bluuebunny/crossref_metadata_2025 huggingface dataset:
Finite Element Analysis of Friction Effect on Deformation Behavior of Copper Rods in a Modified C2S2 Process
Authors: Wei Wei , Wei Kun Xia , Zhang Wei , Du Qing Bo , Hu Jing
Published: November 2012

The influence of friction on deformation behavior of copper rods during the continuous ECAP process (a modified C2S2 for the processing of rods and wires) was analyzed by using DEFORM-2D finite element method. The effect of friction on the stress and strain distribution, strain homogeneity and the torque-time curves was investigated. In the modified C2S2 process, the effective stress distributions are symmetrically concentrated on the shear plane, but there is an inadequate length of the plastic deformation zone. The effective strain shows a distorted fan shape in the shear deformation zone. As the friction factor increases the distorted fan shape tends to be normal and thinner, indicating that the bigger the friction factor, the more homogeneous the shear deformation. The effective strain is uniform across more than 70% thickness of the specimen. The assumed shear deformation is further divided into three stages, which can be explained by the torque-time curves.
Simulation of the Wind Field of Gantry Cranes Based on FLUENT
Authors: Hu Jing Bo , Chen Da , Ding Shu Qing , Qing Guang Wei , Jin Hui
Published: November 2012

The wind load on large cranes with great windward areas cannot be ignored. The simulation of wind field is to determine the accurate wind force acting on different parts of cranes and serves as the basis of the windproof design. Taking 300t shipbuliding gantry crane as the study object, this paper uses computational fluid dynamics, calculates the mechanical response of cranes by FLUENT, obtains the graphs of pressure, streamline, force distribution of cranes under different wind loads. Through the result analysis, dangerous force position is pointed out. And the ideas of structural methods to improve the windproof ability of cranes are also proposed.
Study of Wettability of Vinyl Resin on Carbon Fiber
Authors: Sun Hong Qiang , Wu Xiao Qing
Published: November 2012

The tensile performance of the vinyl resin casting body, epoxy resin casting body, carbon fiber(CF) reinforced vinyl composites and CF/epoxy composites has been presented. The morphology of tensile fracture surface of CF/epoxy and CF/vinyl has been compared, and the interface adhesion has been analysed. The results show the tensile strength for vinyl resin casting body is lower than epoxy resin casting body’s, the tensile modulus of them are close. But the tensile strength and modulus of CF/vinyl composites are both close to CF/epoxy composites. And the vinyl has the better interface adhesion and wettability on CF than epoxy.
Research and Application of Wire Cutting Mold Surface Roughness
Authors: Shen Xiao Long , Zhang Lai Xi , Yu Nan Lin
Published: November 2012

The article aimed at mold parts surface machining, has been studied high speed wire cutting technology. Explored the process evaluation factors which impact wire cutting mold based on the theoretical analysis of the wire cutting discharge gap and the surface processing finish of the mold parts. By studying the two main elements which affect the mold parts surface roughness processing, measures of improve and enhance wire cutting mold surface roughness are proposed. Only the comprehensive account of various factors can obtain mould parts processing good surface quality. The research methods and conclusion have provided reference on solving the problem of mold parts surface roughness by WEDM.
A Study on DOE Methods for Hydromechanical Deep Drawing Process Parameters
Authors: Halkacı Mehmet , Halkaci Huseyin Selcuk , Turkoz Mevlut , Dağhan Behçet
Published: November 2012

Formability of sheet metals can be increased by Hydromechanical Deep Drawing (HDD) process. Formability of the deep drawn cups is generally assessed by Limiting Drawing Ratio (LDR) which is the ratio of the blank diameter to punch diameter. In order to increase LDR by HDD, process parameters of the HDD should be arranged properly. Arranging of the process parameters requires a great knowledge about the effects of the process parameters to certain performance criteria of the process. Determining of the effects of the process parameters by full factorial experiments is a hard duty. Hence certain statistical methods that decrease the number and the cost of the experiments and reduce the time should be used to find effective parameters and their appropriate levels. In this study orthogonal experimental array was applied and effective process parameters were determined by analyzing predicted data with Taguchi's robust parameter design method and ANOVA method. Then the results were compared with each other to evaluate differences between the methods. By using the appropriate levels of the parameters the LDR of AA 5754 aluminum alloy which uses in automotive industry intensely was determined.
Deformation of Serrated Chips Based on Minimum Energy Consumed for High Speed Machining
Authors: An Hu Ping , Rui Zhi Yuan , Wang Rui Feng , Zhang Zhi Mei
Published: November 2012

The geometrical model for serrated chip was set up by studying the characteristic of typical chip during high speed machining. According to the adiabatic shear theory under the condition of high speed machining, friction force and flow velocity on back surface of chip as well as shear force and shear velocity on sliding plane were obtained by establishing mechanics and kinetic models via analyzing equilibrium forces exerted on the saw-tooth chip at the moment when the catastrophic thermoplastic instability occurred on slippage plane, then energy equation for cutting was offered. With strain, strain ratio, cutting temperature and deformation hardening considered, deformation equation was found using the principle of minimum energy. Finally, deformation equation and factors that affect deformation during high speed cutting were ascertained by combining analysis of deformation curve with cutting theory.
Concrete Crack Control Technology in Chongqing Inch Container Terminal Box Letter of Application in Engineering
Authors: Fu Ya Nan , He Ze Ping
Published: November 2012

