firstly, the study on the reaction mechanism of composites preparation should be strengthened to explore the reasons why the additional quantity and particle size of NMFs powder have effects on the properties of composites. Secondly, a suitable coupling agent should be chosen to improve the the interface compatibility between the NMFs and matrix.
Characterization of Fluorinated Hβ Zeolite with NH4F
Authors: Tian Zhen , Bing Nai Ci
Published: November 2010

Fluorination of the zeolite has been known as a useful method to modify its acidity and surface performance. In this paper, a set of zeolite Hβ were impregnated with aqueous solution of NH4F. The effects of NH4F impregnation on the structure and acidity of Hβ was investigated by XRD, BET measurements, NH3-TPD, and Py-IR. The change of specific surface area and pore volume of the fluorinated samples with NH4F can be attributed the reaction of NH4F with non-framework and framework aluminum. The fluorination increases the strength and changes the distribution of the acid sites; the fluorination also leads to the decrease of the total acid sites and the Brönsted acid sites due to the dealuminization of the samples and the substitution of the OH- by fluorine atoms.
Synthesis and Characterization of Cu(II), Zn(II) Dendritic Metal Complexes
Authors: Wang Jun , Zhang Peng , Chen Shuai , Li Cui Qin
Published: November 2010

A new kind of dendritic-salicylaldehydeimine ligand was synthesized with 1.0G polyamidoamine and salicylaldehyde through schiff reaction, and further formed two kinds of dendritic metal complexes by complexing Cu and Zn. The dendritic-salicylaldehydeimine ligand and its metal complexes were characterized by elemental analysis, IR, NMR and UV. The results indicate that two kinds of dendritic metal complexes with stable structure have been synthesized by complexing Cu and Zn, the yield were 88.2% and 65.2% respectively; Intra-molecular hydrogen bond between the hydroxyl H atom of ph-OH and the N atom of >C=N- has been formed in the ligand; The structures of complexes agree well with the theory.
Warm Tension Flow Stress Model of DP Steel LTWB Based on KS Function
Authors: Guo Yu Qin , Chen Wei , Li Fu Zhu , Yang Xin
Published: November 2010

For high strength LTWBs used widely in light-weigh auto body production, warm forming process has become an effective solution to improve their forming performance and reduce springback. While the flow-stress model of LTWB warm forming is vital to determine reasonable warm forming process scheme, and predict precisely LTWB forming status and springback. In the present work, aimed to 1mm thickness DP steel LTWB (B340/590DP), a warm tension flow-stress model is proposed based on KS function and bi-linear interpolation by analyzing characters of the stress-stain curve obtained from warm tension test. Via comparing the model prediction results with those of other existing flow-stress models and experiment data, it is verified that the proposed model can not only give more closely the stress-strain relationship than other models during uniform plastically deforming and plastic yielding, but also can indicate the occurrence of necking phenomenon.
Bearing Capacity of Frame’s Column Strengthened with Addition Flange Wall
Authors: Wang Ru Heng , Jia Bin , Guo Wen , Fan Chao
Published: November 2010

A large number of frames damaged due to the poor lateral stiffness in “5.12” earthquake. Additonal flange wall could effectively improve the lateral stiffness. This paper analyzed the behavior capability of special-shaped column of the practical engineering structures, meanwhile, obtained N-M curve, Mx-My curve and M-φ of biaxial eccentricity compression based on numerical integration method.The results show that,the failure mode of special section column after reinforcing and rectangular column under the biaxial eccentricity compression are conform,including fail in tension or compression and the limit failure. When the axial compression ratio is quite slightly,and section eccentric tension destruction, the thrust increases, the anti-bending ability increases.When section bearing destruction, along with axle strength enlargement, the anti-bending ability reduces.And the results reveal the axial compression ratio could influence the bearing capacity and ductility of frame’s column obviously.
Molecular Dynamics Study of Size Effect on Uniaxial Tension of Single Crystal Cu Nanowires
Authors: Ma Xiao Chun , Yin Ji Hui , Zhang Jun Jie
Published: November 2010

