bluuebunny/crossref_metadata_2025 huggingface dataset:
The Structure and Magnetic Properties of NiZn-Ferrite Films Deposited by Magnetron Sputtering at Room Temperature
Authors: Nie Shuang Jun , Geng Hao , Wang Jun Bao , Wang Lai Sen , Wang Zhen Wei , Xu Rui , Yue Guang Hui , Chen Yuan Zhi , Peng Dong Liang
Published: May 2013

NiZn-ferrite thin films were deposited onto silicon and glass substrates by radio frequency magnetron sputtering at room temperature. The effects of the relative oxygen flow ratio on the structure and magnetic properties of the thin films were investigated. The study results reveal that the films deposited under higher relative oxygen flow ratio show a better crystallinity. Static magnetic measurement results indicated that the saturation magnetization of the films was greatly affected by the crystallinity, grain dimension, and cation distribution in the NiZn-ferrite films. The NiZn-ferrite thin films with a maximum saturation magnetization of 151 emucm-3, which is about 40% of the bulk NiZn ferrite, was obtained under relative oxygen flow ratio of 60%.
ZnSe Quantum Dot Films Deposition from Modified Chemical Solution with Sodium Citrate
Authors: Chen Liang Yan , Zhang Li , Zhang Hao , Yang Fan , Luo Zhi Ming , Fang Chao
Published: May 2013

Zinc selenide (ZnSe) quantum dot thin films have been deposited onto microscope glass through chemical bath deposition both from original amonia free alkaline precursors and modified precursors with the adding of sodium citrate as complexing agents. The growth and optical properties of samples from original and modified precursors have been investigated. Its shown that the samples obtained with sodium citrate precursors are uniform and with stable index of refraction. And with the adding of sodium citrate, there is an increase in transmittance.
Statistical Analysis of Fatigue Crack Growth Rate of Q345E Steel
Authors: Guo En Cong , Wang Shi Yue , Liu Guo Shou , Ren Zhao Ying
Published: May 2013

Experiments of fatigue crack growth rate were conducted for standard compact tension specimen of Q345E steel; the resulting experimental data were processed by the use of incremental polynomial method for mathematical statistical analysis. The crack growth rate formula can be obtained under different survival rates by the use of Pairs Formula.
Comparison of the Simulation and Experimental Fatigue Endurance Behaviors in T6-Treated Nanosized SiC Reinforced Al Alloy Composite
Authors: Wei Yong Sen , Lu Sen Kai , Huang Ping
Published: May 2013

The fatigue endurance behaviors of SiC nanoparticle reinforced 6061 Al alloy composites (T6-treated SiCnp/6061Al) were simulated by finite element (FE) method with the help of recently developed cyclic viscoplastic constitutive model and its implementation into a FE code Solidworks simulation. The Rice-Tracey damage parameter was used for the crack path calculation did the prediction agree completely with the observed behavior. FE simulation of the materials showed that the composite samples exhibit regular crack propagation behavior. At early stages of loading the hydrostatic stress was low and the damage evolution was affected by the plastic flow. The damage grew in outer layers where the maximum equivalent plastic strain occurs. By increasing the number of fatigue failure cycles at 3×105cycles, the hydrostatic stress increased and its effect became dominant. In the 200 MPa tests the slope of the tensile portion of the hysteresis loops decreased with fatigue cycling, indicating progressive decrease in the tensile modulus. Stress concentration, due to the presence of nanoparticle reinforcements, produces controlled crack growth and higher stresses, which are related to regular energy release by the material during fracture. The need for higher stresses for a crack to propagate reveals the materials microstructural strength.
Fracture Analysis on Drainage Pipe Socket of Boiler
Authors: Xu Xue Xia , Feng Yan Ting , Wang Yong , Niu Xiao Guang , Wang Qing , Ouyang Jie
Published: May 2013

Rupture reason of boiler drainage pipe socket was analyzed by means of chemical composition analysis, macro-observation, metallurgical and SEM microstructure examination. Results showed that the rupture of the drainage pipe socket was a result of creep cracking initiated in intercritical zone of HAZ due to long period operation under high temperature. During creep process, carbides precipitated on fine grain boundaries of intercritical zone and grew up gradually into new coarse carbides as favorite nucleation site for creep void. With the growth, coalesce and connection of creep voids carries on, micro-cracks formed on original austenite boundaries and finally led to fracture of weld joint.
Tensile Characteristics of Polygonaceae Weed Roots in Slope Collapse Watershed
Authors: Zhang Xiao Ming , Ding Shu Wen , Li Shuang Xi
Published: May 2013

Root systems, as the reinforced materials, are essential to increase slope stability and mitigate soil erosion. Polygonaceae family weeds are widespread in slope collapse watershed for its rapid growth and hardiness. Some growing around farmlands and ditches affect the farm crop yield. While others growing in slope collapse have medicinal value, revegetation, and root reinforcement effect. The plant height, fresh weight and expansion range of aboveground biomass and roots were measured to research the relationship between the aboveground biomass and the belowground biomass. The relationship between the aboveground biomass fresh weight and root system fresh weight was consistent with linear function. Single root was tested by digital display push-tension meter (SH-100) fixed in vertical electrical machine (SJY-500) to obtain the relationship between tensile force and root diameter. The relationship between tensile force and root diameter conformed to exponential decay function. At last, the relationship between root diameter classes and average tensile force of Polygonaceae family weeds was analyzed. The result showed that the diameters mainly ranged from 0 mm to 2 mm, 87.75% of the total, and the average tensile force increased with the diameter class. At the beginning, the shape of tensile force was a line, then a curved line during pulling, which deformation was nonlinear. It could provide a scientific basis for design of weeder in farmland, and greening, erosion control in slope collapse.
The Fracture Failure Analysis of Shaft for Light Hydrocarbon Pump
Authors: Song Wen Ming , Yang Gui Rong , Zhang Yu Fu , Ma Ying , Hao Yuan
Published: May 2013

