bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Liquid-Solid Two Phase Abrasive Flow Based on the Unified Second-Moment
Authors: Ji Shi Ming , Gong Bin , Tan Da Peng , Yuan Qiao Ling
Published: March 2010

According to liquid-solid two-phase flow model for the complexity of adaptation, as well as the impact of the concentration of particles, and we put forward a new method of considering the turbulent influence of particle concentration. Basing on the different turbulent control methods of the liquid-solid two-phase flow, we established the unified second-moment turbulence model. Using fluent software can realize turbulence model considering the particle pressure’s influence on particle’s concentration, and solve the problems of particle concentration and the flow passage control method. The simulation results showed that considering the concentration of particle’s influence on the pressure of the solid phase can accurately express the model of liquid-solid two-phase turbulent flow pattern.
Study on the Fluid Magnetic Abrasive Polishing Technology
Authors: Lu Cong Da , Gong Xiao Jun , Jia Hong , Chai Guo Zhong
Published: March 2010

Fluid magnetic abrasive (FMA) is a new precision finishing process. It has the capability of processing free shape surfaces and complex cavities. Due to its strong adjustability and controllability, FMA could be regarded as the final process of machining which could greatly improve the surface quality of workpiece. The paper first introduces the component and machining mechanism of FMA, secondly it describes the model of the material removal in the process, thirdly it presents the devices of FMA polishing. At the end, a grinding head tool based machining mode is proposed for realizing the polishing of internal cavity.
Structure Analysis on Gantry Machining Center and Characteristic Analysis of Rolling Guide Interface
Authors: Zhang Zheng Wei , Jin Chu Yun , Zhang Jian Run
Published: March 2010

Multi-point impulse tests, which could determine the transfer function of each point, were carried through on vertical and horizontal direction of sphericalguide-slider joint surface by DATRAN dynamic analyzer. Multi-point impulse tests could determine the transfer function of each point. In order to determine the single-DOF mode of the sphericalguide-slider joint surface, the top surface and one of the flanking surfaces of the sliding block were selected as test-object. When the amplitude of each point on the same surface is mainly equal with each other, the corresponding mode could be judged to be single-DOF mode. The experiment conclusion would be a foundation for the future dynamic simulation.
Constitutive Relationship of TA15 Alloy and its Application in the Hammer Forging Process Simulation
Authors: Quan Guo Zheng , Tong Ying , Zhang Yan Wei , Zhou Jie
Published: March 2010

A Kumar-type constitutive relationship of TA15 alloy was investigated by non-linear regression analysis, and the equations were established based on test data from hot process simulator. Applying this constitutive equation in commercial FEM software of SFTC/Deform, the hammer forging process of TA15 alloy beam was simulated, meanwhile the final shape of forging piece, the hammering times, the height reduction variation and the maximal effective stress variation along with forging time were predicted. The hammer forging test was carried out and the test results showed that the simulation based on Kumar-type constitutive relationship meet the practical need to a great extent.
NC Reconstruction of High Accuracy Spheres Grinding
Authors: Yu Ying Liang , Miao Zhi Yi , Yu Hui
Published: March 2010

The design of NC reconstruction of a machine tool and the parameters conversion are elaborated by means of an example of sphere grinding using a common grinding machine which has been reconstructed by special NC technologies. The grinding of a large size sphere is realized by using the linear instruction. The variable speed rotary grinding of a large size sphere is realized by using the arc instruction. The instantaneous compensation of the grinding wheel is realized by using the screw instruction. The function and application scope of NC technology are expanded because of variable speed rotary motion and instantaneous compensation of the grinding wheel.
Tool Path Generation Method of Equal Approximation Error for Free-Form Surface in High Speed Machining
Authors: Zhou Chun Jiang , Chen Hong Chun
Published: March 2010

The development of surface high-speed machining has put forward higher demands for uniform cutting load and smooth cutting tool path. Most current tool-path planning methods are based on constant scallop height, but they have the disadvantage of path point redundancy during the path discretization process. To overcome the problem, a tool path generation method of equal approximation error in each step for free-form surface is presented based on geodesic principle and curvature judgment. In this method, the NURBS curve is employed to realize smooth transition for adjacent two tool paths in high-speed machining. A certain angle of inclination of flat-end milling cutter during multi-axis machining improves the machining efficiency. Because of the advantage of this machining condition, the cutter location point generation algorithm during the machining condition is given by the method. The method is verified and simulated by C++. Experiment results proved that it can obtain uniform cutting load and continuous smooth cutting tool path during surface high-speed machining by the proposed method.
Path Generation and Posture Angle Control of Tool for Robotic Polishing System
Authors: Ying Shen Shun , Ji Shi Ming , Jin Ming Sheng , Zhang Li
Published: March 2010

To improve the quality and efficiency of the finish, industrial robots are used to polish the workpiece cavities with complex shapes. This paper presents key technologies of robotic polishing system including path generation, tool orientation control and G-code converting. Robot path data is generated automatically from the NC data, and tool posture angle is superadded to the robotic polishing path according to the requirement of the robotic polishing technology. Specialized software is developed to automatically generate a program, which includes the path data and tool posture angle, and this program is uploaded to the robot controller for the die polishing process.
Statistical Analysis on Lapping Parameters for Sapphire Wafer
Authors: Wu Hao , Gao Peng Fei , Wang Wei Fang , Wen Dong Hui
Published: March 2010