The uniaxial tensions of single crystal Cu nanowires (NWs) with different circular cross-section radiuses are simulated by molecular dynamics (MD) method. Atomic interactions in Cu NWs are described by EAM potential. The results show that the plastic deformation of NWs under uniaxial tension is dominantly controlled by dislocation nucleation and gliding. The mechanical properties of NWs are size-dependent. The NWs with larger radius of cross-section possess higher strength and ductility. Furthermore, the site of neck formation and following break of NWs has strong dependence on size scale of NWs.
Influence of Segment Design of Shield Tunnel on the Magnitude of Joint Opening
Authors: Liu Yin , Huang Hong Wei , Zhang Dong Mei
Published: November 2010

It is obviously a simplification to consider the tunnel lining as uniformly permeable.In reality it is more likely that there are specific leaks assocoated with segmental lining joints. In the case of in situ concrete linings, construction joints can provide leakage paths, accounting for most of the water leakage. In this paper, based on the mechanical model of segment joint, the analytical expression of magnitude of joint opening was developed, in light of which, the occurrence of water leakage through the joint system can be judged. Taking the metro line No.1 in Shanghai as an example, effects of such parameters as joint flexural stiffness, bolt location, bolt stiffness, bolt prestress, etc. on the magninitude of the joint opening were analyzed respectively through the analytical solution. The results not only help us realize the influence mechanism of segment design on the magnitude of joint opening of the segmental linings, but also provide the guidance for waterproof design of the shield tunnel.
Effect of Ni Addition on the Formation and Growth of Intermetallic Compound at Eutectic SnBi/Cu Interface
Authors: Kang Tian You , Xiu Yu Yan , Xu Bo , Liu Chun Zhong , Tong Wei Ping
Published: November 2010

The reactions between Cu and the eutectic SnBi (Sn58wt.%Bi) solder alloy with and without 1wt.%Ni addition were investigated in this paper. After as-reflowed process, the IMCs formed in the Sn58wt.%Bi/Cu and Sn58wt.%Bi1wt.%Ni/Cu joints were Cu6Sn5 and (CuNi)6Sn5, respectively. During aging process, the thickness of the IMC layers formed at each solder/Cu joint increased, and a new layer Cu3Sn formed adjacent to the Cu substrate. It was found that 1wt.%Ni addition in Sn58wt.%Bi solder alloy could slightly enhance the growth rate of the total IMC layer, but effectively reduce the growth rate of Cu3Sn layer during aging process. The growth behavior of IMC layer for each joint followed the diffusion-controlled mechanism during aging.
Failure Factor Research of Composite Laminates Containing Holes Based on MSC.Nastran
Authors: Feng Zhen Yu , Yang Qian , Yin Xing Yan , Chen Zhao Chen , Zou Tian Chun
Published: November 2010

With the extensive use of composite materials in aviation industry, the research of holes which affect composite residual strength has become very important. Based on MSC.Nastran, the stress of each laminate unit was calculated. Failure factor of composite laminates containing holes were calculated with the Tsai-Wu failure criterion. In this paper, the influence of hole shape and size on the composite laminate failure factor under compressive loading was studied. The relationship of hole shape, size and residual strength of composite laminates was briefly discussed. The results show that, under compressive loading, the stress concentration appears near the hole, there is a proportional relationship between the failure factor and hole size, the hole size and residual strength is the inverse relation.
Application of Different Post-Treatments to Improve the Leaching Resistance of ACQ-D Treated Wood
Authors: Yu Li Li , Cao Jin Zhen , Tang Zhen Zhong
Published: November 2010

Chinese fir (Cunninghamia lanceolata Hook.) and Mongolian Scots pine (Pinus sylvestris Linn. var. mongolica Litv.) with dimension of 19.019.0450.0 mm were treated with two concentrations of amine copper quat-type D (ACQ-D) solutions (0.5%, 1.0%) respectively and post-treated with three different methods including humidity chamber, drying oven and hot water bath. The effects of these variables on copper leaching from ACQ-D treated wood were investigated according to the leaching test of AWPA E11. The results showed that post-treatment could improve the leaching resistance of ACQ-D treated wood effectively compared to the specimens those were leached immediately after impregnation. After some promising post-treatments, copper leaching from the treated wood was not only associated with the joint effects of retentions, wood species and different locations in the treated wood, but also influenced by the special fixation mechanisms in different post-treatments.
Stress Distribution in the Vicinity of Thermally Grown Oxide of Thermal Barrier Coatings
Authors: Fan Xue Ling , Qin Wen Jun
Published: November 2010