The failure shaft for light hydrocarbon pump was analyzed through metallographica test. The fracture appearance was examined through 3-D stereoscopic digital camera and the scanning electron microscope (SEM). The results showed that the chemical composition of the shaft was fit to the requirement of structural steel. There was sulfide inclusion distributed among the white stripe phases. The figure of phases was striation, and the direction of striation was along the direction of the axis that was the machining direction when the shaft was fabricated. The fatigue fracture was the facture characteristic because there was fatigue striation on the fracture surface. The sulfide inclusion and segregation was the main reason of the fracture.
The Effect of Microstructure on Properties of High Deformation Pipeline Steel X70
Authors: Wan X.L. , Wu K.M. , Xia Z.H.
Published: May 2013

A high deformation pipeline steel X70 with low yield ratio of 74% was achieved has been processed on an industrial scale. The impact toughness of the investigated steel is 388.3 J/cm2 at -20°C and the shear area is 97% in drop weight tear test at -15°C. The microstructure of the steel constisted of primarily acicular ferrite, polygonal ferrite and a small proportion of scattered martensite-austenite constituents. The high deformation pipeline steel had low yield ratio and good toughness, which was attributed to high Nb microalloying and rapid cooling in the TMCP process.
Numerical Solution of Constant-Q Fractional Order Integral Modeling
Authors: Li Xiu , Han Hui Li
Published: May 2013

In this paper fractional order integral model is set up about quality factor. Complex rectangular and Chebyshev polynomial are utilized to approximate the fractional order integral equation. Moreover, plane wave is used to calculate quality factor-Q. The numerical results show that Chebyshev polynomial approximation is more suitable to describe integral modeling of quality factor.
The Investigation in the Influence of Hardness to Transition Point after Tempering for Boric Carbon Steels
Authors: Chung Ho Hua , Chen Tsong Hsin
Published: May 2013

This study concerned the influence of the material strength, ductility and impact energy and the relationship of the broken section profile vs. ductile transition brittle where the steel material was treated under different tempering temperature and hardness. Generally after the steel materials, 10B35 coil wire materials which was generally applied to form screws, was treated by quenching and tempering, its hardness ranged from HRC30 to HRC45. The results showed that the elongation rate beyond 20.4% would be proportional to the impact energy with linear relation, but with reverse proportion to the hardness value. The brittle-tough point of the hardness was set around HRC37 after heat treatment in order to balance the strength and the toughness. In addition, the coil wire materials were analyzed from broken section materials showing good toughness; this represented that the area of the cross section radiation layer due to ductile fracture would largely increase. On the contrary, the wire material test fragment with bad toughness represented that the area of the shear layer due to brittle fracture would largely increase as well. As to that material, if its hardness was greater than or equal to HRC37, that material would have an excellent turning danger from transition. At the same time, when the tempering temperature of the wire steel material was set under 4600C and its corresponding central hardness was about HRC37, the distance between two cementite phase layers suddenly increased. This result leaded to the reason why the wire material test fragment was turned into brittleness from ductility. Therefore, when the fastener was manufactured under tempering treatment, avoiding the tempering brittleness temperature range was necessary.
On-Road Gaseous Emission Characteristics of China IV CNG Bus in Shanghai
Authors: Lou Di Ming , Qian Si Li , Hu Zhi Yuan , Tan Pi Qiang
Published: May 2013

In this paper, on-road CO, THC, NOX, CO2 gaseous emissions characteristics of china IV CNG bus were analyzed based on on-road vehicle emission test in the peak and non-peak hours of city traffic in Shanghai using a portable emission measurement system (PEMS). The experimental results reveal that: compared with the condition results in the non-peak hours, it (conditions in the peak hours) have lower average speed, longer idle time and shorter high speed time; the NOX emission factor and rate in the peak hour reduced by 5.66% and 70.2%; the CO, HC, CO2 emissions factors are increased by 47.2%, 32.6%, 20.8%, and the CO, HC, CO2 emissions rates reduced by 1.94%, 26.5%, 48.7% respectively, compared with that in the non-peak hours; The CO, HC, NOX, CO2 emissions factors all decreased as bus speed increased, while they increased as bus acceleration increased; the gaseous emissions rates all increased as bus speed increased; both the emissions factors and emissions rates contributions are highest at accelerations, higher at cruise speeds, and the lowest at decelerations for non-idling buses; the emissions rates under the condition of idling is lowest; gaseous emissions contribution under the various operating conditions has displayed certain correlations with the percentage of the time for different operating conditions.
The Coupled Thermal and Mechanical Load Analysis in the 6S50MC-C Type Marine Diesel' Piston
Authors: Wu Ji , Duan Shu Lin , Wu Zhan Hua , Xing Hui , Liu Qin An
Published: May 2013