Effect of lapping speed, plate material and crystal orientation on material removal rate and surface roughness were investigated by experiments and Taguchi Methods. Experimental results show both materials remove rate and surface roughness could be finished by using sythetic copper lapping plate with w3.5 cubic boron nitride abrasive than that for thin plate. Materials removal rate and surface roughness have no much difference for different crystal orientation as A-plane, C-plane and M-plane with experimental parameter conditions, lapping speed would be recommonded to not over 40rpm.
Layer Face Milling Cutter Parametric Modeling and Modal Analysis
Authors: Ji Sheng Yuan , Liu Xian Li , Yan Fu Gang , Yue Cai Xu , Zhao Xing Fa
Published: March 2010

Performance-based parametric design method for improving the face milling cutter design efficiency and ensuring the use of performance has an important significance. Three kinds of parameter design method are described in this paper, and parametric design of series of layer milling cutter is completed by modeling parametric design method with UG software. Also, modal analysis is made with FEM. Therefore the study results provide examples for optimization of tool structural and analysis of restrain vibration.
Study on the Cutting Deforming Force of Single Abrasive Grit for Ultrasonic Vibration Assisted Grinding along Normal Direction
Authors: Zhang Hong Li , Zhang Jian Hua
Published: March 2010

Based on the kinematics analysis and the cutting depth calculation of single abrasive grit, the mathematics models of the cutting deforming force and the average cutting deforming force were made by introducing the unit grinding force, Fu. And the formula of the average cutting force during the grinding zone was calculated. The experiments on the grinding force ratio were conducted under conventional grinding(CG) mode and normal ultrasonic vibration assisted grinding(NUAG) mode. The results showed that the unit grinding force in NUAG was lower than that in CG under the same machining condition; the grinding force ration was decreased due to the normal ultrasonic vibration of the workpiece. And it was helpful to improve the machinablity of the hard-brittle material.
Crossbeam Analysis and Structure Optimization of Special-Shaped Stone Combined Machining Center
Authors: Zhang Ke , Ren Ju Ping , Guo Hua , Wu Yu Hou , Zhao Kai Jun
Published: March 2010

With the increase of the quantity demanded, stone products with high quality, really artsy and diversification become more and more best-selling. The special-shaped stone machining equipments with numerical control, single machine intelligent, high speed, high efficiency and multi-function combination must be manufactured to produce these stone products. In this paper, 3D design and project optimization for special-shaped stone composite machining center are carried by Solid Works and innovative design. Model analysis of the crossbeam in this machining center is carried by ANSYS and the maximum deformation value in the crossbeam is found. The crossbeam structure is optimized by comparison and analysis. The design and manufacture of special-shaped stone combined machining center is very helpful for development of manufacturing.
Study on Characteristic of Abrasives in Chemical Mechanical Polishing of Silicon Wafer
Authors: Su Jian Xiu , Chen Xi Qu , Du Jia Xi , Wan Xiu Ying , Ning Xin
Published: March 2010

In order to understand the material removal mechanism in the process of chemical mechanical polishing (CMP), the states of abrasives in the slurry and on the polishing pad in CMP process have been studied by testing. It was concluded that although the abrasive in the slurry is in the form of agglomeration, but the abrasive on the polishing pad are in approximately uniform layer distribution. The different CMP slurries had been designed for CMP test of MRR. According to analyzing the test results, it was concluded that the mechanical action produced by the abrasive is the main mechanical action in wafer CMP process and the MRR mainly results from the interaction between the mechanical action of the abrasives and the chemical action of slurry. These results will provide a reliable basis for the building of abrasive trajectory model and a theoretical guide to further understanding the material removal mechanism in wafer CMP.
Development of CNC Milling System for NURBS Interpolation Based on IGES
Authors: Li Tie Gang , Fu Chu Lin , Guan Peng , Yu Tian Biao , Wang Wan Shan
Published: March 2010

To improve machining efficiency and accuracy for surface, a method of machining Non-Uniform Rational B-spline (NURBS) surface based on IGES was put forward. The algorithms for surface information processing machining path planning and real time locus interpolation involved in this method have been worked out from the research results. A prototype of the CNC milling system with “PC+PMAC motion controller” is designed by toolpath planning, coordinate transformation and acceleration-deceleration control, which using VC ++ and openGL in Windows NT + RTX system platform. The simulation experiment was conducted to test the effectiveness and accuracy of the proposed method.
Numerical Prediction of Manufacturing Error in Sliding Panel Structure
Authors: Li Zhi Xin , Ji Shi Ming , Lv Xun , Xiong Si Chang , Ying Shen Shun , Wang Yang Yu
Published: March 2010