This paper mainly introduces the main causes of the concrete cracks, and with Chongqing inch beach bonded port freight container terminal, drain tank letter concrete crack control as the engineering example, the paper analyzes the method of crack control. For example reduce water consumption, choose the narrow fly ash cement, reduce the narrow concrete constraint, and control the hydration heat, strengthen the concrete curing, control the steel corrosion of crack, control the box by letter of the surrounding rock deformation, they can be reached that box culverts basic don't crack effect.
Finite Element Numerical Simulation of Tubing Premium Connection
Authors: Zhang Fu Xiang , Ji Bing Yin , Yang Xiang Tong , Han Yong , Chang Ze Liang
Published: November 2012

The environment and load condition of tubing is severe in high pressure wells. The sealability and joint strength of tubing string plays an important role in production operation. In this study, the makeup, sealability and joint strength was analyzed from conditions of make-up loading, tension loading, compression loading and internal pressure loading by finite element method. The makeup torque, the contact pressure distributions of metal seal along the axis and the stress distributions of threaded connection are given. The results show that under tension loading, compression loading and internal pressure, the overall stress level of threaded connection is lower than of pipe. The anti-compression performance and joint strength of threaded connection is greater than of pipe. The contact pressures of metal seal maintain relatively high level of contact pressures under tension loading, compression loading and internal pressure. Tension loading and compression loading reduces the sealing performance and the internal pressure increases the sealing performance from the integral of the contact pressure.
Rebound Deformation of Thin Part Caused by Clamping Force in End Milling
Authors: Liu Yu Mei , Jiang Zhao Liang , Liu Wen Ping , Li Zhi
Published: November 2012

Deformation mechanism of low-rigidity thin part caused by clamping force is studied in this paper. A coupled thermo-mechanical simulation process of aluminum alloy 6061 is developed using the finite element method with Abaqus. The results of simulation are verified by experimental measurements of cutting force and surface residual stress. Then using the model investigates the effect on residual stresses along the thickness of aluminum alloy 6061 load and unloadthe clamping forces. The deformation condition is also studied after removing fixing.
In Vitro Study on Dental Abrasive Finishing of Restorative Ceramics Using Diamond Burs in Dental Surgery
Authors: Geng Ke Tao , Wang Yu Guo , Song Xiao Fei , Wan Shu Min , Lin Bin
Published: November 2012

With the aesthetics’ enhancement, there is a growing demand for the use of restorative ceramics in dental surgery. However, ceramic materials are hard and brittle, and problems such as surface damage, crack, and fatigue were easily produced in dental abrasive finishing. Consequently, these flaws could cause the strength decrease of the ceramic, which manifest the shortage of the lifespan in dental. Contraposing these problems, a high-speed handpiece with diamond burs was used when finishing the leucite glass ceramic in the dental surgery. In this paper, finishing force, specific energy and surface integrity including the roughness and morphology were observed. the results revealed that both normal and tangential forces increased with the increasing of feed rate and depth of cut, while there is an apparent decrease of the specific energy. These two parameters were bigger in the up finishing than that of down finishing. Finishing parameters have little effect on surface roughness, according to the observation of a scanning electron microscope. It is easily found that the finished surface was consisting of brittle fracture and plastic deformation. For comprehensive, good surface quality could be obtained in the down cutting other than up cutting.
Influence of Technological Parameter for Ramie Yarn Hairiness on Compact Spinning with Suction Groove
Authors: Ma Hong Cai , Cheng Long Di , Yan Gui Xiang , Xu Shi Ping
Published: November 2012

The application of compact spinning technology with suction groove for ramie was studied. This technology improved ramie yarn hairiness, breaking strength and so on. The performance of the yarn hairiness was analyzed in detail through contrast test of the compact spinning technology with suction groove and the traditional ring spinning for ramie fiber. At the same time, the comprehensive performances of ramie yarn spinning by the two kinds of spinning technologies were contrasted and analyzed. The results showed that the spinning technology with suction groove can be significantly improved ramie yarn properties: hairiness and breaking strength etc. In the spinning technology with suction groove, the optimal technological parameter for producing least yarn hairiness, A1 B1 C1 D1, is acquired, where the spindle speed A is 6600 r/min, twist B is 608 T/m, the value of negative pressure C is -3.1 kPa, and traveler D is 21 # (yarn Nm 36).
Rotary Ultrasonic-Assisted Grinding of Ceramic Material
Authors: Chai Jing Fu , Song Wen Qing
Published: November 2012

The engineering ceramic material is hard to machining with the hard and brittle characteristics, so we are using a precision machining method of the rotary ultrasonic assisted grinding. In this paper, a research on the rotary ultrasonic assisted grinding mechanism of zirconia ceramic material is described. We use an experimental method of the orthogonal combination to complete an experiment of the rotary ultrasonic grinding of zirconia ceramic material. According to the experiment, we explore how the various grinding parameters affect the surface roughness, and determine a set of the optimal grinding parameters.
Study on Roller Profile for Cam Forming by Cross Wedge Rolling
Authors: Zheng Zhen Hua , Wang Bao Yu , Hu Zheng Huan
Published: November 2012