MAN Diesel’s 6S50MC-C two-stroke marine diesel engine is researched in this paper. The intensity under the effect of thermal load, mechanical load and coupled loads are analyzed. As the boundary conditions of the temperature field distribution, the mean temperature and the mean heat transfer coefficient are calculated firstly. Based on the temperature field, the thermal intensity is obtained in ANSYS. Then the study analyzes the stress and the strain distribution when the mechanical load and the coupled loads are applied. Through the analysis of different loads, the maximum stress is 696MPa in thermal load, 191MPa in mechanical load and 659MPa in coupled loads. The maximum deformation is 1.011mm in thermal load, 0.147mm in mechanical and 1.022mm in coupled loads. The intensity meets the design requirement. The stress concentration and the deformation of the piston crown mainly are generated by the thermal load. To reduce the destructive effect of thermal, it requests enhancing cooling and warming up the main engine.
The Finite Element Analysis of Ultimate Bearing Capacity of Initial Bending on the T-Axis Compression Component
Authors: Han Yang Yang , Zhang Cai Xia , Li Ya Qin , Chen Si Yu , Liu Chun Shan
Published: May 2013

There is little research about the stability of T-stub steel axial compression component at home and abroad, and it remains to further investigation. On the basis of taking initial bending and other factors into consideration, through theoretical analysis and finite element calculation, this paper studies the T-stub steel axial compression buckling behavior and carrying capacity mainly using three different cross-section and different lengths ZC cross-sectional specimens.
Effect of Track Measuring Beam on the Bogie Frame Strength and Vibration Mode of Inspection Car
Authors: Wu Long Fa , Qu Sheng
Published: May 2013

Track measuring beam is the most important structure in the inspection car and the vibration characteristics of it affect the inspection results and the fatigue strength of the bogie frame. In this study, the bogie frame finite element model of a inspection car were constructed and the free mode, static strength, fatigue strength and harmonic response were analyzed. The influence of the track measuring beam installation on the local modes, static strength and fatigue strength of the bogie frame were investigated and the suggestion on the method to reduce the track measuring beam vibration and improve the inspection quality was proposed.
Finite Element Analysis for the Collapse Accident of One 110kV Transmission Tower
Authors: Jian Ming Jian , Zhang Du Qing , Zhang Guang Cheng
Published: May 2013

One collapse tower of 110 kV transmission line was taken as an example and a finite element model for the coupled tower-line system was established for investigating the effects of the strong wind on the transmission tower and line. The result shows that the selected standard of material of some rod members is lower, and the area of their section is relatively small. Main legs present buckling instability because of being in compression under action of the strong wind, which leads to the collapse accident of the towers.
20#,60Si2Mn,9Cr18MoV Steel Ferrite Area Dynamic Recovery and Recrystallization Research
Authors: Li Liang , Xiao Wen Kai , Fan Tao Tao , Zhang Zhou Quan
Published: May 2013

By using the Gleeble - 1500 hot simulation test machine we studied 20#, 60Si2Mn, 9Cr18MoV the three kinds of low, medium and high carbon steels to observe the dynamic recovery and recrystallization of ferrite while in the process of thermoplastic deformation. We calculated the hot deformation activation energy of each kind of steel by combining the stress-strain curve we got in the experiment and the theoretical model of Z parameter. It turns out Q9Cr18MoV<Q20#<Q60Si2Mn. In the meanwhile, microstructure observation through transmission electron microscope shows that the dynamic recrystallization of ferrite is more likely to happen in 9Cr18MoV steel than in 20# steel and in 60Si2Mn steel. These results indicate that the dynamic recrystallization of ferrite is not only determined by stacking fault energy but also closely related with the strain storage energy release degree.
Experimental Study of Dynamic Characteristics of Dry Friction Damping of Turbine Blade Steel
Authors: Zhao Peng Fei , Zhang Qiang , Wu Jun , Zhang Di
Published: May 2013

For lot of structures, especially turbine blades, damper can dissipate the vibration energy by friction. Investigating the property of metal dry friction damping can give many usable data for response analysis of damping blade which is important in damped blade designs. The paper constructs an experimental rig and carries out experiment with pieces having radius of curvature 6mm, 12mm and 24mm. The relative displacement between contact surfaces and the friction force changed with time were obtained for different initial pressure and frequency of exciting force. Hysteresis curves of dry friction damper were derived. The variations of friction coefficient of stick-slip area, equivalent stiffness and equivalent damping were calculated based on experimental data.
Application of CBN Cutting Tools in Hard Turning and Tool Wear
Authors: Zhao Hai Dong , An Li Bao , Yang Pei Qing , Geng Ye
Published: May 2013

Considerable research has been directed towards discovering new engineering materials for various applications. As a superhard material, Cubic Boron Nitride (CBN) has been developed and applied to engineering for several tens of years. Due to its high specific strength and stiffness as well as good creep, fatigue and wear resistance at elevated temperatures, CBN has been widely used as cutting tool material in manufacturing industry. In this paper, the preparation and characteristics of CBN are introduced. As hard turning has been more and more employed in recent years as an advanced metal cutting technique, the application of CBN cutting tools in hard turning is presented based on the literature, and in particular, the main wear mechanisms of CBN tools in hard turning are summarized, owing to the significant influence of tool wear on the tool life and product quality.
Cracking Behavior of Two Kinds of Plasma Cladding Layers by Precursor Carbonization-Composition Process
Authors: Liu Jun Bo
Published: May 2013

