bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring System Design of Fuse Automatic Assembly Machine Based on WinCC
Authors: Jiao Zhi Gang , Cui Han , Guo Qiu Ping
Published: August 2011

Structure and function of assembly machine were introduced on the background of engineering project-“research and development of fuse automatic assembly machine”. The control system was realized by protocol communication between S7-300 PLC as on-site control unit and industrial personal computer(IPC). The IPC monitoring system was developed by WinCC V6.0 configuration software and the work process of assembly machine,which includes real monitoring, voice alarm, operation permission setting, data archiving,etc.,was implemented by combining VB and C script. The assembly machine met production requirements by testing.
Design of Measurement and Control System for the Rail Fastening Spring Clip Type A and B
Authors: Yao Yu Peng , Shi Ying , Song Yong Ping
Published: August 2011

The measurement and control system is designed to control the measuring instrument which measures the geometric parameters of rail fastening spring clips. The structure and work principle of the measurement and control system are presented. Nine geometric parameters of a rail fastening spring clip which is installed only one time can be measured atomically. The limited errors of measured parameters are largely smaller than one tenth of the geometric parameter tolerance. It only spends 40 seconds to measure a rail fastening spring clip. It improves the quality of the rail fastening spring clip production and ensures that it is safe and reliably used in railway.
Experimental Determination of Aircraft Structural Material Life Envelope
Authors: Zhang Hai Wei , He Yu Ting , Wu Li Ming , Shao Qing , Du Jin Qiang
Published: August 2011

A new approach to reflect the relation of aircraft structural calendar life and fatigue life is established by pre-corrosion and fatigue test with 2A12 alloy specimens. The corrosion factor curve is fitted from the test, and then aircraft structural corrosion and fatigue interactive process during actual in-service environment is simulated. Furthermore, combining with Miner linear cumulative damage theory and the method of ‘calendar life tending to minimum’, life envelope is found. The result shows that flight strength is the key factor for aircraft structural life, and the envelope can be used to realize single aircraft structural life surveillance.
Numerical Analysis of Hydrodynamic Lubrication on Water-Lubricated Rubber Bearings
Authors: Wang You Qiang , Li Chao
Published: August 2011

Water lubricated rubber bearings are one of the most appropriate bearings for underwater use. The most popular design used widely today is the straight fluted rubber bearing. The special configuration leads to partial hydrodynamic lubrication and low load capacity. A new bearing bush structure which is favorable for constructing continuous hydrodynamic lubrication was designed and produced for experiment in the paper. The eccentricity ratio of the new structure rubber bearing was measured under different loads in experiment. Used the measured eccentricity ratios, the load capacity was calculated by numerical simulation and compared with the given test values. The calculated values were in good agreement with the given test results. The results show that complete hydrodynamic lubrication can be formed in the new designed rubber bearing. The experimental results also indicate that there is an appropriate bearing clearance which the load capacity is up to the maximum.
Study on Expression of SIF for Tapered Lug Subjected to Oblique Pin-Load
Authors: Wu Li Ming , He Yu Ting , Zhang Hai Wei , Cui Rong Hong , Du Jin Qiang
Published: August 2011

The finite element model of a symmetric tapered attachment lug is built by using the finite element software ANSYS, a cosine pin-bearing pressure distribution is applied on the surface of the pin-hole as a boundary condition. The stress intensity factor (SIF) expression for a single through-the-thickness crack in a symmetric attachment lug subjected to an oblique pin-load less than 45 degrees is determined by studying on the effect of the dimensionless crack length (a/R1)，the ratio of outer radius to inside radius (R2/R1), the inside radius (R1), the tapered angle (β) of lug and the load degree (α) on SIF value. The paper can be helpful in assessing and designing damage tolerant attachment lugs.
Study on Locally Resonant Phononic Crystals Based on Automotive Noise Control
Authors: He Yu Yang , Jin Xiao Xiong , Wei Huan
Published: August 2011

Automotive low frequency noise is difficult to control in a traditional way. Locally resonant phononic crystals (PCs) can forbid the propagation of certain frequency. This PCs’ structure also can be fabricated to apply in automotive noise control. The simulation method is applied to establish the model of two-dimensional (2D) locally resonant phononic crystals in order to research the impact of the parameters on the propagation. The band gap of locally resonant phononic crystals in z mode is calculated using the simplified model.
Simulation Analysis and Research of Tire Wear
Authors: He Jian Feng , Jin Xiao Xiong , Hou Chen Yuan
Published: August 2011

The theory of tire wear computation is researched, and steady state transfer analysis and steady state rolling slippage are analyzed and deduced; the uniform wear rate of discrete node on the tire tread pattern is induced based on adhesive wear mechanism. Tire body model and tread pattern model are established by using Neo-Hooken constitutive model and linear elastic model, and the whole tire model is formed. Tire wear simulation analysis is preceded with combination of Abaqus Arbitary Lagrangian and Eulerian (ALE) method and the user subroutine programmed according to tire wear computation model. Tire wear of different mileage under free rolling state, tire wear under breaking condition and driving condition are compared, and slip angle, load and tire pressure’s impact on tire wear are analyzed.
Aerosol Behavior in the near Wake Region of the Vehicle
Authors: He Zhu , Shen Qiao Zhen , Li Bao Kuan , Chan Tat Leung
Published: August 2011