Based on the motion relation between rollers and work piece during cross wedge rolling (CWR) process, roller profile equations for cam forming were studied. A three-dimensional entity model of the roller was established using the profile equations. Process of cam forming by CWR was simulated by DEFORM-3D. The FEM data was used to analyze dimensional accuracy of the formed cam. Results demonstrate that the equations can be used in roller design for cam rolling.
Structure Design and Experimental Research on Spiral Boring Tool
Authors: Guan Shi Xi , Wang Ling Jun
Published: November 2012

Spiral boring tool is widely used in the manufacturing of the deep spiral groove. Based on the design of spiral boring structure, study on it by stress analysis and experiment, then get the change situation of force and torque in the given processing conditions, this provides a method basis for the study of spiral boring tool.
The Effect of Welding Materials on 1Cr18Ni9Ti and 2Cr13 Steel Welding Joints Microstructure and Mechanical Properties
Authors: Zhao Yong Tao , Liu Zong Chang , Zhou Jun Wei
Published: November 2012

By method of TIG, under certain welding craft conditions, two kinds of welding wire were added,1Cr18Ni9Ti and 2Cr13 steel were welded. By (ZEISS) OM, SEM, the microstructure of two kinds of 2Cr13 and 1Cr18Ni9Ti welding joints were observed and analyzed, by electronic universal tensile machine, mechanical properties of welding joints were measured. The results show that 2Cr13 and 1Cr18Ni9Ti welded joints is typical columnar crystal, the microstructure is lath martensite + residual austenite + carbide; the micro-hardness of two kinds of welding joint changes fluctuantly, it increases firstly and reduces secondly, the value is up to max in welded joint zone. The welding joints filled in two kinds of materials, tensile samples rupture forms are toughness rupture; plasticity and strength of welding joint filled in ER308 welding material is better than that of welding joint filled in H1Cr21Ni10Mn7Mo welding wire. On the contrary, its hardness is lower than that filled in H1Cr21Ni10Mn7Mo welding wire.
Temperature Field and Extrusion Load in Needle Piercing Extrusion Process Based on Ingot Billet for Large 7075 Aluminum Alloy Tube
Authors: Guo Liang Gang , Dong Ke Ke , Yang He , Zheng Wen Da , Zhang Jun
Published: November 2012

Abstract. The change rules of the billet temperature field and extrusion load are the significant basis for the optimal design of the needle piercing extrusion process based on ingot billet for the manufacture of large-diameter thick-walled tube. Taking the needle piercing extrusion process of a 7075 aluminum alloy tube with sizes of Φ500mmx400mm/6000mm as study object, we developed a precise FE model for the process under DEFORM-2D environment, then numerically revealed the distributions and evolution rules of the billet temperature field, and obtained the effects of the extrusion speed and initial billet temperature on the billet temperature filed and extrusion load. The results show that the peak extrusion load decreases linearly with the increase of initial billet temperature but is insensitive to the extrusion speed, and that the peak temperature rises with the increase of the extrusion speed and initial billet temperature, and always locates on the surface of the initially extruded tube close to the exit of the cavity die.
Stress Field Simulation of Compound Cast Rollers during Centrifugal Casting Process
Authors: Liu Li Gang , Yu Hui , Wang Yu Hui , Yang Yu Dong , Liang Cong Tao , Li Qiang
Published: November 2012

The stress field of compound cast rollers during centrifugal casting process was investigated in this work. A finite element (FE) model was built to simulate the internal stress fields during cooling process, in which phase transformation was considered. The mechanical parameters employed in stress numerical simulation were measured by using thermal/mechanical simulator. The residual internal stress of the compound cast roller by centrifugal casting method was measured by using X-ray stress analyzer. The simulated results are in agreement with the measured ones very well. According to this model, the temperature and stress fields of the compound cast roller during centrifugal casting process were simulated.
Effects of Press on Compression Molding Bonded NdFeB Magnets’ Quality
Authors: Qin Wan Zhong , He Jie , Meng Jia Hong
Published: November 2012

Compression molding is the most important making method of bonded NdFeB magnets. Characteristics of bonded NdFeB magnets are analyzed. Based on test, research and lot production practice, the important effects of mould structure, press structure and compression molding actions on magnets’ quality are introduced, The key techniques that controlling the quality of bonded NdFeB magnets are summarized.
Research of Fatigue Stress Cracking for Injection Mold Cavity Based on Ansys Workbench
Authors: Hu Qing Chun , Song Ke , Jiang Xiao Ping
Published: November 2012

The process of injection molding, packing and cooling for injection mold PET (Polyethylene terephthalate) cavity was analyzed and the cause of fatigue stress cracking was investigated. An analysis method of injection mold cavity fatigue based on Ansys Workbench(AWB)was put forward. A simulation of temperature field, displacement, thermal stress field and fatigue life for the cavity of a work cycle based on heat transfer theory was completed. Provide effective measures to avoid fatigue stress cracking and optimization design of the injection mold.
Mechanism for Mechanical Properties of the A357 Connection Beam Casting from Solidification
Authors: Fan Zhen Zhong , Li Jiong Li , Li Sha Sha
Published: November 2012