The present work focuses on the numerical prediction of the manufacture quality of a sliding panel structure, in which the mobile components are floating on the immobile components and the 0.002mm thickness oil-film clearance between the mobile and immobile components. The interaction between them is the interfacial coupling interaction. A single-point spring-damping supporting element is introduced to simulate this type of interaction traditionally, in which the torsion of the mobile components is increasing with the supporting element reduced. To analogy the interfacial coupling interaction, the finite centrality supporting method is introduced to study the thin oil-film effect between the mobile and immobile components. And the manufacturing quality is predicting through the numerical study. Compared with the results derived from the numerical and experiments, the manufacturing error is in accordance with each other.
Study on a Three-Dimension Nanometer Precision Machining
Authors: Lin Hai Bo
Published: March 2010

In ultra-precision cutting, grinding and non-traditional machining, it is difficult to balance long travel and high precision, especially in multi-coordinate machining. Aiming at tri-coordinate ultra precision machining, this paper studies the ultra precision machining technology and theory. It attempts to seek the principle in ultra precision machining as well as construct a pilot antitype with the ultra precision tri-coordinate machining system machine.
Application of Magnetic Abrasive in Gasbag Polishing
Authors: Ji Shi Ming , Chen Guo Da , Jin Ming Sheng , Zhang Li , Yuan Qiao Ling , Zhang Xian
Published: March 2010

Application of magnetic abrasive to the field of finishing processes is increasingly popular and important. Magnetic abrasive finishing (MAF) is effective in precision machining of non-planar workpieces. To study the control of working abrasive morphology and the valid way to solve “incline effect” which is common in some industrial field, application of magnetic abrasive in gasbag polishing is presented. Besides, the polishing system is introduced, and the important factors which influence the magnetic abrasive polishing are studied. Then some tentative experiments are carried out to study its polishing effect. It is found that the difference of surface roughness value and material removal rate under different bevel angle is in small range, which indicates this approach is useful in solving “incline effect”. The work in this paper is also a good attempt for further study that polish precipitous surface of mould or other products.
Hydration Polishing of Sapphire
Authors: Wu Jian Lin , Wang Wei Fang , Gao Peng Fei , Wen Dong Hui
Published: March 2010

This paper discussed the polishing characteristic of single crystal sapphire (0001) when using 100°C vapor as polishing liquid and cedar wood as polishing pad. Surface roughness and scratch were compared before and after hydration polishing process. For 20 hours hydration polishing, both XRD and surface texture show that sapphire surface was changed in micro-structure and texture, even with minor scratch on the hydration polished surface, surface roughness could be decreased to Rt6.74 in X direction and Rt7.64nm in Y direction, it is about 2 nm surface layer was removed during hydration polishing.
Optimization of Molding Process Parameters for the CPU Fan Based on Orthogonal Experiment
Authors: Lu Cong Da , Zhang Yi Lian , Jiang Shao Fei , Chai Guo Zhong
Published: March 2010

In this paper, the main molding process parameters which are relevant to warpage were optimized by orthogonal experiment and finite element software MPI. The result shows that we can get a series of optimized parameters and know how much each process parameter influences the warpage by combining orthogonal experiments with simulation experiments using MPI, while fewer experiments are needed. Verified by MPI, such series of optimized parameters can keep the warpage in a low level and completely meet the standard of the product.
Influence of Grinding Parameters on the Depth and Uniformity of Cylindrical Grinding-Hardened Layer
Authors: Liu Ju Dong , Zhuang Jie Zhen , Zhang Xi Lin , Xu Zhi Long
Published: March 2010

On the basis of the cylindrical grinding-hardening test, the influences of the grinding parameters on surface hardened layer were studied. The result shows that when ap≤0.2mm, there is an unhardened area exist in cylindrical grinding hardened workpiece. When ap＞0.2mm, there is a tempered area exist in cylindrical grinding hardened workpiece due to the action of grinding heat during cut-in and cut-out of grinding wheel. When depth of cut increases, or feed speed decreases, the hardened layer depth increases accordingly. In the practical application, the satisfactory quality of the cylindrical grinding hardened layer can be obtained through reasonable combination of ap and vw.
Ceramic Sample Preparation by Polishing Process for Nano-Indentation
Authors: Sheng Ji Sheng , Wen Dong Hui , Ji Shi Ming
Published: March 2010

Ceramic materials are widely used in the fields of aviation, chemical industry, military, machinery, electronics, so there are so many researches on ceramic materials. This article is mainly about ceramic sample preparation by polishing process for nano-indentation, taking Alumina ceramic and Zirconia ceramic for example. As we know, nano-indentation test is an effective mean to study materials. It is concluded that after polishing, the ceramic surface roughness can reach Ra<10nm and maximum scratches<1nm, flatness<1μm, we can get good quality surface, that well meets the surface requirements in nano-indentation.
The Research in Algorithm for MRF Forming Dwell Time of Optical Components
Authors: Yang Zheng Min , Hu Hong Ping , Gao Yu Bin
Published: March 2010

Magnetorheological finishing technology is a new generation of high-precision optical accessory polishing and processing methods. It presents a MRF dwell time algorithm that can quickly calculate the resident time during magnetorheological processing of the rotational optical parts. A magnetorheological forming polishing experiment on a prototype has been carried out on BK9 glass parts of 20mm rotary symmetrical face shape. The algorithm can improve the surface shape precision of the workpiece from 6.5um to 0.61um. Emulational and experimental results show that the surface shape error of a spherical polished workpiece is convergent by this method, which is also, applies to magneto-rheological finishing of non-spherical and planar workpiece.
Virtual Simulation and Optimization for 5-Axis Milling Process
Authors: Zhang Li Qiang
Published: March 2010