In the present study, the interaction effects of different vehicle speeds and vehicular exhaust tailpipe exit velocity conditions on the exhaust particle dynamic behaviors in the near-wake region behind the studied vehicle were numerically investigated. The results showed that the particles were drawn up into the recirculation region and then moved toward into the upper vortex by its lower vortex. A lower particle number concentration behind the studied vehicle is observed for a higher vehicle speed because of the rapidly increasing dilution ratio and the nucleation rate. The particle volume concentration is the highest in the recirculation region behind the studied vehicle and is diluted gradually beyond the recirculation region in the downstream.
Stability Optimal Control Based on 15-Dof Vehicle Model
Authors: Fan Xiao Bin , Jiang Yu , Wang Hui Gang
Published: August 2011

The 15 degrees of nonlinear dynamic vehicle model is established, and then Dugoff and magic formula tire model are studied by comparison. Then the braking system dynamics model and the side-slip angle estimation algorithm are discussed. Stability control system is established based on the control target of combined yaw and side-slip angle with linear 2-dof vehicle handling characteristics model. It shows that control system can perfectly control vehicle driving and can improve the stability of car active safety through the serpent’s simulation test.
Research on Congestion Mitigation Strategy Downstream Off-Ramp for Urban Expressway Based on Fuzzy Logic Method
Authors: Chen Xue Wen
Published: August 2011

As the uncertain characteristics of traffic flow in urban expressway, fuzzy control can be used as an effectual way to solve traffic problem. A fuzzy controller of signal intersection is designed for alleviating traffic congestion downstream off-ramp at the Surface Street. The overtime of green-light and the next time for green-light phase are optimized according to the queue lengths and the numbers of phase delay, and the method corresponds to a man’s decision-making process. Simulation research based on MATLAB program design is carried out and the results show that the methods are promising and the fuzzy controller have a better performance for congestion mitigation downstream off-ramp of urban expressway.
Study on Bike Rental Pricing Model under the Low-Carbon Mode
Authors: Chen Xin , Zhang Yuan Yuan , Yu Jia Xun
Published: August 2011

Bike rental is an important traffic mode under the low-carbon mode. Bike rental pricing is the key technology of the bike rental. In the paper, bike rental pricing model is researched. Firstly, the influential factors of the bike rental pricing are analyzed, such as cost, demand, rental location, time, depreciation rates, government policy, competition conditions, income level, psychological pricing, the other public transport pricing situation and so on. Secondly, the average-cost pricing and the Logit model are combined, and the pricing model is established by considering the depreciation rate, the distribution rate, the ratio of the travel time and the rental time. Finally, the model is solved. According to time, rental location and bike models, the price of bike rental and the appropriate deposit of bike can be determined by using this model.
Study on the Relationship of Airbag Effect and Occupant Position
Authors: Wu Xiu Chunb , Li Kun , Wang Bo , Su Xue Shenc
Published: August 2011

Computer simulation method is used to study the relations of airbag effect and occupant position. By changing the position of 50% dummy model to achieve the purpose of changing the position between airbag and occupant, three kinds of simulation test are made, and the simulation results are analyzed and compared. It is shown that between the belted occupant and airbag exists such a position or distance, at which the injury to occupant is the smallest when the traffic accident happens.
Natural Frequency Study of Automotive Engine Valve Spring by Experimental Method
Authors: Liu Hao , He Hui
Published: August 2011

This paper presents a frequency response function method to measure the natural frequency of automotive engine valve springs with respect to different spring height. A new apparatus is developed for changing the spring height within the range of valve lift. The test results indicate that the natural frequency changing highly depends on the different pitch type of the spring. The measured natural frequencies of valve spring can be direct applied to the estimation of valve spring surge characteristics.
Design and Controlling Study on Electro-Hydraulic Mix-Drive Cooling System in Vehicle
Authors: Duan Min , Liu Yang , Wang Dong
Published: August 2011

This thesis analysis the work course of the system, the match of major part, a fuzzy method for controlling the engine coolant temperature is proposed. The fuzzy rule base is correspondingly established based on the experimental data. The control query table is created through computing and analyzing via the fuzzy logic tools in MATLAB. The test indicates that only a little improvement of the current engine cooling system can better solve the problem that it is difficult to accurately control the engine coolant temperature.
Jackknife Control on Tractor Semi-Trailer during Emergency Braking
Authors: Zhou Shu Wen , Zhang Si Qi , Zhao Guang Yao
Published: August 2011

Emergency braking on a low coefficient of friction or split-mu road surface, the semi-trailer may push the tractor from behind until it spins round and faces backwards, and a jackknife accident occurs. In this paper, the tractor semi-trailer kinematics was analyzed and a 3-dof of tractor semi-trailer model was used to design a state observer to estimate the articulation angle. To avoid a jackknife, the four-channel ABS which can produce maximum braking force will be switch to three-channel ABS according the estimated articulation angle. The virtual prototyping simulation results show that the jackknife control system can improve the tractor semi-trailer lateral stability under emergency braking and shorten the stop distance dramatically on split-mu road surface at high speed.
Engine Fault Diagnosis Based on PSO-BP Network
Authors: Nie Li Xin , Zhang Tian Xia , Wang Shu Ju , Zhang Li Ping
Published: August 2011

BP network could deal with some nonlinear problems such as fault diagnosis, but the gradient-based method tends to get stuck in local optima or premature convergence. As a population-based heuristic optimization algorithm, PSO method could increase training accuracy of BP network so as to improve discriminant precision of fault diagnosis of equipment such as engine. Ladder diminishing inertia weights tend to improve network’s convergence precision and efficiency during the late stage of PSO iterations, in addition, LPSO or RegPSO contributes to confining premature convergence. The PSO-BP fault diagnosis model of 190A diesel engine has verified the above opinions.
Research on Outlier Mining Algorithm Oriented to Traffic Information
Authors: Xie Wen Ge , Wang Hai Hong , Gu Xin Cai , Guo Yan Feng
Published: August 2011