Finite element simulation of stress distribution of thermal barrier coating system (TBCs) is presented. Two dimensional periodic unit cells are used to examine the stress development and critical sites with high potential of cracking during thermal cycling. During cooling, high tensile out-of-plane stresses in the peak of the thermally grown oxide (TGO) are formed, which lead to crack initiation in the vicinity of TGO and the interface. At the same time, high compressive stresses developed in the valley domain. The influence of crack within the top coat in the vicinity of the TGO is also investigated. The finite element analysis shows that crack seriously affects stress field development and the thermal-mechanical behavior of TBCs. Based on the finite element analysis results one can conclude that imperfections and its development should be always considered to be a crucial parameter for TBCs life.
Experimental Study on Extraction of Vanadium from Contained Vanadium Solution
Authors: Chen Xiang Yang , Lan Xin Zhe , Song Yong Hui , Yang Shuang Ping
Published: November 2010

Vanadium is an important alloying elements and structural materials, a large part of vanadium was extracted from stone coal. The resources of stone coal are very rich in China. It's an important development direction to extract vanadium in stone coal. The stone coal in Shaanxi Province Shanyang County has been studied. Vanadium was extracted by HDEHP in this experiment, which is in the sulfuric acid solution leaching system. The paper researched the influence of concentration of di(2-ethylhexyl) phosphate (HDEHP), pH, the extraction time, the extraction stages, the phase ratio for the extraction ratio of vanadium, the extraction capacity of organic phase and the extraction isotherm. The best technical parameters: 20% di(2-ethylhexyl) phosphate (HDEHP), TBP 5%, sulfonated kerosene 75%(volume concentration), pH=2.5, phase ratio Vo:Va=1:5 and the extraction time is 5 min, extraction of 5 stages level. The extraction ratio of vanadium is 98.57% from the solution of 2.9658 mg/ml vanadium in that technical parameter. The best stripping of vanadium process parameters: the stripping agent for 1 mol/l of sulfuric acid, phase ratio Vo: Va = 5:1, the stripping time is 5 min, the stripping of three stages. Under this condition we may strip loaded organic phase which contain the vanadium 9.0266 mg/ml, the stripping rate is 99.73%.
Electron Back Scattering Diffraction Analysis of A357 Alloy Modified by Sr
Authors: Chen Zhong Wei , Zhang Hai Fang , Zhao Jiang Chao
Published: November 2010

Microstructure of A357 alloy modified by Sr has been investigated by the Electron Back Scattering Diffraction (EBSD) mapping technique using a Field Emission Gun Scanning Electron Microscopy (FEG-SEM). An appropriate sample preparation technique by ion milling was applied to obtain a sufficiently smooth surface for EBSD mapping. Results show that the eutectic morphology in microstructure of A357 alloy modified by Sr was changed to fine fibrous, and the grain size was refined. By comparing the orientation of the aluminum in the eutectic to that of the primary aluminum dendrites, the nucleation and growth mechanism of the eutectic solidification in A357 cast alloy was determined. The eutectic Si phase of the modified sample nucleates on the heterogeneous nuclei located in the region between primary α-Al dendrites and grows up, while the eutectic Si phase of the sample without modification nucleates on the primary α-Al dendrites and grows up.
Kinetics and Thermodynamics Studies on the Decompositions of Phosphogypsum in Different Atmospheres
Authors: Ning Ping , Zheng Shao Cong , Ma Li Ping , Du Ya Lei , Zhang Wei , Niu Xue Kui , Wang Fei Yu
Published: November 2010

