bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Gas Pocket Formation during Extrusion of Al Hollow Profiles and Establishing an Extrusion Seam Weld Limit Diagram
Authors: Khan Yawar Abbas , Torabzadeh Khorasani Sepinood , Valberg Henry Sigvart
Published: September 2011

In extrusion of aluminium alloys, using porthole dies, the billet metal is split into separate metal streams during flow into the ports. After that, the streams join by seam pressure welding in the weld chamber of the die and finally flow through the die exit emerging as the desired extrusion. Because of re-joining of the metal streams the extrusion will contain as many extrusion seam welds as there are bridges in the die. Dependent on the die design the metal will flow in such a way that a gas pocket may form behind the die bridge and remain stable here throughout the course of the extrusion process. If, at this stage of the process, the feed of metal into the region behind the bridge is increased the space behind the bridge may fill up completely and the gas pocket will disappear. In this work we have investigated how finite element modeling can be used (for a simple idealized case of 2-D extrusion welding) to understand the extrusion seam welding process, and to characterize what extrusion conditions will provide stable gas pocket formation behind a bridge, and when the pocket will disappear. The geometry of the welding chamber and the die opening was varied in a number of simulations to study this phenomenon using the FEM-code Deform 2D®. Based on these simulations we have been able to propose an “extrusion seam weld limit diagram (ESWLD)”. The ESWLD shows when extrusion will occur with a gas pocket present behind the bridge and when there is transfer to a state where the pocket disappears and the die fills up completely with metal. By curve-fitting the results can be presented by a mathematical model, i.e. by an equation allowing the reduction in extrusion at the point of transfer from a state of presence of the pocket to a state of complete die filling, to be computed from the dimensions of the porthole and the weld chamber, for a given billet size and a given bridge geometry. The model also shows which geometrical extrusion parameters of the die will favor complete filling of the space behind a die bridge instead of gas pocket formation there.
Investigation of Conclad Extrusion and Multi-Billet Extrusion
Authors: Hoshino Michihiko
Published: September 2011

In Nihon University, Conform continuous extrusion and new extrusion processes which are called multi-billet extrusion have been investigated last ten years. Conclad extrusion which was developed from Conform continuous extrusion[1], is applied to manufacturing trolley wire for train in Japan. The trolley wire which is copper covered steel wire has shorter life cycle than expected one because of corrosion for acid rain. The quality of welding part of copper must be improved. In this paper, it is investigated how to decrease involving oxide films in welding part by experimental method. On the other hand, the multi-billet extrusion[2] is applied to manufacturing automotive frames, especially impact attenuators. The developed extrusion process has been done under experimental condition. However, it is capable to vary geometries of rib which is in the inside of closed profile extruded products by this process.
Factors Influencing Bonding Mechanics in FSW of AA5754
Authors: Buffa Gianluca , Fratini Livan , Micari Fabrizio , Previte Giuseppe
Published: September 2011

Solid state bonding recurs in several manufacturing processes, as extrusion of hollow profiles and solid welding processes. Among the latter, Friction Stir Welding (FSW) is nowadays of particular industrial interest because of the specific advantages with respect to the classic welding technologies. Proper conditions of pressure, temperature, strain and strain rate are needed in order to get the final effective bonding. In the paper the authors compare different solid state bonding conditions obtained at the varying of the main process parameters in FSW of butt joints of AA5754 aluminum alloys. The experimental results are compared with the numerical ones from a FEM model previously developed by the authors, in order to investigate an effective bonding criterion to be implemented into the FSW numerical model.
Development and Application of Test Equipment for Torsion Strength of Non-Metal Materials
Authors: Ge Shan , Yin Yu Cheng , Liu Zhi Qiang
Published: September 2011

In order to determine the torsion strength of non-metal materials at ambient and high temperature, a kind of equipment with inductive heating, infrared thermometer and torque loading by mechanical electrical rider was development. This equipment has advantages such as quick heating, accurate temperature test and controlling, easy controlling and continues of torque loading and test atmosphere can be controlled. The torsion strength of fireclay bricks with sample size of 40 mm × 40 mm × 230 mm, were tested separately at room temperature, 800°C, 1000°C, 1100°C and 1200°C, using this equipment. Results indicated that for the same batch of samples, the torsion strength determined by this equipment has good consistency, and mean while, it was found that the torsion strength decreased with the increase of test temperature obviously. In additional, developed equipment could be used for the determination of torsion creep at high temperature, the highest temperature of fracture under certain torque during the heating process, torque cycle fatigue failure of materials and so on.
Investigation of Microstructure and Mechanical Property of the Fe3Al/Al2O3 Composites Fabricated by Mechanical Alloying Process and Hot-Pressing Process
Authors: Jiang Tao , Shi Xiao Ping
Published: September 2011