This paper designs a new outlier mining algorithm based on distance through introducing the "key attribute", which reduces the amount of data mining and increases the efficiency of outlier mining, simultaneously, improves the common distance measure and calculates with the improved Modifing Weighted Manhattan Distance(MWMD), the improved mining algorithm cancels the requirements of the parameter setting in the case of without affecting the mining results and gives the isolation degree of outliers.
Component of Cu/n-SiO2 Composite Particles by Mechanical Milling
Authors: Du Jian Hua , Zheng Xiao Hui , Zhu Xiao Ying
Published: August 2011

Copper based composite powders with nano-SiO2 were prepared by mechanical milling technology. The effects of milling time on morphology and component of the composite particles were characterized by scanning electron microscopy (SEM) and energy disperse X-ray spectroscopy (EDS), respectively. Results showed that dendrite composite particles change to the flaky, and then to spherical ones with the milling time increasing. The n-SiO2 particles disperse more homogeneously in the composite particles with the milling time increasing.
Research on Synchronous Testing Technique of the Shock Absorber Performance in Automotive Coaxial Suspension
Authors: Wang Tian Li , Sun Xiao Bang , Yu Yang
Published: August 2011

According to the test specifications of Bench test methods of automotive telescopic shock absorber（QC/T545-1999）, through controlling variable frequency motor which drives crank-link-slider mechanism，harmonic excitation is acted on shock absorbers. Meanwhile, signals of two force sensors and displacement sensor are acquired. The synchronous performance test of single condition and multi-work condition is achieved for shock absorbers in automotive coaxial suspension. The velocity characteristic and resistance-displacement characteristic are tested in specified range of the velocity of motor.
Single Discharge of Dry µ-EDM on Silicon: Crater and Plasma Temperature Measurement
Authors: Kanmani Subbu S. , Ramkumar Janakarajan , Dhamodaran S.
Published: August 2011

To improve the performance of the Electric discharge machining (EDM) process it is of interest to characterize the plasma involved. Plasma temperature needs to be measured as an initial phase of plasma characterization. Non-contact optical emission spectroscopy has been used to measure the plasma temperature. The plasma temperature and crater morphology has been investigated for different energy conditions on Silicon in dry µ-EDM condition. The plasma temperature is calculated using line pair method and crater morphology analyzed by scanning electron microscope (SEM) and profilometer.
Calculation of Statistical Values of Phase Interface Valence Electron Structure Parameters of Cu-Zn Alloy
Authors: Li Fei , Zhao Xia
Published: August 2011

Based on the average atom model, the statistical values of valence electron structure (VES) parameters Δρ′, σ of homophase interface and heterpphase interface had been calculated in Cu-Zn alloy. VES parameters can characterize properties of interface bonding. The effect of Zn in the Cu matrix on the interface strengthening was discussed by the Δρ′ and σ. The calculation results showed that Δρ′ and σ values of homophase interface and heterophase interface of alloy phase were bigger than ones of Cu matrix. It was the essence of interface strenghening. The heterophase interface value σ was smaller compared with the homophase interface value σ under different Zn contents (weight percent). It was the reason that the stability of matrix was superior to that of between matrix and solid solution.
Effect of Process on Microstructure and Elevated Temperature Mechanical Behavior of Multi-Phase NiAl-Fe(Nb) Alloy
Authors: Han Ping , Guo Jian Ting
Published: August 2011

The microstructure and elevated temperature mechanical behavior of as-cast, HIPed and directionally solidified NiAl-Fe(Nb) Alloys have been investigated. The results show that the microstructure of as-cast NiAl-Fe(Nb) alloy consists of dendritic regions (b) and interdendritic regions (g/g¢) with non-continuous NbNiAl(Laves) phase segregating at the interfaces of b and g/g¢ phases. The HIP processing does not alter the microstructure of as-cast alloy. The longitudinal dendritic microstructure of the DS NiAl-Fe(Nb) alloy is regular. Room temperature elongations of as-cast and HIPed NiAl-Fe(Nb) alloys are all zero, however, 0.4% for the DS alloy. The strength and elongation of the HIPed alloy are higher than that of as-cast alloy. The yield strength and ultimate strength of the DS alloy are equivalent to that of as-cast alloy, but elongation of the DS alloy is higher than that of as-cast alloy, the elongation exceed 100% at 1273K, which indicates that the DS alloy can be deformed superplastically.
Microstructure and High Temperature Mechanical Property of Directionally Solidified NiAl-Cr(Mo)-W/Nb Alloy
Authors: Qi Yi Hui , Ma Sheng Nan , Guo Jian Ting
Published: August 2011

The microstructure, high temperature tensile behavior of the DS NiAl-Cr(Mo)-W/Nb alloy have been investigated. The transverse microstructure of the alloy consists typically of eutectic colonies of NiAl and Cr(Mo) phase with white phases segregating at the cell boundaries. The white phase is possibly Cr(Mo) phase containing large amount of Nb and W elements. The longtitudinal microstructure of the alloy is lamellar with the direction basically parallel to the directional solidification direction. The tensile yield strength and ultimate strength of the DS NiAl-Cr(Mo)-W/Nb alloy are much higher than that of the general cast NiAl-Cr(Mo)-W/Nb alloy, and the elongation of the alloy is also higher than that of the general cast alloy. The fracture is debonding along phase boundary and cleavage.
Study on Photocatalytic Performance of F-Doped Nanometer TiO2
Authors: Yan Shao Feng , Sun Tong
Published: August 2011