5-axis milling operations are used in industries such as aerospace, automotive and mold for free-form surface machining. In these process, surface quality and material removal rate are of very important. Conservative cutting parameters have been mostly used since there was a lack of physical models and optimization tools. Part and tool deflections under high cutting forces may result in unacceptable part quality. The overall goal of this research is the integration of geometric and mechanistic models for cutting process simulation and feedrate optimization. The extracted cutter workpiece engagements are used as input to a force prediction model. The model predictions for cutting forces and feedrate optimization are compared and verified by experimental results.
Construction of Typical Shell Ring Cutting Database System
Authors: Liu Xian Li , Liu M. , Han Hai Ying , Li W.T. , Zhang Jing Li
Published: March 2010

According to the process characteristics of shell ring, the cutting parameters have been optimized by adopting appropriate boundary conditions at different machining stages and the optimal cutting parameters have been achieved. The objective function and constraints boundary have been stored into the database, which form basic data structures of database. Cutting parameters have been obtained for new type tools using rule-based reasoning approach. According to the characteristics of large number of changing tool for shell ring, tool life prediction is designed, which is very favorable for large shell ring processing. In addition, on-site processing recorded video will be added to the database by multi-media technology, which achieves the diversity of data structure.
Industry Relocation and Manufacturing Clusters Upgrading
Authors: Sun Hua Ping
Published: March 2010

Industrial relocation is conducive to spatial production specialization in the age of information network and economic globalization. Although it will affect the regional industrial competitiveness and employment levels in the short term, in the long run it is conducive to the sustainable development of regional manufacturing clusters. Based on the location model of the micro-enterprise perspective, the paper concluded that: Cournot competition will cause spatial agglomeration, while Bertrand competition leads to industrial relocation. At the present stage, the development mode of manufacturing clusters in Zhejiang is close to Bertrand competition. To achieve the restructuring and upgrading of manufacturing clusters, it is necessary to implement desiring policies to promote the competitiveness of enterprises out of the Bertrand competition, and to increase R&D inputs to enhance the degree of product differentiation. Finally, the paper did an empirical study with an example of Taizhou sewing equipment manufacturing cluster.
A Means of Drawing for Perspective Ellipse and its Applications
Authors: Yu Xi Fa , Yi Su Jun , Zhu Yu , Yang Sheng
Published: March 2010

There is no fixed form for circles not parallel to drawing, with the lens ellipse, and perspective ellipse changes with the size of circle, distance from the screen angle and the relative location of sites location. It is a hardful thing both for manual and for computer graphics. A mathematical model procedure is developed according to the perspective transformation, as long as inputting size of circle, distance from the drawing (coordinates) to the relative angle, as well as site location (coordinates), other parameters to determine the size, and the direction and position of perspective ellipse is determined.
Research of Manufacturing Information Recommendation Model Based on Pattern Mining
Authors: Liu D.S. , Ju Chun Hua , Tian Hao
Published: March 2010

Existing enterprises information systems seldom take different requirement tendency of different personnel into consideration. The idea of Manufacturing Information Active Recommendation was put forward to transfer proper information to proper personnel correctly and timely. The demand sequence behavior access pattern tree was constructed based on the different requirement of user's identity, location and business needs in Web environment manufacturing information. Historical situation similar to current situation could be sorted by its value, and the Behavior could be determined and output based on the association between the highly similar historical situations. Finally, an example was provided to demonstrate the effectiveness of the information modeling process frequent sequence behavior access pattern tree and the model.
A Fuzzy Dempster Shafer Method and its Application in Plant Location Selection
Authors: Deng Yong , Su Xiao Yan , Jiang Wen
Published: March 2010

Selecting a plant location can be seen as a multiple-criteria decision-making (MCDM) problem. In this paper, a new decision model based on our proposed fuzzy Dempster Shafer method for selecting plant location under linguistic environments is presented. The decision result can be obtained through Dempster combination rule. It is shown that the proposed method can efficiently deal with uncertain information processing in MCDM. A numerical example to select plant location is used to illustrate the efficiency of the proposed method.
A Bi-Objective Order Allocation Optimization Model for Horizontal Manufacturing Collaborative Alliance
Authors: Cheng Fang Qi
Published: March 2010

Horizontal manufacturing collaborative alliance is a dispersed enterprise community consisting of several enterprises which produce the same kind of products. To correctly assign order among member companies of horizontal manufacturing collaborative alliance is one of the most important ways to improve the agility and competitiveness of manufacturing enterprises. For the order allocation problem, a bi-objective optimization model is developed to minimize the comprehensive cost and balance the production loads among the selected manufacturing enterprises. Non-dominated sorting genetic algorithm (NSGA-II) is applied to solve the optimization functions. The optimal solution set of Pareto is obtained. The simulation results indicate that the proposed model and algorithm is able to obtain satisfactory solutions.
Study on NC Machining Technology for Integral Impeller of Pelton Turbine
Authors: Wang B. , Liu Xian Li , Yue Cai Xu , Du J.C. , Xu L. , Chen X.Q.
Published: March 2010