The Fe3Al/Al2O3composites were fabricated by hot-pressing process in this research. The Fe3Al intermetallics compounds powders were fabricated by mechanical alloying and heat treatment, then the Fe3Al powders and Al2O3powders were mixed and the Fe3Al/Al2O3composite powders were prepared, so the Fe3Al/Al2O3composites were fabricated by hot-pressing process at 1300°C for 2h under the pressure of 35MPa. The phase composition and microstructure of the Fe3Al intermetallics compounds powders produced by mechanical alloying and heat treatment were investigated. The phase composition, microstructure and mechanical properties of the Fe3Al/Al2O3composites sintered bulks were investigated. The XRD patterns results showed that there existed Fe3Al phase and Al2O3phase in the sintered composites. The Fe3Al/Al2O3composites sintered bulks exhibited the homogenous and compact microstructure, the Fe3Al particles were homogenously distributed in the Al2O3 matrix, the mean particles size of Fe3Al intermetallics compounds was about 3-4μm. The Fe3Al/Al2O3composites exhibited more homogenous and compact microstructure with the increase of Fe3Al content in the Al2O3matrix. The density and relative density of the Fe3Al/Al2O3composites increased gradually with the increase of Fe3Al content. The fracture strength and fracture toughness of the Fe3Al/Al2O3composites increased gradually with the increase of Fe3Al content. The elastic modulus and hardness (HRA) of the Fe3Al/Al2O3composites decreased gradually with the increase of Fe3Al content.
Comparison of the Low Temperature Degradation Properties of Two Y-TZP Ceramics for Dental Applications
Authors: Yi Yuan Fu , Wen Ning , Wang Xiao Ling , Shao Long Quan , Wang Chen
Published: September 2011

The purpose of this study was to investigate the influence of in vitro low-temperature degradation (LTD) treatments on the structural stability and mechanical properties of two commercial Y-TZP ceramics candidate for dental application. TZ-3YS and TZ-3YS-E powder were chosen because of there minor differences of chemical composition. The two powders were compacted at 200MPa using cold isostatic pressure, and densely sintered at 1500°C and 1450°C for 2hr respectively. Two methods of in vitro LTD treatments were performed, the first is to autoclave specimens in steam at 134°C, 2bar, for 1 to 5hr; the second is to immerse specimens into 4% acetic acid at 80°C for 168 hr. XRD was used to identify the crystal phases, flexural strength were tested according to ISO 6872 standard, surface microstructure was evaluated by Atomic Force Microscopy (AFM). Results show that the relative content of monoclinic phase was increasing with the prolonged aging time, the TZ-3YS was more sensitive to LTD compared with TZ-3YS-E. LTD tests did not necessary reduce the flexural strength of Y-TZP ceramics, the nucleation and growth of monoclinic phase were detected by AFM, and the surface microstructure induced by LTD was not identical between the two Y-TZP ceramics. AFM was a sensitive method to evaluate the transformation of Y-TZP ceramics. To choose appropriate Y-TZP powder for dental application, it is mandatory to examine the microstructure before and after LTD.
Microwave Sintering of SiCp/Al Composite
Authors: Chen Yu Hong , Ma Jian Jun , Guo Wen Jie , Jiang Liang , Yang Peng Yuan
Published: September 2011

Aluminum matrix composites reinforced by silicon carbide particles (SiCp/Al) were prepared using microwave sintering. The hardness, bending strength and compression strength of sintered composites had been measured. The results showed that SiCp/Al composite can be sintered by microwave in very short time. The oxidation or plating copper in silicon carbide surface can improve the mechanical properties of composites.
Study on Surface Characterization and Properties of Three Dimensional Nano-Porous Titanium Film
Authors: Ge Yong Mei , Ning Cheng Yun , Tan Guo Xin , Zheng Hua De , Li Dan
Published: September 2011

A Type of Three-Dimensional Nano-Porous Film on Titanium Was Successfully Prepared by Alkali Treatment. the Microstructure, Contact Angle and Surface Energy of the Film Were Investigated Using Scanning Electron Microscopy (SEM) and Contact Angle Meter. the Biomineralization of the Nano-Porous Titanium Was Studied in Vitro by Soaking in Simulated Body Fluid (SBF). the Experiment Results Demonstrated that Bone-Like Apatite Could Be Induced on Nano-Porous Titanium Surface, and the Apatite Crystals on Nano-Porous Titanium Surface Were Superior in Number and Higher in Crystallinity to that on Titanium Chemically Polished.
Ferroelectric Properties of Bi3.25Gd0.75Ti2.97V0.03O12
Authors: Huang Chong Qing , Chen M. , Mei X.A. , Sun Y.H. , Liu J.
Published: September 2011

Bi3.25Gd0.75Ti2.97V0.03O12(BGTV)ceramic were prepared by solid state reaction. These samples had polycrystalline Bi-layered perovskite structure without preferred orientation, and consisted of well developed plate-like grains with random orientation. BGTV caused a large shift of the Curie temperature ( TC) of Bi4Ti3O12(BIT) from 675°C to 398°C. The remanent polarization and the coercive field of the BGTV were 30μC/cm2and 52kV/cm at an electric field of 87kV/cm, respectively. Furthermore, the dielectric permittivity and dissipation factor were 300 and 0.003 at 1MHz, at 1V and at room temperature, respectively. These ferroelectric properties of BGTV are superior to V-doped Bi4Ti3O12(~20μC/cm2and 80kV/cm) and (Sr, Ta)-doped Bi4Ti3O12(~12μC/cm2and 71kV/cm) ceramics. In addition, the dense ceramics of BGTV could be obtained by sintering at temperatures 100─200°C lower than those of the SrBi2Ta2O9system.
Electrical Behaviors of Bi2WTi3O12 Ceramics
Authors: Huang Chong Qing , Chen M. , Mei X.A. , Sun Y.H. , Liu J.
Published: September 2011

