bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of La1-xSrxMnO3 Materials by High Temperature Solid Phase Method
Authors: Li Zeng Gang , Chu Zeng Yong , Zhou Yong Jiang , Cheng Hai Feng
Published: September 2012

La1-xSrxMnO3 (LSMO) (x=0.1, 0.2, 0.3, 0.4)powders were synthesized by high temperature solid phase method, and the crystal structure and morphology were characterized by XRD and SEM. Results indicated that the pure perovskite type LSMO could be obtained after sintered at the temperature of 1000°C for 6h. The average particle size of the powders decreases with the increasing concentration of Strontium.
Study of New Atomization Mechanism for Manufacturing Metal Powder
Authors: Qiu Ke , Luo Feng , Zhao Dong Fang , Li Zhong Lei , Sun Jin Peng
Published: September 2012

The paper introduces a new atomization mechanism combining the centrifugal, the oscillating and the impact breakage atomization as a trinity, breaking through the traditional single atomization model. The atomization mechanism here makes full use of the comprehensive effects of the centrifugal atomization, the oscillating atomization and the impact breakage atomization, synthesizing the superiorities of the three as an organic and powerfully efficient whole, and making their mutual reactions stronger step by step. The impact breakage atomization is a new auxiliary mechanism among the three, which can improve the atomizing process of droplets considerably after the centrifugal and the oscillating atomization, producing much better an atomizing result. It is very convenient, simple and direct to fulfill the three-in-one. This atomization mechanism can achieve the goal of even atomization and much tinier droplets and be energy-efficient with low cost as well. Therefore it is a highly practical and useful method.
Syntheses and Evaluation of Copolymer 6-Aminohexanoic Acid and 4R-Hydroxy-L-Proline for Bone Repair
Authors: Jiang Jia Chun , Zhao Zhi Tong , Lv Guo Yu , Yan Yong Gang , Wu Deng Xue
Published: September 2012

A novel synthetic copolymer (PAA) for bone repair was prepared by melt condensation polymerization with 6-aminohexanoic acid (He) and 4R-hydroxy-L-proline (Hyp). The structure and thermal property were characterized by infrared spectrometer (IR), nuclear magnetic resonance (H1NMR) and differential scanning calorimeter (DSC). The results indicated that the PAA had amide linkages in their polymer chains. The Tg of PAA was 57.56°C and significantly higher than that of nylon6, 50.46°C. Meanwhile, the intrinsic viscosity and mechanical properties were investigated at different He/Hyp ratios. It revealed that appropriate introduction of Hyp group could control the degree of polycondensation and adjusted mechanical properties of PAA obviously close to natural bone. The prepared polymers had about 2.12~18.21 % weight loss after 8-week soaking in PBS, showed degradable properties which was essentials to new bone growth. The copolymer of He and Hyp with ratios of 90/10 had 6.57 % weight loss and maintained the yield compressive strengths with about 67.51 MPa after 8 weeks, which exhibited a compatible mechanical properties and degradation speed for bone repair.
Investigating Time Dependent Mechanical Properties of Epoxy with Nano Particles by Using Indentation Tests
Authors: Ruan Guo Wei , Chuang Ming Chen , Yen Hsing Han , Lu Chin Tu , Liou Nai Shang
Published: September 2012

The objective of this study was to examine the time dependent mechanical properties of epoxy without/with nano particles composites and how the nano particles in the epoxy affect the relaxation properties of epoxy. Furthermore, viscoelastic constitutive models of epoxy and epoxy composite were established and the corresponding mechanical parameters were obtained by using inverse iterative finite element procedure. The ramp-hold indentation tests were used to investigate the time dependent mechanical properties of epoxy with and without Al2O3 nano particles. Experimental results showed that adding Al2O3 nano particles in to epoxy can reduce the relaxation effect of epoxy.
Study on the Weldability and Metallurgical Structure of 15CrMoR
Authors: Hu Xiao Dong , Lv Jian Tao , Zhang Yong , Zhang Sen , Li Ya Jiang
Published: September 2012

The butt weld of 15CrMoR with the thickness of 55mm has been manufactured with the bonding methods of manual electric arc welding (SMAW) and submerged-arc welding (SAW), and the mechanical properties of which have been tested with the corresponding test, and the metallurgical structures have been analyzed with microscope. Conclusions have been obtained as following: the metallurgical structure of multi-layer butt weld is much more complicated than the monolayer ones; only the last weld layer has the obvious zones of weld zone, heat-affected zone (HAZ) and fusion area; the weld zone and the fusion area will be heat treated with the next layers weld finished; the mechanical property of the multi-layer butt weld is much better than the monolayer weld.
The Research on Variety of Instantaneous Transmission-Ratio of Gear Pump with Circular-Arc Tooth Profile
Authors: Zhang You Chen
Published: September 2012

According to basic law of tooth profile meshing and principle of higher pair to be replaced with lower pair of planar mechanism, the calculating formula which is used for calculation of transmission ratio of gear pump with circular-arc tooth profile is obtained. The calculating results indicate that stability of transmission ratio of gear pump are very effected by the difference between concave arc radius of tooth profile of pinion and convex arc radius of tooth profile of wheel gear. The smaller the difference of radiuses, the more severe the wave of velocity while meshing.
Performance of De-Energized Polymeric Insulating Material under Various Environment Stresses
Authors: Nazir Muhammad Tariq , Nazir Muhammad Shahzad , Jiang Xing Liang , Akram Shakeel
Published: September 2012