The overall distribution of mechanical properties of A357 aluminum alloy connection beam casting after solidification and T6 heat treatment was researched in this paper, through the mechanics performance test, metallographic microstructure observation, SEM and EDS scanning analysis of the fracture surface, the ensemble mechanical properties of connection beam casting was characterized. The results show that owing to the low cooling rate nearby the arc thick-walled department and the trasition region between the thick and thin-walled of the connection beam casting, leading to the morphology of the crystalline grains and silicon particles in this vicinity are thick. Some casting defects such as oxide inclusions located in the lateral stud district were caused by the strong erosion of high temperature melting liquid during the pouring process, resulting in the mechanical properties decreased significantly, casting defects were not eliminated in the T6 heat treatment process. Due to both the high cooling rate and the smooth pouring process among the thin-wall, forward stud and square box region of A357 aluminum connection beam casting, after the solid solution and limitation strengthening of T6 heat treatment, resulting in the overall mechanical properties were higher than other areas. The tensile strength has reached 360.96MPa, also with the yield strength and elongation respectively attained 297.95MPa and 8.82 %.
Research on Friction Behavior in Tube Hydroforming Process
Authors: Zheng Zai Xiang , Xu Jing , Liu Guo Xian
Published: November 2012

In the tube hydroforming process, the friction behavior between the tube blank and the die is very complex. As a result, it is very difficult to build a precise friction model in accordance with the actual working conditions by fully taking into account the various factors. In this paper, the friction behaviors between the tube blank and the die in the guided, transition and expansion zones have been studied with the help of numerical simulation and experimental tests. The influences of the different friction conditions in the three zones as well as the uneven friction behavior in the expansion zone on the thickness distribution of tube wall and the characteristics of material flow have been analyzed and experimental tests have been carried out for the verification. The conclusions have provided theoretical references for the process planning, selection of lubrication and tooling design in the actual production process of tube hydroforming.
Predictive of Electron Beam Focus Position by Metal Powder Temperature
Authors: Chen Yun Xia , Li Guo Hua , Wang Xiao Jing
Published: November 2012

The equipment for measuring electron beam (EB) focus in electron beam produced by the effect of extremum temperature of powder molten pool caused by the interactive effect of electron beam with metal powder is described. The principle of operation of apparatus and examples of EB characteristics are presented. During electron beam processing, the mechanical analysis of metal powder molten pool temperature following focusing current are studied. As a result, the transferring point of critical energy density described by the peak of metal powder pool temperature can be obtained. Based on the temperature characteristics of critical energy density, the measuring concept of dynamic focal spot of electron beam is put forward in the paper. The method of measuring dynamic focal spot of electron beam will provide a new possibility for 3D scanning prototyping through changing focus position of EB.
Design of LPDC Process for Thin-Walled Casting Based on Numerical Simulation
Authors: Zhang Li Qiang , Wang Rong Ji
Published: November 2012

The LPDC process parameters of A356 thin-walled aluminum alloy were designed based on numerical simulation by precisely setting the thermal boundary conditions. By applying the designed process parameters, a sound casting with 300mm in length, 100mm in width and 1.5mm in thickness was successfully prepared. The results indicate the numerical simulation technology is an effective tool for designing casting process and reducing the manufacturing cost.
Optimization Design for Laminated Composite Structure Based on Kriging Model
Authors: Zhu Wen Guo , Meng Zhi Jun , Huang Jun , He Wei
Published: November 2012

An effective optimization method is developed for laminated composite structures using two-level optimization strategy based on Kriging model and genetic algorithm (GA). Firstly, the design of experiment (DOE) technique is used to create sample points and MSC.Nastran is employed to obtain the response (minimum weight subjected to bulking and strength constraints) of each sample point. Based on sample points and the corresponding responses, the Kriging model is formulated. Secondly, GA is performed to obtain the best thickness by optimizing the Kriging model as objective function. Then, the best stacking sequence is obtained basing on lamination parameters using GA. This paper takes a Z shape composite stiffened plate as example to verify the feasibility of the method above. The results illustrate that it can significantly save computational costs and can greatly improve the optimization efficiency.
Study of Ageing Treatment on Spray Forming Al-Zn-Mg-Cu Alloy
Authors: Su Rui Ming , Qu Ying Dong , Li Run Xia , Li Rong De
Published: November 2012

The Al-Zn-Mg-Cu (7A04) alloys were prepared by using the method of spraying forming and the hot extrusion. The changes of microstructure and mechanical properties of the spray deposited Al-Zn-Mg-Cu alloy underwent ageing, regression and reageing treatment (RRA) was studied by scanning electron microscopy, X-ray diffraction and other methods. The results show that the tensile strength of the alloy aged at 120°C for 24 hours can reach the peak value (760MPa), but the elongation is only 4.8 percent. The toughness of the alloy regression treated at 160°C for 2 hours can increase to 9.0 percent, but its tensile strength decreases greatly (680MPa). The reaging treatment at 120°C can make the tensile strength up to 740MPa, while the elongation which is 8.2 percent still keeps a higher level.
Study on the Performance of Pearl Fiber Composite Yarn
Authors: Ma Hui Fang , Zhu Jin Zhong , Xin Hua Li , Liu Sen Lin
Published: November 2012