F-doped TiO2 by hydrothermal synthesis method is prepared in this paper. By basis of sunlight and porous nickels as the carriers, the samples were characterized by Transmission electron microscopy (TEM), scanning electron microscopy (SEM), infra-red (FT-IR) and diffuse reflectance spectroscopy (UV-vis). The photocatalytic performances of the samples were estimated by degrading Rhodamine B. which indicates that the reaction of photocatalytic degradation of Rhodamine B follows the zero order kinetic law. The photocatalytic performances are increased by F-doped. And F optimum doping dosage is 2.0%. After calcination at 500°C, the photocatalytic performance of the sample has not been obvious improved.
Effect of Temperature and Grain Size on the Corrosion Behavior of 316L Stainless Steel in Seawater
Authors: Xin Sen Sen , Xu Jian , Lang Feng Jun , Li Mou Cheng
Published: August 2011

The corrosion behavior of 316L stainless steel was investigated in seawater at different temperature by using cyclic anodic polarization. The results indicated that two 316L specimens with different grain size showed similar pitting potential at 25°C. The increase of seawater temperature led to the linear decrease of pitting potential and repassivation potential. Because the pitting resistance of fine grain steel reduced larger than that of coarse grain steel with increasing temperature, the latter had a higher pitting potential about 60 mV at 85°C. Compared with the coarse grain steel, the fine grain steel showed a longer induction time for pitting at 65°C.
Electrochemical Corrosion Behavior of Laser Gas Nitrided Layer on the NiTi Shape Memory Alloy in Hank’s Solution
Authors: Zhang Song , Tang Hu Jiao , Hu Fang , Zhang Chun Hua , Man Hau Chung , Zhang Qiao Qian
Published: August 2011

A nitrided layer was formed on the NiTi shape memory alloy (SMA) after being irradiated by a continuous wave Nd-YAG laser in a N2 environment. With optimum process parameters, a compact laser modified gradient layer reinforced with fine TiN particles was achieved. Electrochemical measurements of the laser gas nitrided layer on the NiTi SMA showed that the corrosion potential and the breakdown potential were increased while the corrosion current was decreased as compared with the untreated the NiTi SMA. The polarization resistance of the laser gas nitrided layer on the NiTi SMA was increased significantly while the capacitance was decreased. Based on the EIS spectra, a simple model and an equivalent circuit were proposed to describe the electrode-electrolyte interfaces.
Microstructure and Hot Corrosion Properties of Laser Cladding of a Co-Base Alloy on the Leaf Surface of Gas Turbine
Authors: Zhang Song , Zhou Gong You , Hu Fang , Zhang Chun Hua , Wang Mao Cai , Zhang Qiao Qian
Published: August 2011

The temperatures inside the gas turbine reach up to 1000°C, alloys used for gas turbine components must be oxidation, and corrosion resistant, and stable in structure under high temperature circumstances. A Co-based alloy was cladded on the 1Cr18Ni9Ti stainless steel surface using a high power carbon dioxide laser. The microstructure evolution and hot corrosion properties of samples in 75%Na2SO4+25%NaCl saline were investigated. The results show that the microstructures of the cladded layer is fine, and the hot corrosion resistance of the cladded layer was significantly improved because of the formation of a protective oxide film of CoO and CoO•Cr2O3. Under high temperature corrosive atmosphere, the high content of Co promoted the formation of the protective oxide film. The refinement of dendritic structures and the formation of Co-based alloy oxides lower the penetration rate of the sulphur ions that induce the intergranular corrosion.
Study on Wear and Corrosion Properties of Ti6Al4V Alloy by Laser Gas Nitriding
Authors: Zhang Chun Hua , Tang Li Wen , Hu Fang , Zhang Song , Man Hau Chung
Published: August 2011

Titanium alloys have successfully been used as surgical implants. Laser gas nitriding (LGN) is an effective method to improve the wear and corrosion resistance of titanium alloys. A nitride strengthened uniform layer, free of cracks, was obtained on the Ti6Al4V alloy by irradiating with a continuous wave Nd-YAG laser in a N2environment. The microstructure, electrochemical corrosion and tribological behavior of the alloy before and after LGN were studied by SEM, XRD, potentiostat, microhardness tester and tribometer. The results show that the performance and composition of the surface of the Ti6Al4V alloy were significantly improved by LGN, with better corrosion resistance in simulated body fluid and better wear resistance.
Evaluation of the Friction and Wear Properties of PEI Composites Filled with Glass and Carbon Fiber
Authors: Cai Chi Lan
Published: August 2011

PEI composites filled with glass and carbon fiber was synthesized. The aim of the research article is to study the mechanical and two-body abrasive wear behaviour of glass/carbon fiber reinforced PEI composites. The microstructure of the composite was examined by scanning electron microscopy. The results showed that the highest specific wear rate was for glass fiber reinforced PEI composite was higher than that of carbon fiber reinforced PEI composite.
Anticorrosion Conversion Coating Content Lanthanum and Phosphate on Foam Mg Alloy
Authors: Niu Li Yuan , Shi Zi Mu , Lin Ji Jing , Li Yong , Xu Lin Chao , Zhao Lan
Published: August 2011

