bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the Flexural Behavior of SMP Sandwich Beam
Authors: Li Zheng Fa , Wang Zheng Dao
Published: August 2010

Shape memory polymers (SMPs) can have a large frozen strain but providing much lower recovery stresses. To overcome such disadvantage, sandwich structures consisted of a SMP core and two thin metallic skins was considered. Due to much compliance of the SMP core, SMP sandwich beam is buckled at a lower packaging strain. Buckling is the fundamental character of SMP sandwich beam under bending. The critical buckling parameters about two types of SMP sandwich beams were theoretically derived.
Dimeric Liquid Crystalline Epoxy Resins Containing Azo Group: Mesogenic Behavior and Curing with Anhydride
Authors: Zhou De Wen , Liang Li Yan , Lu Man Geng
Published: August 2010

A series of dimeric liquid crystalline (LC) epoxy monomers containing azo groups with different length of central spacers were synthesized. The mesogenic behavior of these monomers was characterized by differential scanning calorimetry(DSC), polarized optical microscopy (POM) and wide-angle X-Ray diffraction(WAXS). Like other dimeric LC epoxy monomers, the melting points, clear points and mesophase of these compounds were influenced by the carbon numbers of the central spacers. Cure kinetics of these monomers with anhydride was studied by non-isothermal DSC at different heating rates. With the increasing of conversion, the values of activation energy show a tendency to decrease. The formation and development of LC phase during curing were also studied by POM. Finally LC thermosets with nematic phase were obtained.
Generation Process of Cutting-Edge Distribution on Grinding Wheel with Single-Point Diamond Dressing
Authors: Sakamoto Haruhisa , Shimizu Shinji
Published: August 2010

The grinding should be improved to be the skill-free process executed based on the quantified criteria. In this study, the evaluation methods are applied to evaluate the dressing process to clarify how the dressing changes the cutting-edge distribution. From the results, the following facts have been clarified: There is the critical value of the depth of cut for suppressing the release of grain. The spark-out in dressing releases grains damaged by collision with dresser, and then, it also increases the cutting-edge density.
Study on Plane Magnetic Abrasive Finishing Process - Experimental and Theoretical Analysis on Polishing Trajectory -
Authors: Zou Yan Hua , Jiao An Yuan , Aizawa Toshio
Published: August 2010

This research studies an effective polishing process to elevate the surface precision and homogeneity by improving the polishing trajectory of magnetic brush. The moment of magnetic brush is a key influence factor on finishing characteristics, but in conventional plane magnetic abrasive Polishing process, the movements of magnetic brush is relatively simple. In this paper a polishing process using the complex polishing trajectory of magnetic brush has been modified and studied by use of newly designed experiment device. The linear movement of workpiece, the rotation and revolution or movement in XY coordinate plane of magnetic brush can be realized by this device. In comparison with conventional method, variation regularity about surface roughness and the material removal are been studied. According to experimental results for polishing trajectory of magnetic brush, finishing characteristics was clarified. The results show that studies on polishing trajectory of magnetic brush are more valuable and the experimental researches are consistent with theoretical analysis. In addition, the accuracy of plane magnetic abrasive finishing can be elevated in terms of the reasonable planning for polishing trajectory of magnetic brush.
Tool Wear Mechanism in Continuous Cutting of Difficult-to-Cut Material under Dry Machining
Authors: Ibrahim Gusri Akhyar , Che Haron Che Hassan , Ghani Jaharah A.
Published: August 2010

Wear mechanism on the flank of a cutting tool is caused by friction between newly machined surface and the cutting tool, which plays predominant role in determining tool life. Detailed study on wear mechanism at the cutting edge of carbide tools were carried out at cutting speed of 55 – 95 m/min, feed rate of 0.15 – 0.35 mm/rev and depth of cut of 0.10 – 0.20 mm. The wear on the cutting tools was occurred predominantly on the nose radius, as effect of lower feedrate and nose radius selected. Various wear observed on both coated and uncoated cutting tool such as abrasive wear, adhesive wear, adhering chip on the cutting edge, flaking, chipping, coating delamination of coated tool, crack and fracture. The abrasive wear predominantly occurred on the flank face while the flaking on the rake face. Abrasive wear occurred at nose radius due to the depth of cut selected was low therefore, the contact area between the cutting tool and the workpiece material was small. Adhesion or welded titanium alloy onto the flank and rake faces demonstrated a strong bond at the workpiece-tool interface. The adhesion wear takes place after the coating has worn out or coating delamination has been occurred. The crack occurred possibly due to machining at high cutting speed and high depth of cut. Cutting at high cutting speed caused more heat generated at the cutting edge and at high depth of cut caused more cutting forces on the insert.
Progress in the Modeling of Abrasive Jet Machining
Authors: Ali Yasser M. , Mathew Philip , Wang Jun
Published: August 2010