Bi2WTi3O12ceramics are fabricated by conventional solid-state reaction process. XRD analysis reveals that Bi2WO6is the main phase and Bi4Ti3O12is the second phase. With increasing temperature the sample first appears metallic behavior, then strong electrical fluctuations above 100°C, and finally exhibits stable nonlinear properties characterized by semiconductivity above 300°C at low field (E ≤ 100V/mm). The Arrhenius law for electrical conductivity by thermal activation is not suitable to explain the anomalous results. Based on the phase transition of tungsten trioxide from room temperature to about 300°C, the electrical properties of Bi2WTi3O12ceramics can be explained.
Analysis and Experimental Study on Magnetic Fluid Seal Mechanism
Authors: Zhang Hai Na , Li De Cai
Published: September 2011

The authors put forward a new design of experimental setup in order to study the mechanism of magnetic fluid seal, and used Ansys to simulate the magnetic field distribution in the setup, the results prove its rationality. The experiment to study the way of pressure transmission has been done on the experimental setup. The experimental conclusion shows that pressure transmission is based on the recoverability of the magnetic fluid seal. When pressure exceeds the ability of the seal stage, there is a leak path in the magnetic fluid, and then the gas flows to the next stage, after that, the leak path disappears. Pressure transmits from one seal stage to the next one in this way.
Solvothermal Synthesis and Characterization of Two Iron Complexes
Authors: Hu Ya Wei , Ma Yang Min
Published: September 2011

Two iron complexes, Fe3(dtdb)2(HCO2)2(DMF)2(H2O)2(1) and Fe(bpy)(Hdtdb)(H2O) (2) were solvothermally synthesized and characterized by single crystal X-ray diffraction. Fe3(dtdb)2(HCO2)2(DMF)2(H2O)2 (1) shows 2D layer structure crystallized in a triclinic with space group P-1 and cell parameters, a = 8.5591(10) nm, b = 11.2502(13) nm, c = 11.4370(14) nm, α = 90.687(2)º, β = 110.275(2)º , γ = 90.712(2)º, and Z = 1. Fe(bpy)(Hdtdb)(H2O) (2) shows surper- molecular architecture crystallized in a triclinic with space group P-1 and cell parameters, a = 8.286(12) nm, b = 11.5937(16) nm, c = 11.8477(17) nm, α = 93.932(3)º, β = 102.442(3)º, γ = 97.117(3)º, and Z = 1.
Testing and Evaluating Method of Dispersion of Carbon Nanotubes
Authors: Liu Xiao Yan , Liu Lei , Wei Feng , Jin Dan
Published: September 2011

The dispersion of carbon nanotubes (CNT) will directly influence the performance of CNT-cement composite. In this article, different surface-active agents were tried in dispersing the CNT in the water. Through standing and centrifugal treatment, the dispersion of CNT in the water was evaluated. The CNT was also mixed with cement. By testing the resistivity of CNT-cement composite, the dispersion of CNT was studied and evaluated. The results showed that standing, centrifugal treatment and measuring the resistivity were all effective ways in testing and evaluating the dispersion of CNT.
Evaluating Impact Properties of Cement Clinker at Different Angle for Impact Indentation
Authors: Wang Xiu Fang , Bao Yi Wang , Qiu Yan , Liu Xiao Gen , Tian Yuan
Published: September 2011

Spherical impact indentation tests with different impact angles (90°, 60°, 45°, and 30°) was carried out to understand the effect of impact angles on damage degree of cement clinker. A linear rail which can adjust angle to alter impact velocity was used to guide the slipping impact head to impact the sample. The different steel wedge was used to change the impact angle. It is found that the area of damage surface for cement clinker is most serious the peak impact force for surface damage decreases but the contact indentation becomes longer with decreasing impact angle when the impact angle is 45°. Under almost the same impact velocity, the smaller the impact angle, the higher the impulse, the longer contact time, and the peak impact force of 45° is maximum.
Study on the Glassy Phase Composition of 95 Al2O3 Ceramics
Authors: Chen Yin Juan , Li Qiang , Jiang Dan Yu
Published: September 2011

The glassy phase in alumina ceramics is implied for Al2O3-SiO2-CaO. The content of Al2O3 and CaO can be measured by the common titration method for their total dissolution in 5% HNO3 and that of SiO2 can be measured by gravimetric method. Therefore, the glassy phase composition in alumina ceramics can be analysed. The content of each component is measured exactly by both powder method and sheet method.
Microstructure, Mineral Phases and Strength of the Foam Concrete
Authors: Yu Xin Gang , Luo Shi Song , Gao Yan Na , Xiao Huaan , Li De Jun , Xu Hong Chao , Li Fang
Published: September 2011