Integral production technology of impulse turbine runner effectively prevents phenomenon of bailer broken when generation unit working, and then improving its service life. Based on comprehensive application of vibration inhibition technology and machining optimization path CAD/CAM technology, the high-speed plunge milling process is forwarded in this paper under the condition of big slenderness ratio and be able to present processing vibration. By using matching principle of tool connection point surface smoothing processes and the helix curved surface processing method this process successfully solves the problem of interfering point state complex in finishing plunge milling impulse water turbine whole runner and it achieves high active finish machining by three-axis NC process. This technology has also successfully been used in the power station whole runner manufacturing process in HPE group.
Current Status and Countermeasures on Informatization of Medium and Small-Sized Logistics Enterprises in China
Authors: Wang Jun Qiang , Zhang Cui Lin , Zhang Song Fei , Chen Jian
Published: March 2010

Focused on medium and small sized logistics enterprise (MSLE) in China, the characteristics are analyzed and existing issues are addressed based on the comprehensive investigation results of current levels of informatization of MSLEs covering investment, infrastructure, awareness, strategy, integration, standardization and qualified talent. Taking full consideration of China’s national situation, the development opportunities of MSLE’s informatization are discussed in terms of the powerful national informatization strategy, the key support on logistics industry, the pressing demand on logistic service generated by manufacturing industry, the intense competition among logistics software suppliers, the rapid development of public logistics information platform and advanced logistics technology development. Furthermore, the corresponding countermeasures at the aspects of enhancing soft power, utilizing external consulting services, popularizing compact and efficient information platform, keeping fast and smooth informatization construction policy, and strengthening project management and associated regulations are presented to help promote the informatization progress of MSLE in China.
Customer Requirements Capture for Product Development: Framework and Method
Authors: Gao Fei , Xiao Gang , Zhang Yuan Ming
Published: March 2010

Although QFD is powerful for translating customer requirements to control parameters of product design and production process, how to capture and understand requirements rapidly, accurately and economically so that the products can deliver themselves of customers is still a bottle-neck. This paper proposes a theory framework for capturing customer requirements. First, the problem for customer requirements capture is formalized. Second, three phases including requirements gathering, requirements mapping and requirements evaluating are advanced, and a method named iterative arithmetic to determine the weights of requirements is also developed. Finally, the proposed methodology is effectively demonstrated in an instance of requirements capture for reading lamp of computer.
A Computer-Aided Ergonomics Evaluation System for Customized Furniture Design
Authors: Wu Qun , Sun Shou Qian , Dong Zhan Xun
Published: March 2010

Customized product development is facing the challenges of maintaining mass producibility and exploring customer perception on target products. The objective of this study was the application of ergonomic evaluation method for customized furniture design in virtual environment. At the first, the system architecture was built, and gordian techniques of the system were analyzed. Then a representative case was studied. In this case study, 3D scanning system and Motion Capture were used to get information of given user/users, REBA and Lifting Index (LI) of revised NIOSH lifting equation were selected as ergonomics evaluation methods. The prototype’s usability was verified by the result. This method can also be used to solve other relative problems.
Applied Study on the Mine Production & Management Decision Support System Based on Data Warehouse
Authors: Li Xue Feng , Zhong Shu Yu
Published: March 2010

With accumulating data in mine production, integration of the existing separate information systems is of great importance in enhancement of both production management and support decision-making. BIStar, a production & management decision support system base on data warehouse technology was developed as a user-friendly data analysis, display and decision support tool, and was presented with illumination of its main framework and detailed discussion of its certain key points of the subsystem, such as data acquisition system, central database system, access tools. An application example of information analysis conducted by a large mine corporation was also cited for analysis of feasibility & cost-effectiveness.
Problems and Countermeasures of the Quality-Tracing Based on Lot Numbers in Manufacture
Authors: Lei Qi , Pan Li Wei , Yi Shuang Qing , Song Yu Chuan
Published: March 2010

In order to solve the problems of quality-tracing based on Lot Numbers, the corresponding methods were proposed, including the secondary marking method to solve the traceability information loss caused by the attrition of Lot Number, the coordinated coding mechanism among upstream and downstream enterprises and data sharing mode to solve the "Lot Number Isolated Island" in the quality traceability chain, and the “van following parts” mode of inner logistics to solve the management confusion of the work-in-process parts caused by merging, splitting and mixing the batch of the parts. In addition, the feasibility, cost and constraint conditions of the methods proposed were discussed. Finally, the practicality of the research program was illustrated by the application of specific cases.
Knowledge-Based Web Service Environment for 3D Visualization
Authors: Yu Jiang Ning , Cai Hong Ming , Jiang Li Hong
Published: March 2010