Foam magnesium alloy was an idea substitute of hard tissue of human bodies because its elasticity module was close to the bone of human. In the paper, foam degradable magnesium alloys were prepared by “Press-Dissolution-Vacuum sintering-Hot treatment-Aging” powder manufacturing process firstly. Then samples were coated by immersion in a bath containing phosphate and rare earths lanthanum. Results show that, Mg-0.9Mn foam magnesium alloys after hot treatment had better anticorrosion performance; and coated foam magnesium alloys form the bath with phosphate lanthanum chloride had lower rate of degradation.
Al-0.90%Fe Alloy Sectional Solidified in a Gradient Magnetic Field
Authors: Zhang Jian Feng , Ba Qi Xian , Cui Jian Zhong
Published: August 2011

The effect of DC gradient magnetic field and the sectional solidification on the structure of Al-Fe hypoeutectic alloy was investigated. The experiment results showed that the morphology and structure of the sample were homogenous, when it was bulk solidified without magnetic field. When the sample was sectionally solidified without magnetic field, the upper part had less iron content, bigger dendritic trunk and less interdendritic precipitate. When the sample was sectionally solidified in the gradient magnetic field, the above-mentioned differences between the upper and lower part were more prominent. The physical essence of the experiments was analyzed with quantum mechanics and solidification theory.
Influences of Acting Parameters of Electric Pulse Modification on the Al-22%Si-1.5%Cu Alloy
Authors: He Li Jia , Wang Jian Zhong , Qi Jin Gang , Du Hui Ling , Liu Xing Jiang , Wang Bing
Published: August 2011

Hypereutectic Al-Si alloy are desirable and promising for many structural applications. The influences of electric pulse parameters on Al-22%Si-1.5%Cu alloy by using OM (optical microscope) analysis along with wear test had been investigated. This work focused on studying the comparison of its solidification structure and wear resistance property with and without electric pulse treatment, respectively. The results indicated that EPM (electric pulse modification) treatment with different voltage parameters along with the frequency parameters both had the remarkable effects on micro-structure, and the grain size of alloy was refined gradually with the increase of pulse voltage or frequency. The wear resistance property of the alloy was enhanced by electric pulse treatment. It was observed from DSC cooling curve that the precipitation peak point of primary silicon was delayed by electric pulse modification comparing to the original sample without electric pulse treatment, which was analyzed to play a critical key in the alloy grain refinement.
Microstructure and Micromechanical Property of C/C-SiC Composites
Authors: Cui Y. Y. , Bai Rui Cheng , Li A. J. , Ren M. S. , Sun J. L.
Published: August 2011

The C/C-SiC composites are prepared by the reaction molten infiltration process of silicon powders, using porous C/C composites as preform. C/C composite frameworks with various bulk densities are prepared by the chemical vapor infiltration (CVI) combined with the resin impregnation-pyrolysis methods, using needled-carbon fiber felts as preform. Characterization of the microstructure was conducted with a digital microscope (VHX-500) and a polarized light microscopy, respectively. The hardness (H) and the elastic modulus (E) of the composites are measured using a nano indentor. The results show that the indentation behaviors of the pyrolytic carbon and resin carbon are elastic while silicon and silicon carbide show a plastic deformation behavior. The hardness of the resin carbon as well as the pyrolytic carbon is 2.1GPa and 1.3~1.6GPa, respectively. E of SiC varied from 360 to 259GPa and H from 36 to 21GPa. For Si, the value of E and H are 155-170GPa and 11.7GPa, respectively. The relationship between microstructure and mechanical properties of C/C-SiC composites were analyzed.
Application on Statistical Value of Phase Structure Formation Factor to Fe-C Phase Diagram
Authors: Xue Wei Hua , Ren Xin , Gao Zhi Yu , Shi Hai Fang
Published: August 2011

Based on the empirical electron theory in solids and molecules (EET), the statistical value of phase structure formation factor (S') was calculated by using the calculation methods of statistical value of alloying valence electron structure parameters. The effects of alloying elements upon austenitic zone of Fe-C phase diagram were discussed. The results show that: 1) Mn and Ni can increase the S' value of γ-Fe and austenitic phase, which increase their stability, leading to expand the γ-zone; 2) Cr, Mo and Si can increase the S' value of ferrite and cementite, which make them easier to precipitate, leading to reduce γ-zone. The research results agree well with real situations.
Effects of Elastic Modulus Degradation on Simulation of Stretch-Bend Springback of Dual Phase Steel
Authors: Lu Chao , Kang Yong Lin , Zhu Guo Ming , Liu Ren Dong , Lin Li
Published: August 2011

The stretch-bend springback of dual phase steel DP590 was studied experimentally and numerically in this paper. The aim of this work is to investigate the effects of elastic modulus degradation on springback prediction. Two anisotropic yield function yld89 and yld2000 were utilized along with isotropic hardening law. The appropriate material parameters characterizing the elastic modulus decrease were identified by response surface modeling. The current work showed that the accuracy of springback simulation improved when considering elastic modulus decreased with plastic strain and yld2000 can predict springback more accurately considering blank orientation in stretch bending.
Influence of Sn Content on the Microstructure and Dry Sliding Wear Behaviour of Hypereutectic Al-20Si Alloy
Authors: Wu X. F. , Zhang G.A.
Published: August 2011

The influence of Sn content on the microstructure and dry sliding wear behaviour of hypereutectic Al-20Si alloy was investigated. The results show that the b-Sn in the alloys precipitates mainly in the form of strips and blocks on the grain boundaries of α-Al phase or the interface of silicon and α-Al phases. The addition of Sn can improve the wear resistance of the hypereutectic Al-20Si alloy.
In Situ Observation of Solidification Behavior in a Q235 Steel by Using Electric Pulse Modification
Authors: Dai Shan , Qi Jin Gang , Zhao Zuo Fu , Wang Jian Zhong
Published: August 2011