The relationship among the composition, microstructure and strength of materials is always one of the hotspots for scholars of materials research. The influence of curing time on the compressive strength and flexural strength of the foam concrete with the cement, cement-slag and cement-steel slag as main binder respectively was studied in this paper. The microstructure of these foam concrete was analyzed by SEM and the mineral phases of the foam concrete was analyzed by XRD. The relationship among the binders, microstructure, mineral phases and strength of the foam concrete were explored and the reasons of why the strength of the cement foam concrete and cement-slag foam concrete is much higher than that of the cement-steel slag foam concrete are proposed.
Biological Safety Assessment of a Colored Zirconia Ceramic: Hemolysis and Short-Term Systemic Toxicity Tests
Authors: Lu Huai Xiu , Deng Bin , Shao Long Quan , Yi Yuan Fu , Liu Jie , Zhang Wei Wei , Wen Ning
Published: September 2011

Objective: To evaluate the biological safety of a colored zirconia ceramic regarding its hemolytic activity and short-term systemic toxicity. Methods: Fresh anti-coagulating rabbit blood was mixed with test materials and the hemolytic activities detected spectrophotometrically. Suspensions of the ceramic were fed to rats for one week while monitoring food consumption and relative growth rate and with subsequent pathology examinations of vital organs and tissues. Results: The hemolytic activity of the ceramics was <5%, and rats in all groups showed weekly relative growth rates of food utilization and body weight with no statistically significant differences. There were also no pathological changes observed among the various examined organs between the experimental and control groups. Conclusions: This colored ceramic showed good biocompatibility in terms of hemolytic activity and short-term systemic toxicity.
The Prospective Analysis of Listed Ceramic Companies in China
Authors: Hua Rong Hui , Shen Bing , Liu Yu Ling
Published: September 2011

Chinese listed ceramic companies grow slowly these years. They cannot compete with world-famous companies in the international market. Using SWOT method for analysis, we see the opportunity of the industry lies in the huge inner and outer market space. While the main weakness points are short of innovation and technical personnel. The threats are the changed market conditions and the strength lies in the production capacity. In the end, we put forward two suggestion, they are setting up holistic ceramic industry and stimulating inner and outer sales through detailed market segments.
Stress-Sensitive Property of Carbon Fiber Reinforced Cement under Cyclic Load
Authors: Liu Xiao Yan , Wang Xin Rui , Liu Ai Hua , Zuo Jun Qing , Feng Wei
Published: September 2011

In this paper, changes of resistivity of carbon fiber reinforced cement (CFRC) under cyclic load at different stress levels (15%, 35% and 55% of the failure stress) were studied. Experimental results showed that resistivity decreased with the increasing stress and increased with the decreasing stress under cyclic compression load. The resistivity of CFRC was reversible and cyclic under cyclic load at low stress level. When stress increased to a certain value, the decreasing rate of resistivity with increasing stress slowed down. When stress increased further, CFRC specimen resistivity cannot return to the initial value, showing a certain irreversible behavior. The feasibility of CFRC used in testing concrete fatigue was also discussed based on the conducting mechanism of CFRC.
Effect of Temperature on the Interfacial Bonding Strength between PVB and Glass from RT to -50 °C
Authors: Tian Yuan , Bao Yi Wang , Wan De Tian , Wang Xiu Fang , Han Zhi Ming
Published: September 2011

Laminated glass and photovoltaic laminated glass are widely used in architecture. The interfacial bonding strengths between poly(vinyl butyral) (PVB) and glass were investigated by the cross-bonding method from room temperature to -50 °C. The loading speed was 5 mm/min, and the cooling speed was about 0.5 °C/min. The testing sample was hold at each temperature for half an hour. It was revealed that the testing temperature had great effect on the bonding strength. At room temperature, the tensile bonding strength was 11.49 MPa and the shear bonding strength was 6.61 MPa. With the temperature decreased from RT to -50 °C, the tensile bonding strength was decreased by 66.81%, but the shear bonding strength was increased by 212.16%. From RT to -30 °C, the change rates of the tensile and shear bonding strength bonding strength were 65.57% and 172.68% respectively, only 3.61% and 14.48% from -30 °C to -50 °C. The mechanism for the bonding strength depended on testing temperatures from RT to -50 °C was also discussed.
Evaluating Erosion of Engineering Materials Subject to Cavitation in Liquids on a Ultrasonic Vibratory Apparatus
Authors: Han Jie Sheng , Chen Yuan Ping , Li Zhen , Chen Zu Jun , Lu Jin Jun
Published: September 2011

To evaluate the erosion of various engineering materials subject to cavitation in laboratory, a ultrasonic vibratory apparatus (UVA-1) is designed and manufactured according to ASTM G 32-06. The principle and setup of the UVA-1 are briefed. Some utilities of this apparatus are listed with several good examples.
Identification of Material Constitutive Parameters Using Orthogonal Cutting Tests and Genetic Algorithm
Authors: Lan B. , Feng Ping Fa , Wu Zhi Jun
Published: September 2011

Identification of workpiece material constitutive parameters for their application in the simulation of metal cutting process has been a hot research spot for long. This paper proposes a methodology to address this problem using orthogonal cutting tests and Genetic Algorithm (GA). First, an analytical model which calculates the dynamic characteristics occurring in the primary shear zone is introduced; then, orthogonal cutting tests are carried out, to record the following mechanical characteristics with the analytical model: shear stresses, shear strains, strain rates, cutting temperatures; afterwards, GA is employed to obtain the constitutive parameters from these characteristics; at last, the finite element method (FEM) simulations of the cutting tests are performed to evaluate the predictive accuracies of the obtained parameters. In this paper, a Japanese brand steel SCM440H is used as the workpiece material, and the simulation results of its constitutive parameters show good agreements with the experimental data, which renders the feasibility of the proposed methodology.
Study on Kaiser Effect of Edge Chipping for Engineering Ceramics during their Failure Process
Authors: Tang Xiu Jian , Tian Xin Li , Wu Zhi Yuan , Zhang Bao Guo , Wang Jian Quan
Published: September 2011