Outdoor electrical insulators form an important link in an electric power system. Along with the traditional insulators like glass and porcelain, presently the polymeric insulators are also used world widely. These polymeric insulating materials are very sensitive to various environmental parameters such temperature, raining, pollution, UV-radiations and icing etc. which seriously effect their electrical, chemical and hydrophobic properties. This paper shows a dynamic change of hydrophobicity on the surface of polymeric insulator under different environmental and contamination stresses. The hydrophobicity decrease of polymeric insulating surface due to rain and icing, hydrophobicity transfer status though different pollution layers and hydrophobicity recovery at different temperatures, humidity and wind speed are carried out in this paper. The hydrophobic characteristics are studied by measuring static contact angle on the surface on polymeric insulating material.
General Formula of Mobility Calculation for Planar Mechanism
Authors: Yang Yan Dong , Zhang Yi Tong
Published: September 2012

Deficiencies are existed for currently formulas of mobility calculation for planar mechanism. They are not suitable for planar mechanism with virtual constraints and the number of general constraints equal to 4. To solve the problem, the new concepts of virtual loop, virtual-loop constraint and virtual pair are defined to establish a general f ormula for DOF of planar mechanism; the calculation method for virtual-loop constraint and the mobility of link-group are also given. It is proved that the new formula is correct, general, simple and effective through the mobility analysis of several different kinds of planar mechanisms.
Intervallic Coiflets for Numerical Calculation of Dynamic Stress Intensity Factor
Authors: Xuan Jian Ping , Liu Yuan Feng , Shi Tie Lin
Published: September 2012

There are lots of practical problems which are related to the solution of Fredholm integral equations of the second kind. The present work proposes intervallic Coiflets for solving the equations. Illustrative problem involving dynamic stress and electric fields of a cracked piezoelectric excited by anti-plane shear wave is addressed. Permeable boundary condition has been used to obtain a pair of dual integral equations of the symmetric and antisymmetric parts which can be reduced to the solutions of two Fredholm integral equations of the second kind. The dynamic stress intensity factor is expressed in terms of the right-end values of two unknown functions in Fredholm integral equations. The two unknown functions are solved by intervallic Coiflets which have less the endpoints error. And intervallic Coiflets have low calculation cost and high accuracy due to the wavelet expansion coefficients are exactly obtained without calculating the wavelet integrations. The calculation results agree well with the existing method, which show the high accuracy of the estimation and demonstrate validity and applicability of the method.
The Optimization Design on the Truss Girder of Portal Crane
Authors: Zhou Xin Xiang , Guo Shu Jun , Tang Yan Ling , Tian Rong Liang
Published: September 2012

This paper takes grab type portal crane of a steel branch as the research object, its main girder is the truss structure. The truss girder is optimized with the ANSYS software, through which the size of the structure when the force of the whole truss is minimum can be found. A best plan is determined among many scheme to meet requirements of the design, and the required expenses is the smallest(such as weight, area, volume, stress, expenses, etc)that is the optimal designing scheme is the most effective solutions. The optimal designing method provides reliable reference for designing excellent performance crane.
Optimization Design of Hydraulic Cylinder Based on ANSYS
Authors: Han Yi Lun , Huang Li Jun , Wen Xue Lei
Published: September 2012

The basic structure of the piston hydraulic cylinder was introduced. A three-dimensional model was carried out for the hydraulic cylinder by using Pro/E soft，the finite element analysis to the largest hydraulic condition while hydraulic cylinder working by using ANSYS soft，and the distribution of the stress and strain of hydraulic cylinder was derived from it. It optimized the structure of hydraulic cylinder effectively and the cost was saved.
Prediction of Weld Bead Geometry for Robotic GMAW Rapid Prototyping & Manufacturing
Authors: Yin Zi Qiang , Zhang Guang Jun , Zhao Hui Hui , Guo Ning , Jia Chuan Bao
Published: September 2012

This paper concentrates on direct rapid prototyping and manufacturing (RP&M) of functional metallic parts. Robotic gas metal arc welding (GMAW) is employed in this “Slicing & Stack” principle RP&M system. It is indicated that surface smoothness is a critical factor to affects the performance of RP & M products. In order to improve surface smoothness of product, the RP & M system must decrease stack error during stacking in each layer. This investigation establishes relationships between welding parameters and weld bead geometry. First, a rational welding parameters range is determined according to preliminary experiments. Then, quadric orthogonal regression rotational combination experiments scheme is proposed to predict width and height of weld bead. The width and height in regression results are expressed in the form of quadratic equations by welding parameters. Significance test results show that the two quadratic equations are both significant. According to the established relationships, users can easily predict width and height of weld bead when welding parameters are given. Whereas when the given condition is weld bead geometry, optimum welding parameters can also be determined by importing boundary condition according to users’ requirement or the service environment of parts. Experiment results indicate that prediction errors of width and height are both less than 3%.
Size and Defect Detection of Hami Big Jujubes Based on Computer Vision
Authors: Ma Ben Xue , Qi Xiang Xiang , Wang Li Li , Zhu Rong Guang , Chen Qin Gang , Li Feng Xia , Wang Wei Xin
Published: September 2012