Most existing models for abrasive jet machining (AJM) are based on erosion models for either ductile or brittle materials. This classification imposes some limitations, because most materials are neither absolutely ductile nor absolutely brittle, but lay within the continuous spectrum between those two idealizations. This work reports recent progress in the modeling of erosion processes for real materials, and discusses the implications of a new model in estimating the performance of AJM. The new model is more capable in explaining the effects of jet velocity, abrasive particle size, and various material properties on the efficiency of the cutting process.
Repairing Damage on Ground Fused Silica by CO2 Laser Irradiation
Authors: Yao Peng , Abe Takuro , Yoshihara Nobuhito , Zhou Tian Feng , Yan Ji Wang , Kuriyagawa Tsunemoto
Published: August 2010

Fused silica is an important material for optics of ultraviolet laser transmission. It is difficult to be ground in ductile mode because of a high brittleness. In this paper, ductile mode grinding was achieved by a taper grinding method when the initial surface was a polished surface. However, when the initial surface was an unpolished surface, ductile mode grinding could not be realized because of the existence of surface and subsurface damages. The damages on the ground fused silica surface were repaired by CO2 laser irradiation with optimal laser power and scanning velocity. The optimal parameters were determined by studying the viscosity of fused silica and etching depth of laser irradiated groove. Besides laser processing parameters, surface roughness of laser irradiated surface is also greatly influenced by the initial surface roughness.
Evaluation of Polished Surface for Viscoelastic Polymer
Authors: Kubo Takao , Ota Shiro , Oda Masatoshi , Hashishita Kenichi , Kakinuma Yasuhiro
Published: August 2010

Viscoelastic polymers are used as one of coating materials for protecting the products from scratches. Presently, the repair of the coating surface for removing dust or extraneous matters has been performed through several polishing processes. However, it becomes increasingly difficult to polish its surface by only applying good skill and experience of skilled worker because a leading-edge viscoelastic polymer for coating is further scratch-resistant. Thus, based on quantitative evaluation of relation between polishing process and finished surface, it is necessary to make the polishing process appropriate for the leading-edge viscoelastic polymers. In this study, we attempt to establish the evaluation method of the polished surface and clarify the surface condition with invisible scratches.
Abrasive Wear Caused by EMC Particles
Authors: Liaw Yow Ching , Chou Jung Hua
Published: August 2010

An experimental facility is built up to investigate the abrasive wear behavior of EMC particles. The parameters explored include particle impacting velocity and impacting angle. The results show that the erosion rate depends on both the particle impacting velocity and impacting angle. A higher velocity will cause more erosion whereas a smaller impacting angle will cause more erosion, especially at higher impacting velocities. Furthermore, the morphology of the eroded particles is irregular in shape and a smaller impacting angle will result in a larger dimension of the eroded particles.
Effect of Ground Surface Roughness of Tool on Adhesion Characteristics of PVD Coating
Authors: Furuno Masahiro , Kitajima Koichi , Tsukuda Yousuke , Akamatsu Takeshi
Published: August 2010

This study investigated adhesion of coatings on a grinding surface. This was carried out using scratch testing as a function of surface roughness. Three types of coatings were explored: TiAlN, CrSiN and TiSiN. With smaller surface roughness, the coating adhesion showed a tendency to become stronger. In particular, in the case of surface roughness under 2 micrometers for a coating, the coating adhesion was good. Specifically, the CrSiN coating yielded a very smooth surface.
Process Influences in the Wire Cutting of Concrete
Authors: Denkena Berend , de Leon Luis , Seiffert Florian
Published: August 2010

The wire sawing process is a highly flexible cut-off grinding process. Nowadays it is not only used in its traditional field of application (processing of natural stone) but also in the civil construction industry and for the destruction of metallic structures. In order to extend the knowledge about the process it is one goal of the Institute of Production Engineering and Machine Tools (IFW) of the Leibniz Universität Hannover, Germany, to investigate the cutting mechanisms. These are supposed to be the basis for a tool design taking into account the specific field of application. The results presented within this paper describe an approach to explain the interdependencies of the system and manipulable variables for the wire sawing process. From these interrelationships the cutting mechanisms will be derived.
A Novel Piezoelectric Grinding Dynamometer for Monitoring Ultra-Precision Grinding of Silicon Wafers
Authors: Zhang Jun , Liu Bo , Qian Min , Zhu Xiang Long , Kang Ren Ke
Published: August 2010

A Novel Piezoelectric Grinding Dynamometer for Monitoring Ultra-precision Grinding of Silicon Wafers
Online Cutting Tool Wear Monitoring Using I-Kaz Method and New Regression Model
Authors: Ghani Jaharah A. , Rizal Muhammad , Nuawi Mohd Zaki , Che Haron Che Hassan , Ghazali Mariyam Jameelah , Rahman Mohd Nizam Ab.
Published: August 2010