In this study, the decomposition of phosphogypsum at different atmospheres of pure CO, N2 and 10% of CO were investigated to gain knowledge about the thermal decomposition of phosphogypsum. It was found that the starting decomposition temperature is 820°C in pure CO, the temperatures are 1080°C for N2 and 890°C for 10% of CO, respectively. Quantitative XRD method was applied to determine the amounts of CaSO4, CaO and CaS in the residues. The results indicate that CaS was mainly formed during Phosphogypsum decomposition in pure CO. In N2 CaO is the main residue from reactions, accompanying a small amount of CaS, and there are CaO and CaS in the decomposed productions, in 10% of CO. Moreover, The Starink,Kissinger and Flynn-Wall-Ozawa methods were used to calculate the kinetic parameters, respectively. The results have shown that the activation energy is in the range of 290.84-317.34 kJ/mol for in pure CO, 335.98-360.90 kJ/mol for 10% CO, 476.39 kJ/mol for N2.
Numerical Simulation Study on the Cold Rolling of Hollow Thread
Authors: Qi Hui Ping , Li Yong Tang , Liu Zhi Qi , Du Shi Wen
Published: November 2010

The cold rolling technology of thread was rapidly developed due to its high efficiency, low cost and perfect property of its production. But theoretical researches on the precise forming were very few, especially for the hollow parts. In the rolling process, empirical (trial and error) methods have been a mainly part. This is unfavorable for the development of the new technology. In this paper, numerical simulation of the cold rolling process of hollow thread was studied. The DEFORM soft was used to perform the simulation work. The stress field, strain field and velocity field in the workpiece were obtained. The change curve of the rolling force and the relation curve of tangential force and torque were obtained. The failure process of hollow thread in the rolling process was also simulated. The failure reason of thin wall thread in the rolling process was analyzed according to the change of effective stress in the workpiece. The result is well agreement with theoretical ones. The further research will be done to promote the application of numerical simulation in the cold rolling of hollow thread parts.
Quasi-Static Failure Analysis of Honeycomb Sandwich Beam with Composite Facesheets
Authors: Meng Li Qing , Wu Yan , Chen Shi Zhe , Shu Xue Feng
Published: November 2010

Sandwich construction consists of two thin composite or metal facesheets separated by a core material. Despite extensive researches on the sandwich constructions, their mechanical properties and failure behaviours are still not fully understand. The objective of the paper is to use a experimental and theoretical predicting failure mode for sandwich beam consisting of GFRP facesheets and Nomex honeycomb core. Two kinds of composite sandwich beams are observed in quasi-static three-point bending and indentation test.
The Distinctive Charm of Coating-Architecture in the Modern Urban Development
Authors: Han Li Xin , Han Jing , Sun Feng Ming , Huo Yu Jiao
Published: November 2010

In the development of modern cities, building decoration materials are like a hundred flowers in bloom with the rapid development of society and technology. Coating-Architecture becomes the conspicuous central point for its distinctive charm. This paper focuses on the superiorities of Coating-Architecture in various angels, such as architectural aesthetics, economy, construction and maintenance. It indicates Coating-Architecture do possesses an irreplaceable potential in the urban development.
The Case Study on SO2 Emission Factor from Iron and Steel Industry in Yunnan Province
Authors: Zhang Yan , Tang Xiao Long , Yi Hong Hong , Yu Qiong Fen , Li Kai , He Dan , Song Jiang Hao
Published: November 2010

The present status of iron and steel industry of China and Yunnan were given in this work. Base on the analysis of iron and steel industry of Yunnan, we choose two steel plants (marked plant A and plant B) as the typical factories to confirm the emission factor of SO2. The emission factor of SO2 was achieved by mass balance method. In steel plant A, the emission factor is 9.684 (kg-SO2/t-steel), after flue gas desulfurization, the factor dropped to 1.476 (kg-SO2/t-steel). It indicates that desulfuration of sinter flue gas is important to reduce SO2 emission. In steel plant B, the emission factor is 5.4(kg-SO2/t-steel) without desulfurization. However, according to Discharge Coefficients of Industrial Pollutants in the First National General Survey of Pollution Sources(Survey Handbook), the SO2 emission factor of plant B is 4.15(kg-SO2/t-steel). We can see the differences exist between Yunnan’s discharges of pollutants with national Survey Handbook. Because the national Survey Handbook represents the national average level and manufacturing technique and raw materials of various factories vary greatly within the country. So it’s necessary to confirm the emission factor for Yunnan province.
Experimental Research on Fatigue Behavior of Recycled Aggregate Reinforcement Concrete from Earthquake-Stricken Area
Authors: Yan H.Q. , Wang Qing Yuan
Published: November 2010