In order to realize the rapid nondestructive testing for Hami Big Jujubes’ quality detection, a detecting system based on computer vision was established to detect Hami Big Jujubes’ size and defect. The image grabbing card and CCD camera were consisted of the hardware system, which was used to collect image data. Visual Basic6.0 and image processing toolbox of Mil9.0 constituted the software system. The function of MIL9.0 was called in the Visual Basic6.0 to realize the detection. During image processing, the threshold was all chose (0.1,0.7).Many methods were used to identify the features rapidly and get the H value’s mean and variance, such as colour space transformation, mathematical morphology processing and mask etc. Experimental results showed that the correlation coefficient between the projective areas and weights was 0.945.The correlation between projective areas, transverse diameter and vertical diameter was 0.951.The defects grading models were built by BP neural network .The discriminating rate was as high as 99.16％ in training set，and 91.43％ in prediction set. The average testing time was 80 milliseconds, which can satisfy the detection system’s requirements of time．
Frame Structure Bridge Design CAD Software Systems
Authors: Li Jia Wen , Chen Xu , Li Bang De
Published: September 2012

After the railway speeding-up, a large number of railway level-crossing has changed to the underpass or overpass type of structure. In the underpass type of structure, the most of structure take the underpass bridges or frame bridge structure. This paper put forward the level-crossing rebuild into the frame structure bridge method of design, through using the object-oriented program design method realizes the frame structure bridge automatic design analysis，calculation and drawing process, greatly enhancing the frame structure bridge design work efficiency, accelerating the changing level crossing to grade rate, and eliminating the safety trouble of crossings.
Design and Research of Shell-Breaking Machine for Hand-Stripping Hickory-Nut
Authors: Cao Cheng Mao , Zhu De Quan , Jiiang Qing , Jiang Jia Wu , Li Bin
Published: September 2012

This paper introduced the design process of shell-breaking machine for hand-stripping hickory-nut. Hand-stripping hickory-nut is an instant snack food. Like peanut, it’s easy to separate kernel from shell. The paper compared methods of shell-breaking nuts which is in common use, got inspiration from manual process and absorbs useful experience of traditional processing techniques combining with impact method. Then the mechanism of striking shelling in the way of mechanical knocking is designed. The design of robot percussion arm mechanism, feed mechanism, force regulating mechanism and principle prototype were proposed. The hemispherical grooves are approximately half spherical, which match the shape of hickory-nut. And then the component strike force can be reasonably reduced. The experiment results showed that the machine have good effect in shell-breaking for the Hickory-nut of different specification. Hickory-nut is not convenient to eat because the nuts are deeply embedded in the spaces formed from the hard shell. Hence, special tools are usually needed such as Hickory-nut clamp. Recently years, the hand-stripping hickory-nut is popular in the market. It is an instant snack food. As peanuts, it needs to separate kernel from shell while eating. The traditional processing method is to put it in the special mold and then strike it with the special hammer. But the productivity is low and it will produce secondary pollution easily. Besides, shortage of labor will lead to short supply. Thus mechanized production has become our urgent demand.
Gear Pitting Corrosion Fault Diagnosis Based on Local Mean Decomposition
Authors: Chen Ya Nong , He Tian , Xiao Deng Hong , Cui Hai Tao
Published: September 2012

The local mean decomposition (LMD), a new adaptive time-frequency analysis method, is the research focus in the fault diagnosis field in recent years. In this paper, the LMD’s characteristics are obtained by processing multi-component frequency and amplitude modulation signal, which are usually used to describe the gear pitting corrosion fault signals. Base on the simulation analysis, LMD is presented to deal with the vibration signals of gear pitting corrosion fault, comparing with traditional method. The results show that the gear pitting corrosion defect can be diagnosed by LMD effectively, and LMD can eliminate the false composition effect, thus improving the accuracy of gear fault diagnosis.
Kinetic Study for Ion Exchange of Taurine on D290 Anion Exchange Resin
Authors: Song Feng , Zhuang Shu Juan
Published: September 2012

The kinetics of ion exchange of taurine on D290 anion exchange resin was investigated. The uptake curves of taurine on D290 anion exchange resin were determined in batch stirred tanks, and the diffusion coefficient and the mass transfer coefficient were computed, and the effects of stirred velocity and experimental temperature on the rate of uptake of taurine on D290 resin were discussed. The results showed that with the experimental temperature and the stirred velocity increasing, the rate of uptake of taurine on D290 anion exchange resin increase. And with the increase of the experimental temperature, the diffusion coefficient and the mass transfer coefficient increase .With the increase of the stirred velocity, the diffusion coefficient increase and the mass transfer coefficient don’t be affected. Based on the Helfferich number of this system, the mass transfer process of taurine taken up on D290 resin is dominated by the film diffusion.
A Novel 5-Axis Machining Method for Sculptured Surface
Authors: You Si Kun , Liu Xiao Chu , Deng Hong Guang , Liu Jun
Published: September 2012