This study presents a new method for detecting the cutting tool wear based on the measured cutting force signals using the regression model and I-kaz method. The detection of tool wear was done automatically using the in-house developed regression model and 3D graphic presentation of I-kaz 3D coefficient during machining process. The machining tests were carried out on a CNC turning machine Colchester Master Tornado T4 in dry cutting condition, and Kistler 9255B dynamometer was used to measure the cutting force signals, which then stored and displayed in the DasyLab software. The progression of the cutting tool flank wear land (VB) was indicated by the amount of the cutting force generated. Later, the I-kaz was used to analyze all the cutting force signals from beginning of the cut until the rejection stage of the cutting tool. Results of the I-Kaz analysis were represented by various characteristic of I-kaz 3D coefficient and 3D graphic presentation. The I-kaz 3D coefficient number decreases as the tool wear increases. This method can be used for real time tool wear monitoring.
On-Line Inspection of the Surface Roughness of Workpiece in Ultraprecision Machining
Authors: Tsai Hsi Hsun , Feng Hui Ping
Published: August 2010

An in situ technique to determine the surface roughness of ultraprecision machining using optical characteristic effects is fundamental as probes are not used, which prevents contact damage on the surface. Because the plastic lens molding reprints the roughness of the mold core fabricated by machining, tool marks result in the poor surface of the plastic lens. The machined surface can reflect the input light of a green laser with a short wavelength of 532 nm. By varying the feed rate of the ultraprecision machining, several samples of the electrolyte-less nickel with different surface roughness have been examined using the green laser and the photodiode array. The distribution of the optical scattering effect of each sample under the light source of green laser is derived for prediction of the surface roughness. The results show that greater surface roughness produces more expansive distribution of light scattering. In addition, the bidirectional scatter distribution function (BSDF) of the machined surface is found to be proportional to roughness. Using the ratio of the main and the side measuring channels of the photodiode array, a suitable approach to establish the relationship between light scattering and surface roughness can be developed. The laser and the photodiode array are found to efficiently predict the surface roughness of the ultraprecision machined electroless nickel.
Development and Analysis of Special-Shaped Stone Multi-Function NC Machining Center
Authors: Zhang Ke , Zhao De Hong , Guo Hua , Hou Bao Jia , Wu Yu Hou
Published: August 2010

Along with building decoration industry and stone industry development, special-shaped stone equipments develop to high speed and efficiency, intelligent, compound function directions. Special-shaped stone multi-function compound machining center was designed, realized stone turning function and carving and milling function compound in a perpendicular saddle, analyzed machining center motion function. Kinetic simulation research on machining center was performed using COSMOSMotion, tracked spindle tool output displacement, speed and acceleration data by trajectory tracking, indicated mathematic model correct. Structure design was optimized through analysis of crossbeam and bed. This had important practical value to dynamic design of NC equipment and prototype research.
Experimental Study on Milling Hardened SKD Steel Using Micro CBN Ball-End Mills
Authors: Liu Yung Tien , Chiu Neng Hsin , Lin Yen Chun , Lai Chih Liang , Lin Yu Fu , Chiu Hung Hsiang
Published: August 2010

Micro ball-end milling process features the ability of machining complex surfaces, precision machining accuracy, and excellent machined surface roughness. However, because the diameter of a micro milling tool is very small, a rapid progress of tool wear or even tool breakage usually happens when machining a high-strength hardened mold steel using improper machining parameters. As a result, the machining cost would rise due to the quality defect in machined workpiece. In this study, to investigate how the machining parameters affect the cutting behaviors, a series of experiments using micro CBN ball-end mills with a diameter of 0.5 mm were performed to cut the SKD11 mold steel with hardness of HRC 61. The machining parameters are selected as the feeding speed (f) being 840, 960 and 1,080 mm/min, depth of cut (ap) being 30, 45, 60 μm, and spindle speed (vs) being fixed as 30,000 rpm. According to the experimental results, the measured three-axis cutting forces, flank wears, and surface roughness of machined workpiece are highly related to the cutting length. It is expected that the measured results can be used to construct a performance function of a micro ball-end tool. With referring to the performance function, the tool life can be well expected, and thus a progress in machining efficiency without tool failure can be achieved.
Drilling Force and Temperature of Bone by Surgical Drill
Authors: Yang Yi Xin , Wang Cheng Yong , Qin Zhe , Xu Lin Lin , Song Yue Xian , Chen Han Yuan
Published: August 2010

Drilling force and temperature of tibia at the high speed drilling for improving the design of surgical drills are very important. In this paper we describe experiments using pig tibia bones, measuring the drilling force and temperature of a new design of drill bit and compare the results against a twist drill. The result shows that the drilling force and temperature are affected by the feed rate and drilling speed, which vary with the drilling depth into the bone. The new surgical drill with three top cutting edges can achieve lower temperature below 47oC and lower drilling force than with the stainless steel twist drill and carbide twist drill.
Modeling Aspect Ratio of a Micro EDM Hole
Authors: Yin G. , Yu Z. , An C. , Li J.
Published: August 2010