The strength and tensibility, elastic recovery ratio, evenness and hairiness of the pearl composite yarn were tested and compared with that of the same fineness pearl ring-spun yarn. It is concluded that the strength, elastic recovery and evenness of pearl composite yarn is superior to that of the ring- spun pearl yarn, thick spot or slub number per kilometer 1-8mm of hairiness index of pearl fiber composite yarn are lower than that of the pearl ring- spun yarn.
The Influence of Longitudinal Magnetic Field on DCEN MAG Welding
Authors: Wang Xu Ming , Zhang Wen , Wang Ying
Published: November 2012

This paper introduces the dynamic process of droplet transfer of DCEN MAG welding applied outside longitudinal magnetic field, and analyses the influence law of magnetic parameters on welding arc, droplet transfer behaviour, wire melting coefficient and weld formation. The feasibility of application of longitudinal magnetic field to DCEN MAG welding is established. We compared DCEN MAG welding with DCEP in order to further perfect rotating MAG welding.
Experimental Investigation of Mechanical Micro Machining for AL6061-T6 Material
Authors: Zhou Chun Jiang , Liu Jian Cheng , Avila Adrian
Published: November 2012

This paper is to experimentally investigate the mechanical micro machining properties of AL6061-T6 using tungsten-carbide micro end mills. The cutting simulation based on Finite Element Analysis (FEA) method is also conducted to estimate cutting forces, cutting temperature, and minimum chip thicknesses. The simulation results are used for the determination of experimental machining conditions such as depth of cut, feed rates and cutting speeds. A number of slot micro-milling experiments were performed using 400um diameter micro end mills on a 3 Axis CNC machining center attached with a high precision and high speed spindle unit. The machined surface quality, geometric feature shape, cutting burr generation as well as build-up edges are observed in the cutting experiments. Optimum cutting parameters for a better surface quality and smaller burr sizes are suggested.
Multi-Objective Optimization of the Loading Path in Tube Hydroforming Process Using NCGA
Authors: Zheng Zai Xiang , Xu Jing , Shen Hui
Published: November 2012

According to the limitations of conventional method of optimization design for the process parameters in the hydroforming process, a new simulation method has been proposed for the optimization of the process parameters, which is the integration of the neighborhood cultivation genetic algorithm (NCGA) and the dynamic explicit algorithm based on finite element method (FEM). The new method has been adopted for the optimization of the hydroforming loading path of an instrument panel beam and the process parameters are the internal pressure vs. time and the axial feeding displacement vs. time. It is concluded that the acquired loading path through the new method is more optimal than the one through the trial and error method. In addition, the new method can simultaneously generate multiple Pareto-optimum solutions in one computation and provide more freedom for the designer's decision making of the process parameters.
Comparsion of Foundry Properties of Traditional Foundry Sand and Microspheres
Authors: Shrivastava Vivek , Rao Sandeep , Dev Suhrid , Prashanth T.
Published: November 2012

A case study of the comparison of the properties of conventional foundry sand and light weight cenosphere/microsphere particles has been undertaken. This analysis was initiated by the preparation of their respective specimens, followed by the actual testing of these samples. Properties such as Compression strength, Shear strength, Permeability and Hardness were determined. In addition the grain form and microstructure of the specimens prepared was also analyzed. This analysis clearly indicates the possibility of the usage of cenospheres as a replacement of foundry sand.
The Influence of the Center-to-Center Distance on the Accuracy of the Serration with the New Gear Hob
Authors: Jin Ling Li , Ma Feng He , Peng Fu Hua
Published: November 2012

A gear meshing mathematical model was set up according to the tooth profile normal line method. The influence of the gear cutter-workpiece center distance on the tooth profile accuracy was discussed in spur gear cutting using a new type of gear cutter, with the center distance errors being ±0.005, ±0.01, ±0.02 and ±0.04 respectively. The results show that the machined tooth profile errors at the root circle is less than 1μm, while errors at other parts of the tooth profile are even smaller.
Transient Liquid Phase Bonding of Aluminum Using Aluminum Base Interlayer under Argon Flux
Authors: Li Xin Geng , Wang Xue Gang , Yan Feng Jie , Wang Hong , Wang Xiao Ming
Published: November 2012

An aluminum base interlayer was used for transient liquid phase bonding of pure aluminum under argon flux. The bonding was carried out at 595°C for 2 minutes under 7MPa. Microstructure of the joint was studied with SEM and EDX, and the mechanical properties were analyzed by tensile test and bending test. A homogenous bonding zone is observed in the joint. The defects in the joint are silicon oxides and voids. The tensile strength of the joint is 190MPa, and no failure occurs when the joint is bent to 180°. This indicates that TLP bonding can produce a strong and ductile Aluminum joint, which is equivalent to the base metal.
The Effect of Strain Field on Texture and Microstructure Evolution in Homogeneously Cold Rolled 93/7 Brass
Authors: Chen Yong Jin , Guo R. , Wan K. , Shi Q. , Duggan B.J.
Published: November 2012