In this work, a novel method for sculptured surface subdivision to improve the machinery’s ability and efficiency in 5-axis CNC machining complex surface is introduced. The method subdivides automatically a monolithic convex or concave or simultaneously complex sculptured surface into a number of surface patches and achieves the goal of similar normal directions and small difference between the curvatures in every patch by using weight fuzzy cluster algorithm which takes the curvatures and normal vectors of the sculptured surface into account simultaneously. The inclination angle variation between every two Cutter Contact Points (CC Points) is decreased in every patch to avoid large-angle rotation of tool to save machining time when a flat-end mill is used. This work contributes to automated 5-axis CNC tool path generation for sculptured part machining and forms a foundation for further research.
Computer Aided Programming for Boring Counterbore Holes
Authors: Liu Li Wei , Zhao Xian Zhong
Published: September 2012

In this paper, a method of CAP(Computer Aided Programming) for boring counterbore holes was presented. According to the engineering drawings and the given diameter of holes, the position of holes can be determined automatically. Based on the type of tools, the depth of counterbore holes, the depth of pre-manufactured holes and cutting parameters, the program of boring was generated automatically. Following the program, the process system can complete the rough boring, the finish boring, dwelling or without dwelling at downhole.
Prototype Stress Test Research on Cast-Steel Joint of Large Span Roof System
Authors: Zhang Zheng Dao , Fei Wen Ping , Zhang Jian Mei
Published: September 2012

For the cast-steel joint of large span roof system, the main difficulties of prototype stress test encountered are the large scale of the structure system, large loading system and large supporting system, etc. The hydraulic jack of high tonnage is adopted to apply the load. The frame structure of channel steel is used to fix the cast-steel joint and the loading system. The reverse loading system is elaborated to simulate the axial tensile force. So prototype stress test on the cast-steel joint of large span roof system is accomplished successfully. The test results show that, under the designing load condition, cast-steel joint is in a linear elastic state, the structure is globally safe; the maximum surface stress of cast-steel joint is adjacent to the crossing point of steel pipes; the stress value of test is well coincident with one of finite element analysis. This test device system is especially suitable for the stress state test of large components, and can also provide important reference to the similar projects.
A Novel Dynamic Electromagnetic Heating-Magnetizing Device Used for Reverse Osmosis System
Authors: Du Hai , Qu Yan Bin , Cheng Shu Kang
Published: September 2012

A novel, environmental friendly dynamic rotating electromagnetic heating-magnetizing device is proposed, which can heat up and magnetize the low temperature feed water of reverse osmosis system. The device converts input mechanical energy into heat energy completely. The structure and operation mechanism are discussed in detail, and the mathematical model of loss is established based on fundamental electromagnetic field theory. At last, the effects of water magnetization treated by the device are introduced, which inhibits scaling on the reverse osmosis membrane surface and slows down the corrosion of metal surface.
Machining Deformation Equation of FWP Based on Rayleigh-Leeds Method
Authors: Deng Yao Hua , Liu Gui Xiong
Published: September 2012

This paper discusses the FWP bending deformation processing computing problems. Using Rayleigh-Leeds method to solve the flexible part bending deformation. Designing flexible part bending deformation test function. Finding out the flexible part itself material characteristics, the relationship between Fz and deformation through satisfying FWP processing process of a flexible minimum potential energy conditions to work out the approximate solution of the flexible part bending deformation. Finally, think a rectangular flexible workpiece that made of polyurethane sponge as an experiment subject. The results show that the calculated results of the average of the relative deviation are only 6.85%. Proof that this bending deformation test functions satisfies the actual deformation calculation requirements.
Structural Research of Pipe Automatic Handing System of Land Rig
Authors: Sha Yong Bai , Zhu Ji Liang , Zhao Xiao Ying , Wan Xiao Peng
Published: September 2012

Pipe automatic handing system is an important part of automation rig, which replace manual operation by using mechanical equipment, and realize the reciprocate transfer operation of drill pipe. It is an effective way to make drilling safe, healthy and efficient. This paper introduces the common structure, the function and the basic principle of the pipe automatic handing system used now, and the different structure are compared.
An Experimental Investigation of Ultrasonic Assisted Grinding in DOE Approach
Authors: Kim Kyeong Tae , Hong Yun Hyuck , Park Kyung Hee , Choi Young Jae , Lee Seok Woo , Choi Hon Jong
Published: September 2012

In this work, grinding test was performed in terms of machining parameters, such as grinding speed, feed rate, etc., in order to study effect of ultrasonic vibration in grinding. The design of experiment (DOE) approach was used for an optimal condition of ultrasonic assisted grinding, which can minimize the grinding forces. In DOE, ultrasonic amplitude power, feed rate, and rotation speed of spindle were chosen as the major machining factors. The grinding forces were measured and compared between the conventional grinding and ultrasonic assisted grinding. From the experiment, it was found that the grinding forces decreased as the ultrasonic vibration power and the rotation speed of spindle increased while the grinding force was reduced as the feed rate increased. In addition, regression model was formulated for obtaining optimal grinding condition.
Genetic Programming for Grinding Surface Roughness Modelling
Authors: Chen Xun , Alabed Asma
Published: September 2012