In the unmodified and EP-modified melt of Q235 steel, the solidification behavior including the nucleation and growth of crystals has been observedin situby use of a confocal scanning laser microscope combined with an infrared image furnace, and meanwhile, described the characteristic of phase transformation. The result shows that the every stage of phase transformation is advanced; the phase transformation time is shortened, and temperature is reduced during heating proceeds. On the other hand, it can be observed that the nucleation density of solid phase increases and has an even distribution among the liquid phase.
Study on Inclusions in Ductile Cast Iron
Authors: Guo Wen Tao , Chang Guo Wei , Chen Shu Ying , Wang Ji Chao
Published: August 2011

The type, shape and distribution of inclusions in ductile cast iron were studied using a scanning electron microscopy (SEM) and the energy spectrum analysis, combining the thermodynamic calculation of inclusions formation. The results show that the oxides are most likely formed from the thermodynamics in ductile cast iron when the temperature is 1373~1873 K , followed by the sulfides, the carbides again. There exist the uniphase inclusions MgO, SiO2and MgS, the heterogeneous inclusions of containing rare-earth MnO-MgO-SiO2-La2O3and MgS-LaS-SiO2-Al2O3-MgO , and the heterogeneous inclusions of non-rare earth SiO2-MnO-MgO-Al2O3in ductile cast iron. The shapes of the inclusions are mainly polygon, and the size variation is from 3 to 10 um. The inclusions are mainly distributed on the graphite ball surfaces, the ferrite grain boundaries and in the pearlites.
A New Wind Vibration Control Strategy Based on Active Variable Stiffness
Authors: Dong Jin Kun , Wang Xue Zhi , Sun Hong Jun
Published: August 2011

Based on the active variable stiffness, a new semi-active control method, whose principal content is using frequency control (FC), is presented. As a new semi-active algorithm, short time maximum entropy analysis is firstly proposed and the exact time and frequency signal at every control short time sequence also is given. The calculation results of a case of a 40-story building showed that the FC method is more effective than the results calculated by the method in the current structural design of tall buildings. The robustness of the algorithm is obtained and the displacement of the structure is reduced effectively.
Microstructure and Deformation Characteristics of X80 High Deformability Pipeline Steel
Authors: Meng De Liang , Kang Yong Lin , An Shou Yong , Xia Dian Xiu
Published: August 2011

Two kinds of X80 high deformability pipeline steels have been processed by applying two-stage cooling process (TSC) and heat treatment on-line process (HOP). The microstructure of TSC steel and HOP steel are polygonal ferrite (PF) + quasi-polygonal ferrite (QF) + granular bainite (GB) multiphase and QF + GB+ martensite-austenite (M/A) multiphase respectively. In HOP steel, the volume of M/A is much more and the size is much larger than that in TSC steel. Some degenerated M/A constituents are also observed in HOP steel. The HOP steel has shown higher tensile strength, lower yield ratio and lower uniform elongation than TSC steel. The strain-nI (instantaneous n-value) curve of HOP steel could be divided into two stages and the TSC’s could be separated to three stages.
Corrosion Protection and Composition of Galvanized Steel Substrates by Bis-[3-(triethoxysilyl)-Propyl]Tetrasulfide and Gamma-Aminopropyltriethoxysilane
Authors: Shan Feng Jun , Qi Guo Chao , Liu Chang Sheng
Published: August 2011

Compound silane films were prepared on galvanized steel by immersing method using mixture of bis-[3-(triethoxysilyl)propyl]tetrasulfide and γ-aminopropyltriethoxysilane. The corrosion resistance of galvanized steel substrates was compared after treatment with bis-[3-(triethoxysilyl)propyl]tetrasulfide, γ-aminopropyltriethoxysilane and their mixture in 3.5%NaCl solution by potentiodynamic polarization and electrochemical impedance spectroscopy. The results indicated that corrosion current density of the mixed silane films was reduced evidently and self-corrosion pressure of that was shifted to left markedly and total impedance value of that increased about two orders of magnitude. The analytical characterisation was performed by Fourier transform infrared spectroscopy and atomic force microscopy. The results showed that bis-[3-(triethoxysilyl)propyl]tetrasulfide and γ-aminopropyltriethoxysilane were all connected with the former of films.
The Effect of Temperature and Pulling Rate on Young's Modulus of Steel FAS390Q
Authors: Liu Bing Yu , Yu Jing Yuan
Published: August 2011

The effect of heating temperature and pulling rate on Young's modulus of steel FAS390Q was studied. The results show that the relationship between Young's modulus and reciprocal of absolute temperature follows exponent change, and Young's modulus and pulling rate follows power function relation (power index for 0.189). Crystal vacancy is one of the most important reasons for elasticity phenomenon of steels, which results in the fact that the Young's modulus is affected by pulling rate. Based on the statistical analysis, the mathematical model between Young's modulus of high temperature and pulling rate is established.
Corrosion and Protection Studies of N80 Steel in CO2 Solution
Authors: Huang Xian Qiu , Zheng Jia Shen , He Rui , Liu Jian Rong , Bai Hui Ping , Tu Yuan Qiang
Published: August 2011