In-situ synthesized two kinds of Fe-Cr-C and Fe-Cr-C-Ti layers were fabricated on the base of Q235 steel by reactive plasma cladding process using composite powder prepared by precursor carbonization-composition process as raw materials. The composite powder is composed of ferrotitanium, chromium, iron and precursor sucrose. Microstructure of the layer was observed by scanning electron microscope (SEM). The phases in the layer were determined by X-ray diffraction (XRD). Results indicate that the Fe-Cr-C layer consists of primary (Cr,Fe)7C3 carbide, chrysanthemum-shaped eutectic (Cr,Fe)7C3 carbide and eutectic austenite. The cracks in Fe-Cr-C layer might originate at the interface of the layer and the base material as well as at the pores or edges of the layer. These cracks expand along primary (Cr,Fe)7C3 grain boundaries in a crystalline form. Because the grains of primary (Cr,Fe)7C3 are fiber-shaped and the fiber direction are perpendicular to the surface of the layer, so the cracks expand perpendicularly throughout of the Fe-Cr-C layer. The Ti addition into Fe-Cr-C plays an important role in synthesizing TiC and austenite, reducing primary (Cr,Fe)7C3 and improving the microstructure of eutectic (Cr,Fe)7C3. Therefore, Fe-Cr-C-Ti has good performance in toughness and crack-resistance.
Evaluation Hard Layers in Steel AISI 8620
Authors: Lopez-Perrusquia N. , Doñu-Ruiz M. A. , Cortes Suarez Victor , Sánchez-Huitron D. , Vargas-Oliva E.Y. , Perez Montes De Oca I. J.
Published: May 2013

In the present study, identify the fracture toughness and strength adhesion of borided layers in Steel AISI 8620 by boriding dehydrated paste. The formation of the borided at a temperature range of 1173, 1223 and 1273 K for 4, 6 and 8 h. X-ray diffraction analysis revealed peak of FeB, Fe2B, MoB and CrB and The distribution of alloying elements was detected by means of energy dispersive Spectroscopy (EDS), the Fracture toughness of the layers is estimated at 15 and 30 um from surface using different loads indentation Vickers, using Palmqvist crack model, the adherence of the layer/substrate was evaluate in qualitative form though the Rockwell C. The fracture toughness of the borides depends strongly on temperature and time boriding. Also, good adhesion is obtained around the Rockwell C indentation prints on the borided layer-substrate-interface.
Formation of Hard Layers in Tool Steels
Authors: Lopez-Perrusquia N. , Doñu-Ruiz M. A. , Rodríguez-González S. , Rosado Cruz D. L. , Vasquez-Ramírez Frumencio
Published: May 2013

In the present study, identify the fracture toughness and strength adhesion of borided layers on grade tools steels by Boronizing, two commonly used steel AISI 4140 and AISI 9840 are considered, the steels contain 1.0 - 0.8 wt% Cr and 0.20 - 0.25 wt% Mo, respectively. The formation of the borided layers was carried out by the powder pack boriding process at a temperature range of 1273 K for 4, 6 and 8 h. X-ray diffraction analysis revealed peak of FeB, Fe2B and CrB, the Fracture toughness of the layers is estimated at 15 and 30 um from surface using four different Vickers indentation loads, using Palmqvist crack model, the adherence of the layer/substrate was evaluate in qualitative form though the Rockwell C. The fracture toughness of the borides depends strongly on temperature and time bronzing. Also, good adhesion is obtained around the Rockwell C indentation prints on the borided layer-substrate-interface.
Process Characteristics and Experiment on Micro Arc Oxidation of Light Metals
Authors: Wang Yi , Li Hong You , Shi Mao Lin
Published: May 2013

Micro arc oxidation (MAO) is a relatively new method of surface treatments which has been used to improve the mechanical and tribological behavior of light metals. Due to the ceramic coating generated by MAO, light metals can be used more widely. The fundamental of MAO and the influence factors of MAO process are discussed here. The surface characteristics of aluminum, titanium, magnesium, Zirconium and stainless steels have been improved by MAO. Scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDS) were used to study the surface morphology and the elemental composition of the MAO coating. The EDS analysis of the coating shows the elements in the electrolyte and oxygen have incorporated into the coating.
Synthesis and Properties of Hydroxyapatite-Containing Porous Titania Coating on Titanium by Ultrasonic Shot Peening and Micro-Arc Oxidation
Authors: Deng Zhen Nan , Liu Jin Song , He Yun , Wang Si Qian , Ma Jian Feng
Published: May 2013

Titanium with surface nanostructure has superior mechanical and biological properties, which benefits titanium implants. To further improve the bioactivity of Ti surfaces, Ca/P-containing porous titania coatings were prepared on Ti with surface nanostructure by ultrasonic shot peening (USP) and micro-arc oxidation (MAO). The phase identification, composition, morphology and microstructure of the coatings of Ti with surface nanostructure during MAO were investigated subsequently. The amounts of Ca, P and the Ca/P ratio of the coatings formed on Ti with surface nanostructure were greater than those on coarse-grained Ti. Incubated in a simulated body fluid, bone-like apatite was completely formed on the surface of Ti, thus evidencing preferable bioactivity.
Influences of Surface Nanocrystallization Induced by High-Energy Spot Peening on Microstructure and Properties of Magnesium Alloy
Authors: Tang Li Wen , Sun Jian , Zhang Jin , Ou Xin Bing , Zhou Zhi Ming
Published: May 2013