Grinding process is commonly selected for finishing operation because grinding has high accuracy and surface finish with a relatively high material removal rate. One of the most common issues in grinding process planning is to determine grinding condition for required surface roughness. This paper presents a feasibility study on grinding surface roughness modelling using genetic programming (GP) method. It has successfully demonstrated that GP could provide reliable prediction and has advantages over other established methods in terms of dealing with missing data during modelling process.
Research Progress of On-Line Measurement and Compensation Technology about Grinding Wheel Wear
Authors: Liu Wei , Deng Zhao Hui , Wan Lin Lin , Tang Hao
Published: September 2012

According to the characteristics of grinding wheel wear in the grinding process, the grinding wheel wear forms and their reasons are analyzed. At the same time, as the grinding wheel wear will affect the size of components, the procedures of on-line measurement and compensation technology about grinding wheel wear are summarized. The current domestic and international research status of on-line measurement and compensation methods about grinding wheel wear are introduced, such as position calibration based method, machine vision based method, laser displacement based method, acoustic emission based method, grinding force based method, cutting vibration based method, grinding acceleration based method and pressure based method. Finally, the current research difficulties of grinding wheel wear’s on-line measurement and compensation technology are analyzed, and the further research direction is made.
Performance of Newly Developed Single-Point Diamond Dresser in Terms of Cutting-Point Rake Angle
Authors: Mochida Yasushi , Kubo Akihiko , Tamaki Jun’ichi , Harano Katsuko , Sumiya Hitoshi , Ullah A.M.M. Sharif
Published: September 2012

A cutting-tool-type single-point diamond dresser, the tip of which has a given rake angle, was developed and its dressing and grinding performances were investigated. It was found that the dressing mechanism changes its mode from a ductile mode to a brittle mode with increasing back rake angle in the negative direction and that the cutting-tool-type dresser exhibits good robustness owing to the fact that its ground surface roughness is not markedly affected by the dressing conditions.
Preliminary Studies for Precision Polishing of Micro Structured Mold by Using Three-Dimensional Low Frequency Vibration Utilizing Piezoelectric Actuator Incorporated with Mechanical Amplitude Magnified Mechanism
Authors: Chee Sze Keat , Suzuki Hirofumi , Uehara Junichi , Yano Takeshi , Higuchi Toshiro
Published: September 2012

Precision polishing of micro structured mold has been highly demanded due to the increasing demand for optics manufacturing such as solar optics and DVD pick-up system, and medical devices like μ-TAS [1-5]. These micro structured molds usually have complicated structure and need to be polished after grinding or cutting. In this paper, a three-axis low frequency vibration (3DLFV) polishing actuator is proposed. The actuator consists of 3 multilayers-stacked piezoelectric actuators (PZT) incorporated with mechanical amplitude magnified mechanism. The mechanical amplitude magnified mechanism utilizes mechanical structures which is also called mechanical transformer, which is capable to elongate the stroke of the piezoelectric actuator to almost 13 times to 225 m. By driving the PZT in sine wave with particular phase different, dual direction trajectory such as circle can be achieved, and is proved to be effective in precision mold polishing [8]. With the 3DLFV actuations, polishing tool with polyurethane is actuated to stir the diamond slurry to achieve polishing effects. In polishing experiments, nickel-plating metal used as work pieces are polished with diamond slurry and the polished depths are measured. As a result, three-axis low frequency vibration (3DLFV) is proposed and developed. Its capability in polishing precise mold is studied and confirmed to be efficient. In order to improve the work piece surface, a dwell time control method can be applied with the 3DLFV.
Influence of Polishing and Pressing Force on the Material Removal Rate in Fixed Abrasive Polishing with Compact Robot
Authors: Niwa Masaki , Ogawa Sachiko , Hirogaki Toshiki , Aoyama Eiichi , Onchi Yoshiaki
Published: September 2012

To help reduce the environmental impact of abrasive polishing, we have investigated the use of a compact robot and fixed-abrasive polishing. We used a five-joint closed-link compact robot with a fine diamond stone on its main axis to polish the glass plate and measured the polishing pressure(=pressing force/stone constant area), the polishing force, and the material removal rate. From these results, we investigated the relationship between the polishing pressure and the polishing force and between the polishing pressure and the material removal rate. We found that there is an interesting relationship between the polishing pressure and polishing force, which is not simply proportional but exponential, that the friction coefficient(=polishing force/pressing force) increases as the polishing pressure increases, and that by focusing on the friction coefficient, we can estimate the material removal rate.
The Key Technologies and Advances of Ultra-Precision Single-Plane Polishing and Lapping Devices
Authors: Li Qing Jian , Wang Cheng Yong , Zheng Li Juan , Wang Yu Jia , Song Yue Xian
Published: September 2012

Some technologies of ultra-precision single-plane polishing and lapping devices, including spindle section, polishing pad, cooling system, dressing system and pressurization system are discussed. The development trends of ultra-precision single-plane polishing and lapping devices are also analyszed as more controllable, integrated and high-precision in the future.
Experimental Study on Polishing Properties of Silicone Oil Based Magnetic Compound Fluid
Authors: Yin Shao Hui , Cheng Zhen Yong , Xu Zhi Qiang , Chen Feng Jun , Yu Jian Wu
Published: September 2012