Aggregate obtained by breaking wasted concrete is called recycled aggregate. Recycled aggregate concrete (RAC) is a kind of practical and economic material to reuse the great amount of construction and demolition wastes, which has received many discussions nowadays.Its fatigue behavior is different from other concretes as a result of different property of the aggregate of recycled concrete and other concrete. In order to apply RAC more effectively, it is necessary to study its properties especially for those aggregates from earthquake-stricken area for post-earthquake reconstruction. Therefore, on the basis of experimental research, the fatigue behaviors and microstructure of recycled concrete are studied in this paper. The present paper deals with investigations on fatigue behavior of the axial and eccentric compression performance of recycled aggregate reinforcement concrete specimens which are made from different recycled aggregate proportion such as 0%、50%、100%. Then micro-structural observations of the specimens by means of scanning electron microscopy (SEM) were obtained. Based on the analysis of experiment results, it can be proved that it is feasible to apply recycled concrete to practical engineering.
Study on Main Cable-Shaped of Long-Span Suspension Bridge
Authors: Cai Lu Rong , Wang Rong Hui , Chen Kong Liang , Liu Chang Hai
Published: November 2010

The main cable is made of PPWS. Its large displacement and nonlinear mechanical properties are shown by their own elastic deformation and its geometry changes affecting the system balance. To get the real main cable-shaped of long-span suspension bridge, based on the finite element method, the element stiffness matrix was derived, which displacement field was same to the element shape. Then through the horizontal and vertical direction equilibrium equations were solved, the relationship between main cable shape and the system parameters was obtained. The calculation method was compiled to MATLAB 7.0 programs, and applied to ascertain the main cable-shaped of one long-span suspension bridge. When the paper calculated result was contrasted with the design value, it could be concluded that: the main cable-shaped of long-span suspension bridge could be accurately obtained by the paper method, and the method was convenient for compiling.
Feasibility Study of the Stability Evaluation of GT Propellant with Methyl Violet Test Burst Time
Authors: Chang Wen Ping , Lu Gui E , Jiang Jin Yong , Du Shi Guo , Liao Jing Lin
Published: November 2010

GT propellant with different storage life was obtained by aging test. The stabilizers (AkII and Res) content and methyl violet test burst time of the samples were measured by GC and methyl violet test instrument. The relationships of tb vs. ta, tb vs. R and R vs. ta were determined. The results show that the variation regularities of tb with ta and Res content with ta are very similar, and the variation regularity of tb with Res content is linear relationship. In addition, the Scattering field of methyl violet test burst times is very small. So, it is feasible that the stability evaluation of GT propellant with methyl-violet burst time.
Microwave Reflection Characteristics of the Fe/Al2O3 and Fe3Al/Al2O3 Composites
Authors: Wei Jian Qiang , Wang Jian Bo , Qiao Liang , Wang Tao , Li Fa Shen
Published: November 2010

Fe/Al2O3 and Fe3Al/Al2O3 composites were prepared by mechanochemical synthesis. Microwave characteristics were measured in 0.1–18 GHz. A reflection loss (RL) exceeding -10 dB in the frequency range of 1.5-8.5 GHz for an absorber of 6-1.5 mm was achieved for the Fe3Al/Al2O3 composites. Optimal RL of -41 dB was obtained at 2.8 GHz for an absorber thickness of 3.9 mm. The good microwave-absorption properties results from a proper impedance match as a consequence of the insulator Al2O3 around Fe and Fe3Al. Microwave reflection results show that the corresponding frequency and the matching thickness is closely related to the quarter wavelength matching condition and these composites can be attractive candidates for electromagnetic wave absorption materials.
Development of a New Thermal Insulating Concrete Block by Spent Polystyrene Foam
Authors: Cai Li Peng , Yun Ying Wei , Jang Ii Young , Kim Seong Kyum
Published: November 2010