As relatively new structure materials, magnesium and its alloys demonstrated significant potential for applications in many industries. However, magnesium alloys were easy to be corroded which greatly limited their development. AZ31B and AZ91D, two widely used commercial magnesium alloys in various industries, were chosen to be produced nanostructure on the surface layer, called Surface Nanocrystallization (SNC) by High Energy Spot Peening (HESP). The microstructure was characterized by Scan Electronic Microscopy (SEM) and X-ray diffraction (XRD) in this paper. Microhardness and corrosion resistance were measured by microhardness tester and electrochemical measurement system respectively. Experimental results showed that after HESP the grain sizes in the surface layer were obviously reduced into nanoscale; microhardness was greatly increased in the treated surface, about two times as much as that of original and corrosion current density in polarization curve was evidently raised while corrosion potential changed little.
Polymer Mixtures as Colon Targeted Drug Delivery Systems
Authors: Helmis Mario , Kumpugdee-Vollrath Mont
Published: May 2013

For the development of colon delivery systems (CDS) formulations have to be gastric resistant. The advantage of the CDS is the ability for a local treatment for colon diseases but also its systemic action. CDS can also increase the bioavailability of poorly water soluble drugs e.g. resveratrol, which can be degraded in the upper gastrointestinal tract or by the First-Pass-Effect. In this project the coating technique with different polymer mixtures containing Kollicoat MAE-30DP, Eudragit-NM, Eudragit-L, and Eudragit-NE was investigated. Resveratrol was used as a model drug and all formulations were coated with a polymer mixture in a small scale fluidized bed apparatus. Morphology, roughness and film thickness of the coated tablets were determined by a scanning electron microscope and a 3D light microscope. Drug amount was determined by UV-spectrometry. Release studies were performed in a dissolution apparatus type II. Kinetic profiles of drug release were demonstrated. Results exhibit the advantages of polymer mixtures for CDS in comparison with results of pure Kollicoat MAE-30DP which were published in one of our latest publications.
Structrure of Al2O3 Ceramic Coating on Super Alloy Prepared by Cathodic Plasma Electrolytic Oxidation
Authors: Wang Yun Long , Wang Miao , Qin Yue Mei , Shi Xing Feng , Guo Hui Rong , He Zi Juan
Published: May 2013

Al2O3ceramic coating was successfully prepared on GH132 super alloy by cathodic plasma electrolytic oxidation in (NO3)3·9H2O electrolyte. The structure and chemical composition of the coatings were characterized. The results showed that the as prepared coating was composed of Al2O3crystal, including much α-Al2O3andsomeγ-Al2O3two types of Al2O3.A few Fe elements entered into in the substrate and nearly no other elements were found in the coating surface. The Al2O3.coating showed coarse surface and there were some small pits on the surface. The diameters of pits were not more than 20 um. The thickness of coating was about 50μm.
Electroless Nickel-Phosphorus Plating on TiB2 Powder
Authors: Sun Shuo , Su Bo , Shi Wei
Published: May 2013

Electroless deposition technique was used to coat Ni-P on TiB2 particles by activating the TiB2 powder in a furnace at 400 ◦C for 1 h. Scanning electron microscopy images and EDS spectra before and after electroless nickel plating confirm that nickel is deposited on the surface of TiB2 particles. With the increase of heat treatment temperature, coating weight is increased firstly and then decreased, and reached the maximum value at 400 ◦C. XRD results show that the Ni-P deposit was predominantly amorphous. However, after heat treatment, the metallic deposits can easily transform into crystalline Ni and Ni3P phases, as confirmed by DSC and XRD analyses.
Analysis and Research on the Failure Mode of Large Automobile Stamping and Countermeasure
Authors: Pan Guang Yong
Published: May 2013

In this paper, first of all quality requirements of the large automobile stamping was introduced. Based on investigation, the main failure forms of species and its related influencing factors were determined, and analyzed the stamping wrinkling and cracking mechanism of failure modes. Finally the corresponding countermeasure was proposed. The paper can provide valuable referenced for domestic research institutes and automobile production enterprises.
Continuous Cooling Transformation Behavior of X70 Pipeline Steel
Authors: Yang Hong Mei
Published: May 2013

The continuous cooling transformation behaviors were researched on X70 pipeline steel through two pass deformation and non-deformed austenite using Gleeble-3500 thermal mechanical simulator, and static continuous cooling transformation curve and dynamic continuous cooling transformation curve were measured through thermal dilation method and metallographic method. The influence of cooling rate and deformation parameters on microstructure was analyzed. The results show that the hot deformation accelerates the acicular ferrite and polygonal ferrite phase transformation, increases the starting transformation temperature and the finishing transformation temperature significantly, and shifts the CCT curve moving upward to the left side corner. Acicular ferrite is obtained in practice using accelerated cooling rate after deformation Acicular ferrite can be obtained in wider range of cooling rates, and microstructure and island structure is finer through hot deformation.
Forecast of Shrinkage Porosity of Aluminum Wheel Liquid Die Forging in Solidification Process and Process Optimization
Authors: Yang Hai Bo , Zhao Xing Sheng , Fan Wei Zhong , Chen Xue Wen , Xu De Ying
Published: May 2013