Silicone oil based magnetic compound fluid was prepared to polishing stainless steel in this paper. The new fluid consists of nano-sized magnetite particle, micro-sized diamonds, micro-sized iron particle and α-cellulose. The characteristics of the fluid were analyzed. The length and quality of the magnetic cluster in the compound fluid was observed under a magnetic field. Polishing experiment of stainless steel was conducted using the silicone oil based magnetic compound fluid on an inclined polishing finishing device. The micro morphology of the stainless steel’s surface was measured. The results showed the surface quality was improved remarkably and the final roughness of the surface was Ra (Average roughness) 0.020μm.
Simulation of 1D Abrasive Vibratory Finishing Process
Authors: Kumar Prakasam Pradeep , Sathyan Subbiah
Published: September 2012

The vibratory finishing process involves three dimensional motion of abrasive media interacting with part surfaces. With the ultimate goal of simulating such media motion in laboratory conditions, we present here a first step that makes use of a tribometer’s recipricating drive to provide one dimensional controlled vibrations. Finishing experiments using this setup are conducted using abrasive media and titanium alloy work material, both of the type typically used in aerospace industry. Material removal rates, surface roughness and contact forces are measured in two different setups. The media motion is also modelled using multi-body dynamics to predict the contact forces between the media and the work surface. Experimental results are seen to follow literature reported and model predicted trends. This work paves the way for a true three dimensional simulator for a vibratory finishing process.
Ultrafine Surface Finishing of Fused Silica Glass Using MCF (Magnetic Compound Fluid) Wheel
Authors: Wu Yong Bo , Jiao L. , Guo Hui Ru , Fujimoto M. , Shimada K.
Published: September 2012

This paper aims to develop an alternative novel technique for the high efficiency and ultrafine surface finishing of fused silica glass. A semi-fixed abrasive tool named MCF (magnetic compound fluid) wheel is produced by distributing a certain volume of MCF slurry uniformly over the whole circumference surface of ring-shaped permanent magnets. An experimental rig is constructed in house followed by experimental investigations involving effects of the MCF wheel construction and process parameters on the material removal and work-surface roughness. As a result, the performance of the developed MCF wheel in the surface finishing of fused silica glass has been confirmed, and the appropriate wheel construction and process parameters have been determined in terms of the material removal rate, the flatness of polishing area and the surface roughness, showing an extremely smooth work-surface with surface roughness of Ra0.92nm has been achieved successfully in the current work.
Research on the Workpiece Kinematics in Face Lapping with Friction Drive
Authors: Heisel Uwe , Jakob Philipp
Published: September 2012

In face lapping, the achievable material removal rate and surface quality depend strongly on the workpiece kinematics. Hence, the precise knowledge of the kinematics is an important requirement for increasing the efficiency and quality of the superfinishing process. The main focus of experiment is to identify how different workpiece geometries influence the resulting kinematics. The process kinematics in face lapping with friction drive is performed by means of motion tracking. Multi-body simulation allows extending the understanding of the process. Apart from the motion patterns of the lapping process, which were determined before, experimentally established reaction forces are used for verifying the considered rigid body model. A deviation of less than 10 % between the forces determined experimentally and by simulation verifies that it is a promising possibility to assess the kinematics by simulation.
Slurry Flow Visualisation of Chemical Mechanical Polishing Based on a Computational Fluid Dynamics Model
Authors: Tian Y.B. , Lai S.T. , Zhong Z.W.
Published: September 2012

In this work, we developed a computational fluid dynamics (CFD) model to simulate the slurry flow between the wafers and pad during the chemical mechanical polishing (CMP) process under a multiple-wafer configuration. A serial of simulations were carried out to visualise slurry flow and explore the effects of the process variables concerned on the flow velocity and pressure distributions beneath the wafers. Through the model and simulation, the flow field characteristics were obtained and analyzed under different operating conditions. The results can provide an insight into a fundamental understanding of the slurry flow behaviours under the multiple-wafer configuration and some useful implications for the selection of practical polishing variables.
Simulation of CMP Process Based on Mixed Elastohydrodynamic Lubrication Model with Layered Elastic Theory
Authors: Zhou Ping , Kang Ren Ke , Jin Zhu Ji , Guo Dong Ming
Published: September 2012

A simulation framework based on the mixed elastohydrodynamic lubrication (mixed EHL) model has been used successfully to explain some phenomena observed in Chemical mechanical polishing (CMP) process. However, the pad deformation model adopted in various CMP simulation frameworks, such as Winkler elastic foundation model or elastic half-space model, can not correctly describe the deformation features of pad, especially at the wafer periphery. In this study, a layered elastic theory, which can calculate the pad deformation with similar accuracy but lower computational cost than 3D finite element method (FEM), is introduced into the mixed EHL, and it is significant to predict the contact pressure distribution more accurately than existing approaches. Further, the material removal rate can be predicted accurately, it is useful for the study of the mechanism of CMP and the optimization of the CMP processing parameters.
Development of a Vitrified Bonded Superabrasive Wheel with Electrical Conductivity and its Application
Authors: Iwai Manabu , Kazui Yuya , Ninomiya Shinichi , Suzuki Kiyoshi
Published: September 2012