Micro electrical discharge machining (EDM) has the ability to drill micro holes with high accuracy in metallic materials. The aspect ratio of a micro hole generated by micro EDM is usually higher than those by other processes such as etching, mechanical drilling, and laser. However, it was found that the drilling speed of micro EDM slows down and even stops when the aspect ratio reaches a certain value. To understand this phenomenon, a theoretical model is proposed based on the fluid mechanics and surface tension. Experiments under different machining conditions are carried to verify this model. Experimental results agree with the theoretical values, which indicate the validity of the proposed model. The difference between the theoretical values and the real values might be caused by the debris and the temperature in the discharge gap, which are ignored in the model.
Influence of the Electrochemical Dissolution Effect on the Material Removal Rate Utilizing Electrokinetic Phenomenon
Authors: Leo C.S. , Butler David Lee , Ng Sum Huan , Danyluk Steven
Published: August 2010

Recently, material removal utilising electrokinetic phenomenon was proposed as an alternative to create material removal at the nanometric level [1]. The concept of the introduced material removal process is to impinge particles contained in the slurry, under the influence of hydrodynamic and electrokinetic effects, onto the workpiece with a predetermined velocity to create material removal on the surface. The material removal process proved to be feasible where the material removal rate was reported to be in the range of a few hundred nm/hr with a surface roughness of a few nm (RMS). This paper aims to look into the effect of the electrochemical dissolution on the material removal process since high voltages are involved during the material removal process. During the experimental study, electrochemical dissolution was observed and it contributed a certain proportion of the material removal process. However, the main material removal mechanism still relies on the mechanical action of the abrasive particles on the surface of the workpiece to create material removal during the process.
In Situ: A Novel Approach for the Production of Micro Holes
Authors: Somashekhar K.P. , Ramachandran N. , Mathew Jose
Published: August 2010

This work is on the preparation of microelectrodes for μ-EDM operation using μ-WEDG process. Electrodes of Ø500 μm are fabricated with various discharge energy machining conditions. Effects of gap voltage, capacitance & feed rate on the surface finish of the electrodes and overcut of the thus produced micro holes are investigated. The profile of microelectrodes is measured using surface roughness tester with 2μm stylus interfaced with SURFPAK software. The study demonstrated that for brass electrodes an arithmetic average roughness value as low as 1.7μm and an overcut of 3 µm could be achieved. The significant machining parameters are found using ANOVA. Surface of the produced microelectrodes are examined using Scanning Electron Microscope. μ-WEDG process parameters could be adjusted to achieve good surface integrity on microelectrodes. Experimental results showed that the surface roughness of microelectrodes depended primarily on feed rate of the electrode. The observations showed the clear and quantitative correlation existing between the micrometer level surface quality and process parameters. The resulting microelectrodes are found to be of exceptionally high quality and could be used for μ- EDM operation on different types of work materials.
Optimal Cutting Parameters for Desired Surface Roughness in End Milling Inconel 718
Authors: Wang Yuan Wei , Zhang Song , Li Jian Feng , Ding Tong Chao
Published: August 2010

In this paper, Taguchi method was applied to design the cutting experiments when end milling Inconel 718 with the TiAlN-TiN coated carbide inserts. The signal-to-noise (S/N) ratio are employed to study the effects of cutting parameters (cutting speed, feed per tooth, radial depth of cut, and axial depth of cut) on surface roughness, and the optimal combination of the cutting parameters for the desired surface roughness is obtained. An exponential regression model for the surface roughness is formulated based on the experimental results. Finally, the verification tests show that surface roughness generated by the optimal cutting parameters is really the minimum value, and there is a good agreement between the predictive results and experimental measurements.
The Research of Modulation Period on Photoelectric Properties of Ti/TiN Multilayer Films
Authors: Hu Min , Liu Ying
Published: August 2010

A series of Ti/TiN multilayer films were prepared by reactive DC magnetron sputtering onto Si(111) substrates. The resistivity and optical reflectance of these thin films were measured as a function of the modulated, multilayered thickness and the number of layered structures. The resistivity decreased with increase in the number of layers in the film up to 4 layers. The reflectance in the near infrared region increased with increase in layer thickness but after a certain thickness, the change in reflectance was minimal. An optimum thickness of 25 nm for the modulated film realized a maximum of 0.829 in the near infrared reflectance. With the number of layers greater than 15, an interfacial layer of Ti2N was observed.
A Study of Mechanical Properties of Human Femoral Heads Using Nanoindentation
Authors: Lin Chih Ling , Huang Han , Cribb Bronwen W. , Russell Anthony
Published: August 2010