Using ProCast casting simulation software, the solidification process of the Aluminum Alloy steel casting was simulated according to its scene casting process, and the shrinkage porosity defect was forecasted. Based on the simulation, the casting technology was improved using the orthogonal test. An optimized plan was obtained, which provided a reference for the actual production of the casting.
Study on the Flow Stress of the High-Mn Austenitic Steel during Hot Deformation
Authors: Xu Xin , Li Fang Po , Feng Chun , Wang Peng , Song Sheng Yin
Published: May 2013

The flow stress of a high-Mn austenitic Fe-20Mn-3Si-3Al TRIP steel was investigated by isothermal compression tests on Gleeble 3500D thermo-mechanical simulator in the temperature ranges from 900°C to 1100°C and the strain rate ranges from 0.01s-1 to 10s-1. The results show that the flow stress is sensitively dependent on deformation temperature and strain rate, and the flow stress increases with strain rate and decreases with deformation temperature. The flow stress during isothermal compression can be described by the Zener-Hollomon (Z) parameter in the hyperbolic sine equation with the hot deformation activation energy Q of 385.2kJ/mol.
Study on the Parameters of Piercing Die with Finite Element Method
Authors: Yang Yan Xiong
Published: May 2013

This paper focused on the piercing process in order to obtain the optimum mold parameters with the finite element method. In present investigation, the clearance, punch-die round radius and the interaction of between clearance and punch-die round radius were studied by simulating the piercing operation of a Q235 sheet. Simulation used the FEM program ANSYS. The results of the present paper showed that clearance was the most influential factor for piercing, and numerical experiments was an effectiveness method to get optimal parameters of mold parameters, and the numerical experiment results showed that the best clearance could be got.
A Review of Liquid Forging Process
Authors: Huang Xi Na , Zhong Zhi Ping , Wang Wei , Li Feng Jiao , Qiu De Hua , Peng Chong
Published: May 2013

Liquid forging is a new technology of plastic forming. It is a kind of bulk forming process with liquid metal with high-quality and efficiency and it has the characteristics of both die casting and forging. This paper will discuss the liquid forging process, die design, simulation and optimization of liquid forging [1].
FEM-Based Analysis on the Process of Tube Stamping
Authors: Wang Zhi Ming , Dong Shen , Li Fu
Published: May 2013

Pipe stamping processing is a new kind of processing method ,which is high efficiency, low cost, low energy consumption .It has the very high practical value. Aiming at the tube punching force and deformation characteristics, the application of plastic finite element method was used to study the tube punching main process parameters on forming after the influence of wall collapse. Research shows that: wall collapse as tool feed speed increases first increases, then decreases to a certain degree; Along with the fixed die mandrel increases ; With the increase of the wall inside diameter increases.
Finite Element Analysis of Main Stand of Ф140 Pipe Rolling Mill and Split Casting
Authors: Han Ming Bo , Sun Li Fei
Published: May 2013

By using finite element software, the paper establishes the main stand analysis model of the Ф140 pipe rolling mill and provides the model analysis of main stand in cases of full load. Verify the design of main stand fully comply with the technical requirements .In this paper, it provides the theoretical position of split casting and welding method using electric slag welding.
Flow Stress Models Analysis for Metal Powder Forming Simulation
Authors: Liu Ming Jun , Chen Hua Ping , Jiang Jun Xia
Published: May 2013

Powder forming process can produce parts with homogeneous and satisfactory mechanical properties. Based on the assumption that the powder system is a compressive continuous material, the flow stress models used in powder forming were analyzed. The correspondent elasto-plastic constitutive model was derived from the yield criterion. Appropriate algorithm and mechanical models were applied. The program was developed and three-dimensional simulations for the powder compaction process of the iron matrix powder were performed. Effects of different flow stress models on simulation results were analyzed.
Pulse Current Auxiliary Tensile and Bulging of Light Metal Alloy
Authors: Liu Jing Yuan , Zhang Kai Feng , Jiang Shao Song
Published: May 2013

Pulse current effects during hot tensile process and superplastic forming process of AZ31 magnesium alloy and TA15 titanium alloy were investigated in this paper. The experimental results indicate that the current can produce polarity effect to coarse grain AZ31 magnesium alloy, but to fine grained TA15 titanium alloy, the polarity effect is not obvious. The impact of electron wind force can change the strength of material during tensile process and affect final shape of part, making the dome of AZ31 hemisphere part deviated from the axis to the side of positive pole during superplastic forming process. In addition, the impact of current depends on current density and dislocation density.
Rolling Force Prediction System of Cold Rolling Process Based on BP Neural Network
Authors: Teng Wei , Wang Guang Ming
Published: May 2013

This paper took the example of rolling force prediction in the cold rolling process to describe the establishment and application of BP neural network prediction system. This system is a prediction model for generic process. Users can select different parameters to train the network structure according to their needs, and can calculate relative rolling force parameters based on the known structure. This system can provide very valuable process information for workers and researchers .
Research on Using Limestone for Slagging during BOF Steelmaking Process
Authors: Feng Jia , Li Hong , Li Chen Xiao , Song Wen Chen , Nian Wu , Guo Luo Fang
Published: May 2013