An edge chipping experiment under static load is adopted to study the Kaiser Effect during the failure process for engineering ceramics. The mechanisms inducing Kaiser Effect are discussed. Some AE signals during the course of Kaiser Effect are analyzed. The results show that there’s obvious Kaiser Effect during the failure process of edge chipping; count, energy and amplitude can be well used to describe the Kaiser Effect. The surface metamorphic layer remained on the ceramic surface during the course of machining is the main factor for Kaiser Effect. Edge distance and mechanics characteristic are the important factors for Kaiser Effect. The study on Kaiser Effect of edge chipping has provided some guidance to prevent edge chipping of engineering ceramics.
Research on Cutting Cast Super Alloy K24 with Milling and Abrasive Water Jet Methods
Authors: Wan Yi , Liu Zhan Qiang , Zhu Hong Tao , Ai Xing
Published: September 2011

A difficult-to-machining material, cast supper alloy K24 has been cut with two different methods, milling and abrasive waterjet (AWJ). It is shown that milling is characterized by high tool cost, low efficiency, and good surface roughness while abrasive waterjet brings high efficiency and worse surface quality. The results have proven that the combination use of AWJ and milling is an efficient way in cutting K24.
Cutting Temperature Investigation when High-Speed Milling of SiCP/Al Composites
Authors: Ge Ying Fei , Xu Jiu Hua , Fu Yu Can
Published: September 2011

High-speed milling tests were performed on SiCp/2009Al composites in the speed range of 600-1200m/min using PCD tools to investigate the cutting temperatures and the influence factors. The results showed that the cutting temperature could reach 580°C under the given cutting conditions. Graphitization took place on the PCD tools under the high cutting temperature coupled with the effects of abrasive wear of SiC particles and catalysis of copper in the 2009 aluminum matrix. Cutting parameters, tool materials, workpiece materials and tool wear condition had significant effect on the high speed milling temperature while tool geometries had the minor effect. Among these influence factors, cutting speed was the most significant factor. Reinforcement volume fraction was the less significant factor and followed by radial depth of cut, feed rate and tool materials.
An Explicit Integration Algorithm for Introducing User-Defined Thermo-Viscoplastic Constitutive Models in FE Simulations
Authors: Gao Chong Yang , Liu P.H. , Zhang Liang Chi
Published: September 2011

Material models in the libraries of commercially available finite element codes often cannot satisfy the needs of some special material property descriptions, such as those of materials under ultra-high-speed cutting. To overcome the difficulty, this paper introduces an efficient explicit algorithm to implement a generalized user-defined model of metal plasticity into the Abaqus/Explicit program. This algorithm makes the computation quite efficient by avoiding updating the tensor of elastic-plastic modulus in each increment.
Effect of Cutting Speed on Surface Integrity in High Speed Machining Nickel-Based Superalloy Inconel 718
Authors: Liu Zhan Qiang , Cao Cheng Ming , Du J. , Shi Zhen Yu
Published: September 2011

Surface integrity is becoming important to satisfy the increasing requirements service life of machined parts. The purpose of this study is to investigate the effects of cutting speeds on surface integrity of Inconel 718. Experiments are conducted on a CNC machining center under various cutting speeds. The machined surface integrity is evaluated in terms of surface roughness, microhardness and residual stress. Experimental results show that machined surface integrity of Inconel 718 is sensitivity to the variations of cutting speeds. The surface roughness firstly increases with the cutting speeds increasing at the range from 50 m/min to 200 m/min, then decreases with the further increasing of the cutting speeds. For microhardness, it can be seen that work-hardening for the machined surface is serious. The surface residual stresses are tensile ones at the range of the selected cutting speeds from 50 m/min to 3,000 m/min in this research.
The Research on Milling Forces of Dry Cutting Spiral Bevel Gears
Authors: Li Qing , Liao C.J. , Wang Run
Published: September 2011

Based on the high-speed cutting theory, high-speed dry milling processes of spiral bevel gears are studied and mathematical models of milling forces are established in this paper. This paper analyzes variation trend of high-speed cutting force and puts forward the notion of non-constant feed cutting according to specific cutting process, so that the purpose of lowing the maximum main cutting force and reducing the fluctuation of cutting force can be achieved.
Evaluation Modeling and Optimal Adjustment of Position Error Based on Localization Sensitivity Analysis
Authors: He G.Y. , Hu C.X. , Liu X.
Published: September 2011

Sensitivity analysis is to evaluate how sensitive the surface deviation of a workpiece is to a geometric error of locator. With this thinking, the relationship between geometric error of locators and the position error of holes group is presented. The fixture system errors model and evaluation model of position errors are established. Furthermore with both models, a method of optimizing the position errors by adjusting the locators’ position is presented, which can get to accuracy localization. At last, a simulation study is used to verify the method.
The Formation Laws and Influencing Factors of Strengthening Layer in EDM of Stainless Steel 1Cr13
Authors: Wang Hong Xiang , Zhang X. , Gao S. , Tang Y.B.
Published: September 2011