Human bone fracture associated with osteoporosis was hypothesized to be related to the alteration of mechanical properties in bones. In this work, cortical and trabecular bones from human femoral heads were studied. Bone samples of eight female and four male patients, with ages varying from 37 to 93 years, were collected from total hip replacement surgery. Reduced modulus (Er) and hardness (H) of osteons, interstitial lamellae and trabeculae were characterized by nanoindentation. The results showed both the reduced modulus and hardness of the interstitial lamellae were significant higher than those of osteons and trabeculae. Though there was no significant difference in microstructures in the Group A (age < 60 years) and B (age > 60 years), the Group B bones demonstrated to be stiffer.
Synthesis and Application of a Modifier with Low Formaldehyde Emission to Enhance General Wood Properties
Authors: Jiang Yi Fei , Wu Guo Feng , Song Shu Ping , Chen He Yu , Pu Jun Wen
Published: August 2010

A preparation method of Urea-formaldehyde performed polymer(UFP) with low molecular weight and high reactivity is presented. The UFP can impregnate into wood along trachea from the ends with pressurized impregnation method. In the following heating and pressing processes of the wood, the UFP polymerizes, and it enhances stability and strength of the wood. The impregnating-pressing-drying method avoiding the disadvantage of dealing with the large specimens using vaccum-pressing method is suitable for industrial production. Results from test showed the degree of crystallinity tested by XRD were 30%, 32% in different dosage of the modifier. Utilizing a combination of low molecular weight resin impregnation and pressing resulted in a density increase of UFP treated wood from 0.214 to 0.268g/cm3. At the same time, the Young’s modulus and bending strength increased from 1.407GPa to 1.759GPa and 64MPa to 74.5MPa, respectively. But the formaldehyde emission is great reduced from 0.5% to 0.008%. It can be concluded that the effective utilization of UFP impregnated in wood is a promising technique for the production of high-strength in the drying and pressing processing.
Microscopic Analysis and Experimental Research on Thermal Mechanical Behavior of Natural Aggregate Concrete
Authors: Yan H.Q. , Wang Qingyuan
Published: August 2010

Reinforced concrete construction is very common recently and extensively used both in industrial and commercial buildings. With the gradual rise in occurrences of fire accidents in recent years, a more thorough and quantitative understanding of the damage phenomenon in concrete structures is required. However, the mechanical behavior of concrete could actually be more complex under high temperature conditions than at room temperature. Restoration and reinforcement of the structures exposed to fire may have to be based on residual strength analysis and therefore require a correlation between temperature and mechanical properties. Thus, in order to meet the modern challenges of rapid engineering advances and societal development, further research on the concrete material and its structural behavior at high temperatures becomes extremely important.
The present paper deals with investigations on the effect of high temperature exposure on the compressive strength of natural aggregate concrete. Experiments were conducted to study the compressive strength variations with increasing temperatures, up to 700 °C, and the subsequent cooling modes such as natural and spray cooling. Results show that the compressive strength gradually decreases with increasing temperatures. And micro-structural observations of the concrete specimens by means of scanning electron microscopy (SEM) were obtained. These test methods and results can be used for analyzing and investigating the behavior of recycled aggregate concrete with increasing temperatures.
The Application of Dynamic Finite Element Method in Beam Structure
Authors: Yang Li Cheng , Qing Shang Le , Huang Xuan , Luo Yi Ping
Published: August 2010

When the practical problem is solved based on finite element method, researchers are often transformed dynamic problem into static one in order to simplify calculation, which brings to large error generally. FEM is good method in solving dynamic characteristics of structure by using only drawings, project and related experienced knowledge. By analyzing the similarities and differences between static FEM and dynamic FEM and discussing their basic principles, the calculation results of static and dynamic FEM are discussed according to the example of simply supported beam with simple harmonic excited force in its midpoint position. The results show that dynamic finite element method has higher solution precise than static one in dealing with practical dynamic problem.
Reversing Clogging in Vertical-Flow Constructed Wetlands by Backwashing Treatment
Authors: Ma Fei , Jiang Li , Zeng Ting
Published: August 2010

More and more constructed wetland CW) were used to treat waste water in the world for its advantage on cheaper and efficiency. CW would clog for improper design or imperfect management, so application for it was limited. The purpose of this paper is that using backwashing method resolve filter media clogging problem which is an intractable matter in constructed wetlands project. The effects of the backwashing treatment on pollutant removal, as well as the influence on characteristics of hydraulics of wetlands, were studied. The experimental results indicate that CW hydraulic conductivity, hydraulic resistance time and removal rate of COD increased after backwashing. This paper confirmed that backwashing method can reverse clogging in vertical-flow constructed wetlands, and provided design guidance for applying backwashing method to treat clogging vertical-flow constructed wetlands.
The Rack-Pinion Gearing for High Order of Contact
Authors: Liu Hu Ran
Published: August 2010