In this research, a new Thermal Insulating Concrete Block (TICB) is produced via “sandwich” structure by spent polystyrene foam, cement and other raw materials. According to the concerned China Standard Test Method for Building Material, the main properties of this TICB are measured successfully. By comparing its properties with those of autoclaved aerated concrete block as wall material, it can be concluded that comprehensive properties of this concrete block is better than those of autoclaved aerated concrete block. The extrusive advantage of producing this TICB is that large amount of spent polystyrene foam which is hard to be decomposed as industrial waste can be consumed. This is propitious to environmental protection and energy conservation. Therefore, TICB studied in this paper is one kind of green environmental wall material with bright prospect.
Finite Element Analysis of Pressure Influence on Densification of Titanium Alloy Powder under Hot Isostatic Pressing
Authors: Liu Guo Cheng , Shi Yu Sheng , Wei Qing Song , Wang Ji Wei
Published: November 2010

To investigate the influence of pressure on densification behavior of metal powder under hot isostatic pressing (HIP), the consolidation of Ti6Al4V powder at various applied pressures during HIP processes were investigated by finite element method in this paper. The plasticity and creep phenomenon of the compact under high temperature and pressure were described by the viscoplastic Perzyna model, which integrated with a modified yield criterion for porous metal materials. The thermo-mechanical coupling analysis was carried out by the finite element code MSC.Marc. The calculated results show non-uniform density distributions for the compact, but this phenomenon decreases as increasing the applied pressure. The densification rate is significantly influenced by applied pressure. The consolidation mechanisms for powder compact were also discussed.
Experimental Investigation on Mechanical Behaviors of Polymer Film Material
Authors: Wang Huai Wen , Li Qing , Shao Wen Quan , Miao Hui
Published: November 2010

The mechanical behaviors of Nylon6 polymer film material are investigated experimentally. A technique, marker identification method, for non-contact optical measurement of in-plane displacements based on correlation analysis is employed to measure the deformation of the film specimens. Based on the uniaxial tension experimental results, the stress-strain relationship is obtained, which result in Young’s modulus and the Poisson’s ratio. In the creep experiment, the time-depending response of polymer film material is studied. The strain state is determined by measuring the deformations over time. Based on the obtained data about the material’s response, the bulk-modulus K(t) is calculated based on BOLTZMANN’s superposition principle.
Failure Modes-Based Multi-Objective Optimization Design of Steel Reinforced Concrete Frame Structures
Authors: Zheng Shan Suo , Li Zhi Qiang , Wang Bin , Li Lei , Wang Wei
Published: November 2010

The frame structure designed with the existing design code in zones of high earthquake intensity doesn’t satisfy with the expectation of strong column–weak beam. Therefore, a new optimal approach based on failure modes with the ability to limit the cost and the damage is proposed. In the process of optimization design, all the stories of a building with the same interstory drift is defined to obtiain the minor damage, while the damage values of beams and columns are difined to obtain the except failure modes. At last a six-story steel reinforced concrete frame structure is designed to verify the method developed inhere. It is concluded that the method can supply an effective way to reduce both the damage and the cost of steel reinforced concrete frame structure, and can obtain the except failure modes.
Nonlinear Analysis of Steel Reinforced High Strength and High Performance Concrete Eccentric Columns
Authors: Zheng Shan Suo , Wang Wei , Wang Bin , Li Lei , Hu Yi
Published: November 2010

According to experiment of four steel reinforced high strength and high performance concrete(SRHSHPC) columns with different eccentricity, this paper establishes four equally parameter numerical models by finite element program ANSYS. The failure mechanism, failure mode and mechanical behaviors of the SRHSHPC columns with large and small eccentricity can be revealed by comparing the numerical simulation results with the corresponding experimental results. And the approximate plane-section assumption in SRHSHPC eccentric columns is verified by the study of the relationship between load and strain. It is shown that when constitutive models and failure criteria of SRHSHPC and steel are in precise case, the calculation results agree well with the corresponding experimental results.