For the abrasion phenomenon of the turbine flowing-passage components was very serious, the electrical discharge machining (EDM) surface strengthening process of stainless steel 1Cr13 by different electrodes were carried out in this paper, the formation laws and influencing factors of the EDM surface strengthening layer are researched deeply. The correspondence relation between strengthening layer thickness and enhancing time, electrode materials, and electrical parameters are obtained by the detailed theoretical analysis and experimental investigation. The results show that, in the premise of the strengthening layer thickness, workpiece quality and machining efficiency, the strengthening process can be improved by reasonable selecting and controlling the process parameters such as discharge voltage, capacitance, pulse frequency, peak current, pulse width and enhancing time.
Numerical Analysis of Surface Temperature in Grind-Hardening Based on Time Variation Heat Flux
Authors: Zhang Yu , Ge Pei Qi , Zhang Lei
Published: September 2011

The invariable heat flux is always loaded in temperature simulation for grind-hardening. The heat flux is time-variant in actual process. The paper uses experiment result of grinding force to calculate out the time variation heat flux. The grinding temperature is simulated based on time variation heat flux by ANSYS software. The variation tendencies for the grinding force and the simulated surface top temperature will be discussed.
Qualitative Analysis and Study the Workpiece Shearing Surface Quality of Fine-Blanking with Negative Clearance
Authors: Du Hong , Zhang Zhong Mei
Published: September 2011

The workpieces of fine blanking with negative clearance were obtained through the fine-blanking with negative clearance processing experiment. The fractography photographs of workpieces shearing surface were scanned by scanning electron microscope (SEM), and the characterization parameters and quality standard of workpieces shearing surface with negative clearance were analyzed in the processing of blanking. According to the characterization parameters and quality standard of workpieces shearing surface with negative clearance, the workpiece with the length ratio of burnish band, deflection error, rollover error and blanking burr were analyzed qualitative. The findings have a certain reference value to the blanking related profession.
Wear and Friction Properties of TiN,TiAlN and CrAlN PVD Coatings
Authors: Liu Ai Hua , Deng Jian Xin , Zhang Hui , Lian Yun Song , Zhao Jun
Published: September 2011

The paper reports a comparative study of the tribological properties of the most employed hard coatings like TiN, TiAlN and CrAlN. Ball-on-disc wear tests were performed on the CETR UMT-2 test system against Si3N4balls with a relatively high speed of 100m/min. The coating character and test results were obtained through SEM, XRD and Wyko surface profilometer. The results are as follows: The friction coefficients of the three coatings are relatively high because of the superabundant wear debris during tests. The wear behaviour and wear tracks exist distinct differences for different coatings. As for wear rates, the sequence of three coatings is TiN>TiAlN>CrAlN, the combination property of CrAlN is the best.
Design of Balance Control Mechanism of Nitriding Layer Depth in Ion Nitriding
Authors: Ma Lian Jie , Sun M. , Gong Ya Dong
Published: September 2011

Through design of balancing movement controller of large size workpiece for applying to LDMC-100 type ion nitriding furnace, the structure and principle of mechanism were introduced, the balance of mechanical transmission and influencing to nitriding layer of workpiece surface were analysed. In this mechanism, the planetary gear system was adopted, the single axis was adopted in this supporting mechanism, and the electric and insulating on workpieces were used. The balancing influencing of movement and techniques parameters for nitriding layer were discussed. The results indicate, the nitriding period is related with input speed and number of driven gear teeth. The re-nitriding rate and blank nitriding rate are related with gear modulus, workpiece outside diameter, number of drive and driven gear teeth. When the mechanism structure parameter is fixed, the effect of nitriding was completed by changing speed of input axis.
Defect Detection Study of Fabric Based on Gabor Filter Algorithm
Authors: Li G.X. , Li Y.F.
Published: September 2011

This thesis exploits a multichannel Gabor filters detection algorithm. Analysis filtering images from different orientations and scales, then fuses the multichannel data. Finally, a threshold iterative algorithm and mathematical morphology post-processing is used to achieve the fabric defect detection. The experiment selects five types of fabric defect image. Experimental results suggest that this algorithm can effectively identify blob-shaped, linear and planar defect and has well real-time character.
Research on Shape Detecting System of Cold Rolling Strip
Authors: Yang Li Po , Yu Bing Qiang
Published: September 2011

Comprehensive considered actual working conditions of cold rolling mill, a high precision shape detecting system of cold rolling strip was developed to meet industrial application. Consideration to both follow-up processing technology requirements, dynamic flatness standard curves could be formulated according to different rolling conditions and product specifications, and reliable shape datum were provided for close-loop shape control. This system was successfully used in Angang 1250 mm HC 6-high reversible cold rolling mill. Then the shape index and the quality stability of cold rolling strip were increased significantly, the errors between the calculated values and measured values of the total tension were less than 3%, the precision of shape detecting is 0.2 I and shape indices was within 6 I after the close-loop shape control was input.
Study on Key Technologies of Aero-Engine AMRO Support System
Authors: Sun H.B. , Chang Zhi Yong , Wan N. , Mo Rong
Published: September 2011