After an extensive research on the fundamental theory, the theoretical basis for the gearing with equal conjugate curvature is presented in this paper. This includes the theory for gear meshing with high oder of contact. In comparison to previous studies, the theory of this paper is more restricted going beyond third order parameters into the fourth order, the teeth profile had one order of contact higher than that of the ordinary gearing. So that further improved the contact strength of tooth profile. A large category of gearings with high order of contact was presented. The rack-pinion gearing with equal conjugate curvature is one of them. In my gearing the curvature center of media rank extend along the pitch line continuously and steadily.
Dynamic Analysis for Rotary Detecting Table of ICTY
Authors: Liu Li , Liu Tie Jun
Published: August 2010

In order to know whether the ICT rotary detecting table can achieve its work requests, performance and structure characteristics of ICT scanning worktable are analyzed. In view of the rotary detecting table turning motion, the method of finite element is used to do dynamic analysis. According to the structure and working features of the rotary detecting table, it is modeled. Then, in terms of the actual operating mode, the model is done the analysis of modal and transient dynamic. The deformation curve figures and dynamic response curve figures are received. By deformation analysis and stress analysis, the dynamic performance of this structure meets design requirements.
Influence Research of Velocity on Lubricating Properties of Sector Cavity Multi-Pad Hydrostatic Thrust Bearing
Authors: Yu Xiao Dong , Xiang Hong Jun , Lou Xiao Zhong , Meng Xiu Li , Jiang Hui , Ji Wei Dong , Yang Chang Qing , Sun Xian Zhu
Published: August 2010

Lubricating characteristics of sector cavity multi-pad hydrostatic thrust bearing are affected significantly by velocity, poor design can cause lubricant film rupture and dry friction, even leading to failure of hydrostatic bearing tribology. For this problem, the Computational Fluid Dynamics and the lubrication theory have been used to analyze velocity characteristics of the parameters such as cavity pressure of oil, oil cavity flow and film thickness, to gain relationship between velocity and lubricating properties of sector cavity multi-pad hydrostatic thrust bearing, avoiding the occurrence of hydrostatic bearing tribological failure. It is shown that along with the speed of the worktable increasing, the flow of lubricant oil caused by inertia and centrifugal force become larger, the flow of efflux from the oil cavity also become larger, causing the pressure drop of the oil cavity, the thinning of the film thickness, the occurrence of film rupture and dry friction and failure of hydrostatic bearing tribology. The study provides the basic data for the hydrostatic thrust bearing design, the lubrication and the experiment, implements of the prediction of the hydrostatic thrust bearing lubrication velocity characteristics, and reaches the purpose of reducing economic loss.
The Helical Gear with Equal Conjugate Curvature
Authors: Liu Hu Ran
Published: August 2010

Inspired from the serious plastic deformation of some gears with heavy power transmission in practical usage in metallurgical industry, we believe that there must existed some kind of gear profile which is most suitable in both the contact and bending fatigue strength. The aim of this paper is intention to produce a gearing of these properties. From careful analysis and deep going investigation, we think that it is the profile of equal conjugate curvature with high order of contact, and analyzed the forming principle of this kind profile in mathematic method. The contact stress is so low that even the Hertz theory, with which the contact stress can be calculated for most of gearing, is invalid. This paper researched how to realize this kind of gearing.
Self-Crosslinking and Cocrosslinking with Styrene of the Unsaturated Poly(silyl ester) and Characteristics of the Crosslinked Product
Authors: Han Nian Feng , Zhou De Jie , Tang Xin De
Published: August 2010

The unsaturated poly(silyl ester) has been prepared by the polycondensation reaction of 1, 3-dichloro-tetramethyldisiloxane with di-tert-butyl fumarate. To investigate the crosslinking reaction of the unsaturated poly(silyl ester), poly(tetramethyl disilyloxyl fumarate) was self-crosslinked and cocrosslinked with styrene in the presence of 2, 2'-azobis(isobutyronitri1e) (AIBN) as a radical initiator. After the crosslinking, the unsaturated poly(silyl ester)s, which were viscous liquids, turned into solid products. The characterization of the poly(silyl ester) and the crosslinked product included infrared (IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Comparisons were made between the linear poly(silyl ester) and the crosslinked products. It was found that after crosslinking, the important resonance signal for ethenylene (C=C) of the poly(silyl ester) disappeared, which show that the crosslinking reaction is carried out progressively. The glass-transition temperatures of the self-crosslinked and cocrosslinked product were higher than that of the uncrosslinked poly(silyl ester), and the thermal stability of the crosslinked poly(silyl ester)s was better than that of uncrosslinked poly(silyl ester). In degradation tests, the self-crosslinked product degradable completely in 35 minutes and the cocrosslinked product complete mass loss in 5 days and the release of PNA followed the degradation of the crsslinked product. The rate of degradation of the poly(silyl ester) decreased after the crosslinking.
Study on Heating Steady Temperature Field in a ZrO2/FGM/Ti-6Al-4V Composite Plate Considered Temperature Dependency Based on NFEM
Authors: Xu Yang Jian , Tu Dai Hui
Published: August 2010