Aiming at implementing knowledge reusability and high efficiency in the design process, this paper brings up a knowledge-based web service environment for 3D visualization (KWSE). KWSE proposes clearly: encapsulating geometry APIs to web services, knowledge fusion process and knowledge database management. To implement the construction it forms knowledge service model and knowledge-driven web service architecture. Following this architecture, a knowledge-driven 3D visualization system has been built using Open CASCADE geometry engine and WISF technology.
Numerical Simulation and Process Test for Cold Extrusion of Wheel Hub Bearing Rings
Authors: Meng Bin , Wu Hai Wei , Bao Guan Jun , Li Hui , Yang Qing Hua
Published: March 2010

This paper describes procedures and results obtained using 3D rigid plastic thermal-mechanical finite element model of wheel hub bearing rings. Numerical simulation for cold extrusion process is performed and metal flow characteristics, distribution of effective stress & temperature field and load-stroke curve are analyzed. Approach of tool wear prediction is also explored using Archard model . Process test revealed that numerical simulation provides theory basis and useful guidance for cold extrusion process specification and die design.
Structural Transformation in Electric Pulse Modified Liquid Aluminum
Authors: Qi Jin Gang , Wang Jian Zhong , Zhao Zuo Fu , He Li Jia , Wang Bing
Published: March 2010

The modification of liquid metal by electric pulse (EP) is a novel method for grain refinement. In this study, based on the reported structural heredity of EP-modified liquid aluminum, the structure tests of EP-modified liquid aluminum were conducted by using high temperature X-ray diffractometer. The results show that the EP-modified liquid structure also tends to be slack and unordered with increasing temperature, which is similar to that of the unmodified. However, the quantitative characterization denoted by the liquid structure parameters exhibits their discrepancy. At the modifying temperature of 750°C, the order degree of EP-modified liquid aluminum is remarkably strengthened and the value of average atomic number per cluster changes from 119 (no EP) up to 174 (EP) by an increase of 46%. These tests experimentally testified Wang’s electric pulse modification (EPM) model that was built only by phenomenology and hereby the mechanism of grain refinement resulting from EPM is further elucidated.
Effects of Low Frequency Electromagnetic Field on Hot Tear during Hot-Top Casting Process
Authors: Wang Xiang Jie , Cui Jian Zhong , Zhu Qing Feng , Zhao Zhi Hao
Published: March 2010

Hot tear is one of the main defects during the aluminium casting process, and it usually occurs during solidification. In this work, the low frequency electromagnetic field was applied to study the effects of low frequency electromagnetic field on hot tear during the conventional hot-top casting process. The results show that under the effect of the low frequency electromagnetic field, the structure of the ingot is refined, the flow direction is changed, and the depth of the sump becomes shallow. All these factors can decrease the hot tear susceptibility.
Effects of Magnetic Field on the As-Cast Structures of Dual-Ingot Low Frequency Electromagnetic Semi-Continuous Casting
Authors: Wang Gao Song , Zhao Zhi Hao , Cui Jian Zhong , Dong Shuai
Published: March 2010

Based on the non-uniform distribution of magnetic field within the ingot caused by its interactions during the dual-ingot low-frequency electromagnetic semi-continuous casting process, a three-dimensional finite element model was constructed. This model was meshed and calculated with the ANSYS software, and the distribution of magnetic field in low-frequency semi-continuous casting mould was obtained. The influence of the distance and current directions between two coils on magnetic field distribution in the ingot was studied. Calculated results showed that, during dual-ingot low-frequency electromagnetic semi-continuous casting process, whether the current was in the same direction or the reverse, magnetic field density on the remote end should be greater than that on the proximal of the same ingot; when the current directions of nearby coils were reverse, the magnetic intensity on ingot was higher than that with the same directions; as the distance between coils increased, the distal and proximal difference of magnetic flux density declined. Based on the results, a casting mould for dual-ingot electromagnetic semi-continuous casting ø152mm 7075 aluminum alloy was designed and produced. The experimental results showed that when the current directions of nearby coils were reverse, the as-cast macrostructures were a little bit better than that with the same directions. Moreover, when the current directions were reverse, the heterogeneity of the as-cast inner structure could be almost ignored.
An Investigation on the Overheating of A357 Aluminum Alloy
Authors: Pan Jie Hua , Zou Yong Zhi , Lin Yi , Zeng Jian Min
Published: March 2010

The structure and properties of A357 aluminum alloy with different second dendrite arm spacing (SDAS) in different situations of overheating were investigated. The results indicate that serious overheating characteristic structure takes on compound melting ball, crystal separating phase and overheating triangle section; The overheating level of A357 alloy raises with solution temperature increasing; The mechanical properties decrease with the overheating level increasing; The overheating temperature of casting increases as the SDAS decreases, the regression equations of the correlation between SDAS and overheating temperature is as follows: T = 575.46-0.213SDAS; Optimum solution temperature could be selected for A357 alloy with different SDAS depending on supercritical solution region proposed in this paper.
Effect of Aluminum Content on Mechanical Properties of Cast Magnesium Alloy Sheets Fabricated by Twin-Roll Casting
Authors: Watari Hisaki , Nishio Yoshimasa , Nakamura Ryoji , Davey Keith , Koga Nobuhio
Published: March 2010