In order to solve the digitalized management problem of aero-engine in the whole lifecycle, a framework of aero-engine AMRO supporting system is put forward. Management of assembly, maintenance, repair and overhaul are involved. Modeling and integration of aero-engine status data, assembly process management, on-spot operation guide, online education support, integration and synchronization of data and fault diagnosis support are regarded as key enabling technologies and studied deeply. Correspondent solutions are given respectively. The assembly digitalization sub-system and the IETM sub-system are developed to validate the proposed system. And close-loop controlling of single aero-engine information is achieved, and the study provides technology support for improving level of aero-engine status digitalized management.
Analysis of Physical Condition of Aero-Engines Based on Flight Data
Authors: Li Y.Y. , Tan G.Y. , Cheng Y.L. , Cheng F.C.
Published: September 2011

Through the analysis of typical aero-engine fault, the function parameters under different throttle openings of the aero-engine are presented, and the fault characteristic learning as the training set are studied using the RBF neural network. An aero-engine function evaluation model is proposed in this work by comparing the test set with the expected value of the training set, and the decay degree of engine function are determined. The proposed method is validated to be an effective method of diagnosing and identifying the aero-engine fault accurately and timely by testing large amount of recorded flight data from each of various types of aero-engines. It makes it possible for early and successful diagnosis and prediction of the health condition of aero-engines.
Microstructure Design with Multiphase Materials under Mass Constraints
Authors: Qiu Ke Peng , Zhang Wei Hong , Gao T.
Published: September 2011

The microstructure design satisfying the mass constraint can reduce the structure weight more directly and effectively in comparison with the volume constraint. This paper is devoted to the topology optimization of microstructures with multiphase materials under the mass upper limitation constraint for maximizing the equivalent elastic tensors and their combinations. Firstly, the strain energy method is applied to compute the effective elastic properties of microstructures. In order to make sure that the formulation of mass constraint is linear with separable design variables, DMO (Discrete Material Optimization) model is adopted for the element density interpolation. Therefore, this optimization problem can be solved efficiently by means of mathematical programming approaches, especially the convex programming methods. Besides, the filtering technique is adopted to avoid the checkerboard pattern. There are two categories of numerical examples. In the first category, the modulus and the stiffness ratio of the solid material phase 1 are smaller than the solid material phase 2. In the second category, the modulus of the solid material phase 1 is still smaller than the solid material phase 2, but its stiffness ratio is bigger than the solid material phase 2.
The Topology Optimization Design for the Stereolithography Based Investment Casting Pattern
Authors: Gu X.J. , Zhu Ji Hong , Zhang W.H. , Li J.S.
Published: September 2011

The purpose of this paper is to introduce the topology optimization method into the lattice style design for the rapid casting SL patterns. During the burnout procedure of the SL resin pattern, the thermal expansion will lead to the crack of the ceramic shell and fail the investment casting. Therefore, the SL patterns are always designed hollowed and some lattice styles are used to fill the cavity to solve the problem. In this paper, we propose to carry out the structural design by assigning the inner part of the SL pattern as the design domain where the material distribution is optimized with topology optimization. The idea is 1) to save the cost of the resin material, 2) to solve the crack problem of the ceramic shell and 3) to maintain certain stiffness for the pattern itself. As a result, we choose to minimize the thermal stress in the ceramic shell as the design objective with the stiffness and material cost of the SL pattern constrained to certain values. The topology optimization is implemented with different definitions of design domain in this paper. Various optimal results are obtained numerically. By comparing the optimal design with the existing lattice style, the newly obtained designs have shown better performances in reducing the stress in ceramic shell and maintaining the stiffness of the SL pattern.
Optimal Design of Aero-Engine Stator Structure with Combined Shape and Topology Optimization Method
Authors: Yang Jun Gang , Zhang W.H. , Zhu Ji Hong
Published: September 2011

In this paper, the lightweight design of an aero-engine stator structure is studied as an application case. Different kinds of loading conditions are taken into account. Mathematical formulations of the optimization problem are presented. Two optimization strategies combining shape and topology optimization are tested to get optimal design results.
FEM Analysis of Large H-Beam in Rough Rolling Process
Authors: Dong B.T. , Zhang Qin He , Li Chuan Yu , Ma Ru Po
Published: September 2011

The Standard and Explicit solver of ABAQUS were synthetically used to establish finite element model for reciprocating multi-pass rough rolling of large H-beam, in which the re-meshing technique was utilized to solve the problem of excessive deformation and rollers’ deformation were taken into simulation to increase the accuracy. Based on the simulation results, stress field, thermal field and deformation behavior of the workpiece were discussed. It clearly showed that the main deformation of profiled blank in rough rolling was web broadening. Compare the analytical rolling force results to the practical rolling process, and this method could provide some valuable references to the rolling practice.
Topology Tailoring Method of TWB Autobody Parts Based on HyperWorks
Authors: Xu An Ping , Liu Y.S. , Wang H. , Liu Y. , Fu Y.N.
Published: September 2011