A vitrified bonded diamond wheel having electrical conductivity was manufactured on a trial basis. The electrically conductive (EC) vitrified bonded diamond wheel has enabled an electrodischarge truing and an electrical contact sensing. In this study, the EC vitrified bonded diamond wheel is applied to the EDM (Electro Discharge Machining) assisted grinding of PCD materials. The result shows that a lower and more stable grinding force can be realized and a better surface finish is attained compared with those achievable with a metal bonded diamond wheel.
The Effect of Abrasive Water Jet Process Variables on Surface and Subsurface Condition of Inconel 718
Authors: Escobar-Palafox Gustavo A. , Gault Rosemary S. , Ridgway Keith
Published: September 2012

Experiments were carried out in Inconel 718 in order to investigate the effect of abrasive water-jet process variables on surface and subsurface condition. A Design of Experiments (DoE) approach was taken, considering variables such as water pressure, traverse rate, abrasive mass flow rate and abrasive grit size. The experimental variables were related to taper ratio, surface roughness of different zones in the machined surface and subsurface condition (deformation and crater depth). Statistical analysis was carried out in order to develop mathematical models which include process variable interactions and quadratic terms. This led to models with high correlation and prediction power which allow a better understanding of the process and can form the base for further process optimisation. The models were validated with additional experiments and showed good agreement with the water jet system. The results showed that water pressure has a nonlinear behaviour in the quality of the surface and sub-surfaces and that interaction between the variables had a significant effect on the quality of the surfaces and sub-surfaces generated by the AWJ.
Effects of Ultrasonic Vibrations Given to an Electrode on the EDM Performance in Processing PCD
Authors: Suzuki Kiyoshi , Takada Takuya , Zhou Zhi Rong , Okamichi Takuya , Iwai Manabu , Ninomiya Shinichi
Published: September 2012

EDM machinability of PCD was investigated using a copper electrode giving ultrasonic vibrations. In this series of EDM experiments, three types of ultrasonic vibration modes were selected (axial vibration, flexural vibration and complex vibration). From the experimental results, it was found that EDM efficiency became 3 times higher than the ordinary EDM (no vibration given to the electrode) under the two specific vibration modes, namely, 1) the axial vibration (large) mode and 2) the complex vibration (axial vibration: large + flexural vibration: small) mode. Furthermore, it was shown that the effects resulted from not only the cavitation effect of the working fluid but also the vibrational action of the electrode itself.
Fundamental Study on Setting of Diamond Abrasive Grains Using Electrostatic Force for Single-Layered Metal Bond Wheel
Authors: Ohashi Kazuhito , Kawasuji Yusaku , Shinji Yoshifumi , Samejima Yoshitaka , Ogawa Soma , Tsukamoto Shinya
Published: September 2012

Single-layered metal bond diamond wheels are useful to high efficient grinding of difficult-to-grind materials because of the high gripping force of abrasive grains and the controllable grain density. In this paper, fundamental information are obtained for an application of electrostatic force to setting of diamond grains into pasted metal bond slurry layer on wheel surface, investigating experimentally jumping phenomenon of diamond grains in an electrostatic field between a electrode plate and metal bond slurry layer. The SD grains and the SDC grains coated with Ti are selected. SDC grains jump into a metal bond layer as quick as making an electrostatic field, however SD grains jump with short time lags. The setting rate of SDC grains is larger than that of SD grains, and setting position accuracy of SDC grain array is better than SD grain array. The possibility of setting abrasive grains into single-layered metal bond diamond wheel surface using electrostatic force is obtained and SDC grains are suitable to the proposed abrasive setting method.
Surface Finishing of Electrically Conductive Diamond Tools by Electrolytic Machining
Authors: Iwai Manabu , Suzuki Kiyoshi
Published: September 2012

This paper deals with a new surface finishing method of electrically conductive diamond materials by making efficient use of an electrically conductive nature of the workpiece material, instead of conventional methods such as grinding, lapping and polishing using diamond abrasives. The authors focused on the electrolytic machining method and not on the electro discharge machining method for the two advantageous features of the electrolytic machining in addition to the general view that a better surface roughness could be obtained. One of those features is that no higher heat is generated at the machining point. This can eliminate a risk of the film delamination in the case where a workpiece is the CVD diamond coated tool. The other is that a wider machining gap is available between an electrode and a workpiece. This was thought to allow the electrolytic machining to be applied to a tool with a complex shape such as a drill and an endmill. Based on these concepts, electrolytic machining experiments were conducted on the electrically conductive diamond materials. From the results, it was found that the surface of the electrically conductive diamond could be smoothened enough by electrolytic machining though relatively long period of time was required.
Modeling the Property Variation of Diamond Composite and its Impact on the Reliability of Cutting Tools
Authors: Sun Yong , Li Xing S.
Published: September 2012