This paper introduced the primary research on the method of using limestone instead of lime for slagging during BOF steelmaking. The study showed that the heat is sufficient for limestone to completely replace lime on the condition that the ratio of hot metal to ferrous scrap is adjusted properly. According to thermodynamic calculations, the partial pressure of CO2at the hot metal surface at the early stage of converter steelmaking is close to 0 and nearly all the CO2can react with elements in hot metal, producing CO and reducing O2consumption. Slag with high oxidizability, high basicity and relatively low temperature can be formed quickly by using limestone, which is advantageous for dephosphorization. Industrial tests showed the endpoint Lp rises with the proportion of lime replaced by limestone increasing. CO2volume expands by 4000~30000 times when limestone is heated at extremely high speed in converter, resulting in the fragmentation of some parts of limestone and the increase of the contacting area of limestone and slag. The unreacted core model with surface exfoliated was introduced.
Small Module Involute Spline Processing with Position Requirements
Authors: Zhang Bao Guo
Published: May 2013

Spline shaft is widely used as one of the important parts in machinery. Cold rolling process is currently the main processing method to small module splines.For the spline with position requirements, that is: one of the spline tooth is located at an angle of the spline shaft cross section, cold rolling processing can't guarantee the spline tooth position. The paper analyzes the defects existed in the rolling and processing of this kind of spline. Through transforming a hydraulic press and design special frock clamp to ensure the spline tooth position angle, the small modulus involute spline processing with position requirements is realized in the way of punch press processing.
Chip Formation Simulation in FE Modeling for Machining FRP Composite
Authors: He Yan Li , Ma Hai Ying , Wang Jing Yi
Published: May 2013

The influence of chip formation technology on the simulation of machining unidirectional fiber reinforced polymer composite (FRP) is investigated. Two-dimensional macro-mechanical FE model was developed for orthogonal machining. Tsai-Hill failure criterion was implemented in VUMAT Abaqus subroutine. Two different chip formation technologies were simulated, analyzed and compared with experiment in literature. The results show that chip formation technology makes a difference in FRP machining simulation for various cutting conditions. Though chip shape, cutting forces and sub surface damages predicted by ALE model are more reasonable than that by element deletion model, predictions in both models are not satisfactory due to inherent limitations associated with the macro mechanical FE model and Tsai-Hill damage criterion.
Experiment on Surface Roughness and Acoustic Emission Signal in Infeed Period of Cylindrical Plunge Grinding
Authors: Li Hao Lin , Cao Hao Yang , Jiang Chen
Published: May 2013

This work presents an experiment research on Acoustic emission (AE) signal and the surface roughness of cylindrical plunge grinding with the different infeed time. The changed infeed time of grinding process is researched as an important parameter to compare AE signals and surface roughnesses with the different infeed time in the grinding process. The experiment results show the AE signal is increased by the increased feed rate. In the infeed period of the grinding process, the surface roughness is increased at first, and then is decreased.
Study on Desulfurization Kinetics Model of LF Refining
Authors: Yue Yu , Zhang Bo , Xue Zheng Liang
Published: May 2013

The desulphurization kinetics in ladle refining was analyzed, and the restrictive link for the desulfurization was selected based on previous research. Then the kinetics of desulfurization model in LF refining was developed and the empirical formula of sulfur ratio was summarized. The result by calculated shows that there is a good linear correlation between desulfurization rate and time, and the mass transfer coefficient D=3.79x10-5m/min.
Modeling and Analysis of Machining Force in Elliptical Vibration Cutting
Authors: Lin Jie Qiong , Liu Jian Hua , Gao Xiao Ping , Wang Shu Qing
Published: May 2013

Elliptical vibration cutting (EVC) is one of the main methods to use diamond tool machining of hard to cutmaterial. Accurate prediction of cutting force in elliptical vibration cutting process is not only an important basis to properly choose of cutting parameters and optimal tool geometry parameters, but also a key factor to improve the processing property of cutting. A method to build cutting force theory model in EVC is presented in this paper. Eigen decomposition of the elliptic motion locus first ,then getting the piecewise function of the cutting force model. Based on simulation analysis of the cutting force model, this paper predict the rules that vibration amplitude and angle of tool geometry affect on cutting force, which provide theory basis for choose cutting parameters and cutting tool parameter in EVC.
The Influence of Variable-Speed Waveforms on Vibration Suppression in Time-Varying Speed Cutting
Authors: Cong Juan , Wang Yun , Yu Wei Na
Published: May 2013

Through the research on the change of system input and output energy in time-varying speed cutting, the influence of variable-speed waveforms on vibration suppression effect in time-varying speed cutting is quantitatively analyzed in this paper. A conclusion can be drawn that sine wave speed variation is better than triangle wave speed variation in vibration suppression.
Drilling Simulation of Carbon Fiber Reinforced Plastic Composites Based on Finite Element Method
Authors: Sha Zhi Hua , Wang Fang , Zhang Sheng Fang
Published: May 2013

Carbon fiber reinforced plastics are widely used in aerospace and aircraft industries because of their remarkable advantages such as lightweight and high strength. However, as their properties are different with metals, those materials are difficult to machine in conventional ways, the machining defects may appear and the machining accuracy and surface quality are difficult to guarantee. Oriented to drilling of carbon fiber reinforce plastics, a machining model based on finite element method are presented in this paper, the drilling simulation of carbon fiber reinforced plastics using Deform-3D are realized, and the factors which influence the machining quality of the hole are analyzed in-depth. It shows the simulation results are accord with the results from the literatures and experiments and can used as evidence in drilling parameters optimizing and drilling quality improving.
Study on the Ultrasonic Characteristics in the Contact Interface under Ultrasonic Cutting
Authors: Zhang Ming , Liu Zheng , Jiao Feng
Published: May 2013