In this study, SEM and Köhlhoff etching were employed to follow the rolling texture and microstructure development in 93/7 brass that had been homogeneously cold rolled to different plastic strains. Correlated with FEM to rolling process, the effect of strain field on rolling texture and microstructure development in rolled 93/7 brass is conducted and reasonable conclusion is obtained.
Effect of Die Angle on Electromagnetic Riveting Interference
Authors: Zhang Qi Liang , Cao Zeng Qiang , Chen Yun Quan
Published: November 2012

By establishing an axisymmetric finite element model of the electromagnetic riveting (EMR) joint, we studied the influence of riveting die angle on joint interference and the driven head. It was found that a decrease in the die angle leads to a decrease in the highest temprature in the adiabatic shearing band (ASB). An increase in interference and contact pressure between the rivet shank and apertue wall was also obeserved when decreasing the die angle, which has been proved to be benificial to the fatigue performance of the joint.
Influence of Surface Remelting Process on Corrosion Resistance of Welding Joints for SUS304 Stainless Steel by Electrode Arc Welding
Authors: Luo Hui , Yang Feng Qi , Liu Peng , Huo Yu Shuang
Published: November 2012

The electrochemical corrosion tests of SUS304 stainless steel joint which was welded by electrode arc welding show that. The welding energy has obviously effect upon corrosion resistance of welding joints. The welding current directly influences the corrosion resistance of heat affected zone (HAZ) of welding joint. The Surface of joints was remelted by the micro-plasma arc and argon arc process. It is suggested that corrosion resistance of welding joint was improved obviously after remelting. The main reasons for improving the corrosion resistance of welding joint may be that grain refined, chromium oxidation film formed and elements diffusion inhibited by arc-remelting process.
Study on Dynamics Performance of Nano-Concrete
Authors: Wang Kai Sen , Dai Ge Lin , Kong Fan Cheng , He Guo Liang
Published: November 2012

Based on static and dynamic compression tests of plain concrete, SiO2(NS) concrete, CaCO3(NC) concrete and composite concrete with different NS-NC contents, dynamics performance of nano-concrete materials is analyzed to study influence factors and find the optimum nano-content.
Stress Analysis and Failure Mechanism of H13 Steel Hot-Forging Die for Automobile Engine Crankshaft
Authors: Zhang Xiao Xun , Ma Chi Ying , Sun Yun Hua , Ma Fang
Published: November 2012

The hot forging process of automobile engine crankshaft was simulated in the present study on the basis of the finite element software DEFORM-3D. The materials of die and crankshaft workpiece are H13 steel and L1438 steel, respectively. The material flow in the die, contact pressure distribution and temperature distribution of the die were investigated. The interaction forces between the workpiece and the dies were mapped onto die faces to serve as load boundary conditions for die stress analysis. The results showed that the die stress reduces with increasing temperature and increases with increasing strain rate. Such behavior is likely associated with flow stress of the workpiece, which reduces with increasing temperature and increases with increasing strain rate. High flow stress results in high die stresses and hence more easily leads to die failure.
Key Technologies Research on Color Contour Map of 3D Injection Molding Simulation Results
Authors: Geng Tie , Ren Qing Hai , Tu Wei Qing , Liu Dan Dan
Published: November 2012

According to the color contour map of the 3D injection molding simulation results, the commonly used color contour map drawing algorithm was researched, and a three-dimensional color image rendering algorithm which based on the "physical field values and color range mapping" was given too. And the key technologies of the algorithm which was used to draw 3D color contour map were introduced in detail. In the end, an example was given.
Numerical Simulation of the Effect of Punch Paths on the Quality of Sheet Metal Stretch Forming
Authors: Wang Chang Jiang , Mynors Diane J , Sihra Tarsem
Published: November 2012

Presented here is the simulation of uniaxial stretch forming using two punches in a sheet metal forming operation. In the finite element modelling, the sheet metal strip was held by two bank holders and two punches are able to move in two directions to stretch the sheet metal. Due to the friction between the punch and sheet metal, it was found that friction affects the sheet metal forming quality, however by adopting an optimal punch path the effect of friction in sheet metal forming can be reduced. The effect of punch paths on the quality of the sheet metal are also reported in this paper.
Numerical Simulation on the Influence of Heated Mold Continuous Casting Process Parameters to Solid-Liquid Interface
Authors: Zhao Hong Jin , An Gui Huan , Zeng Wen Feng , Luo Xin
Published: November 2012

The effect of the position and shape of solid-liquid interface on process parameters has been studied by the numerical simulation method, and the reasonable process parameters have been given. The results shows that the position and shape of solid-liquid interface is mainly affected by mold temperature, casting speed and cooling distance. It were moved to the mold export with the improvement of the mold temperature, casting speed or the reduce of cooling capacity. And the reasonable process parameters are that the mold temperature is 1363-1373 K, casting speed is 80-100mm/min, cooling distance is 40-50mm. The research results would obtain stable operation conditions and improve the billet quality.
A Study of Hollow Jet on Spray Forming
Authors: Qu Ying Dong , Li Xiao Hong , Jiang Chong , Su Rui Ming , Li Rong De
Published: November 2012