In the paper, a lightweight design method for tailor-welded blanks (TWBs), termed as Topology Tailoring Method (TTM), is proposed, which is based on topology optimization philosophy and in which the variable density method is employed so as to reach the goal of the smallest structure strain energy. By using this method, a TWB autodoor subjected to a specific working condition is topologically optimized in HyperWorks, thus obtaining the more lightweight autodoor. At last, a side impact simulation of the autodoor is demonstrated, thus showing the effectiveness of the method.
The Design and Optimization of Large-Scales Heavy Gantry NC Machining Center Based on Finite Element Method
Authors: Xu Shu Bo , Sun K.K. , Jing Cai Nian , Ren Guo Cheng
Published: September 2011

Large gantry machining center can be applied to large diameter and thickness of the flanges, tube sheets and other large sheet metal processing, the industrialization of this type of device for improving the development of modern processing and manufacturing of great strategic significance. The design and optimization of large-scales heavy gantry CNC Machining Center was mainly investigated in this paper. The finite element model of the beam structure was structured by using finite element analysis software-ANSYS. On the basis of analysis results, the optimal static and dynamic performance of square cross-section of the beam structure has been obtained. The maximal displacement is 0.531 mm. The maximum displacement of X=0.0329mm, and Y=0.531 mm occurred in the contact point of middle beam and spindle box. Z is 0.0948mm. The maximal displacement of Y-component is occurred in the contact points of guide and spindle box. This may have a certain impact on the machine processing accuracy. In the middle of the beam can consider to strengthen its internal structure, such as adding reinforcement measures to further improve its rigidity, and improve the machining precision of the whole machine.
Crashworthiness Analysis of Mobile Hard Disk under Different Drop Angles
Authors: Yang Shu Yi , Liu D.S. , Zhao Ji Yun , Li H.
Published: September 2011

Mobile hard disk is very sensitive to vibration because of unique mechanical working and the complexity of components. In view of inner structure and complying with quality equivalent principle, a 2.5 inch mobile hard disk finite element model is established based on ANSYS/LS-DYNA. The crashworthiness evaluate index is analyzed and set forward. The influence of drop angle is analyzed through simulation. In theoretically, the results are proven to be fundamental method of crashworthiness analysis, evaluation and design for mobile hard disk.
Gyroscopic Torque Analysis and Dynamic Balance Test of the Vertical Aerostatic Spindle
Authors: Zhang Fei Hu , Fu Peng Qiang , An C.H. , Sun Jiu Wei , Wang Sheng Fei
Published: September 2011

Ultra-precision flying cutting machining with a vertical milling style is an important means of ultra-precision machining. It has a close relationship between the machining accuracy and the dynamic characteristics of the aerostatic spindle. The film force acting on the spindle rotor is related to the manufacture, installation and static unbalance or dynamic imbalance or other factors. Therefore, it is necessary to analyze the dynamic pressure force caused by these factors in order to study on the rotor posture and quantitative movement of the spindle. This article derived the solution formula for the dynamic pressure reaction force of the ultra-precision machine tool spindle with vertical static film based on the basic theory of the rigid body dynamics. The gyroscopic torque of the spindle has been analyzed under different conditions with the spindle dynamic balancing tests, which provide a reference to the further analysis of the spindle dynamic characteristics.
Optimization Design of the Wind Turbine Gearbox Based on Genetic Algorithm Method
Authors: Li Ya Feng , Xu Y.X. , Li G.X.
Published: September 2011

According to the performance requirements of three-stage wind turbine gear box, the mathematical model was established as object function. Design of the gear box was optimized with genetic algorithm and the examples showed that design of the gear based on genetic algorithm can gain more optimized result. The method is a supplementary to reliability optimization methods for Wind turbine gear box.
Finite Element Analysis of Crawler Frame of the Rotary Drill Bits
Authors: Sun Y. , Yang Y.Q.
Published: September 2011

Commercial finite element modeling software ANSYS was used to calculate the stress and deformation distributions of crawler frame of the Rotary drill bits under turning work condition. By using finite element method, the weak points of the crawler frame can be found and the strength of the model can be calculated quickly and correctly. The results show that the crawler frame has enough strength to support the machine to finish the turning process and the maximum displacement distributed in the middle of the crawler frame. This paper will supply references for the structural optimize design of crawler frame of the rotary drill bits.
Strength Analysis and Optimal Design of a Movable Power Station Package
Authors: He B.Y. , Chen S. Z.
Published: September 2011

Movable power station is an emergency power supply (EPS) equipment. It consists mainly of a diesel generator and a noise reduction package. The noise reduction package has been designed by empirical methods traditionally, which usually leads to underdesign or overdesign. This paper aims to investigate the strength, stiffness and frequency characteristics of the package by finite element method, thus structural optimization scheme of the package is further obtained. The optimum package proved to be in good performance compared with the original structure.
Reliability Design of Car Suspension Coil Spring Based on Maximum Entropy Method
Authors: Liu Chun Zhe
Published: September 2011

A practical and effective numerical method of reliability design with arbitrary distribution parameters is proposed in the paper. And techniques from the maximum entropy method, the reliability design theory and probabilistic engineering design are employed to present an approach for the reliability design with arbitrary distribution parameters. Therefore maximizing the entropy of the state equation distribution should lead to the least biased estimate of its form, which helps us analyze the reliability design of automobile components from an elementarily.