Corrosion inhibitor I9602 was synthesized in the laboratory. Infrared spectrum (IR) and ultraviolet spectrum (UV) in conjunction with nuclear magnetic resonance (NMR) had been performed to characterize its structure. Corrosion behavior of N80 steel and inhibition property of I9602 in pH=2 solution including 3% NaCl with carbon dioxide saturated were studied. The results showed that, the corrosion of N80 steel in this solution was quite serious, its corrosion rate was 43.02mm/a. The inhibitor synthesized I9602 was mainly composed of amide and imidazoline. When its concentration in above solution was 150mg/l, the inhibition efficiency of I9602 was 90%, and it had good inhibition effect. Using inhibitor was an economical protective measure.
In Situ Observation of Growth Process of δ Phase of 0.15% C Carbon Steel during Solidification
Authors: Yue Xu Dong , Jin Guang Can , Chen Shu Ying , Chang Guo Wei
Published: August 2011

In situ observation of growth process of high temperature phase in 0.15% C carbon steel during solidification concerned with using Confocal Scanning Laser Microscope (CSLM), the growth rate of -phase has been measured. The results indicate that high temperature -phase grows at cell crystal way when the cooling speed reaches 2°C/min in 0.15% C carbon steel. The -phase of round or oval cross-sectional shaped may grow stably. The growth rate of -phase is gradually getting slow along with increasing of curvature radius. The variation of growth speed tends to be similar with different solid-liquid interface shapes of -phase. The growth rate of concave solid-liquid interface is faster than that of convex solid-liquid interface for phase. The smaller radius of curvature of phase is, the faster the growth rate reaches.
Microstructure Evolution of Cold Rolled Hot Dip Galvanized Dual-Phase Steel during Continuous Heating Process
Authors: Jin Guang Can , Yue Xu Dong , Zhao Mei , Chen Shu Ying , Li Qing Chun , Chang Guo Wei , Zhao Ai Min
Published: August 2011

The annealing process of 800MPa grade hot dip galvanized DP steel was simulated on Gleeble-1500 thermo-mechanical simulator. The recovery and recrystallization of ferrite and the formation of austenite during the continuous heating process were studied in this paper. The results show that the fine equiaxed recrystallized nucleus started emerging nearby grain boundaries of deformed ferrites when the heating temperature was 630°C. With the increase of temperature, the recrystallized grain began to grow up, some new crystallized nucleus formed in other places with high stored energy of deformation. when the heating temperature was 690°C, the recrystallization process was basically finished, the deformed microstructure had been replaced by equiaxed ferrite grains. When the heating temperature was 730°C, the austenite nucleated on the carbide particles of the ferrite grain boundaries in the original pearlite area mainly. Some austenite also nucleated on the ferrite grain boundaries or the carbide particles within the ferrite grain. When the temperature was 750°C, the austenite began to grow along and parallel to ferrite grain boundaries.
Experimental Investigation of Formability Enhancement Using Hydraulic Counter Pressure Assisted Warm Deep Drawing
Authors: Kulkarni Sumedh , Akhtar Syed Nadeem , Ramkumar Janakarajan
Published: August 2011

Deep drawing processes are widely utilized in mechanical industries for producing several typologies of products ranging from computer industry to automotive components, from house products to furniture products. The goal of this study is to verify experimentally the warm deep drawing process assisted with hydraulic counter pressure as a suitable alternative to conventional deep drawing as a means for producing defect-free sheet metal parts. Using specific process parameters like blank holding pressure, blank diameter and temperature, wrinkle-free parts with deeper draws could be produced. An enhancement in LDR from 2.06 in conventional deep drawing to 2.16 in warm deep drawing with a lower blank holding pressure is achieved. The lower blank holding pressure leads to lesser thickness variation in the product this reducing the occurrence of fracture at the punch radius. The hydraulic counter pressure helps in reduction of wrinkles and enhancement of formability. The improvement in the LDR was observed around 200°C for warm deep drawing. This process reduces the forming restrictions of many materials, can produce complicated shapes and reduces the costs of material and die.
Deformation Behaviour of AZ31 Magnesium Alloy Sheets Produced by Twin-Roll Casting and Sequential Hot Rolling
Authors: Yu Yan Dong , Jiang Peng , Li Chao , Lin Kai
Published: August 2011

AZ31 alloy sheets were produced by twin-roll casting (TRC) and sequential hot rolling. Uniaxial tensile tests were used to evaluate the deformation properties of the AZ31 alloy at a strain rate of 7×10-4s-1 and a temperature range from room temperature to 400°C. The microstructure evolution and fracture behaviour were observed by optical microscopy and scanning electronic microscope. The results show that the elongation of the AZ31 alloy increases with increasing temperature at a strain rate of 7×10-4s-1. The AZ31 alloy begins to exhibit superplasticity at 300°C. The elongation of 497.8% is achieved at 400°C. The deformation of the AZ31 alloy at low temperature is controlled by dislocation motion, and with increasing temperature (above 300°C), grain boundary sliding (GBS) begins to play a dominant role during superplastic deformation.
Effects of Al Addition on the Microstructure of Fe-Mn-Si Ultra-Fine Grain Steel Welded Heat Affected Zone
Authors: Qi Jin Gang , Zhang Dong Jun , Zhao Zuo Fu , Dai Shan , Liu Xiao Chen
Published: August 2011