The steady temperature distributions in a ceramic / metal composite FGM plate with temperature-dependent material properties during heating process were investigated by the NFEM. From numerical calculation, when T0=300K, Ta=650K and Tb=1 700K, the temperature distributions in the composite FGM plate were obtained. The results are as follows. With the increase of the FGM gradient layer thickness and when M=1, the temperature distributions in the composite plate are more reasonable. With the increase of porosity, the variations of the temperature curve become big obviously, and there is an abrupt change for the temperature at =0.5, its value is about 917K, but the temperature curve is gentle and smooth at the bonding interfaces of the three-layered composite FGM plate. Compared with the nongraded two-layered ceramic/metal composite plate, the temperature of the ZrO2/FGM/Ti-6Al-4V composite plate is very gentle. When the temperature dependency of the material properties was considered, the temperature in graded three-layered composite FGM plate becomes small obviously. The results provide the foundations of theoretical calculation and the further analysis of thermal stress for the design and application of the composite plate.
Study on Parameter Optimization for Polishing
Authors: Zhang Mian Hao
Published: August 2010

Polishing is a manufacturing process for surface-smoothing. To minimize surface damage and defects, gentle polishing conditions are required. The main objective of this research is to determine the effect of polishing conditions by using Taguchi method , and to optimize the process parameters to obtain the best surface possible. The experimental results indicate that a set of optimal polishing conditions for producing work surface within the range of parameters evaluated, double oblique polishing path, relatively high speed and low feed rate are desirable for improve surface.
Experimental Research on the Robotic Compound Polishing Process with Mixed Magnetic Abrasive
Authors: Han Guang Chao , Sun Ming , Li Jing Dong
Published: August 2010

The quality and the efficiency of the polishing process are important to the lead time of the rapid tooling. Robotic polishing process with free abrasive is adapted to the finishing of complex mould surface, in which the soft polishing tool is widely used. But the stability and the efficiency of the process should be improved further. According to the moving and grinding characters of the free abrasive, the mixed magnetic abrasive and the minitype electromagnetic field are combined to the robotic polishing process. The mixed magnetic abrasive are made up of magnetic grain and hard abrasive, which can enhance the effective cutting and grinding process of the three-body abrasion under the effect of magnetic field. The robotic compound polishing process with mixed magnetic abrasive is presented in this paper. The experiments are tested to study the distribution of the minitye magnetic field and the polishing efficiency of the complex polishing process. The results show that the polishing efficiency of the process can be improved obviously where the effective working intensity of the electromagnetic field reaches 400Gs.
The Application of “Three-Box” Energy Analysis Method on the Combined-Station
Authors: Jia Yong Ying , Wang Ying , Liu Xiao Yan , Wang Zhi Guo
Published: August 2010

Aim at energy consumption for oil production increased year by year and the generally low energy utilization. this paper is based on the model of three-box energy analysis, take the oil gathering and transferring system of the 4th combined-station of Shuguang Oil Production as the object of study, established the "three-box" combinative energy model, analysed and evaluated of its energy usage and found out the weak links of energy usage in the system. The evaluation results indicate that the energy utilization of the 4th combined-station of Shuguang Oil Production system is low, the major parts of energy loss are in a furnace, tanks, pipe network and pumps. The study provides a reliable scientific basis for the energy saving reform of gathering and transferring system of oilfields.
Finite Element Modeling of the Geometry Size Effect for Adhesive Joints Strength
Authors: Lu Chao , Xia Mei Ling
Published: August 2010

Based on 3D elastic-plastic finite element method (FEM), the geometry size effect on strength in aluminum alloy adhesive joints is presented in this paper. The numerical and experimental results show that with the adhesive thickness increased, the adhesive joint strength first increases then decreases, and in a certain range, with the adhesive thickness increased, the adhesive joint strength is nonlinear to the overlap length but linear to the overlap area. In the case of the same overlap area, the adhesive joint strength can be increased by increasing overlap length and decreasing overlap width.
On the Effect of Curvature Radius on the Spif-Ability
Authors: Hussain Ghulam , Lin Gao , Hayat Nasir , Iqbal Asif
Published: August 2010

Single Point Incremental Forming (SPIF) is a novel sheet metal forming process. The formability (i.e. spif-ability) in this process is determined through Varying Wall Angle Conical Frustum (VWACF) test. In this paper, the effect of variation in the curvature radius, a geometrical parameter of test, on the test results is investigated. A series of VWACF tests with a variety of curvature radii is performed to quantify the said effect. It is found that the spif-ability increases with increasing of curvature radius. However, any variation in the curvature radius does not affect the spif-ability when the normalized curvature radius (i.e. curvature radius/tool radius) becomes higher than 9.
Study on the Characterization of Zinc Ferrite High-Temperature Coal Gas Desulfurization Agent
Authors: Xu Hong Yan , Liang Mei Sheng , Li Chun Hu
Published: August 2010