This paper describes the twin-roll casting technology of magnesium alloys that contain relatively high weight ratios of aluminum, such as AM60, AZ91 and AZ121. The magnesium alloy sheets were cast by a vertical roll caster to manufacture relatively high-strength Mg alloys with high aluminum content. The influences of such process parameters as roll materials, casting temperature, and roll speed were ascertained. A simple method of predicting the convection heat transfer coefficient between casting rolls and molten metal is introduced. The microstructures of cast magnesium alloy sheets are microscopically observed to investigate the effects of roll-casting conditions on crystal growth in the cast products. It was found that Mg alloys with high aluminum content can be fabricated at a roll speed of 90m/min with a vertical-roll caster. The grain size of the manufactured wrought magnesium alloy sheet was about 30 micrometers due to rapid solidification in the proposed process.
Damping Characteristics of Biomedical Porous NiTi Shape Memory Alloy
Authors: Jiang Hai Chang , Liu Shu Wei , Li Xiu Yan , Rong Li Jian
Published: March 2010

One internal friction peak associated with the B2↔B19’ transformation appears on the cooling curve of porous NiTi shape memory alloy and the dense NiTi alloy shows the maximum peak. The tan δ value increased with the increasing of strain amplitude and the decreasing of frequency. Tan δ value of porous alloy mainly comes from the energy absorbing of the matrix at the small strain amplitude, however, if the strain amplitude is large, the tan δ value comes from the energy consumption that overcomes the friction between folds and the plastic contribution.
Preparation of Superfine Low-Melting-Point Metal Particles by Phase Inversion Method
Authors: Chen Zhang , Ma Han Bing
Published: March 2010

Bi-Pb-Sn-Cd metal particles were fabricated with dispersant sodium oleate by phase inversion method. The effects of dispersant content, temperature, and stirring speed and the average size of Bi-Pb-Sn-Cd metal particles were investigated by scanning electron microscope and particle size distribution analyzer. In addition, the preparation mechanism was preliminarily discussed. Finally, the optimized preparation conditions were determined and well-dispersed superfine Bi-Pb-Sn-Cd particles with average diameter of about 0.3μm were obtained.
Preparation and Characterization of Ce-Doped Ba0.2Sr0.8TiO3 Ferroelectric Ceramics
Authors: Han Dong Fang , Tang Qun , Zhang Qing Meng , Wang Lei , Du Ju
Published: March 2010

The structure and property of Ce-doped Ba0.2Sr0.8TiO3 (BST) were investigated as a function of Ce content. The density experiment results confirmed that increasing the Ce doping ratio caused the decrease in shrinkage factor of BST in the sintering procedure. Additionally, both Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) analysis showed that the grain size of Ce-doped BST was dependent on the Ce content. Further more, the dielectric constant and dielectric loss had a curve relationship with increasing Ce content. The improvement of the electrical properties of Ce doping BST may be related to the decrease in the concentration of oxygen vacancies. According to the research, the diameter of grain, the dielectric constant and loss factor of the 1mol% Ce-doped Ba0.2Sr0.8TiO3 were 500nm, 365.8 and 0.0063, respectively.
Tribological Behavior of Ti(C, N)-Based and Functionally Gradient Ti(C, N)-Based Cermets
Authors: Shi Zeng Min , Feng Ping , Liu Wen Jun , Zheng Yong , Li Jian
Published: March 2010

Ti(C, N)-based cermet and functionally gradient Ti(C, N)-based cermet were prepared by vacuum sintering and post surface heat-treatment in nitrogen, respectively. Tribological behaviors of obtained cermets were comparatively studied. Dry sliding wear and cutting test were conducted against quenched medium carbon steel. It was found that a graded structure formed and the surface hardness of functionally gradient Ti(C, N)-based cermet was improved. Friction coefficients of both cermets decreased with the increase of the sliding speed. The friction coefficient of Ti(C, N)-based cermet was lower than that of functionally gradient Ti(C, N)-based cermet at the conditions of higher sliding speed and higher load. The cutting test demonstrated that Ti(C, N)-based cermet exhibited better cutting performance and higher wear resistance than the cemented carbide YT15, cermet TN20 and functionally gradient Ti(C, N)-based cermet, while the functionally gradient Ti(C, N)-based cermet exhibited a similar performance as YT15 and TN20.
The Exploration on Synthesis of Calcium Aluminate and Fe-Si Alloys Using Red Mud and Aluminum Dross
Authors: Hu Jian Bao , Li Yuan Bing , Wu Kai Dao , Liu Fang , Zhu Quan , Li Ya Wei
Published: March 2010

Calcium aluminate and Fe-Si alloys were successfully synthesized by using red mud and aluminate dross as the main raw materials in the lab-scale experiment. Three apt experimental parameters were obtained: 1.2 times of theoretical addition amount of aluminum dross, binary basicity of raw materials 0.9, 40min smelting time. The chemical compositions of calcium aluminate synthesized meet the standard of CA-60 cement of China, and the calcium aluminate can be used as pre-melted-slag in Steelmaking process.
Study on Friction Properties of Cu-Based Friction Materials with Ni Coated Nano-SiO2 Particles
Authors: Du Jian Hua , Han Jian Guo , Tu Jiang Ping , Xu Cheng Fa
Published: March 2010