In order to improve the atomization quality of spray forming, the cylindrical hollow jet technology was applied in the atomization process of spray forming, and a numerical simulation for the structure of hollow flow field in front of jet outlet was carried out, the distribution of hollow jet flow field was simulated under different inlet velocities and outflow technologies, and then the experimental verification was performed. The simulation results of single-phase flow field show that with increasing the liquid inlet velocity, the back flow are a can get enlarged, and the lower negative pressure can be generated, which is beneficial for the out flow of liquid metal. The simulation results of two-phase flow field show that the hollow jet can be produced a hollow part. The conclusion basically accords with the experimental result of water flow.
Analysis of Volumetric Shrinkage and Optimization of Process Parameters in Injection Molding
Authors: Chen Ji Ping , Ding Zhi Ping
Published: November 2012

Based on experimental method of factorial design, numerical simulation of injection molding using Moldflow software has been done. The effects of the gate number-distribution, melt temperature, packing pressure, packing time, injection time, etc. on volumetric shrinkage and the two-way interactions among factors in injection molding of plastic part have been researched. The regression model for volumetric shrinkage of plastic part has been obtained through multiple linear regression analysis of the experimental data. The optimization model has been established to optimize processing parameters setting leading factors which effect volumetric shrinkage as design variables and regression model of volumetric shrinkage as objective function. The volumetric shrinkage value of plastic part is less than the minimum volumetric shrinkage value of the main experiment, which indicates that the method has a good practical value in engineering.
Research on Tool Wear and Compensation Method of Ultrasonic Milling
Authors: Feng Dong Ju , Xu Zhan Guo
Published: November 2012

The phenomenon of tool wear and its generating reason and mechanism in ultrasonic milling are analyzed. Then, the effect of various process parameters on tool wear is researched. It is educed through analysis that compensation method of tool wear according to the path length of tool is more suitable for ultrasonic milling. The experimental results show that the mode of ultrasonic milling is completely feasible, and the compensation of tool longitudinal wear can be realized.
Influences of Blank Holding Force on Stamping of Large Ellipsoidal Heads Based on Simulation
Authors: Luo Zheng Zhi , Zeng Jing , Yu Jin Peng
Published: November 2012

Ellipsoidal heads is a important composition of railways tank car. Sheet stamping process is a common method used for manufacturing ellipsoidal heads. An accurate and efficient finite element model was developed for analysis and prediction of ellipsoidal heads forming quality, with different degrees of reduction deformation at different binder forces considered, and self-adaptive mesh were adopted to improve computational efficiency and quality. And the results of simulation was validated by experimental results. Based on this finite element model, the distributions of stress, strain and wall thickness during this process were obtained.
Investigation of High Cycle and Low Cycle Fatigue Interaction on Fatigue Behavior of Welded Joints
Authors: Wu Liang Chen , Wang Dong Po
Published: November 2012

Samples of Q345 steel welded joints were tested to failure under low cycle fatigue(LCF),high cycle fatigue(HCF) and combined fatigue(CCF) using an apparatus that is capable of providing interactive LCF/HCF loading. The stress ratio R is 0.5 and the frequency of HCF is about 19kHz. The result indicates that not only high frequency minor cycles superimposed on low frequency major cycles , but also low frequency minor cycles superimposed on high frequency major cycles can do remarkable damage to fatigue performance of welded joints. The CCF strength is characterized by amplitude envelope. If CCF fatigue life is characterized by LCF life, adverse effect of HCF component is underestimated. If CCF fatigue life is characterized by HCF life, adverse effect of LCF component is overrated.
Finite Element Analysis of Pharmaceutical Tablet Compaction
Authors: Si Guo Ning , Chen Lan
Published: November 2012

A finite element simulation of convex tablet compaction was present in this paper with Drucker–Prager Cap model of lactose material. The effects of different compression speed on tablet property were analysis. The results show that the maximum stress appears the top and bottom near the die and the mises stress distribution become more uniform with the speed decreased. The density distribution change little with the variation of compression speed and the maximum density locate the top and bottom near the die rim. The compression speeds have little affected on the powder displacement. The research can contribute to save cost for tablet production test through the simulation analyze the tablet property of compression process.
Study on Extending Tool Life of Micro WC Drills by Various Protective Coatings
Authors: Chao Choung Lii , Lin Wen Chung , Chou Wen Chen , Chen Ying Tung , Ma Kung Jeng , Chao Chung Woei
Published: November 2012

As the trend of electronic industry is fast moving towards miniaturization, diversity, high efficiency and high throughput, the devices to be mounted onto a PCB are increasingly densely packed so are the holes needed to keep all elements in place. To effectively and economically generate so many holes of small diameter and high aspect ratio, the drilling process has to be done in a high speed manner and tool life has to be kept as long as possible. This study aimed to improve the tool life and the quality of the obtained holes by applying various hard coatings on the drills. The results showed that tool life could be effectively improved from 2500 hits to around 11000 hits at 155Krpm and 3.5m/min when proper hard coating was applied. It was found that wear of drill was resulted mainly from abrasive wear and adhesion wear. It was also showed in the research that while non-coated drills suffered serious deformation after 500 hits those coated with Al2O3 could finish 11000 hits with very limited wear land on the drills.
An Optimization Design for Coefficient of Weld Reinforcement in Rapid Prototyping Based on Robotic Pulse MAG Forming
Authors: Huang Xue Wei , Bao Sun Ing , Wang Jing
Published: November 2012