Using ferric nitrate, zinc nitrate, ammonia liquor and binder as main raw materials, five kinds of zinc ferrite sorbents were prepared by the co-precipitation method. The effects of the different binders on the structure and texture of zinc ferrite sorbents were investigated. The morphology, composite structure, pore properties, and mechanical strength were studied by using modern several physicochemical techniques such as powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), strength tester and gas absorption meter. It is showed that spinel structure ZnFe2O4 is not affected by different binders，and its particle diameter is in micron leve1. The spinel structures are present in the sorbents that have been calcined at 750 0C.. The sorbent employed kaolinite as binder is the best one of the five types of sorbents for desulfurization, while the one employed diatomite is the worst.Different binders modify the textural properties, modifying consequently the sorbent reactivity. Furthermore, the reactivity and sulfur capacity of sorbents are increasing with an increase in the pore volume.
Viscosity Models Based on Network Theory for Polymer Melts
Authors: Xu Hai Hang , Zhong Lei
Published: August 2010

New shear and extensional viscosity models based on Fredrickson kinetic equation coupled with Dewitt constitutive equation were established to predict viscosities of polymer melts. The experimental data of 125°C LDPE and LDPE filled with 35% glass beads reported from references were compared with the model predictions. The predictions showed good agreement with the measurements. The models are simple and easy to use. Because they contain no structure parameter, they are capable to describe the viscosities of pure polymer and polymer composites.
Finite Element Analysis and Design Improvement for Ends Warping of Refrigerator Door
Authors: Wang Zhi Wei , Meng Ling Qin , Li Yan Qin , Li Yong Gao , Zhang De Hai
Published: August 2010

Facing the ends warping of refrigerators door, a refrigerator door is simulated using finite element theory and ANSYS software. The enclosed of finite element model and geometric model are established to conduct computing. The results show that simulated values of end warping are significantly greater than the given value of company technique standard. Several structural design schemes are proposed on the basis of production practice and theory analysis. The only one scheme of design improvement is chosen to compute using ANSYS, the results show the values of warping ends are significantly reduced and can meet the production requirements. The reasonable of finite element analysis is proven effectively through long time production.
NiO Development on FeCrAl Substrate for Catalytic Converter Using Ultrasonic and Nickel Electroplating Methods
Authors: Sebayang Darwin , Yanuandri Putrasari , Hasan Sulaiman B. , Untoro Pudji
Published: August 2010

The irregular surface roughness morphology due to ultrasonic method was used approach for increasing the high surface area of substrate and catalyst. The purpose of this paper is to show the ultrasonic and nickel electroplating methods for NiO automotive catalyst development on FeCrAl substrate. The process began with pretreatment of FeCrAl using SiC and/or Al2O3 solution agitating by ultrasonic and followed with nickel electroplating. The oxidation test was conducted for developing the NiO. The physical morphology structure of the presence NiO on the FeCrAl substrate was analyzed using scanning electron microscope (SEM) in combination with energy dispersive X-ray spectroscopy (EDS). The cross sectional observation show the NiO catalyst completely existed on the FeCrAl. The ultrasonic method increases the irregular surface roughness morphology on FeCrAl substrate that influenced the homogeneous and stability of nickel electroplating and NiO surface area development.
Study of Access Algorithms in Wireless Network
Authors: Zou Chi Jia
Published: August 2010

The measure to improve the performance of the wireless network channel is of great significance to the building in the wireless network. Due to IPv6 Agreement is the agreement for the next generation network and the core of it, IPHC header compression technology provides IPv6 basic headers and expanding headers with a good support, so we adopt IPHC header compression scheme which groups the data that need to transmitting, introduce retransmission mechanism and header request mechanism to make IPHC have much compression effect on headers. But IPHC header compression scheme is hard on signal channel, it required that loss rate of transportation link is a little lower. In order to let IPHC better adapt to wireless link, compression based on link state is offered: Using simple portioned Markov model to check channel error rate, adopting RTS/CTS access mechanism to search for link state. Apply OPNET simulation software to imitate and finally achieve the desired target.
In past two decades, computer network got rapid development, with the application of computers wider and wider. But because of being limited by areas and time, users couldn’t surf on the Internet, communicate with each other, and transport messages at any time and at any place. In this case, the wireless network developed, wireless network technology also produced therewith. Computer wireless network technology included IEEE802.11 collection [1], bluetooth technology, infrared technology, and broadband wireless technology afterwards and so on. Wireless communication technology contained CDMA, GSM, etc [2-5]. According to access ways, wireless access technology was divided into fixed wireless access technology and mobile wireless access technology with many small parts. Wireless access system consisted of wireless base station, wireless base station controller, operation maintenance center and user units. User units which contained single units and multiunits were connected directly with user terminals. Base station, which provided signal-sending and signal-receiving services for users in one district, was controlled by the controller called center station facility to provide an interface with base station side and operation maintenance center, wireless signal channel control and base station monitor, complete the connection of exchanges and routers. Operation control centre is responsible for operating and maintaining wireless access system machines and managing daily network operations.