Picks are commonly used cutting tools for mechanical excavation. Diamond composite is replacing tungsten carbide as cutting tips of the picks in hard rock cutting. Tips made of Thermal Stable Diamond Composite (TSDC) have high potential for improving tool life because of its high wear resistance, high hardness, high compressive strength and high thermal stability. However, as TSDC is a type of new material, the technology for its production is still unstable, which often results in considerable variations in the material properties of cutting tips. These variations can significantly affect the optimization of tip design. The conventional design approach based on mean values or extreme values cannot effectively optimize the design of cutting tip due to over or under-estimation of tip failure risks. To address this issue, in this study, a probabilistic approach is proposed to model the property variations of TSDC tips and estimate tip failure risks under a given operational circumstance using reliability theory. The new approach enables designers and operators to estimate the failure risks of cutting tips with a specified confidence level.
Cutting Forces and Tool Wear in Dry Milling of Ti6Al4V
Authors: Chen Yun , Li Huai Zhong , Wang Jun
Published: September 2012

Titanium alloys are difficult-to-cut materials. This paper presents an experimental study of the effects of different cutting conditions and tool wear on cutting forces in dry milling Ti6Al4V with coated carbide inserts. The experimental results show that the peak forces increase with the increase in the feed rate and depth of cut. With the cutting speed increment in the range from 50 m/min to 150 m/min the peak forces decrease, while at further higher cutting speeds investigated peak forces increase. The decrease of the peak forces is due to thermal softening of the workpiece material and the increase is because of the strain hardening rate of Ti6Al4V. The tool wear experiment reveals that the major tool wear mechanism is the flank wear. The variations of the peak forces are caused by both the tool wear propagation and the thermal effects.
Research on the Drilling Temperature Field Model of the Unidirectional Carbon Fiber Epoxy Composites
Authors: Zhu Guo Ping , Bao Yong Jie , Gao Hang
Published: September 2012

Heat is easy to aggregate during drilling carbon fiber epoxy (C/E) composites because of the materials’ anisotropy and the low thermal conductivity. It can result in a high temperature gradient which has a significant effect on the quality of the workpiece and the tool wear. In this paper, a drilling temperature field model of the unidirectional composites is developed. Based on the finite difference method (FDM) the temperature distribution and changes are simulated. Experiments of measuring the drilling temperature at the exit of the hole are carried out, and the results show that the temperature distribution is in agreement with the temperature field model.
Review of Microelectrode Fabrication
Authors: Liu Pei Chao , Zhou Jun , Li Shou Lei , Ma Hong Ming
Published: September 2012

With the development of electrode technology and deepening research on bio-medical discovery, various micro-neuron probes have been designed and manufactured. Electrodes, a carrier of stimulating and recording neuron signals consists of the main part of probe. In the last ten years, as the micro-manufacturing technology constantly develops and creates, the electrode structure has been integrated onto a new level. The article will give a compound conclusion on the manufacture methods of the main electrode types in the course of development.
Basic Study on Micro V-Groove Cutting of Tungsten Carbide Using Diamond Tools
Authors: Kitajima Takayuki , Okuyama Shigeki , Yui Akinori
Published: September 2012

Micro V-groove cutting of cobalt-free tungsten carbide using two types of V-shaped diamond tools is performed using mist of zinc dialkyl-dithiophosphate (ZnDDP) as lubricant. The two types of tool tested are 1) mono-crystalline diamond and 2) poly-crystalline diamond made of approximately 30 nm-sized diamond crystals. The geometry of the V-groove-cutting process is theoretically investigated and the relationship between V-groove angle, original rake angle, and effective rake angle is clarified. Through the cutting experiments, the effects of diamond types and rake angle on tool-wear characteristics are explained. When rake angle is set at zero degrees, tool chipping frequently occurs for both types of diamond tools even when ZnDDP is supplied. However, when rake angle is set at -30 degrees for poly-crystalline diamond, tool wear is minimized.
Estimation of the Grinding Time by Means of the Grinding Process Model
Authors: Yamada Takazo , Lee Hwa Soo , Miura Kohichi
Published: September 2012

In grinding operation, elastic deformations of the grinding machine and the grinding wheel induce a residual stock removal of workpiece. On the other hand, thermal expansions of the workpiece and the grinding wheel increase the depth of cut. Therefore, calculation of a ground depth of cut and/or the grinding time has to be considered by the elastic deformations and the thermal expansions. From such a viewpoint, in this study, grinding process model taking into account the elastic deformations and the thermal expansions was proposed. This paper aims to estimate the grinding time by means of the proposed grinding process model.
Mechanical Properties and Deformation of LiTaO3 Single Crystals Characterised by Nanoindentation and Nanoscratch
Authors: He An Shun , Huang Han , Zhou Li Bo
Published: September 2012

This paper reports our recent results on the nanoindentation and nanoscratch of LiTaO3 single crystals. The elastic modulus and hardness of LiTaO3 obtained from nanoindentation were 251±3 GPa and 12.6±0.6 GPa, respectively. During indenting, pop-in events occurred when indentation load was in the range from 305 to 640 μN. Incipient kink bands (IKBs) were believed to be responsible for the pop-ins. Nanoscratching showed that there existed a threshold normal load of 2.5 mN, above which cracks were generated and the material removal was in the brittle regime. The knowledge gained is valuable to the design of an effective machining process for LiTaO3 crystals.