In order to improve toughness of the weld heat affected zone (HAZ) of ultra-fine grained (UFG) steel, a thermal simulation procedure of Fe-Mn-Si UFG steels with different Al addition was conducted and the corresponding microstructure was characterized and investigated. The results indicate that the maximum value on driving force of nucleation is ultra-fine grain steel with wtAl=0.6%, it has been explained in Nucleation kinetics that the grains are fine in UFG2. On the other hand, the bainite ferrite growth orientation has been increased. The toughness was remarkably enhanced in the steel welded heat affected zone. The formation of strie retained austenite and grain refinement of bainite ferrite in Fe-Mn-Si UFG steels with Al additions results in the increasing toughness of weld HAZ.
Study on Distribution of TiC Particles in Molten Steel under Electromagnetic Stirring Condition
Authors: Bin Shi Bo , Xing Shu Ming , Bao Pei Wei
Published: August 2011

This paper explored the distribution regularities of TiC particles in molten steel under electromagnetic stirring condition. The influencing factors on distribution such as the unit stirring power(P), the styles of TiC particles addition and the methods of surface pretreatment had been studied in our experiments. The results show that it’s easier to get uniform distribution by the way of high-power smelting with miniwatt stirring and the bottom injection. Besides, the pretreatment plays an important role in particles distribution.
Influences of Melt Temperature on Casting Structure of Al-Cu-Mn Alloy Treated by Electric Pulse Modification
Authors: Wang Bing , Tang Li Dan , Wang Jian Zhong , Qi Jin Gang
Published: August 2011

It was investigated that the effect of electric pulse modification (EPM) on the hot tearing of Al-5%Cu-0.8%Mn alloy. The results indicate that hot tearing tendency of all samples can be reduced treated by electric pulse with different parameters, moreover, hot tearing stress of alloy with EPM was enhanced 3 times or so than that of samples without treatment. Decreasing the quantity of eutectic in grain boundaries, decreasing the end-solidifying temperature of the alloys, and refining the grains are main causations for increasing hot tearing resistance of Al-5%Cu-0.8%Mn alloy by electric pulse modification.
Bulk and (001) Surface Properties of TiAl3 Compound
Authors: Wang Li , Gong Jian Hong , Gao Jun
Published: August 2011

The structural and electronic properties of bulk and (001) surface of TiAl3 have been examined by the first-principles total-energy pseudopotential method based on density functional theory. The lattice constants and heat of formation of bulk TiAl3 we obtained are in good agreement with the experimental and other theoretical values. The calculated bulk properties indicates that bonding nature in TiAl3 is a combination of metallic and ionic, in which the metallic bonding become the predominate one. the strongest hybridization exist in the DO22 structure, the Al-3p and Ti-3d bonding of TiAl3 play the dominant role in hybridization. The structural relaxation and surface energy for (001) slab have been simulated to make sure the stability of slabs with different atomic layers. Compared to TiB2 (0001) slab, TiAl3 surfaces shows smaller structural relaxation and lower surface energy, furthermore, the charge redistribution of (001) slab shows almost the same characteristics as bulk TiAl3, which confirms structural stability of TiAl3 with (001) slab. This present work makes a beneficial attempt at exploring TiAl3 surface as an ab initio method for studying possible nucleation mechanism of Aluminum on it.
Research on Stress-Strain Relationship Model of Concrete Prism Confined by GFRP
Authors: Jiao Xue Ying
Published: August 2011

Study the properties of GFRP confining concrete column through eight groups columns subjected to axial loading, and receive the stress-strain curves; various design parameters, such as amounts of GFRP sheets, width of straps and spacing of straps, have been considered. The results are: The axial compressive strength and ductility of concrete prism wrapped by GFRP sheets or GFRP straps have all increased to a certain degree, the process of destruction of concrete prism wrapped by GFRP become slower than common concrete prism. Based on the test results, deducing and validating the stress-strain relationship model of GFRP confining concrete prism.
Corrosion Behavior of Zr53.5Cu26.5Ni5Al12Ag3 Bulk Amorphous Alloy in 3.5% NaCl Solution
Authors: Li Yun , Shang Shi Zhi , Cheng Ming , Xu Liang , Zhang Shi Hong
Published: August 2011

The corrosion behavior of Zr53.5Cu26.5Ni5Al12Ag3 bulk amorphous alloy in 3.5% NaCl solution was investigated by using potentiodynamic polarization experiments and electrochemical impedance spectroscopy (EIS). The results show that Zr53.5Cu26.5Ni5Al12Ag3 bulk amorphous alloy has the better corrosion resistance than its corresponding crystal alloy. During the bath in the 3.5% NaCl solution at 25°C, Zr53.5Cu26.5Ni5Al12Ag3 alloy has the lower corrosion current density than the corresponding crystal alloy. After 100h, the corrosion current densities of Zr53.5Cu26.5Ni5Al12Ag3 and the corresponding crystal alloy are 3.8415×10-8A/cm2 and 5.2827×10-7A/cm2, respectively. The results of EIS test indicate that Zr53.5Cu26.5Ni5Al12Ag3 bulk amorphous alloy has the excellent corrosion resistance because passive film with stable structure formed on the surface in 3.5% NaCl solution. With an increase in the immersion time, the passive film becomes thicker. It leads to impedance resistance and corrosion resistance decrease. The surface of Zr53.5Cu26.5Ni5Al12Ag3 bulk amorphous alloy in 3.5% NaCl solution for 100h was analyzed by SEM and EDS. The results show that the corrosive pitting can be found at both the amorphous alloy and the corresponding crystal alloy. However, the amorphous alloy has the better corrosive pitting resistance than the crystal one because the corrosion products formed by selective dissolving of Zr and Al elements. Moreover, the addition of Ag element helps to improve the corrosion resistance of the amorphous alloy greatly.