During the process of rapid prototyping based on robotic pulse MAG forming, the coefficient of weld reinforcement is crucial to the geometric accuracy and mechanical property of metallic parts. The orthogonal design method, as well as the range analysis and variance analysis, were applied in this article to study the effects of wire feed rate, welding speed, pulse correction and arc length correction on coefficient of weld reinforcement, finding out the factors which were significant to the coefficient of weld reinforcement and optimizing the process parameters. The experimental results show that the order of the significance of parameters is as following: the welding speed, the arc length correction, the wire feed rate, and the pulse correction. Among them, the welding speed and arc length correction have the greatest influence on the coefficient of weld reinforcement, as is 0.025. The optimal process parameters are: arc length correction 8%, welding speed 14mm/s, wire feed rate 7.2m/min and pulse correction 0. At the same time, the coefficient of weld reinforcement is between 2.94 and 3.00, as the degree of confidence is 97.5%.
Study on Machining Characteristics of Ultrasonic Vibration Assisted Micro-EDM
Authors: Ichikawa Tomohiko , Natsu Wataru
Published: November 2012

The existence of debris in the inter-electrode area in micro-EDM interrupts the machining process. Applying ultrasonic vibration to the machining fluid helps circulate the machining fluid and remove the debris from the gap area, and thus reduce short-circuits and abnormal discharges. In this study, the effect of applying ultrasonic vibration to machining fluid in micro-EDM was experimentally investigated. It was found that a significant increase in the machining speed was realized by applying ultrasonic vibration. Also, with the vibration of the machining fluid, micro-hole drilling with ultra-small discharge energy became possible.
Study on Thinning of a Boron-Doped Polycrystalline Diamond Wheel-Tool by Micro Rotary W-EDM Approach
Authors: Chen Shun Tong , Chang Chih Hsien
Published: November 2012

This study presents a novel approach for using a micro rotary wire Electrical Discharge Machining (micro w-EDM) to thin the grinding-edge of a wheel-tool made from boron-doped polycrystalline composite diamond (PCD). For thinning the PCD, two discharge circuits (a Resistance-Capacitance (RC) circuit and a transistor) were used as power sources to obtain a grinding-edge of less than 10 µm in thickness and high surface quality. The wheel-blank is vertically mounted on a spindle and while rotating is thinned by micro w-EDM along a planned computer numerically controlled path. Experimental results verify that boron-doped PCD can be successfully thinned down to 5 µm in edge-thickness. The study shows it is possible to break (cut) diamonds of 10-µm grain size, leaving smooth surface-exposed diamonds at the cutting edge of the wheel tool. The dimensional and geometrical accuracy of the wheel-tool can be exactly controlled. Raman analysis reveals graphitizing of the PCD caused by local high temperature spark erosion at a peak of 1593 cm-1 in RC discharge circuit machining. The peak at 1332 cm-1 for the transistor circuit method indicates diamond sp3 structure. The surface degenerating layer produced by transistor circuit machining gives a suitably thin grinding edge with exposed diamond grains.
Experimental Study on Ultrasonic Grinding of Nano-ZrO2 Ceramics by Single-Grit
Authors: Zhao Ming Li , Zhao Bo
Published: November 2012

The ultrasonic-assisted single-grit grinding device is designed which can be used to efficiently simulate grinding process, and the comparative tests of single-grit ultrasonic grinding are carried out between Nano-ZrO2 ceramics and ZTA ceramics under different grinding depth. The experimental results show that the bigger the scratch depth was, the greater damage degree of material was, nano-ZrO2 ceramics’ grooves is smoother than that of ZTA ceramics and the damage of its material is minor; ultrasonic vibration broadens the range of plastic cutting of Nano-ZrO2 ceramics in some degree. The experimental phenomena also show that the rolling role of abrasive particle can be conducive to material plastic deformation.
Analysis of Main Optimization Techniques in Predicting Surface Roughness in Metal Cutting Processes
Authors: Rubio Eva María , Villeta María , Saá Adolfo J. , Carou Diego
Published: November 2012

This paper collects the main methodologies and tools employed for predicting the surface roughness. The goal of this work is to provide compact and adequate information that could be useful in metal cutting industries to select the techniques and optimization tools that best suit to their needs and particular requirements. Each approach, with its advantages and disadvantages, is outlined and the present and future trends are discussed. As result, a quick guide for using practitioners of mentioned industrial sector is provided in form of tables that relate: machining parameters, cutting tool properties, workpiece properties and cutting phenomena with the different techniques and optimization tools usually employed to analyze the different parameters and phenomena involved in the process of surface roughness generation.
Overviews of the Behavior of Heat Transfer of Soft-Contact Electromagnetic Continuous Casting Mold
Authors: Zhu Li Guang , Jia Xiang Ming , Wang Xing Juan , Li Zhi Hao
Published: November 2012

Abstract. Soft-contact electromagnetic continuous casting is a new technology to improve the surface quality of billet. The soft-contact electromagnetic continuous casting mold heat transfer mechanism was discussed through the molten steel heat transfer process in the mold in this paper. The aspect that previous studies have not designed in the heat transfer process has been pointed out in the last. The researchers did not add the flux film as a heat transfer medium,but the slag in the mold is a very important thermal resistance actually.