The ultrasonic transmission model is established in the ultrasonic cutting process based on the ultrasound oval cutting device made by ourselves and the different vibration cutting effects is analyzed under the ultrasonic cutting process in this paper. The ultrasonic transmission at the contact interface is vulnerably affected by preload force factors and so on by the vibration experiments of the ultrasonic vibration cutting system.
Effect of Magnetic Field Current on Microstructure and Properties of AZ91 Magnesium Alloy Welded Joint
Authors: Su Yun Hai , Lin Jin Liang , Kan Zhi Peng
Published: May 2013

In this investigation, in order to research the influence of magnetic field on microstructure and properties of magnesium alloy welded joint, the AZ91 magnesium alloy plates were welded by GTAW under AC longitudinal magnetic field. The tensile test, EDS and XRD were used to analyze the properties and microstructure of welded joint under different magentic field current. The acting mechanism of magentic field on welded joint was studied. The results show that, the optimal mechanical properties will be obtained when Im=1A, which the ultimate tensile strength is 270MPa and the elongation precentage is 7.1%.The magnetic field can produce electromagnetic stirring, which can refine crystal grain and improve the solubility of alloy element. The properties of welded joint will been improved by these fine crystal grain.
Effects of Welding Heat Input on 22MnB5 Steel with Hot-Dipping Al Coating
Authors: Wang Chun Yu , Li Lei , Li Huan Ran , Qin Chun Lin , Zhao Hong Yun
Published: May 2013

The hot-dipping Al coating was developed on 22MnB5 steel surface. Effects of heat input with different welding parameters were investigated in this paper. It describes an approach to optimum the heat input of Al coating on 22MnB5 steel. The results of optimum heat input show that ~3840J/cm has the best tensile strength, whose corresponding welding parameters are optimum for hot-dipping Al coating steel. The proper hot-dipping time (~2min) of Fe-Al compounds between Fe substrate and Al coatings must be selected (750°C, hot-dipping 2min) in order to decrease the finger-like growth of 22MnB5 steel surface coatings.
Modeling and Simulation on Temperature Control System for Hot Pressure Welding
Authors: Xie Bing , Hu Fang , Chen Shi Min
Published: May 2013

Hot pressure welding (HPW) is one of the inner lead bonding process which is widely used in microelectronics manufacturing. This paper presents a practical digital temperature controller for HPW. Based on the step response, an identification method is developed to obtain a nonlinear time-delay model for heating-up control design. The input-output linearization problem is solved by means of second-order Pade approximation and static inverse transform, and an optimal controller is obtained for the welding machine. The experimental equipment on the temperature control is designed based on LabVIEW and data acquisition card. Simulation and experimental results show that the dynamic performance, steady stage error and overshoot satisfy the designed requirements.
Mechanism Research on Residual Stress's Elimination of Aluminum Alloy Welding by Ultrasonic
Authors: Cui Gao Jian , Lv Ting Ting , Zheng Xue
Published: May 2013

Through analysing the shortcomings of the traditional methods of eliminating residual stress, and aimed at the mechanism of eliminating residual stress, put forward the method of eliminating aluminium alloy welding residual stress by ultrasonic. Explained the superiority of using ultrasonic to eliminate aluminium alloy welding residual stress by the comparison with heat treatment and vibration processing that are the most commonly used methods in practical engineering.
Properties Effect of 16MnR Steel Weld Joint by Different Welding Methods
Authors: Guo Lin , Zhang Tian Hui , Xu Ren Ping , He Hui
Published: May 2013

Welding experiments were made with δ=14mm, 16MnR steel by three welding methods, manual electric arc welding, automatic submerged arc welding and semi-auto solid-core CO2 shielded arc welding, and weld joint test with samples from every welding specimen. The properties of welding joint were analyzed by three welding methods and in every position of welding, concluded that brittlement problems in heat affected zone arise from the CO2 shielded arc welding, it is because of the heat damage of alloy elements of weld joint metal while using CO2 shielded arc welding, but the strength of the weld joint is high because of its high fusion ratio. So for improving the mechanical properties of weld joints.it had better accelerate the cooling rate of weld bead and decrease the heat input of welding.
Research on Welded Pipe and Tube Pass Design Virtual Methods
Authors: Li Guo Chang
Published: May 2013

Welded pipe and special pipe get more and more applications; however, the difficulty of pass design method limits welded pipe manufacture. The paper discusses welded pipe roll pass design method based on CATIA, and roll CAD/CAPP computer aided design system based on AutoCAD, and gives roll virtual design methods which use roll CATIA, CAD/CAPP system.
The Temperature and Residual Stress Distributions of Butt Weld Pass on Nickel Alloy 690 Plate
Authors: Yin Chun Ho , Hsu Chao Ming , Kuang Jao Hwa
Published: May 2013

The variations of temperature profile and residual stress distribution in the single V butt welds were studied in this work. The thermal elastic-plastic model of ANSYS finite element analysis software is employed in this study to simulate the melting and solidification processes of two clamped nickel alloy 690 plates with different welding parameters; i.e. the welding speed and the number of weld passes. The temperature dependent material properties are used. The effects of these welding parameters on the residual stresses around the weld are investigated. Numerical results reveal that these welding parameters may affect the distribution of residual stresses significantly.