The Cu-based friction material with Ni coated nanometer SiO2 (Ni/n-SiO2) particles was prepared by the powder metallurgy technology. Friction properties of the friction materials were evaluated by a friction tester. The microstructure and worn morphology were characterized by optical microscope (OM) and scanning electric microscope (SEM). The results indicate that the microstructure is uniform. The Ni/n-SiO2 particles can enhance the wear ability of Cu-based friction materials. The wear rate of the friction material with Ni/n-SiO2 is 6.58 times of that without Ni/n-SiO2. The main wear mechanisms are abrasive wear and adhesive wear, and Ni/n-SiO2 particles can reduce the abrasive wear and adhesive wear.
Synthesis of High Nitrogen Stainless Steel Powders by High Energy Ball Milling and their SPS Compaction
Authors: Cui Da Wei , Wang Jin Long
Published: March 2010

High nitrogen nanostructured Fe-17Cr-11Mn-3Mo stainless steel powders were produced by high energy ball milling under a nitrogen atmosphere. It was found with increasing the milling time, the nitrogen contents of the powder mixtures increase linearly up to 1.98 wt pct after 96h, and a linear regression equation, WN = 0.19357 + 0.01887t , has been further established. In addition, with the increased milling time, the crystallite sizes and particle sizes of the powders decrease continuously, the lattice strains and sphericity of the powders increase gradually. After milling 60h, the high nitrogen nanocrystalline stainless steel powders with a fine particle size range of 5~10μm, excellent sphericity and uniform components can be obtained, whose crystallite size is about 5.0nm and lattice strain is about 1.0%. The powders milled for 60h was compacted using spark plasma sintering process at different temperatures. It is found that a fully austenitic high nitrogen stainless steel with almost full densification can be obtained by SPS at 1000°C, whose nitrogen content is 0.82 wt pct.
On Spontaneous Austenite Recrystallization of Low Pressure Rotor Steel 26Cr2Ni4MoV
Authors: Ni Li Yong , Kang Peng Chao , Huo Zhi Yi , Liu Zhu Bai
Published: March 2010

It is difficult for the dynamic recrystallization to happen in Steel 26Cr2Ni4MoV, used to manufacture low-pressure steam turbine rotors generally. Static recrystallization was important in the fine crystals generation. Considering this, thermo-torsion method was adopted to investigate the spontaneous austenite recrystallization of steel 26Cr2Ni4MoV. Results show that even minute strain can promote the nucleation and growth of spontaneous austenite recrystallization dramatically, and the increase of temperature can also do so. The discovery can contribute to the realization of controlled forging.
Research on Manufacturing Technology and Heat Transfer Characteristics of Sintered Porous Surface Tubes
Authors: Wang Xue Sheng , Wang Zheng Bian , Chen Qin Zhu
Published: March 2010

A new process for manufacturing sintered porous surface tube has been developed. By using this technology, three kinds of sintered porous surface tubes were fabricated, which base material was carbon steel and the sintered layer was bronze powder. And their boiling heat transfer characteristics were investigated experimentally. The experimental results indicated that the boiling heat transfers coefficient and the heat flux of these porous surfaces tubes were increased by 8~14 times and 5~8 times respectively compared with the smooth one. Finally, a new high flux heat exchanger was designed and applied instead of conventional one in a refinery.
Process Investigation for Purifying Hydrated Silica from Fly Ash by Acid and Alkali Combination Method
Authors: Li Feng , Liu Xiang Dong , Guo Yuan He
Published: March 2010

In this paper, with sodium carbonate as an auxiliary agent in the fly ash, the mixtures were sintered at 880°C for 90 min, then dissolved by different concentrations of sulfuric acid respectively for extracting the hydrated silica. The results show that when the activated ash fly is dissolved by different concentrations of sulfuric acid, the dissolution rates of ash fly increase with the concentration of sulfuric acid increasing. Impurities of aluminum and iron atoms are present in an orderly array of micro-andalusite structure in the generative hydrated silica. When they are dissolved by sulfuric acid for 2%(wt%), the orderly structure is destroyed obviously, and the aluminum and iron atoms are separated out. The purity of hydrated silica can reach 99.9%.
Post-CMP Cleaning of Atom-Scale Planarization Surface of Computer Hard Disk Substrate
Authors: Bu Nai Jing , Lei Hong , Chen Ru Ling , Hu Xiao Li
Published: March 2010

At present, the surface of computer hard disk substrate has reached atom-scale planarization after chemical mechanical polishing (CMP). Post-CMP cleaning is one of the key factors influencing the CMP performances. During cleaning, cleaning solution and cleaning methods play a key role in cleaning quality and effectiveness. In the present paper, alkylpolyoxyethylene alcohol carboxylic ester (FAC) surfactant was synthesized and its cleaning performances on atom-scale planarization surface of computer hard disk substrate were investigated. Microscope analysis indicated that the prepared detergent containing FAC surfactant exhibited improved cleaning performances compared with the commercial detergent. Further, inductively coupled plasma (ICP) atomic emission spectrometer, auger electron spectrogram (AES) and atomic force microscopy (AFM) analyses after static corrosion test showed that the prepared cleaning solution had lower corrosion to hard disk substrate.